# Compact camera that can get the shortest depth of field?



## pubius (Dec 21, 2006)

I know that in general, p&s cameras have too short a focal length, and too limited ap. settings to get a small depth of field. Wondering if anyone knows one that gets closer to being able to achieve smaller d.o.f without shooting macro way up close. Thanks for anyone's help.


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## myopia (Dec 21, 2006)

sony makes a 2.8 cybershot w/ 8.1 mp. that's all i got to help.


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## Don Simon (Dec 21, 2006)

I'm assuming you mean digital. If not there are several fixed-lens compact film cameras that would fit the bill. Otherwise I think the majority of fixed-lens compact digital models have f/2.8 or slower lenses. The Canon Powershot G6 has an f/2.0-f/3.0, and one of the Panasonic FZ models had a constant f/2.8, so that might be the best you can get in compact models. I'll give the usual advice here and say an SLR with a fast prime lens is the best way to achieve shallow DOF, but obviously a dSLR may not be the right choice for you, in which case the Powershot and Panasonic are both highly regarded.


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## markc (Dec 21, 2006)

Unfortunately that's the biggest I've seen also.


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## darich (Dec 22, 2006)

I'm pretty sure my Canon A85 can open up to f/2.8 but it seems when ever i use it the depth of field isn't anywhere near as shallow as it is when using my SLR


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## Big Mike (Dec 22, 2006)

Even though some digi-cams can open up to F2.8....part of what determines DOF...is the size of the recording medium...and with all the compact digi-cams...the sensor is very small.


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## markc (Dec 22, 2006)

As I understand it, it's not the size of the sensor directly, but the short focal lengths they have to use. The f numbers are a ratio, not a direct measurement of size. f2.8 on a 50mm is an opening about 19mm in diameter. On a 9mm lens (one camera I looked at has a range of 5.8mm-17.4mm for its lens!), f2.8 is only 3mm. 3mm on a 50mm lens is f16! Cropping comes into play, which might enlarge the effective area in focus; but still, f16 is a huge difference from f2.8, even if you crop in quite a bit.

As an aside, f2.8 on a 300mm lens is a whopping 107mm across, which is why large aperture telephotos are so expensive. That's like having an f.45 on a 50mm lens. It would be more than twice as wide as it is long!


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## Flash Harry (Dec 22, 2006)

I dont use P&S cams myself but its unessesary to have a wide aperture to put the background out of focus, simply move closer to the subject and focus on what you need sharp, the BG will be out of focus.


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## mysteryscribe (Dec 22, 2006)

frankly in these days of digital editing short depth of field is over rated.


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## markc (Dec 22, 2006)

mysteryscribe said:
			
		

> frankly in these days of digital editing short depth of field is over rated.


Why is that? I find that adding it in Photoshop looks fake to me. Software is great for a lot of things, but smooth dof transitions is not one of them. That's why I don't care for using PS to try and emulate the LensBaby.


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## markc (Dec 22, 2006)

Flash Harry said:
			
		

> I dont use P&S cams myself but its unessesary to have a wide aperture to put the background out of focus, simply move closer to the subject and focus on what you need sharp, the BG will be out of focus.


That doesn't work so great with narrow apertures. Plus you choose a focal length based on how it looks, you may be limited on how close you can get.


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## Big Mike (Dec 22, 2006)

markc said:
			
		

> As I understand it, it's not the size of the sensor directly, but the short focal lengths they have to use. The f numbers are a ratio, not a direct measurement of size. f2.8 on a 50mm is an opening about 19mm in diameter. On a 9mm lens (one camera I looked at has a range of 5.8mm-17.4mm for its lens!), f2.8 is only 3mm. 3mm on a 50mm lens is f16! Cropping comes into play, which might enlarge the effective area in focus; but still, f16 is a huge difference from f2.8, even if you crop in quite a bit.
> 
> As an aside, f2.8 on a 300mm lens is a whopping 107mm across, which is why large aperture telephotos are so expensive. That's like having an f.45 on a 50mm lens. It would be more than twice as wide as it is long!


I was under the impression that the size of the projected image was a factor.  Don't you get a shallower DOF with medium or large format, at the same aperture (ratio) than with 35mm?  I could easily be wrong though.


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## markc (Dec 22, 2006)

That depends on how you do the comparison. A smaller film/sensor is just the same as a crop if you are using the same lens. But if you are comparing  "normal" lenses, then you are comparing a 50mm to an 80-90mm. At f2.8, that's an aperture of 19mm on the 35mm film camera and an aperture of 30mm on the MF camera. Thats a much wider aperture for a normal MF lens, so you will get less DOF. I personally think that the actual aperture size might be more useful info than the ratio. I wonder why they went with that for a label. Maybe I'm missing something about how the focal length itself affects DOF, but from the info I find, it doesn't. It's more how we use the lenses. The main reason that telephoto lenses seem to have less DOF is that we use them at greater focal distances, and that the actual aperture opening is larger for the same f number. When you change sensor sizes, the distance to the subject remains the same for its "normal" lens, but the aperture size changes for the same f-stop.


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## mysteryscribe (Dec 22, 2006)

Im sorry I dont agree with the depth of field edit thing. 

I dont use photoshop but a few of the clones. I soften out the objects one at a time not all the same so I don't have a problem although frankly i dont do it often. Most of the things I do are like i would have done them in a dark room. Each object in the frame is treated seperately so I vary the amounts of softness just as you would get with depth of field in the camera and once you pass the very edge of the focus area it is all the same anyway. 

Before you lose it an object ten feet past the focus area is the same softness as one 20 feet. You just need to vary the ones at the edge of the area of focus.

In my opinion you guys are making a mountain out of a mole hill but that is just an opinion. You didn't expect me to agree did you?

Unless someone has changed the way depth of field is managed from medium format to 35mm all lens react more or less the same because of their distance from the film or sensor i would guess. aka focal length of the glass to film. Zooms sometimes dont work the same thought since some of them don't move all the glass just the front elements leaving the rear at the same focal length. At least that what I was alway told.

That being the case I would think the lack of depth of feild has more to do with the fact that the true focal length is a lot shorter on digicams because of the sensor size in pns and full size. I would think you would have more control over it in 35mm film. In other words you would use a larger fstop for the same depth of field with 35mm. The true focal length not the sensor would be the problem. Just a logical assumption.  Which in photography is probably going to make the north end of a south bound horse of me


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## Flash Harry (Dec 22, 2006)

markc said:
			
		

> That doesn't work so great with narrow apertures. Plus you choose a focal length based on how it looks, you may be limited on how close you can get.


 
Going off what the first poster said getting up close is no problem, narrow apertures are not a problem either depending on how distorted you want the background, in studio I shoot f11, my subjects are pin sharp, the background 5 feet away is not, I rarely shoot from a distance of more than 10 feet with a 135mm lens, with digital slr, outdoor wedding f8-11 at 70mm from roughly 8 feet the background is also blurred, I choose my focal length to suit the task and take the appropriate position to achieve the "look"


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## markc (Dec 22, 2006)

I should have been more specific, but didn't mean to say that you couldn't blur the background at all. They mentioned a small DOF specifically. There's a huge difference to my eye between f1.8 and f11 with my gear. You won't get this with f11.

I also doubt that someone could get a convincing smooth gradient to the bokeh when something is angles off into the distance without a lot of work. This shot would be an easier one, but not so when you have intricate structures involved. Even this one would require a lot of tracing out of the grass blades.


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## mysteryscribe (Dec 22, 2006)

Tell you what I got a lot of time you post a sharp one and I'll make it a short depth of field for you.  Lets see how many people can tell the diference.


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## Don Simon (Dec 23, 2006)

Leaving compact p&s cameras aside for a moment, I'm not convinced the bokeh I get with my 50mm f/1.4 or 85mm f/2 could be convincingly simulated in software, at least not without a _lot_ of effort. Btw I'm not trying to show off or say you need expensive gear; each of those lenses cost about $50. But if I wanted shallow DOF and pleasing bokeh I would do it with a prime lens (with film if not digital body) rather than a compact zoom p&s with or without software.


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## darich (Dec 23, 2006)

ZaphodB said:
			
		

> Leaving compact p&s cameras aside for a moment, I'm not convinced the bokeh I get with my 50mm f/1.4 or 85mm f/2 could be convincingly simulated in software, at least not without a _lot_ of effort.



Like Mark , i find that any false blurring edited into an image to make it look like a shallow depth of field is obvious. It may depend on who did the work (obviously) and i don't doubt the actual image would have an effect on how it comes out.

It could be that your eye is more perceptive than you think and fake shallow DOF looks fake because the eye can tell that from the main subject. Could be wrong there though.

I still think it looks fake....at least it has in the shots i've seen.


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## Ducks_own (Dec 23, 2006)

yeah, I still haven't gon aboutlearning all the stuff like DOF... But my camera's  f=7.9 to 23.7mm... For the record, it's a casio EX-Z120.


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## RMThompson (Dec 23, 2006)

Personally I use a Canon A610 point and shoot, and it is decent with DOF.

Check out some of my pics here:

http://www.flickr.com/photos/rmthompson/

Some of them with a decent DOF:


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## markc (Dec 23, 2006)

RMThompson said:
			
		

> Personally I use a Canon A610 point and shoot, and it is decent with DOF.


That's better than I expected, though it looks like you are rather close to the subjects in all of those cases. I wonder how it would do when the subject is 12' away or more, which is the kind of situation I was talking about. I like the use of the wide angle in the trumpet one, but for the second one, I'd prefer a longer lens, which would put you further back.


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## markc (Dec 23, 2006)

mysteryscribe said:
			
		

> Tell you what I got a lot of time you post a sharp one and I'll make it a short depth of field for you.  Lets see how many people can tell the diference.


Sounds good, though I don't have one handy. Most everything I shoot already has a short DOF.


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## mysteryscribe (Dec 23, 2006)

I'll be around and the offer is always good.


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## mysteryscribe (Dec 23, 2006)

Like it or not I bet I can pass this off in the gallery as a short dept of field shot and very few if any will notice that it isnt.


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## RMThompson (Dec 23, 2006)

markc said:
			
		

> That's better than I expected, though it looks like you are rather close to the subjects in all of those cases. I wonder how it would do when the subject is 12' away or more, which is the kind of situation I was talking about. I like the use of the wide angle in the trumpet one, but for the second one, I'd prefer a longer lens, which would put you further back.


 
Check out my FLICKR.

A lot of those are cropped very tight too, giving teh illusion I was close. I was almost 2 feet away from the fish.

http://www.flickr.com/photos/rmthompson/


http://www.flickr.com/photos/rmthompson/


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## markc (Dec 23, 2006)

Not to be picky, but 2' is _very_ close. The minimum focus on my 50mm is 1.5', and my 85mm won't even focus under 3'.


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## darich (Dec 24, 2006)

mysteryscribe said:
			
		

> Like it or not I bet I can pass this off in the gallery as a short dept of field shot and very few if any will notice that it isnt.



A lot of people would be fooled but on one of the melons (?) the bottom edge is blurred and is inconsistent with shallow DOF.
Additionally, the ledge they're sitting on is consistently blurred - in other words the surface nearer the camera looks as blurred as the surface at the melons but in real life it would be more blurred nearer the camera.

You're right to say that most people wouldn't spot the difference though and to be honest it's pretty good - it's not obviously fake but on close examination it can be seen. If that image wasn't posted in this thread then i wouldn't give it another glance as being false.


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## mysteryscribe (Dec 24, 2006)

thanks and the truth is>>> if you were trying to make a true art fake you would have done even more.... So it is not only possible to fake depth of field the same is true with anything.

Point being we buy equipment for lots of reasons and fool ourselves about the real reason.  I have to have a *whatever* to do this when in reality you dont at all.  I have this conversation with my son in law all the time.


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## RMThompson (Dec 24, 2006)

mysteryscribe said:
			
		

> thanks and the truth is>>> if you were trying to make a true art fake you would have done even more.... So it is not only possible to fake depth of field the same is true with anything.
> 
> Point being we buy equipment for lots of reasons and fool ourselves about the real reason. I have to have a *whatever* to do this when in reality you dont at all. I have this conversation with my son in law all the time.


 
You are 100% correct here. I always hear people telling me that I won't achieve a certain effect until I purchase *magical item*.

However it's not true. 

Look at this picture of mine:






If you didn't know me, and I asked someone to guess the equipment used they would guess a DSLR, a strobe setup, and a white muslin background, for a total of, say, 1500 dollars worth of equipment.

Truth is, I used my PnS Canon A610 (as always) and the same WalMart lamp Ive been using for the past two months. I did purchase a halogen additional light, but didn't use it for this shot.

The background is a fuzzy blanket that I slept on last night. It's really comfortable.

Of course some post processing work went into this, but nothing that Picasa 2 couldnt handle, minus adding the border.


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## mysteryscribe (Dec 24, 2006)

the truth is the subject helps to hide a multitude of sins. Your subject and handling is faultless so who really is going to examine the background for flaws. If something like this is lite flat, trust me no one is going to notice.

You help me not only make my point but to make several others. Those bridge cameras like the panasonic high end models may well do all that is needed by any photographer and the rest is just ego. But I can't say since I don't shoot digital.

I do know the difference between a hundred dollar lens in film and a thousand dollar lens is just more of the same.  Given the choice the average customer would not pay more for the results. The truly knowledgable customer might, but the average customer that photographers have daily wouldn't, even if he could see it.


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## markc (Dec 24, 2006)

Sorry. It looks like petroleum jelly on the lens to me, not bokeh. Maybe someone who is a beginner or "average" isn't going to spot it right off, but I'm not happy with my own work being just average. My goal is to continuously improve both my knowledge and skill.

For me, it's about picking the right tool for the job. You might be able to dig a hole with a garden rake, but I'd rather use a spade. There are certain things you can do in software in an excellent manner, like color balance, contrast adjustment, etc. Even montages in the manner of Jerry Uelsmann, if you have the right source material. Things like bokeh, infrared, and trying to change the quality of light (direct to diffuse, etc.) are a lot more work and less convincing for me.

The original poster asked a specific question regarding DOF on small-sensor cameras. I think that alone puts them beyond an "average" photographer, if not in skill then in interest. There's a reason I'll use numbers in examples: there's a science to photography as well as an art. People may think it somehow kills the magic, but ignoring it isn't going to make it any less true. You can close your eyes and make all the wishes you want, but if you jump out of a tree, you are still going to accelerate at a rate of 9.8 m/s/s (adjusted for altitude and wind resistance, which can also be determined). Things like aperture size and focal length matter in a very real and scientific way. There's not magic there. The magic, and art, comes from how we use these effects.

I can understand how people might have a knee-jerk reaction to promoting expensive equipment, but that's not even what I'm doing here. I bought a Mamiya 35mm camera and 55mm/f1.8 lens for $35 off of eBay. It's not so cheap of you want to go digital, especially with the large sensor cameras being so expensive still, but that's the science and the reality of the situation.

Sure, you can fudge it with Photoshop, but you can fudge just about anything in there. It's seems that the "you can use any camera" rant is bumping up against the "Photoshop won't fix a bad picture" rant. Again, I'm not saying that people shouldn't be happy with a software blur. If that's what works for you, great! I just want people to be aware of the differences. Whether the differences matter to you is a personal matter, but at least then you can choose rather than being blind to them. I personally don't find the difference in the "L" lenses compare to what I have now to be worth $1000+ for me right now, but at least I know that there is a difference if I ever need tack-sharp images; I'm not left thinking that they are just a marketing ploy. The physics of quality glass is very real. I'm not ignoring it, I'm saying that it's not important to my photography right now.

I also say that the "bridge" cameras are great for most things, but very shallow DOF of subjects at a distance, as with a long focal length, isn't going to be one of them. That has nothing to do with ego; that's the science. Whether that matters, or if a software blur will be good enough, is up to you. You decide. I'm not trying to do that for you.


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## markc (Dec 24, 2006)

mysteryscribe said:
			
		

> If something like this is lite flat, trust me no one is going to notice.


Wow, you make an awful lot of broad statements as if they were the truth. *I'll* notice. I'll see the wrinkles in the sheet and the glare on her cheek, too. I'm not so hypnotized by the breasts that they'll dull my photographic eye to the point that these things don't jump out at me. Nice of you to speak for everyone.

I'm not saying that he needs more expensive equipment to do what he wants or that this is a bad shot. Far from it. But I can certainly tell the difference between this shot and one from a fashion magazine.


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## mysteryscribe (Dec 24, 2006)

Mark most of what you say has little to do with me so I dont have an opinion. But I take exception with one factual and one perceptive issue.

Factual...patroleum jelly would have a uniform softness not a graduated one. 

Perceptual: Everyone makes universal statements. I can say everyone is opposed to the concept of war and sure as hell someone will say but i love carnage and death. When you say everyone, I think it is understood it is not truly going to be everyone. That there will indeed be some minority of people who see things differently. I personally don't pick every picture I see apart. I'm just not that interested past, is it a good picture, and that one is.

As for the other issues you raise, I leave that to anyone else who is interested. I certainly have no use for photoshop but I don't deny what it can do either.

Let me just add one thing I forgot.  Depth of field as we are using it here is softness around the end of the zone of focus and It begins imperceptably before and after the subject and increases as it get farther away.  There is absolutely nothing mysterious it.  

Certainly there is nothing that makes that gradual sharpening and softening different in the purely created lens version and not in the editied version.  Not so long as the softness gradually decreases as it moves to the subject and increases again after it leaves the subject.  There is absolutly no way a soft image can look different because it was created by a lens.  A poorly done, as mine obviously was, edit created variation of softness looks like just that a poorly done one.  But to say there is a difference in softness that can not be created any other way is foolishness in my opinion.


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## Mad_Gnome (Dec 24, 2006)

The question of whether or not Photoshop-created DOF works for you will be solved mainly by one question: how much is your time worth? If you're only doing one or two photographs, the extensive amount of work to recreate what a good lens can do inherently might be worth the initial money savings. If you're intending to put that much work into an extensive number of photographs...how much time will that take you? What kind of hourly rate is your time worth? Multiply those two and see if it costs the same as a 50mm f/1.8 lens, which is fully capable of creating a very narrow DOF. Or a 50mm f/1.4, for that matter. Or any of a few dozen other lenses that can recreate the same effect. Add in the cost of Photoshop itself, which retails for more than twice what my 50mm f/1.4 did. Are you still saving money?

Can Photoshop recreate the effect with a reasonable degree of success? Yes. But is it worth it when it can be created more quickly, more easily, and for less investment with the proper equipment?


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## mysteryscribe (Dec 24, 2006)

I have absolutely no arguement with that reasoning. 

Just don't try to kid me that to get that effect you have to buy a thousand dollar lens and nothing else will do. First of all I agree that any 1.4 1.8 or even 2.8 will do that. So you have to crop a little instead shooting from the next county. Sorry I just don't buy into the the fill a room full of stuff to produce one picture a week. A proof can be softened in a few minutes and a finished image for printing in twenty minutes max. To tell someone they can't do it any other way but to buy the expensive lens just isn't true.


By the what exactly does the rate of acceleration have to do with depth of field and being about to create it stating with a bridge camera.


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## markc (Dec 24, 2006)

mysteryscribe said:
			
		

> Factual...patroleum jelly would have a uniform softness not a graduated one.


So thickness or smoothness of application will have no effect? Interesting.
Well, I was just picking the closest thing it looked like to me anyway. It didn't look like bokeh to my eyes. Notice that I never stated that view as a fact, because it's not, nor did I claim to speak for everyone. Some people may think it looks like bokeh, and some may think it looks like something else entirely.



			
				mysteryscribe said:
			
		

> When you say everyone, I think it is understood it is not truly going to be everyone.


I don't, and I consider that lazy communication. I guess it's getting outside the realm of photography, but the reason I brought it up is that I think it does those who are trying to learn a disservice. How are they supposed to distinguish between everyone and "everyone"? Your use with the image above is a perfect example. Maybe everyone you know wouldn't notice the difference, but in my circle, the vast majority _would_*. They are all accomplished photographers after all (much more so than I), and this is a photography web site. Should I then say that everyone _will_ notice a difference? I personally don't think I should.



> There is absolutly no way a soft image can look different because it was created by a lens.


How about your image above? It certainly looks different from lens blur to me.



> A poorly done, as mine obviously was, edit created variation of softness looks like just that a poorly done one.


I'm not sure what that means. If the software blur isn't done right, it doesn't look like bokeh, just some kind of blur.



> But to say there is a difference in softness that can not be created any other way is foolishness in my opinion.


Go back and reread what I said. I never claimed it couldn't be done. I said it takes a lot of work to get anywhere near convincing. You need to spend a lot of time with the selection tool to get everything that is the same distance away from the camera at the same blur. That's easy when you are talking a photo of an empty parking lot. You can just use a gradient out into the distance. But if you have a lot of items and a lot of different angles, you need to account for every single one. Besides that, there are many ways to create blur with software. The number of iris blades in a lens affects the bokeh, just as blur technique affects the outcome in software. Some don't look so good.

For many people, time is money. It seems like promoting the idea of spending hours at the computer for every image just to add DOF is as much of a waste as adding equipment you don't need. What's wrong with just getting the equipment that can do it in the first place if that's what you want to accomplish?



*I'm making an assumption here, but I don't think I'm off-base. Several are the people I learned from, after all, and I have a pretty good idea of how they see an image after observing my own and my fellow classmates' work being critiqued.


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## markc (Dec 24, 2006)

mysteryscribe said:
			
		

> I  have absolutely no arguement with that reasoning.
> 
> Just don't try to kid me that to get that effect you have to buy a thousand dollar lens and nothing else will do.  First of all I agree that any 1.4 1.8 or even 2.8 will do that.  So you have to crop a little instead shooting from the next county.  Sorry I just don't buy into the the fill a room full of stuff to produce one picture a week.  A proof can be softened in a few minutes and a finished image for printing in twenty minutes max.   To tell someone they can't do it any other way but to buy the expensive lens just isn't true.


I am continually amazed at how you can be reading that from my posts. The Canon 50mm/f1.8 can be had for less than $100, and is exactly what I've been using in my examples.


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## markc (Dec 24, 2006)

Mad_Gnome said:
			
		

> The question of whether or not Photoshop-created DOF works for you will be solved mainly by one question: how much is your time worth? If you're only doing one or two photographs, the extensive amount of work to recreate what a good lens can do inherently might be worth the initial money savings. If you're intending to put that much work into an extensive number of photographs...how much time will that take you? What kind of hourly rate is your time worth? Multiply those two and see if it costs the same as a 50mm f/1.8 lens, which is fully capable of creating a very narrow DOF. Or a 50mm f/1.4, for that matter. Or any of a few dozen other lenses that can recreate the same effect. Add in the cost of Photoshop itself, which retails for more than twice what my 50mm f/1.4 did. Are you still saving money?
> 
> Can Photoshop recreate the effect with a reasonable degree of success? Yes. But is it worth it when it can be created more quickly, more easily, and for less investment with the proper equipment?


Yes! Thank you. That's exactly it.


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## mysteryscribe (Dec 24, 2006)

I can see now I'm going to have to either stop trying to discuss this stuff or buy a digital camera.  I don't have that much interest in owning digital cameras of my own, so i think i need to give up commenting on digital.

I still don't think in this particular instance it is necessary to have a dslr to make an acceptable short depth of field shot, and nothing anyone has said has convinced me it is the other way.  There are just too many graphic artist who own nothing but pns cameras for me to believe you can't improvise and make it work.

As to the origninal question I suspect the 2.8 lens would make the same depth of field shot as the 2.8 on a slr.. it does on a med format vs 35mm if I remember correctly.  I am willing to concede that may not be correct.

  If that is the case, is a 2.8 depth of field unacceptable to the author.  I can remember a time when 2.8 was considered a fast lens with very poor imagine quality because it had so little depth of field at that setting.

So if you find me commenting again on any digital product or proceedure please kick me in the butt.

Otherwise I'm not changing my opinions.  I still don't think equipment is the answer to photography.  Then again I shoot with fixed lens cameras for the most part.  THAT is an opinion and the acceration rate of a brick vs a concrete block has no bearing on it.


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## markc (Dec 24, 2006)

mysteryscribe said:
			
		

> I still don't think in this particular instance it is necessary to have a dslr to make an acceptable short depth of field shot, and nothing anyone has said has convinced me it is the other way.


You can, as RMThompson's shots show. What is hard to do is get the short DOF when the subject isn't close to the camera. I'm going by data here, not experience, so if someone can post an uncropped shot from a small sensor camera showing otherwise (like at 20'), that would be cool.



> As to the origninal question I suspect the 2.8 lens would make the same depth of field shot as the 2.8 on a slr.. it does on a med format vs 35mm if I remember correctly.  I am willing to concede that may not be correct.


It is if it's on the same focal length lens. f2.8 on a 50mm lens is the same size no matter what camera it's on. The issue is that f2.8 on a 9mm lens is a lot smaller than f2.8 on an 50mm lens, even though both are considered "normal" for their sensor size and have the same field of view (the picture composition will look the same). The small sensor cameras use very small focal lengths, so even though their f-numbers are lower, the actual apertures are very small. The blur comes from the actual size of the opening, not the f-number.

F-stops are just a ratio. Diameter of aperture = focal length / f-number. To get the true aperture opening, you divide the focal length by the f-stop. f2.8 on a 50mm lens is 17.86mm wide. That's a big opening, so you get a very shallow DOF. f2.8 on a 9mm lens is 3.2mm wide. That's a lot smaller. Now a 9mm lens on a small digital will take the same looking picture as a 50mm lens will on a 5D or 35mm film camera as far as composition goes. That's not at issue. The problem is that 9mm lens has a small aperture, even though it's labeled as f2.8. The focal length is small, so the aperture is small. To get an idea of what f2.8 is like on a small sensor camera compared to a larger one, we can just see what f-stop the 50mm lens is at a 3.2mm opening. It would be just about f16, since 50mm (focal length) / 3.2mm (diameter of aperture) = f15.625 (f-number).

This would also apply to a 9mm lens on a 35mm camera or a 5D. That's why it's so hard to get shallow DOF with a wide angle lens, and why a telephoto is so good at it. The reason 9mm is important is that's the normal focal length for some of those small cameras. That's why I'm comparing it to a 50mm lens. Even something that's telephoto on those small cameras doesn't get out of the wide angle range for the bigger cameras. The A610's max focal length is only 29.2mm@f4!

Here's another way to look at it using actual numbers from the A610. At full wide and full aperture, that camera can do 7.3mm@f2.8. That's an actual aperture diameter of 2.6mm. A focal length of 7.3mm is like a 35mm lens on a film camera, so that f2.8 is like f12.5 on a larger camera using a lens with a comparable field of view, where you'll get the same composition and be standing in the same spot.

At full telephoto and full aperture, that camera can do 29.2mm@f4.1. That's an actual aperture diameter of 7.12mm. A focal length of 29.2mm is like a 140mm lens on 35mm film, so f4.1 at that focal length is like f20 on a larger camera.

Yet another way to compare is to look at the distance scales on a couple of lenses. When setting the near distance to 1m on my 50mm lens, the far distance is almost 3m at f22. On my 85mm lens, it's 1-1.2m at f22. That makes sense when you do the math. f22 on the 50mm is 2.27mm. f22 on the 85mm is 3.86mm. The smaller actual aperture size on the 50mm lens gives it more DOF.

With that in mind, would you be up for an experiment RMThompson to see if those numbers play out? I might be missing some aspect on how all this goes together. Take a picture at max aperture using the lens at *max telephoto* (29.2mm). Have someone stand in from of a tree or building that has some detail. Back up enough so that you can get at least a full head shot. Try one that's more upper torso too. A full body shot might be interesting if you have the room. I'm guessing you might have to go outside.


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## mysteryscribe (Dec 25, 2006)

I wish to say that I stand corrected,,, Which I often do... I did some reading and their indeed is a difference between a 2.8 on a small sensor camera and a larger one.  It seems the same is true with any sensor or film camera so indeed a 120 would have a shorter depth of field than a 35mm.

I suppose the reason no one ever noticed is that modern lense were marked with the depth of field indicators and we always thought the other way,  You wanted large depths so we didnt worry,

Turns out there is a math formula for depth of field by sinsor size.  If short depth of field is important to you in the camera you should go there and see what yours is each brand of camera is different.  with differences even in the line of cameras offered by the brand,

http://www.wrotniak.net/photo/tech/dof.html#NTA

So I stand corrected how well these work you can document there.  

My original thought that you just create your depth of field if a particular image needs it stands.  I still believe it is possible to creat depth of field in the few pictures most people would use it in the editing without the need of buys a camera outfit costing significantly more money.  The time vs money arguement is as valid now as I agreed that it was before.


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## markc (Dec 25, 2006)

mysteryscribe said:
			
		

> Turns out there is a math formula for depth of field by sinsor size. If short depth of field is important to you in the camera you should go there and see what yours is each brand of camera is different. with differences even in the line of cameras offered by the brand,
> 
> http://www.wrotniak.net/photo/tech/dof.html#NTA


Yeah. That's using the same concept as my numbers were, but from a different angle. It's still not the sensor size directly, but the focal length range it uses. The "M" in their formula covers that aspect, which is the focal length conversion factor between sensor sizes.



			
				mysteryscribe said:
			
		

> I suppose the reason no one ever noticed is that modern lense were marked with the depth of field indicators and we always thought the other way,  You wanted large depths so we didnt worry,
> 
> ...
> 
> My original thought that you just create your depth of field if a particular image needs it stands.  I still believe it is possible to creat depth of field in the few pictures most people would use it in the editing without the need of buys a camera outfit costing significantly more money.  The time vs money arguement is as valid now as I agreed that it was before.


I guess that goes back to how we see photography differently. I'm all for the common man, but common art leaves me cold. There are times when you want everything sharp, like with most landscapes, but for portraits and such, many people like to blur out the background. This may not have been common in your circle, but in my experience of photography, this has always been an option and a long-standing practice. Snapshot takers tend to want everything in focus, no matter what, so those small cameras can be perfect for them. For people who want to go beyond a snapshot and have some more creative control, they can be limiting. 

I agree that using software is an option, but I still think it's not a particularly effective one if you want to do more than the occasional image. If you want to do landscapes, no problem. If you want to do portraits and have control over DOF, I think people are better suited with a longer focal length lens, which unfortunately means a larger sensor.

So I guess we are in the same chapter now, if not on the same page. I think a lot of what's left is personal taste. It seems you dislike short DOF in general, and I don't like the results of software; you like to shoot with what's at hand, and I prefer more control.


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## Flash Harry (Dec 25, 2006)

Trouble is punters dont give a s**t, they just look at the product and if they like their expression or how you've caught them they're happy, its nothing to do with how the effect was created, they're not interested in lens technicalities they just want a pretty picture.


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## Don Simon (Dec 25, 2006)

That is almost certainly true in many cases, but I don't really see the relevance. The original post wasn't about commercial photography or what the punters want when you're producing prints for other people; someone specifically expressed an interest in achieving shallow DOF. They wanted to know if it could be achieved with any current fixed-lens compact digital cameras, the debate was on whether or not it could, then it turned into one on whether the more shallow DOF attainable with a fast prime could be convincingly simulated in software (and whether it's convenient to do so). Presumably 'pubius' is still interested in achieving shots with a shallow DOF, so I guess he/she cares about how the effect is created


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## mysteryscribe (Dec 25, 2006)

ZaphodB said:
			
		

> That is almost certainly true in many cases, but I don't really see the relevance. The original post wasn't about commercial photography or what the punters want when you're producing prints for other people; someone specifically expressed an interest in achieving shallow DOF. They wanted to know if it could be achieved with any current fixed-lens compact digital cameras, the debate was on whether or not it could, then it turned into one on whether the more shallow DOF attainable with a fast prime could be convincingly simulated in software (and whether it's convenient to do so). Presumably 'pubius' is still interested in achieving shots with a shallow DOF, so I guess he/she cares about how the effect is created


 
I think the pure question was is there a pns that can get sufficient lack of dof to do what it he wants. I suppose the answer is what do you want to do.

It is my opinion that it is a mole hill trying to be a mountain. The effect can be done with software. I would practice with the software to see if it is satifactory for my desires, if not and he wants short dof he may have to brush up on his math. The chart on the site I listed gives a mathmatical formula for figuring the brands of cameras and which will come the closes to a traditional film cameras. So that he can compare them roughly and make his own decission.

As for the whole depth of field thing, it leaves me cold. The only time I was really concerned with depth of field was when it was a necessary element of what I was shooting. Ie a three row group in the front of a church. Me and all my photographer friends would agree that you wanted as much dof field as possible. Now that might leave some people cold but its not art it's reality.

If I were shooting a shot outside or even in a large room and the background was going to be distracting. I would fuzz it out when I can. It wasn't a big artist issue for me, or my friends, who all were also in the business.  We just did what we had to do with Dof...  


As for now, If I shoot a picture and get it winds up on a digital file and if the background is distracting, I'll just get rid of it. For me it's the end result. That might seem counter to my using old cameras and trying to do everything in the camera but hey I have always painted out things which bothered me on the photograph. So software is no more to me than an easier touch up brush.

And Mark you are right, we  look at photography very differently.  That's about the kindest way to put it for both of us.


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## Don Simon (Dec 25, 2006)

mysteryscribe said:
			
		

> As for the whole depth of field thing, it leaves me cold. The only time I was really concerned with depth of field was when it was a necessary element of what I was shooting. Ie a three row group in the front of a church. Me and all my photographer friends would agree that you wanted as much dof field as possible. Now that might leave some people cold but its not art it's reality.
> 
> If I were shooting a shot outside or even in a large room and the background was going to be distracting. I would fuzz it out when I can. It wasn't a big artist issue for me, or my friends, who all were also in the business.  We just did what we had to do with Dof...


I'm not sure I understand what you're saying here (I'm feeling a bit slow tonight). Are you saying that controlling depth of field was never important  for you beyond making sure the subject or subjects were in acceptable focus? In which case you might as well have a fixed (small) aperture as well as fixed lens. Or are you only saying that you never felt the need to have _very_ shallow depth of field? Or something else?

Also the bit about being able to do the effect in software still seems questionable to me. In fact I'd say it can't be done so much as _simulated_. That is certainly possible. It is also possible in PS to paste someone in front of a building in a different shot... but it takes time and effort to do it convincingly, if you both lived nearby would it not be easier to actually take a shot of them in front of that building? So you can replicate the effect of shallow depth of field... but convincingly, quickly and consistently? I know we all have different ideas of photography but I do think there's a reason people talk about the quality of 'bokeh' beyond trying to justify buying extra gear. For me it's not a question of needing very expensive or specialist equipment. It's more about asking yourself, if you want to take shots with  fairly shallow depth of field on a regular basis and it's going to take you quite some time to _convincingly_ simulate the effect, would it really be that wasteful or pointless to go out and spend under $50 on an old SLR and prime?

By the way I'm happy to be proved wrong (sometimes!), and if anyone's still interested in trying to simulate the effect in software I thought I might take a couple of shots of a more tricky scene with and without shallow DOF.

Finally, as it's just gone midnight here, I hope you all had a good Christmas! And RIP James Brown.


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## mysteryscribe (Dec 25, 2006)

*I'm not sure I understand what you're saying here (I'm feeling a bit slow tonight). Are you saying that controlling depth of field was never important for you beyond making sure the subject or subjects were in acceptable focus? In which case you might as well have a fixed (small) aperture as well as fixed lens. Or are you only saying that you never felt the need to have very shallow depth of field? Or something else?*

Not sure what you dont understand. In my mind the purpose of apperture is to properly expose the picture but in conjunction with the shutter speed.

Given the choice I would use as small apperture as possible when shooting groups of staggered people. Long depth of field being desirable.

Given the choice I would use a large apperture when shooting a person or thing where I needed to fuzz out the background.. I e short depth of field. All things relative to the shot. I in no way see how this is equatable to a fixed aperture lens. It seems to me that it is the opposite.

*would it really be that wasteful or pointless to go out and spend under $50 on an old SLR and prime?*


The discussion was not about a fifty dollar slr,  It was about a few hundred dollar pns or a dslr seemingly to make that one type shot.

*By the way I'm happy to be proved wrong (sometimes!), and if anyone's still interested in trying to simulate the effect in software I thought I might take a couple of shots of a more tricky scene with and without shallow DOF.*


Please do I would be thrilled to take a shot at it. But to be fair, we should do a blind test. You shoot one with everything in focus post it. Then shoot one from the same spot with short depth of field and DON'T post it. Let whoever wants work the one you post then send it to you. You post all of them in the general gallery and see which one the people here think is better of if there is any significant difference. Win or lose if it makes people better informed it will be a win win..


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## ftops (Dec 26, 2006)

it alllllll depends on the lense.  and remember, the further you focus on something, the deeper the depth of field is going to be, and the higher the aperture will have to be set at.  the smallest ive heard of is a lense for my olympus om-pc, which is just a 50mm lense with a 1:1 ratio.

each lense is different: an f-stop of 2.8 is not a universal thing, and ive never found p&s to be all that great when it comes to shallow dop.


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## Don Simon (Dec 26, 2006)

mysteryscribe said:
			
		

> Not sure what you dont understand. In my mind the purpose of apperture is to properly expose the picture but in conjunction with the shutter speed.
> 
> Given the choice I would use as small apperture as possible when shooting groups of staggered people. Long depth of field being desirable.
> 
> Given the choice I would use a large apperture when shooting a person or thing where I needed to fuzz out the background.. I e short depth of field. All things relative to the shot. I in no way see how this is equatable to a fixed aperture lens. It seems to me that it is the opposite.


I guess what I don't understand is the idea of aperture and shutter speed being there simply to "properly expose the picture", and creative control having no bearing. I'm not talking about high art here, just a level of control that goes beyond 'proper exposure', for example maybe using a slow shutter speed to emphasise blurring in motion, or (in the case of aperture) deciding to control the depth of field. For me controlling depth of field goes well beyond "fuzzing out the background". That may well be the case with a standard portrait. But a lot of shots don't simply consist of a subject and a background. They may contain different subjects and elements, at different positions and distances. Sometimes you want a graduation in the depth of field, not simply "subject in focus, background fuzzy". I.e. you would not necessarily want that group of staggered people all in sharp focus. Of course it is all relative to the shot, what else would it be?



			
				mysteryscribe said:
			
		

> The discussion was not about a fifty dollar slr,  It was about a few hundred dollar pns or a dslr seemingly to make that one type shot.


But was it? I'm just skimming through the thread here but it's mainly been yourself who was talking about thousand dollar gear. Earlier in the post I said I would do the shot with a film SLR if not a digital one, and no one's yet suggested that film isn't an option here, so why is the debate not about a fifty dollar slr, and why is it about a thousand dollar one?


As for the DOF/software comparison thing, good idea about only posting the one shot. I'm just heading out and hopefully will be able to post something later on.


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## mysteryscribe (Dec 26, 2006)

*I guess what I don't understand is the idea of aperture and shutter speed being there simply to "properly expose the picture", and creative control having no bearing.*

That is not at all what I said.  I said this.

_*Not sure what you dont understand. In my mind the purpose of apperture is to properly expose the picture but in conjunction with the shutter speed.

Given the choice I would use as small apperture as possible when shooting groups of staggered people. Long depth of field being desirable.

Given the choice I would use a large apperture when shooting a person or thing where I needed to fuzz out the background.. I e short depth of field. All things relative to the shot. I in no way see how this is equatable to a fixed aperture lens. It seems to me that it is the opposite.*_

_This comment began in reference to you suggesting that I was suggesting the equivalent of a fixed aperture camera and dof the same in all cases not a study of the effect of shutter speed on motion._

_I think I covered that aperture was more than contol of exposure it is also for more than contol of dof.  _


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## Don Simon (Dec 26, 2006)

I thought I was asking rather than suggesting 

As for control of DOF, I'm sure you did cover it but that wasn't the impression I got from reading the post. You said, "The only time I was really concerned with depth of field was when it was a necessary element of what I was shooting". You gave a couple of examples and talked about fuzzing out the background when it's distracting. I just can't really relate to that. The appropriate depth of field concerns me as part of _every_ shot, to me it's a basic element of composition which I always consider along with all the other elements. I got the impression from your post that you didn't share this view.


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## mysteryscribe (Dec 26, 2006)

Then I suppose we will have to agree to disagree. My main consern when I compose a photograph are the elements in the photograph. All the rest is just how to make it work. For me depth of field is only a consideration in how to make the compostion work. 

It is absolutely secondary to the composition of the shot as far as I'm concerned. I can't imagine it being a primary concern for me under any circumstances, except as an example of what can be done with aperture. That might just be me but I don't think in those terms.

I think I want a shot of this object but I dont want that school building in the background so fuzz it. I don't think gee I want to make a fuzzy picture with an object of somekind in the center let me go find one. People the same way. If I'm shooting a portrait and had my druthers I would always shoot it small aperture but sometimes you can't. It just isn't a primary consideration for me as it seems to be for some people
So lets just agree to disagree on it's importance. 

That still doesn't change the basics. I can do what I (maybe not you) want with software, when it isn't possible in the hardware. So if I can do it, so can anyone else if they are patient and take their time with it. Soft focus, no matter how it is created, is still soft focus. Now that is a personal opinion but it isn't something that I am likely to change . I'm sure your belief ,that you can't create the same effect with software that you can with hardware, is likely to change either. 

As for time vs money, I will spend ten minutes to save a grand most any day. I will also spend it to save an image I am otherwise happy with. Maybe that is just me, but it's how I started and how I plan to end. It is why in the old days I learned to retouch. Sometimes there isn't a lens soft enough to hide acne scars and a paintbrush is your only friend. Now it's a cloning tool.


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## Don Simon (Dec 26, 2006)

mysteryscribe said:
			
		

> I think I want a shot of this object but I dont want that school building in the background so fuzz it. I don't think gee I want to make a fuzzy picture with an object of somekind in the center let me go find one.


Nor do I. I often find shallow depth of field very effective for certain shots, that doesn't mean I specifically set out looking for a shot on which I can use shallow depth of field. It's not a more important concern than others, but to me it's neither more or less important than composition, because it is _part_ of composition. But I agree that we should agree to disagree 

As for the soft focus in software thing, no I don't think either of us change our opinions, but I'm willing to be pleasantly surprised by what others can do with software so I'll try to get some shots uploaded soon.



			
				mysteryscribe said:
			
		

> As for time vs money, I will spend ten minutes to save a grand most any day. I will also spend it to save an image I am otherwise happy with. Maybe that is just me, but it's how I started and how I plan to end. It is why in the old days I learned to retouch.


Now I know we're not going to agree on everything, but surely we can agree that it is really _not_ necessary to spend a grand to take a shot with shallow depth of field without using software. That $50 film SLR and prime still seems like a perfectly good option to me. Yes I would spend ten minutes to save $50 too, but ten minutes and ten minutes and ten minutes adds up.


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## mysteryscribe (Dec 26, 2006)

Well it seems that according to at least a few folks here if you want to achieve short depth of field in *digital* which was the original origin of the discussion was.  I film I am sure you don't need to do anything but get a large aperture lens on any camera slr or folder or view camera it is all the same as far as I know if you get one large enough you get depth of field control.  Of course they will tell you that it is the same with digital but to get the large enough aperture you need the 1000 camera.

Most people dont want to invest even 40 bucks in a film camera these days.  Which is why I bought a nice slr body for 30 bucks and was the only one interested.


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## ftops (Dec 26, 2006)

i, on the contrary, focus on a picture that fits into a pre-desired depth of field.  it simply puts the focus on what i want it to be on, and not everything thats going on in the shot.

now, if im taking a picture of a landscape, or maybe a series of flags or structures that are at extremely varying focusing distances, ill change the aperture accordingly.

another advantage of a lower aperture (and essentially shallower depth of field) is faster shutter speeds, which usually results in sharper images.


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## pubius (Jan 4, 2007)

whoa. this got to be a long discussion, a long multi-faceted discussion. thanks to all that helped out with ideas. i was still trying to stick within the confines of what i had originally proposed, a digital p&s that can achieve the shortest focal length.

as far as using photoshop to create a false short focal length goes, i have no doubt that i could do that. in fact, i've done it, professionally, countless times. but that takes a serious amount of time. and anyone that says otherwise is doing a questionable job at it.

so, i'd rather avoid that if at all possible.

i think i got some pretty good info from everyone though.
so thanks again.


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## Mohain (Jan 5, 2007)

I must admit to not reading all of the thread (bad me) and sorry if this has been said before (I had a quick scan and could see mention of it) but the *             Sony DSC-R1* has an APS sized sensor and f2.8 at the wide end and f4.8 at the tele end of the zoom so you should be able to get a pretty shallow DOF with that.

Anyway, sorry for the interruption, carry on ...


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