# Using Manual Mode vs Av mode



## darich (Nov 10, 2005)

I recently bought a book about exposure in photographs. In the book, which contains some stunning and well exposed shots, the photographer said that he uses "M" mode all the time. He sets the aperture manually, then adjusts the shutter speed until the camera tells him the exposure is right.
I totally understand how that works and the relationship between aperture and exposure.
However, am i missing something by not understanding the difference between his method and Av?
When using Av doesn't the camera adjust the shutter speed automatically to suit the manually chosen aperture? If so, then it's quicker than using "M" mode.
My understanding is the same with Tv mode except in this mode, the photographer manually sets the exposure and the camera adjusts the aperture automatically.
Can anyone explain to me why he, or any photographer, would use "M" mode when not looking to alter the exposure of an image?


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## thebeginning (Nov 10, 2005)

i only use M if I want to do creative expsosing.  otherwise i use Av. It's basically so that you can read the meter, then choose how you want to expose the scene.  When in Av, you may meter it how you want, but when you compose it it reads something else, losing the previous meter reading.  in M mode you can just meter the scene until you get it how you want, then compose, and you wont have to worry about your setting changing.


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## darich (Nov 10, 2005)

So the "M" mode is really only if you want to manually adjust the exposure to deliberately over or underexpose an image?
I guess it could be used for bracketing by quickly changing the exposure between shots?


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## hobbes28 (Nov 10, 2005)

Not always.  I shoot in Manual mode all of the time for a few reasons.  One reason is that it keeps me on my toes and shooting like I learned..without any meters or automatic frills.  The other reason is that you can control your contrast and DOF in different settings more with the manual mode (at least the one on the D70) because Av seems to put Lo or Hi up a lot when Manually, it can be adjusted even further.  eg. Full sunlight f1.8 and a shutter speed of 1/8000 which in Av mode at 1.8 would say Hi...and over expose while trying to shoot at 1/4000.


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## thebeginning (Nov 10, 2005)

well yes, but you can use it to make sure the camera doesnt change exposure also.  like if you want to expose for a particular part of a scene, you meter accordingly, then put it on M with those settings to make sure it doesnt change because of other things in the scene that would change the meter reading. that sounded confusing....like say you were photographing a person on white snow and you want the person in the right of the frame. on av mode, if you put the person on the side, the meter would meter the snow, underexposing the scene. if you meter the person the put it on M with those settings, you dont have to worry about the settings changing to meter the snow.


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## sparky (Nov 10, 2005)

darich said:
			
		

> I recently bought a book about exposure in photographs. In the book, which contains some stunning and well exposed shots, the photographer said that he uses "M" mode all the time. He sets the aperture manually, then adjusts the shutter speed until the camera tells him the exposure is right.
> I totally understand how that works and the relationship between aperture and exposure.
> However, am i missing something by not understanding the difference between his method and Av?
> When using Av doesn't the camera adjust the shutter speed automatically to suit the manually chosen aperture? If so, then it's quicker than using "M" mode.
> ...



The answer is that there is no reason for him to use M mode. Some photographers seem to be of the opinion that because they use M mode over Av/Tv modes, they are doing something different, something better. Of course they are just doing exactly the same thing as the priority modes, but taking longer to do it!

You are correct in that M is most useful for when you want to alter the exposure from that which the camera suggests (although simply changing the EV is usually a quicker way to do this.)


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## thebeginning (Nov 10, 2005)

sparky said:
			
		

> The answer is that there is no reason for him to use M mode. Some photographers seem to be of the opinion that because they use M mode over Av/Tv modes, they are doing something different, something better. Of course they are just doing exactly the same thing as the priority modes, but taking longer to do it!
> 
> You are correct in that M is most useful for when you want to alter the exposure from that which the camera suggests (*although simply changing the EV is usually a quicker way to do this*.)


 
yep.  there's more of a point to use M when shooting film than with digital too, in my opinion.  with digital you can just bracket alot or bracket a little (or not at all) and shoot RAW.


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## JamesD (Nov 10, 2005)

This might shed some light on it... although it appears to be keyed to a particular camera. The basic information still applies.

http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/950/aperture-priority.html


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## sparky (Nov 10, 2005)

JamesD, I don't think the OP was suggesting that he didn't know how to use either of the modes, but was curious as to to why the photography was using M mode then simply adjusting the settings until he got 0 EV when there is a much easier mode to use for this purpose.


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## danalec99 (Nov 10, 2005)

M is my preferred mode. 

 But when it comes to assignments like weddings, when you have multiple cameras on your body and when the lighting changes every often, it is the Av mode that I rely on. Lock the focus, recompose, fire and move on.

Try all the modes and pick _your_ comfort zone.


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## danalec99 (Nov 10, 2005)

thebeginning said:
			
		

> like say you were photographing a person on white snow and you want the person in the right of the frame. on av mode, if you put the *person on the side*, the meter would meter the snow, underexposing the scene. if you meter the person the put it on M with those settings, you dont have to worry about the settings changing to meter the snow.


Lock the focus on the person, recompose, you will be exposing for the person, in Av.


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## photogoddess (Nov 10, 2005)

I generally use Av mode but do switch over to full manual on occassion. Some scenes just a little more control or tweaking that you only get with manual mode. As Hobbes said, it really does make you think about the shot before you take it. :mrgreen:


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## thebeginning (Nov 10, 2005)

danalec99 said:
			
		

> Lock the focus on the person, recompose, you will be exposing for the person, in Av.


 

so when you lock the focus, the exposure reading stays the same?


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## danalec99 (Nov 10, 2005)

thebeginning said:
			
		

> so when you lock the focus, the exposure reading stays the same?


Yes.
 In order to reconfirm, I tested before writing that post.

Dan, do a test with a table lamp or something bright when you get time.


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## thebeginning (Nov 10, 2005)

i just tried it, i never even knew that worked. awesome :thumbsup:

haha, thanks!


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## JamesD (Nov 10, 2005)

sparky said:
			
		

> JamesD, I don't think the OP was suggesting that he didn't know how to use either of the modes, but was curious as to to why the photography was using M mode then simply adjusting the settings until he got 0 EV when there is a much easier mode to use for this purpose.




Mmm, yes. I'll say it then: control of depth of field, as well as control of exposure. AV is semi-automatic. Set the aperture for the DOF you want, then let the camera control the shutter speed to get correct exposure. If necessary, manually adjust the exposure up or down.

I generally use M, unless I'm in a situation where I need to shoot quickly. Then, I usually use TV, since I'm typically shooting something like my company's football team in action... I want to be sure I use a fast shutter speed to catch the action, and DOF isn't quite as important. If I were shooting something where I wanted to control DOF and stop-motion weren't so important (a wedding, perhaps), I'd use AV.

That's how I use it. Maybe right, maybe wrong, but it works for me, and as I understand it, that's the general theory behind the two semi-automatic modes.


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## thebeginning (Nov 10, 2005)

for me, shutter speed always comes first.  however, i dislike using Tv. If i need high shutter speeds i just change the settings and shoot in Av. Usually i like a pretty shallow DoF anyway, so they coincide well.  For set shots I often use M. otherwise i use Av.


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## Marctwo (Nov 11, 2005)

Don't you guys use P? :meh: 

I think it's best to take the time getting comfortable with all the modes to the point where you can view any scene and shoot just as easily with AV, TV, M-AV or M-TV.

There comes a time for all of them.


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## jstuedle (Nov 11, 2005)

I'm old fashioned. My camera has all the bells and whistles, but I have shot Manual or Aperture Priority forever. To me, it feels like I give up too much control with any of the program modes and I just never liked shutter priority mode.


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## danalec99 (Nov 11, 2005)

Marctwo said:
			
		

> Don't you guys use P? :meh:


As in 'Professional' mode, huh! 

Actually there is this prominent wedding photographer here named Joe Buissink who shoots in P mode whenever there is ample available light.


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## JamesD (Nov 11, 2005)

I found another reason for using AV, rather than full auto (Manual would work, but loses the "semi-automatic" shooting--ha ha! I made a pun!  :mrgreen: )

A buddy and I were working last night while he showed me some things about flash photography, which I'd never really used before because I never really understood it--and I still really don't, but I'm getting there.

Basically, what he proved to me is that, when using flash, shutter speed controls exposure of the background, while aperture controls exposure of the subject. Based on the roll of test shots we did last night, this is a very powerful tool: the camera automatically sets exposure for the background, keeping that exposure the same by changing shutter speed while the photographer adjusts aperture. Meanwhile, the photographer manually sets exposure for the subject by changing the aperture to expose correctly for the flash being used. Very cool! I might have to start using this, instead of using manual all the time...

I really do learn someting new about photography every day... one reason why it's so much fun.


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## Patrick (Nov 11, 2005)

JamesD said:
			
		

> I found another reason for using AV, rather than full auto (Manual would work, but loses the "semi-automatic" shooting--ha ha! I made a pun! :mrgreen: )
> 
> A buddy and I were working last night while he showed me some things about flash photography, which I'd never really used before because I never really understood it--and I still really don't, but I'm getting there.
> 
> ...


 
For me it's more of which metering mode I use. I very seldom use manual mode. Mostly Pm or "A". I find myself switching to the "spot" meter more and more for creativity and to have more control over the image. Until you learn how to use your light meter, does what mode you use really make a difference? Other than DOF, freezing the action or blurring it?

I would say learn to use your light meter first and fully understand it before moving to manual mode.


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