# Must-Have Filters?



## Luna (May 20, 2008)

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## jlykins (May 20, 2008)

I really like my GND filter. It helps me get the longer exposures on bright days.


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## Alpha (May 20, 2008)

ND filter set
CPL
UV, only for protection, not to shoot through

for film I keep an assortment of colored filters handy:
25, 29, and 89 reds
orange, green, yellow, and blue

Had my eye on a Singh Ray Vari-ND for a while. mmmmmmm.


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## stabo (May 20, 2008)

Alpha said:


> ND filter set
> CPL
> UV, only for protection, not to shoot through
> 
> ...


Why would you not shoot through with a UV?  only have my camera a few weeks,i leave the UV filter on the whole time.


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## Garbz (May 20, 2008)

Unless you have a very good UV filter (Hoya SHMC, B+W or some equivalent good one) you typically suffer a quality hit. 

Even with the top of the line filters if you shoot into a flaring light source like the sun or a street lamp, it'll cause ghosting.

I would agree with Alpha's list and add a Hoya RM72 Infrared filter to the list, but then i'm a sucker for the effect and shoot infrared film on occasion too.


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## Alfred D. (May 20, 2008)

Alpha said:


> ND filter set
> CPL


Ageed.


> UV, only for protection, not to shoot through


Uh-oh: UV filter only for situations where there is excess UV light to be filtered. If there isn't, don't use it.


> for film I keep an assortment of colored filters handy:
> 25, 29, and 89 reds
> orange, green, yellow, and blue


Only for B/W film.
Color negatives or slides will end up as scans in CS3 anyway...


> Had my eye on a Singh Ray Vari-ND for a while. mmmmmmm.


Could be fun if you're into the long exposure/tripod game. Please demo it for us when you get it. 


> Originally Posted by *Garbz*
> Unless you have a very good UV filter (Hoya SHMC, B+W or some equivalent good one) you typically suffer a quality hit.
> 
> Even with the top of the line filters if you shoot into a flaring light source like the sun or a street lamp, it'll cause ghosting.


_All_ filters, even the most expensive ones, share one weak spot: they have 2 sides, front and back. Both are refracting zones of course, whichever way you cut it. Thus increasing flare, focal softness, and chromatic aberration.

Use filters when you need them. But maybe even more important: _don't_ use them when you _don't_ need them!


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## TamiyaGuy (May 21, 2008)

I would say an ND filter is a good investment, especially if you like river photos in daylight. A UV filter is pretty good as well for cutting down the haze in landscape photos, although I heard somewhere that a polariser does that as well. Those are really the "main" filters, there are tons to choose from.

However, like Alfred D said, filters will degrade image quality, there's no two ways about it. It's just finding a comprimise between total image quality and the effects of various filters. Good luck!


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## AndrewG (May 21, 2008)

Skylight for protection, polarizer and orange-for b&w. All Hoya.


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## Garbz (May 21, 2008)

Alfred D. said:


> Use filters when you need them. But maybe even more important: _don't_ use them when you _don't_ need them!



I think I've said it before but a flat piece of glass doesn't cause CA, especially optical glass. That is a function of glass that bends light only. Anyway I agree on all the other points, especially the flare. Regardless of how good optical coating is a filter is a flat face and will ghost a light source. Proved that well and truly with Hoya's top filters, and cheap filters here: http://www.thephotoforum.com/forum/showthread.php?t=100830

I will disagree on principle though. A $100 filter is cheaper to replace than the aspherical front element of my 28-70 f/2.8. I've been in a situation where a filter has taken the full force of a cliff face before (cheaper lens though), and shattered, so unless I am using a tripod and shooting into something that will cause flare problems, my UV / Protection filters stay on at all times.


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## Battou (May 21, 2008)

Luna said:


> What are some must-have filters in your opinion?
> 
> I just got a circular polarizing filter and I love it! I can't believe the difference that it makes, particularly to the sky. I have been obsessed with taking before (without the filter) and after (with) photos of clouds.  I also got a six-pointed start filter, just for fun. I know it's not necesary but it's fun to play around with. I plan to get a UV filter soon for general lens protection. Are there any others that I should consider?


  I have a crossthatch filter...I'm just looking for an excuse to use it :lmao: as well as a metric butt ton of UV Filters.

It's alredy been covered but, If you are planning on doing any B&W, you should invest in a good set of BW filters.


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## pm63 (May 21, 2008)

If anyone could answer any of these, it would be great:

So is it a good idea to leave on a UV filter all the time for protection? As Garbz said, it would be tragic to break/scratch the front element of your lens.

Also, how can you tell when there will be ghosting due to your UV filter, and when are you 'supposed' to use your UV, i.e. what would be an example of a situation where there is lots of unwanted UV light?

Is it true that you should leave on a polariser for most outdoor shots, just to increase the colour saturation?

And I'd love a good ND grad, but they're so expensive


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## Alfred D. (May 21, 2008)

pm63 said:


> So is it a good idea to leave on a UV filter all the time for protection? As Garbz said, it would be tragic to break/scratch the front element of your lens.


I don't agree with Garbz here. Leaving the UV filter on when there is no excess UV light to be filtered puts an extra barrier &#8211; with 2 refracting sides &#8211; in front of the lens. That can only do one thing: degrade the image.
For lens _protection_ I use a lens cap, which was designed to do precisely that, and a lens hood (_never_ shoot without a hood!).
You don't use a screwdriver to hammer in nails either, do you?


> Also, how can you tell when there will be ghosting due to your UV filter, and when are you 'supposed' to use your UV, i.e. what would be an example of a situation where there is lots of unwanted UV light?


Use a UV filter (_only_) when there is an excess of UV light. There is an excess UV light at altitude (over 3,000 feet), in the desert and savannah, at the beach, at sea, and in snowscapes. If you're not in any of these circumstances there is no excess UV light to be filtered. So use a UV filter only in _those_ situations. Not in others.


> Is it true that you should leave on a polariser for most outdoor shots, just to increase the colour saturation?


No.
Firstly, you must _want_ that colour saturation (in the sky more than anywhere else) in that particular image. Secondly, the lens axis angle in relation to the sun determines whether or not the light _can_ be polarized, and by how much. Thirdly, polarizing slows down your available shutter speeds by up to 2,5 stops. You will probably need a tripod.

Important: polarizers and wide angle lenses don't match! You'll get blotchy skies!



> And I'd love a good ND grad, but they're so expensive


An UNgraduated ND filter is more useful. It enables you to slow down your shutter speeds, or open up your aperture (for more selective DoF), by several stops.
Instead of using an ND grad you'll get better results with HDRI.


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## pm63 (May 21, 2008)

Thanks for the reply Alfred.



> For lens protection I use a lens cap, which was designed to do precisely that, and a lens hood (never shoot without a hood!).



The thing with that is that when you're walking around the city, stopping to take photos every few seconds, it becomes very impractical to keep taking the lens cap on/off. Also, why always shoot with a hood? I thought they were only for when there is a light source close you the edge of your frame that could potentially spoil the photo, or when other excess light can enter? And even if you do leave it on, there is still a chance for your lens to get scratched.



> the lens axis angle in relation to the sun determines whether or not the light can be polarized, and by how much



I heard that a polariser works best at 90 degrees to the sun, is this true?



> An UNgraduated ND filter is more useful.
> Instead of using an ND grad you'll get better results with HDRI.



It depends on what you want. I find myself in many landscape situations where my camera cannot capture the whole dynamic range of the scene because the sun is too bright, hence the need to an ND grad. I don't want to use HDR because it gives a very specific effect, I like the "single exposure" look.


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## zapman29 (May 21, 2008)

every place i have been has always said to keep a UV on it.. so i have on all my lens then use a cp..


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## Alpha (May 21, 2008)

Garbz said:


> I think I've said it before but a flat piece of glass doesn't cause CA, especially optical glass. That is a function of glass that bends light only.



I don't think this is entirely true. According to Snell's law, the speed and wavelength of light also change upon refraction. Whether or not that change occurs differentially with respect to various wavelengths of incident light I don't know, but if it did, you'd get CA.


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## Alfred D. (May 21, 2008)

pm63 said:


> The thing with that is that when you're walking around the city, stopping to take photos every few seconds, it becomes very impractical to keep taking the lens cap on/off.


So _don't_! Anyway, _I_ don't, in those circumstances. A lens hood is sufficient protection provided you don't swing your camera around like a slingshot.
Bottomline: the lens cap is on when the camera is switched off, and the lens cap is off when the camera is switched on.


> Also, why always shoot with a hood? I thought they were only for when there is a light source close you the edge of your frame that could potentially spoil the photo, or when other excess light can enter?


"Other excess light" can enter your lens much more easily without a lens hood. There is stray light everywhere. More so if the humidity level is relatively high.
You get generally 'cleaner' exposures with the lens hood on.


> And even if you do leave it on, there is still a chance for your lens to get scratched.


Only if you really try and do stupid things.


> I heard that a polariser works best at 90 degrees to the sun, is this true?


Correct. At right angles the effect is max. The greater the deviation from that right angle, the lesser the polarizing effect.
Which also explains why wide angle lenses don't work with polarizers.


> It depends on what you want. I find myself in many landscape situations where my camera cannot capture the whole dynamic range of the scene because the sun is too bright, hence the need to an ND grad. I don't want to use HDR because it gives a very specific effect, I like the "single exposure" look.


If HDR results in a 'multi exposure look' that is because the editor made it so. In that case he/she has willfully 'overdone' the effect (par for the course, BTW).
The point of HDR is that you can make it look any way you want. Which you cannot with a single exposure.

Have fun!


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## Mystwalker (May 21, 2008)

I do not see any distortion when using a UV filter so I keep it on lens full-time.

But then I'm not selling my services and do not look at every pixel.

It's a balance between, "perfect IQ" and "protecting front element of lens".

I'm willing to sacrifice a bit of former to increase latter a whee bit.  A pro probably think the reverse.


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## Alfred D. (May 21, 2008)

Mystwalker said:


> I do not see any distortion when using a UV filter so I keep it on lens full-time.


And you never _will_ see a difference unless you shoot the same scene both with and without a UV filter and then put both images up side-by-side on your screen.


> But then I'm not selling my services and do not look at every pixel.
> 
> It's a balance between, "perfect IQ" and "protecting front element of lens".
> 
> I'm willing to sacrifice a bit of former to increase latter a whee bit.  A pro probably think the reverse.


Absolutely. It is a choice: either image quality is important to you or it isn't...


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## PhotoDonkey (May 21, 2008)

For the most part I keep my UV filter on at all times, but if I find I'm getting ghosting, I will take it off and be extra-careful.

I want to get a hood for my lens, but I've had a hard time determining what kind to get.

I have 2 Canon 58mm (diameter) lenses.  Can I get away with a single hood for both, or does canon manufacture hoods for specific models of lenses?


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## bhop (May 21, 2008)

The only real "Must-Haves" for me is a polarizer and a neutral density for when I need to cut back on light.


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## Alfred D. (May 21, 2008)

PhotoDonkey said:


> For the most part I keep my UV filter on at all times, but if I find I'm getting ghosting, I will take it off and be extra-careful.


You will never be able to tell without comparison shots.


> I want to get a hood for my lens, but I've had a hard time determining what kind to get.
> 
> I have 2 Canon 58mm (diameter) lenses.  Can I get away with a single hood for both, or does canon manufacture hoods for specific models of lenses?


Did your lenses 'fall off a truck'? Because all lenses that I know of come complete with lens hood...
So where did yours go?


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## bhop (May 21, 2008)

Alfred D. said:


> Did your lenses 'fall off a truck'? Because all lenses that I know of come complete with lens hood...
> So where did yours go?



All of the used lenses i've bought have no hoods.  My Nikon 50mm 1.8 didn't come with a lens hood and I bought it new.


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## Mystwalker (May 21, 2008)

"L"s came with hood + carrying sack or lens bag.

Non "L" (28-135, 100macro, 50mm), no hood.

All brought from B&H, Adorama and B&H - reputable places so I doubt they are swiping the hoods


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## PhotoDonkey (May 21, 2008)

Alfred D. said:


> You will never be able to tell without comparison shots.


I'm actually speaking from an experience, not in theory.  I've taken pictures where the sun was ghosting, so I took the filters off for the shot.


> Did your lenses 'fall off a truck'? Because all lenses that I know of come complete with lens hood...
> So where did yours go?


One came with the camera, the other I purchased at Best Buy.  From what I've read, Canon doesn't include hoods with their lenses.


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## Alfred D. (May 21, 2008)

PhotoDonkey said:


> One came with the camera, the other I purchased at Best Buy.  From what I've read, Canon doesn't include hoods with their lenses.


If, as Mystwalker says, "L"s come with a hood, but non "L"s don't, then there may be a lively market in Canon hoods. I would check Ebay and some of these photo forums' market threads.
Though one hood may fit both your 58mm ø Canon lenses' diameter, it will probably not provide adequate shielding for both. Because a hood's shape and size is particularly designed for only _one_ focal length (the shortest in the case of a zoom lens). On other focal length lenses it will cause either vignetting, or provide not nearly enough shading of the lens. So that's useless.
In any case it is a better idea to have every lens complete with its own purpose-designed hood.


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## PhotoDonkey (May 21, 2008)

Thanks for the advice.  I'll look into it.  I'd definitely like to try using hoods for protection instead of filters.


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## Garbz (May 21, 2008)

Alpha said:


> I don't think this is entirely true. According to Snell's law, the speed and wavelength of light also change upon refraction. Whether or not that change occurs differentially with respect to various wavelengths of incident light I don't know, but if it did, you'd get CA.



Yeah but snells law for a straight pane of glass would mean no refraction for light incident at 90 degree, and assuming both sides of the glass are parallel (a good assumption for a good filter) if the wavelengths would spread on incidence to the first boundary, the exact inverse would happen on the incidence to the second boundary, cancelling the effect of CA, and also the effect of the refractive index. Which is why we see these filters as translucent. 

Mind you on a cheap filter where the distortion in the glass is visible as a distinct loss of sharpness in the image (those cheap nasty Hoyas for example) would imply that the glass isn't of a constant refractive index, or both boundaries aren't parallel and at that point CA would rear its ugly head.

But you wouldn't see it on that filter through all the nasty flare :lmao:


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## seabug (May 22, 2008)

I believe the must haves are the ND filters and if you have a clear horizon perhaps the ND grads.  ND filters are great to cut down light to allow for a long exposure to get that milkly appearance of water falls or water movement.   A polarizer is  great for making clouds stand out against the sky and making greens such as in a forest pop.  Polarizers are also good for shooting through windows and through water as they cut reflections. A lot of good advice.  I also have a red and yellow filter which I find useful.  You can get a lot of the filter effects though photoshop etc but there is nothing like getting it right off the hop.  Happy shooting!


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## Alfred D. (May 22, 2008)

Well, after all this jubilation it is maybe a bit sobering to also consider the trade-offs of those wonderful gadgets. Because there's always a flipside to everything.
While CPs are great for skies, and foliage, and reflections, they adversely affect reds in general and aren't flattering at all on skins.
While NDs are great to cut down light to allow for long exposures, they don't change the dynamic contrast range in a scene one bit! The mutual relationship of highlights and shadows doesn't change one iota. If your cam cannot grab the whole dynamic contrast range of a scene without an ND filter, adding one won't change that.


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## Garbz (May 22, 2008)

Alfred D. said:


> While CPs are great for skies, and foliage, and reflections, they adversely affect reds in general and aren't flattering at all on skins.



You just gave me an excellent idea. CP to completely elminate specualr highlights off skin, combined with a 720nm IR filter. This would have to be shot on film given that typical digital camera would need an exposure value of about -2 or -3 whereas you could easily get a 10 or 11 out of film.

It would create the most perfect undead and creepy look in the subject. The CP would ensure the skin is feature less and has a constant tone, and the IR filter would make it white, and the eyes black.

If only it were a sunny day. Don't mind my derailing.


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## TheBiles (Oct 10, 2010)

When do you NEED a UV filter, and what's the risk of not using one?


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## Bitter Jeweler (Oct 10, 2010)

You don't NEED one. There is no risk.
Use a lens hood for protection instead.


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## seabug (Oct 11, 2010)

A UV filter is useful for protecting your lens against dusty conditions such as sandy area when there is wind and salt water spray when at the ocean other than that you just need a lens hood.


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