Do UV Filters Degrade Image Quality?

[Mando327]

Hey Guys,

I have Canon's 20D, 24-70mm 2.8L and 70-200mm 2.8L, and I have been wondering if UV (or protective) filters degrade image quality. I bought two Canon UV filters (on their way) for my lenses, but I'm still hesitant. The two lenses come with hoods. Are hoods good enough, or would you still recommend putting the filters on. I just don't want crappier pictures after dropping a grand on each lens, if you can understand where i'm coming from.

Thanks in advance,

Armando

[92135011]

yes...its an extra piece of glass with air in between

[Lionheart]

Hey Guys,

I have Canon's 20D, 24-70mm 2.8L and 70-200mm 2.8L, and I have been wondering if UV (or protective) filters degrade image quality. I bought two Canon UV filters (on their way) for my lenses, but I'm still hesitant. The two lenses come with hoods. Are hoods good enough, or would you still recommend putting the filters on. I just don't want crappier pictures after dropping a grand on each lens, if you can understand where i'm coming from.

Thanks in advance,

Armando

Any filter, I don't care who makes it, will alter the image quality. The real issue is, how much difference does it make? That's what you pay extra for with the big name filters. I've been shooting without filters on my current gear since my original gear got stolen in 2002 just because I'm somewhat loathe to spend the buko bucks on the B&W filters that got stolen with my equipment over 2 years ago. Does it make a visible difference? I'll have to test it this weekend, and I promise to have posts here by tomorrow.
Leon

[92135011]

The thing about protective filters depends on your lens.
If you have a $150 lens, then probably a $50 filter does not justify. The nice B&W filters, I have read, are multicoated and an anti scratch coating as well. The multicoat serves to prevent ghosting and flare. They might also have better quality control, but maybe not. If the lens of question isnt a very good one, then it would probably flare anyways, so maybe a cheaper filter wouldnt make a difference. Maybe the resolution and flatness of field isnt as good and then a really good filter woudnt make any difference again. Plus, would you buy $50 insurance for something that is worth only 1.5x-2x of the insurance (bought used)?

[Lionheart]

Here's an early test comparison. Shot at ISO 400, Bogen/Manfrotto tripod, Large jpg resolution, 1D MkII, 70-200 f2.8L IS, at f8. First two are already cropped to about 20% of original and are before zooming in on the alarm sticker on the window. I used a Canon UV filter for this test.
Enjoy-btw, I really couldn't tell a difference until I really zoomed in, and then I really had to squint to see any differences.

[Michael Fanelli]

Here's an early test comparison. Shot at ISO 400, Bogen/Manfrotto tripod, Large jpg resolution, 1D MkII, 70-200 f2.8L IS, at f8. First two are already cropped to about 20% of original and are before zooming in on the alarm sticker on the window. I used a Canon UV filter for this test.
Enjoy-btw, I really couldn't tell a difference until I really zoomed in, and then I really had to squint to see any differences.

One of the major problems with filters is that the extra glass helps produce flare and reflections, something that occurs only in certain circumstances. These images don't seem to be the type for that.

[Lionheart]

One of the major problems with filters is that the extra glass helps produce flare and reflections, something that occurs only in certain circumstances. These images don't seem to be the type for that.

Like shooting into the sun perhaps? I'll try sunrise shots tomorrow morning if I can get up on time ;)

[Mando327]

Thank you Lionheart for taking the time to shoot and post the pictures. There is a "less sharp" "phenomenon" here. Would you be able Lionheart to post the original picture here except reduced in size? In your opinion, Lionheart, is this "less sharp" "phenomenon" negligeble?
BTW, how in did you post your pictures here? I click on the yellow icon with the mountain and it tells me "Enter the text to be formatted". Does this happen to you too?

Thanks,

Mando

[Lionheart]

I'll try later tonight. I'm on my laptop at an office party right now and the originals are on my desktop computer at home.
Leon

[92135011]

But also as I said, you have another glass-air surface
Its not just the flare. This is why many lenses incorporate aspherical elements to correct for abberations on lenses with many elements/groups.

[Lionheart]

Thank you Lionheart for taking the time to shoot and post the pictures. There is a "less sharp" "phenomenon" here. Would you be able Lionheart to post the original picture here except reduced in size? In your opinion, Lionheart, is this "less sharp" "phenomenon" negligeble?
BTW, how in did you post your pictures here? I click on the yellow icon with the mountain and it tells me "Enter the text to be formatted". Does this happen to you too?

Thanks,

Mando

Hi Mando:
I use the upload photos button below the text box in the section marked "Additional Options". The mountain icon is for posting a link to a picture residing on a website other this one. Here's those pics I promised. I find that the filter tends to add flare/ghosting slightly. The colors are less saturated, but very slightly so.

[Mando327]

Wow....there is a big difference....to me at least...Thanks! I will now only be using my protective filters for the beach or in rough terrain only.

Thanks,

Mando