Hoya Pro1 UV, CPL, and 8X ND SAMPLE IMAGES

Here it is! look at the crops and come to your own conclusions. This is intended as an image quality test on these particular filters.

Canon 30D, Canon 50mm f/1.4, ISO100, f/5.6, autofocused the "BG-E3" for the first shot, then locked into manual focus for all other shots. Straight out of the camera, remote shutter with mirror lockup.

77mm Hoya Pro1 Circular Polarizer, Hoya Pro1 UV, Hoya 8X Neutral Density

CPL + UV + 8X ND, 2.5s

I don't get it. I thought CPL is used for shooting the scenes so that the sky will pop more, not some dark object shot indoors?

The point is to see if there would be a significant drop in optical quality by using these filters and by stacking them.

I'm actually shocked in how much softer it is with just the CPL.

What camera/lens? I'm sure it's in the EXIF but I'm lazy.

fuzzybabybunny wrote in post #2568975
The point is to see if there would be a significant drop in optical quality by using these filters and by stacking them.

Don't get me wrong. I applaud your effort here for everyone's benefit... But the reality is that I'm not going to use the CPL to shoot some dark object indoors. The intended image target is a scene with the blue sky to get that pop. Now, if I see the similar tests done using the sky scene with the same results, then I'd be more than happy to be convinced. My point is simply that the results might turn out to be different if the filter is used for its INTENDED target, as opposed to UNINTENDED.

I agree, thanks for taking the time to share your results, but maybe you can also do us another favor and do some tests on subjects which are more likely in our target zones. Thanks!

SYS wrote in post #2569271
Don't get me wrong. I applaud your effort here for everyone's benefit... But the reality is that I'm not going to use the CPL to shoot some dark object indoors. The intended image target is a scene with the blue sky to get that pop. Now, if I see the similar tests done using the sky scene with the same results, then I'd be more than happy to be convinced. My point is simply that the results might turn out to be different if the filter is used for its INTENDED target, as opposed to UNINTENDED.

Oh, I'm completely sure that it will be able to make the sky pop without vignetting. But you're going to be paying a small price with the drop in image quality.

BTW, I would not recommend this filter just for the fact that it is impossible to get off the lens once it's on. I put this on my Sigma 10-20mm and I DID NOT tighten it at all. After a few minutes of just playing around with the rotating ring I went to go take it off and couldn't. I spent a good ten minutes fiddling desperately with it and it finally came off. I cannot risk a filter getting impossibly stuck in the field. It would be very aggravating if it got stuck on my 10-20mm and I needed to put it on my 30mm or something.

fuzzybabybunny wrote in post #2569365
Oh, I'm completely sure that it will be able to make the sky pop without vignetting. But you're going to be paying a small price with the drop in image quality.

BTW, I would not recommend this filter just for the fact that it is impossible to get off the lens once it's on. I put this on my Sigma 10-20mm and I DID NOT tighten it at all. After a few minutes of just playing around with the rotating ring I went to go take it off and couldn't. I spent a good ten minutes fiddling desperately with it and it finally came off. I cannot risk a filter getting impossibly stuck in the field. It would be very aggravating if it got stuck on my 10-20mm and I needed to put it on my 30mm or something.

Hmmmm... that's the first time I heard of the filter being stuck on the lens. I wonder if the same thing could happen on Canon 10-22.... Could it be caused by accumulated dirt over long usage without intermittent cleaning?

As for the IQ degradation using the filter, this is also the first time I'm learning about it. You may very well be right, but then I've heard many testimonial to the contrary on this forum. I just ordered a Hoya Pro-1 CPL based on such testimony, so I'm now anxious to find it all out first-hand!! If you're right, then I just spent the most expensive "lens protector"!!

SYS wrote in post #2569423
Hmmmm... that's the first time I heard of the filter being stuck on the lens. I wonder if the same thing could happen on Canon 10-22.... Could it be caused by accumulated dirt over long usage without intermittent cleaning?

As for the IQ degradation using the filter, this is also the first time I'm learning about it. You may very well be right, but then I've heard many testimonial to the contrary on this forum. I just ordered a Hoya Pro-1 CPL based on such testimony, so I'm now anxious to find it all out first-hand!! If you're right, then I just spent the most expensive "lens protector"!!

Yes, as you can see from the pictures above, there is a small drop in quality, but it's hardly anything that you can't fix with rudimentary sharpening. Really, in all respects it should be a non-issue. Even with all three filters stacked, the image quality is still good and can get better with sharpening.

I think one of the reasons it got stuck on my 10-20mm is because of the Sigma's EX outer finish, which is kind of a non-smooth coating that isn't slippery, so it held onto the filter. Also, the part of the filter that you have to grab to unscrew the filter does not have the best traction for your fingers, and my fingers slipped many times trying to get the filter off.

fuzzybabybunny wrote in post #2568878
Here it is! look at the crops and come to your own conclusions. This is intended as an image quality test on these particular filters.

Canon 30D, Canon 50mm f/1.4, ISO100, f/5.6, autofocused the "BG-E3" for the first shot, then locked into manual focus for all other shots. Straight out of the camera, remote shutter with mirror lockup.

77mm Hoya Pro1 Circular Polarizer, Hoya Pro1 UV, Hoya 8X Neutral Density

You seem so have some loss with even just the UV filter, which is not my experience with the three lenses I have tested with.

There may be a systematic error with your method as you did not AF after fitting the filter and the focus point may have changed slightly.

When I did these tests, to get around the shot to shot variation in AF sharpness I did 10 shots with and 10 shots without the filter using a new AF instance each time and measured the statistical variation in the 50% MTF resolution. There was No significant difference in performance with or without the UV filter (Hoya S-HMC pro1 also).

I tested with 10-22 @ 10mm 200/2.8L and 300/f4L IS.
http://www.zen20934.ze​n.co.uk …Tests/Filter_AF​/index.htm

The flaws in your methodology that I can see are the assumption that the extra glass won't affect the focus and that you didn't affect the focus setting when attaching the different filters. Changes in the refractive index do affect focus without necessarily affecting IQ. As an extreme example, consider underwater photography. Either choose a large target at an appreciable distance or re-focus each time. And it doesn't take a lot of motion to shift focus while you're attaching filters. I commend your effort; these are just a couple of variables you omitted to (document that you) account for in the test.

Hi fuzzybabybunny,

I thought I would just check this particular lens myself. I used the same statistical method for the centre and corner sharpness at f1.4 and f5.6.

Again I can find no significant variation in performance with and without the filter (Hoya SHMC Pro1 UV), although the AF actions do have some spread.

http://www.zen20934.ze​n.co.uk …Tests/Filter_AF​/index.htm

Full marks to you for trying. As Jon noted the filter being glass is likely to change the required focus slightly.

Also the 50/1.4 is focussed by overall linear extension (meaning the lens elements are moved away from the sensor to focus closer). This means it would be very easy to move the focus when attaching and removing the filter.

These two things are probably what tripped your test up.

Hope you feel you can use your filters with more confidence now.

fuzzybabybunny wrote in post #2569365
Oh, I'm completely sure that it will be able to make the sky pop without vignetting. But you're going to be paying a small price with the drop in image quality.

BTW, I would not recommend this filter just for the fact that it is impossible to get off the lens once it's on. I put this on my Sigma 10-20mm and I DID NOT tighten it at all. After a few minutes of just playing around with the rotating ring I went to go take it off and couldn't. I spent a good ten minutes fiddling desperately with it and it finally came off. I cannot risk a filter getting impossibly stuck in the field. It would be very aggravating if it got stuck on my 10-20mm and I needed to put it on my 30mm or something.

This is EXACTLY the reason why B+W filters, which are brass rings rather than aluminum rings, are what I recommend for CPL, where the rotating portion makes it more challenging to remove! This issue is the 'binding' of similar materials vs. the 'lubrication' of dissimilar materials. Newer lenses are often not aluminum, but some engineered plastic, so this issue is probably encountered to a much lesser degree today than 20 years ago.

fuzzybabybunny wrote in post #2569365
BTW, I would not recommend this filter just for the fact that it is impossible to get off the lens once it's on. I put this on my Sigma 10-20mm and I DID NOT tighten it at all. After a few minutes of just playing around with the rotating ring I went to go take it off and couldn't. I spent a good ten minutes fiddling desperately with it and it finally came off. I cannot risk a filter getting impossibly stuck in the field. It would be very aggravating if it got stuck on my 10-20mm and I needed to put it on my 30mm or something.

I understand B+W claim the brass they use solves this issue. I have never quite understood why they say that, as having two dissimilar metals in contact is not generally a good idea from the corrosion perspective. I am sure there is logic.

A good trick with a stuck filter is to just put a rubber band around it. You will find the increased grip will get the thing off very easily.

I must say I have never had a single Hoya UV filter on a lens get stuck in over 25 years. It may only be an issue with low profile polarizers where there is very little edge to get a grip.