dispensing with uv,1a filters....on Canon l series lenses

[Bill Brooks]

I use UV filters, but only as a screw on lens cap. Regular lens caps can pop off in the camera case and grind the front element. The filters are covered with tape so I will not forget, and shoot through them.

 

Using the difference function in photoshop I can see a slight sharpness degradation on all of my Zeiss prime lenses and Cannon 70-200 F4 L lens at 200MM. This is sharpness only, and not a test for flare which I deal with below

 

I saw no sharpness degradation on other Canon L wide angle zooms with a filter because I think they were already soft enough that it did not become a factor.

 

If you have a very bright 255 type straight line beside a 0 black background you can sometimes see an offset ghost image caused by the filter. It is not flare as we think of it, but a subtle second ghost image offset from the main image. It sometimes looks like over sharpening, but it is not, as it is too far offset. Forum regular John Mitchell once asked a question about this effect.

 

I have dropped three lenses without a UV filter, in one case it made no difference, second case the lens had to be repaired, the third case the lens had to be discarded. In every case the front element was in pristine condition after dropping.

 

The ideal bad weather kit for me would be a 24-105 Canon L lens on my 5Ds with a UV filter attached. The UV filter to make the lens more water/sand resistant. The Zoom lens so I do not have to risk internal camera damage by changing lenses. The UV filter will not be a quality factor on this lens used under these conditions. See the forum discussion on weather photographs, started by Colin, for the wonderful use of a UV filter.

 

 

 

I like to shoot in cross lighting or into the sun, so flare created with a filter attached is a big problem for me. I also do not want to pause while unscrewing the filter in some flare prone instances, so I go without.

 

Images shot in flare prone situations like this, that were shot without a filter. Note the shadows.
 

 

 

 

 

 

[John Mitchell]

"It is not flare as we think of it, but a subtle second ghost image offset from the main image. It sometimes looks like over sharpening, but it is not, as it is too far offset. Forum regular John Mitchell once asked a question about this effect."

 

It's Halloween, so I recall asking that question about the "ghost image".  The subject was strongly side-lit as well. I now try to remember to remove my UV filters in those types of lighting situations. Removing the UV filter with long zooms at maximum focal length sounds like a good idea as well. I'll try some tests with that.

[spacecadet]

1 hour ago, dustydingo said:

 

Edo,  I totally agree, that is exactly what I meant when I said "proper handling of camera hanging from shoulder".

 

The number of folk I see carrying their camera with the lens pointing _away_ from their body (and therefore swinging horizontally as they turn their body even slightly) honestly amazes me . . . in fact, I see this more often than I see folk with their lens hood on backwards! Talk about asking for trouble . . . 

 

DD

I put the strap over the right shoulder and under the left arm. It stays put pretty well. Good on a bicycle too.

[Ed Rooney]

32 minutes ago, spacecadet said:

I put the strap over the right shoulder and under the left arm. It stays put pretty well. Good on a bicycle too.

 

I carry my new small cushioned bag with the Sony RX100-6 and a6000 with 10-18 zoom that way. Both cameras have wrist straps and I don't handle them without the wrist strap in place. 

 

I used to do what Bill described, tape budget screw-in filters in place of clip-in caps. Many Nikon filters were 52mm I think. So you could stake up the ones to shoot through. Some of the older Nikon lens hood were clip-ons too. Not good. 

 

My cameras don't get hard use anymore. Jay Maisel used to say, "Why would anyone put a ten-dollar piece of glass in front of a $200 piece of glass." Things were a lot cheaper when he said that. 

[MDM]

2 hours ago, Bill Brooks said:

 

Using the difference function in photoshop I can see a slight sharpness degradation on all of my Zeiss prime lenses and Cannon 70-200 F4 L lens at 200MM. This is sharpness only, and not a test for flare which I deal with below

 

I saw no sharpness degradation on other Canon L wide angle zooms with a filter because I think they were already soft enough that it did not become a factor.

 

 

 

 

Bill - do you have the test files and am explanation of the methodolgy you used to arrive at these conclusions. It would be really interesting to see them if you would care to upload them to Dropbox or the like. 

[MDM]

1 hour ago, Ed Rooney said:

 

 

My cameras don't get hard use anymore. Jay Maisel used to say, "Why would anyone put a ten-dollar piece of glass in front of a $200 piece of glass." Things were a lot cheaper when he said that. 

 

I daresay that good quality filters are a lot better than they used to be when Jay Maisel said that Edo - multicoated glass,  thin and very light. I would guess anywhere between 5% and 10% of the value of the lens is about right. I factor it in when I buy a new lens.

[Ed Rooney]

I agree, Michael. I was quoting Jay but I don't really agree with that thought.

 

I'll quote myself, "Everything's a judgement call." 

 

Edited October 31, 2019 by Ed Rooney

[MDM]

26 minutes ago, Ed Rooney said:

I agree, Michael. I was quoting Jay but I don't really agree with that thought.

 

I'll quote myself, "Everything's a judgement call." 

 

 

Sure thing Edo. I like to learn from my mistakes and one of the biggest mistakes I ever made was with my very first proper camera - a secondhand Minolta SRT with a beautiful standard Rokkor lens. I had no idea the damage I was doing when I tried to clean it by blowing on it and rubbing it with a tissue that must have had some sand on it. I scratched the lens - I can still feel the pain I felt at the time. I also got a few grains of sand inside the camera and the first negatives I ever developed had tracks all along. It taught me to be really fussy with cleaning lenses and to keep my kit as clean as possible as well. I am still very fussy with my kit.😀

[Bill Brooks]

3 hours ago, MDM said:

 

Bill - do you have the test files and am explanation of the methodolgy you used to arrive at these conclusions. It would be really interesting to see them if you would care to upload them to Dropbox or the like. 

 

Test files are long gone, but the methodology is as follows

 

Brick wall shot with filter. Second brick wall shot with no filter. The no filter shot should be refocussed as the filter could change the focus point slightly. Best if you are a long way away from the wall.

 

Load the two shots as two layers in a single file in Photoshop.

 

Align the layers in photoshop to take care of any possible camera movement and slight change in magnification when you refocussed.

 

Change the layer blend mode to "difference" on the top layer.

 

If there is no difference between the two shots the image should be entirely dead black. Where there is a slight difference in one area of the image then that particular area of difference will be slightly lighter. Maybe a value of 10 instead of black 0. I noticed higher values near the edges of the image.

 

You have a flat piece of filter glass in front of the lens. This means a light ray coming in from the side transverses more filter glass thickness than a ray coming straight in. Particularly in a wide angle lens. The front element of the lens has a slight curvature to compensate. The filter does not. So maybe this can be a problem. Maybe not. Speculating.

 

Calibrated monitor, dark room, let eyes adjust. Measure with your info panel and the curser at a big sample setting to allow for changes due to different noise in each layer.

 

I have also used this method to judge the amount of JPG compression changes for different jpg settings on the same image.

[MDM]

1 hour ago, Bill Brooks said:

 

Test files are long gone, but the methodology is as follows

 

Brick wall shot with filter. Second brick wall shot with no filter. The no filter shot should be refocussed as the filter could change the focus point slightly. Best if you are a long way away from the wall.

 

Load the two shots as two layers in a single file in Photoshop.

 

Align the layers in photoshop to take care of any possible camera movement and slight change in magnification when you refocussed.

 

Change the layer blend mode to "difference" on the top layer.

 

If there is no difference between the two shots the image should be entirely dead black. Where there is a slight difference in one area of the image then that particular area of difference will be slightly lighter. Maybe a value of 10 instead of black 0. I noticed higher values near the edges of the image.

 

You have a flat piece of filter glass in front of the lens. This means a light ray coming in from the side transverses more filter glass thickness than a ray coming straight in. Particularly in a wide angle lens. The front element of the lens has a slight curvature to compensate. The filter does not. So maybe this can be a problem. Maybe not. Speculating.

 

Calibrated monitor, dark room, let eyes adjust. Measure with your info panel and the curser at a big sample setting to allow for changes due to different noise in each layer.

 

I have also used this method to judge the amount of JPG compression changes for different jpg settings on the same image.

 

Thanks for posting that Bill. I do intend to have another look at this myself. When I have done tests in the past I can see no visible difference between UV filter and no filter and that is what I tend to base how I work (visible differences). The guy in the second video could see no visible differences but there was a small difference in the file sizes of jpeg images which he was interpreting as more detail in the ones with no filter and hence sharper. 

[sparks]

To everyone that has contributed to this thread....THANK YOU...have sat and read through everything...much appreciated.

 

Best regards

 

SPARKS!

[Klinger]

Since some think this is only about pinpoint sharpness, I'll answer, my opinion, the filter doesn't hurt the sharpness. If you are look at 100% and try to find flaws, there might be something. I'd ask myself, how much does it actually effect a large image, in normal viewing?

 

Depending on the environment you work in and what might get thrown at you, dust, dirt, rocks, water, Etc.

another lens saved, I think it was the 70-200 IS/USM f/2.8

 

If you never have a tripod fall over or light tip or anything ever come near your lens, including a cleaning cloth. Don't bother. If you do use filters, which I do, buy good ones, not some cheap junk. I don't know why someone would scrimp and use a crummy filter, which might make images worse, on an expensive lens. 😉

 

 

Last of all, besides being able to wipe the front of my lens with my shirt or anything else, without worry, when I'm in a rust. And the fact that the filter protects the from element from tiny little as well as big bad things

 

That's why the big L lenses have no giant filter ring, besides obvious costs, and degradation. They already have a clear glass front element.

 

I wonder if the pixel peepers have considered removing these for sharper images? 😀

 

 

Edited November 1, 2019 by Klinger

[MDM]

54 minutes ago, Klinger said:

Since some think this is only about pinpoint sharpness, I'll answer, my opinion, the filter doesn't hurt the sharpness. If you are look at 100% and try to find flaws, there might be something. I'd ask myself, how much does it actually effect a large image, in normal viewing?

 

Depending on the environment you work in and what might get thrown at you, dust, dirt, rocks, water, Etc.

 

another lens saved, I think it was the 70-200 IS/USM f/2.8

 

If you never have a tripod fall over or light tip or anything ever come near your lens, including a cleaning cloth. Don't bother. If you do use filters, which I do, buy good ones, not some cheap junk. I don't know why someone would scrimp and use a crummy filter, which might make images worse, on an expensive lens. 😉

 

 

 

Last of all, besides being able to wipe the front of my lens with my shirt or anything else, without worry, when I'm in a rust. And the fact that the filter protects the from element from tiny little as well as big bad things

 

 

That's why the big L lenses have no giant filter ring, besides obvious costs, and degradation. They already have a clear glass front element.

 

I wonder if the pixel peepers have considered removing these for sharper images? 😀

 

 

 

Totally agree with this and great illustrations. 

[Klinger]

Just now, MDM said:

 

Totally agree with this and great illustrations. 

 

Seems I've seen this question before? 😀 In the end, it's just my opinion, everyone decides on their own.

 

None of these guys have UV filters. LOL

 

[Bill Brooks]

Here is a pixel peepers site that deals with UV filters on lenses.

https://diglloyd.com/articles/Filters/neutrality.html

One thing that he brings up is that UV filters can have slightly different colours on page 4. Also be sure to read page 3 where he deals with sharpness.

I once had a 15 year old B&W polarizor go warm over time. It started out neutral but warmed up over the 15 years. My other B&W polarizors were still neutral. So I had one lens warmer than the others. I took it to the Canadian distributor more as a curousity than anything. After all it was 15 years old. They saw the change and gave me a new one on the spot!

It might be a good idea to look at all of your UV filters together on top of a light balance light box or a white background on a light balance monitor. If there are differences in colour temperature between filters it will be obvious.

You want all of your lenses to create the same colour temperature.

I agree with MDM the most important filter problem is flare.

[John Mitchell]

Interesting take on pixel-peeping here.

 

There's hope...

[MDM]

1 hour ago, Bill Brooks said:

Here is a pixel peepers site that deals with UV filters on lenses.

https://diglloyd.com/articles/Filters/neutrality.html

 

 

 

Thanks again Bill. I'll check that out when I get a bit of time as well as doing some testing myself hopefully soon.

 

 

 

7 minutes ago, John Mitchell said:

Interesting take on pixel-peeping here.

 

There's hope...

 

Yeah tell him to tell that to Alamy QC or to a client - hey man I'm not worried about quality, it's all about the emotion. Getting no more work would be really funny 🤣

[John Mitchell]

7 minutes ago, MDM said:

 

Yeah tell him to tell that to Alamy QC or to a client - hey man I'm not worried about quality, it's all about the emotion. Getting no more work would be really funny 🤣

 

For sure. Stock photography is a different ball game -- i.e. technical quality is obviously very important. However, pixel-peeking can get a bit obsessive these days, thanks to all the remarkable digital technology that we have. Back to UV filters...

[MDM]

33 minutes ago, John Mitchell said:

 

For sure. Stock photography is a different ball game -- i.e. technical quality is obviously very important. However, pixel-peeking can get a bit obsessive these days, thanks to all the remarkable digital technology that we have. Back to UV filters...

Actually pixel-peeking is very relevant to this topic as I think it would take some serious peeking to determine if there is any visible difference between high quality filter and.no filter in most cases. If it is defined as viewing at 100%, then I would not regard it as obsessive at all but an essential part of determining whether an image is suitable for submission for stock, to a client rather simply for printing. 

[John Mitchell]

25 minutes ago, MDM said:

Actually pixel-peeking is very relevant to this topic as I think it would take some serious peeking to determine if there is any visible difference between high quality filter and.no filter in most cases. If it is defined as viewing at 100%, then I would not regard it as obsessive at all but an essential part of determining whether an image is suitable for submission for stock, to a client rather simply for printing. 

 

True, but I have a feeling that most stock photo clients are more concerned with content than absolute sharpness at 100%.

 

I figure that if an image passes Alamy's technical QC -- UV filter or no UV filter attached to the lens -- then chances are it's suitable for customers.

 

Hadn't thought about colour balance, though. I thought UV filters would be pretty much the same in that department. Interesting. I used to use skylight filters for protection back in film days. They certainly varied considerably. I continued to use them for awhile with the first DSLR that I bought and quite liked the slight warming effect. But then I'm a sucker for warm tones.

Edited November 2, 2019 by John Mitchell

[MDM]

30 minutes ago, John Mitchell said:

 

True, but I have a feeling that most stock photo clients are more concerned with content than absolute sharpness at 100%.

 

I figure that if an image passes Alamy's technical QC -- UV filter or no UV filter attached to the lens -- then chances are it's suitable for customers.

 

Hadn't thought about colour balance, though. I thought UV filters would be pretty much the same in that department. Interesting. I used to use skylight filters for protection back in film days. They certainly varied considerably. I continued to use them for awhile with the first DSLR that I bought and quite liked the slight warming effect. But then I'm a sucker for warm tones.

 

Sure - content trumps all. The sharpness check is a simple way of trying to ensure some base level of technical quality although no doubt masses of technically questionable stuff must get through the QC border. Checking images at 100% is essential anyway if one is going to sell images anywhere so I think that this is a positive thing. 

 

I wouldn't be too worried about colour casts from high quality filters as there is probably as much variation between lenses and way more in how white balance is determined by different cameras,  easily corrected in post in any case if shooting raw. A bigger difference would be what we are all seeing on screen anyway. The bottom line for me is I won't be dumping my UV filters.

[John Mitchell]

2 hours ago, MDM said:

 

Sure - content trumps all. The sharpness check is a simple way of trying to ensure some base level of technical quality although no doubt masses of technically questionable stuff must get through the QC border. Checking images at 100% is essential anyway if one is going to sell images anywhere so I think that this is a positive thing. 

 

I wouldn't be too worried about colour casts from high quality filters as there is probably as much variation between lenses and way more in how white balance is determined by different cameras,  easily corrected in post in any case if shooting raw. A bigger difference would be what we are all seeing on screen anyway. The bottom line for me is I won't be dumping my UV filters.

 

That's a good point about lenses. I find that each of my Sony lenses has a slightly different colour balance. The zooms seem warmer than the primes for some reason. I have a couple of old MF Minolta prime lenses that I use occasionally, and images captured with them have a "richer" look than modern lenses -- i.e. the colours appear to have more depth to my eye. I too will be keeping my UV filters on most of the time. To UV or not to UV is one of those arguments that will probably go on forever.

[Klinger]

I read the links, interesting. I'm not on a mission and I only own one full frame camera, a 1DsII that I got used. Nice. Most of the time it sits at home in a bag, I like my crop cameras better. But, I'm going way off...

 

If someone uses AWB then the filter does nothing to the color. Something to  put  in the back of your mind. I have used a 25B (if I remember right)? Anyways, as a window on an outdoor box. The filter was a buck from one of those bins you might find at a camera store. My "camera in a box" project I wanted at least some nice glass in front of the camera lens? So I bought the biggest one in the box, 85mm, it's some kind of dark red.

 

 

Lilly and tulip timelapse, photo bombed by a bunny.

 

The photos were shot with a 20-D and they look just like daylight, because AWB adjusts. Isn't digital wonderful? Except when I want a nice Sunset that's got all kinds of subtle pastel colors, which I have to recreate in edit. 😖

 

Not sure if this is true with a grey card? Anyone?

 

Now if someone uses manual settings, then true, filters are not all the same.

 

[Allan Bell]

 

Dispense with the UV filters and buy the totally clear digital protection filters if you still need something to protect the front element.

 

Problem solved.

 

Allan

 

[MDM]

2 hours ago, Klinger said:

I read the links, interesting. I'm not on a mission and I only own one full frame camera, a 1DsII that I got used. Nice. Most of the time it sits at home in a bag, I like my crop cameras better. But, I'm going way off...

 

If someone uses AWB then the filter does nothing to the color. Something to  put  in the back of your mind. I have used a 25B (if I remember right)? Anyways, as a window on an outdoor box. The filter was a buck from one of those bins you might find at a camera store. My "camera in a box" project I wanted at least some nice glass in front of the camera lens? So I bought the biggest one in the box, 85mm, it's some kind of dark red.

 

 

Lilly and tulip timelapse, photo bombed by a bunny.

 

The photos were shot with a 20-D and they look just like daylight, because AWB adjusts. Isn't digital wonderful? Except when I want a nice Sunset that's got all kinds of subtle pastel colors, which I have to recreate in edit. 😖

 

Not sure if this is true with a grey card? Anyone?

 

Now if someone uses manual settings, then true, filters are not all the same.

 

AWB isn't always accurate and there is a lot of variation between cameras as well. A lot of Nikon cameras are set to give an AWB on the cool side which tends to render better skin tones. There is an alternative warmer AWB setting as well. AWB will also be influenced by the colour of the light and the surroundings. It can be a bit of a mystery. I don't worry about it as I always adjust in post anyway and it is often a matter of taste as well as the fact that different (calibrated even) screens can give different results.

 

Using a grey card at sunset will tend to bring the colour back towards a cool rendering. I wouldn't use a grey card if I wanted to capture the warm sunset colours. Your shot of the tulips there looks a bit cool to me in fact (a little too blue I would guess). If you used a grey card and modified accordingly in post, I would guess it would go warmer. So much of this is subjective as the eye adapts to anything it seems.

 

47 minutes ago, Allan Bell said:

 

Dispense with the UV filters and buy the totally clear digital protection filters if you still need something to protect the front element.

 

Problem solved.

 

Allan

 

 

What problem Allan? I don't see any problem and I don't think I will be binning my UV filters any time soon. 

Edited November 3, 2019 by MDM