topic Re: What the heck's going on here? in EOS DSLR & Mirrorless Cameras

What the heck's going on here?

CapeCodDan — Sat, 25 May 2019 12:11:17 GMT

Hi all, I'm perplexed by a couple of recent images I've taken with my 6DMII; hoping you'll take a look and offer any thoughts as to what's going on and whether the issues are related. I've reached out to CPS and they've not been able to offer any constructive advice. Both images downsized for upload. (1) The group shot was taken with my 17-40 f/4L at 29mm, UV filter, ISO 200, f7.1, 1/125, on a monopod. Peripheral Illumination, Chromatic Aberration, and Diffraction corrections ON. Note the people on the left and right sides are soft, and I may be seeing some CA, esp on the right. (2) The shoreline pic (using my 70-200 f/2.8L USM at 165mm, CPL filter, ISO 500, f8, 1/640). One-shot AF, Zone AF. Peripheral Illumination, Chromatic Aberration, and Diffraction corrections ON. While the foreground bushes are supposed to be out of focus, and the man (on which I focused) is fine, everything degrades horribly - even the right side of the house is fine but the left is terrible. (a) could this one be the fault of the polarizing filter? (b) are these issues camera-related or lens-related? I see no such issues with any lens on my crop-sensor 80D and 70D. I would expect some issues on a full frame sensor in the corners, but these problems are not in the corners. Help!

Re: What the heck's going on here?

Waddizzle — Sat, 25 May 2019 12:30:01 GMT

I do not see anything that jumps out as wrong. I only use B+W clear filters. I also shoot RAW with all of those settings turned off.

I would have used a much faster shutter for the group photo. Your camera already has a UV filter built into the sensor assembly. No need for it.

The landscape shot is fine. I have found CPL filters can have a negative impact on the phase detection AF system. I rarely use one, anymore. When I do, I am using a tripod and focusing manually.

Re: What the heck's going on here?

Ray-uk — Sat, 25 May 2019 14:33:20 GMT

I can't see anything wrong with the group pic but it's difficult to tell as it has been downsized.

The other shot however is really wierd, it looks like you've used some cheapie lens from the 1950s, I would certainly try again without the filter.

Re: What the heck's going on here?

wq9nsc — Sat, 25 May 2019 14:51:09 GMT

What you are talking about is far more obvious in the second image although the "softness" in the first image (which I think is actually from the out of focus away from center issue) is visible.

I have owned a 17-40 F4 for years and used it for a variety of shots and have never seen anything like the results you posted. Ray-UK describes it very well as looking like what you would get from a cheap lens from the early days.

Google the seven deadly sins lens rental blog and the first result should be a website that clearly and accurately describes the sorts of astigmatism and curvature that can occur in lenses but are normally accounted for during the design of quality lens like your 17-40 L series Canon. If the filter on front isn't causing the issue then it sounds like a problem has developed with your lens and perhaps one of the movable elements is no longer tracking with its mates as it should.

Try shooting a couple of similar scenes with the lens wide open (F4) and see if this effect becomes more noticeable which it normally would from typical lens aberrations.

And on edit: I didn't realize when I first read this that the second image was shot with a different lens. Very odd and the filter is the most likely problem. It will be interesting to see how this turns out.

Rodger

Re: What the heck's going on here?

shadowsports — Sat, 25 May 2019 15:33:50 GMT

Group shot - Wasn't a particularly sunny day. That one's tough. I see the softness near the edges (both sides). I agree with Wadizzle about shutter speed. 1/125 is just barely enough to freeze people's movement who are standing close to one another and fidgeting.

Very slight CA present, most noticable on verticle edge of dresses where light and dark meets. Focus would be a challenge. You have subjects which are 4 deep and concave. F11 might have helped given your DOF challenges with the photo.

I would have tried taking 9 shots, 3 each with different ISO, Shutter and Aperature. I believe I have Peripheral Illumination, Chromatic Aberration, and Diffraction corrections ON normally. Always easy to look back and see what you might have tried or done better.

What Wq9nsc points out about lens refraction or the lens being out of calibration is also possible. Might be a good idea to have it checked.

Agree with the guys about the home shot.

Re: What the heck's going on here?

ebiggs1 — Sat, 25 May 2019 17:00:36 GMT

Top one of the group is a tough shot. I do that type work all the time and for way more years than I like to think.

WA and UWA lenses act like that. Its just the way it is. You need to not frame so tight. Make sure what you want, the subject, has some room around it. Later crop to the required size. I hate to admit it but the 17-40mm and even the newer 16-35mm, 1 and 2, are guilty. Not my first choices. I have had multiple copies of the the 17-40mm and first version 16-35mm. I am not in the market for the second! Frame large and crop.

Did you mention whether you used Raw file format? If you don't you should. You can forget most all camera settings except focus and exposure. The other settings can be and should be done in post editing. If you do work like the top photo you should already be a LR and/or PS user.

Re: What the heck's going on here?

CapeCodDan — Mon, 27 May 2019 13:09:50 GMT

Thanks all, I'm going to experiment with the landscape (seashore) pic, which had a polarizer on the front of the 70-200...shoot one with and one without. On that one I'm guessing the filter's the problem. With the group, in retrospect I could have used my 24-70 since I shot it at 29mm....and/or moved the ladder back. Seems like such a waste of pixels to have to shoot too wide then crop to the center...I could achieve the same end, I suppose, by using the 80D body. Frustrating because my gear doesn't typically let me down like this!

Re: What the heck's going on here?

ebiggs1 — Mon, 27 May 2019 14:05:13 GMT

The choice of lens, or gear, for the subject should always be a priority. The 16-35mm type UWAs are good for things like landscapes, etc, but not so good for people. The more intimately recognizable, a person's face for instance, the more faithful reproduction is required.

In the case of most UWA lens that means staying closer to the center.

Re: What the heck's going on here?

TTMartin — Mon, 27 May 2019 16:06:17 GMT

@CapeCodDan wrote:
Thanks all, I'm going to experiment with the landscape (seashore) pic, which had a polarizer on the front of the 70-200...shoot one with and one without. On that one I'm guessing the filter's the problem. With the group, in retrospect I could have used my 24-70 since I shot it at 29mm....and/or moved the ladder back. Seems like such a waste of pixels to have to shoot too wide then crop to the center...I could achieve the same end, I suppose, by using the 80D body. Frustrating because my gear doesn't typically let me down like this!

I would suspect the filters are the issue here. The only other possibility is that your sensor was exposed to extremes in temperature and humidity and is dirty. The easiest thing to test is ditching the filters.

Re: What the heck's going on here?

ebiggs1 — Tue, 28 May 2019 13:33:28 GMT

Another problem when using a UWA lens is you must keep it perpendicular and square and centered to the subject. You did neither if you look at the risers you can see you were off a bit. You will always have geometry distortion. A tripod with level is a possible solution.

Re: What the heck's going on here?

RobertTheFat — Tue, 28 May 2019 13:52:07 GMT

@ebiggs1 wrote:
Another problem when using a UWA lens is you must keep it perpendicular and square and centered to the subject. You did neither if you look at the risers you can see you were off a bit. You will always have geometry distortion. A tripod with level is a possible solution.

I've found the full-time level on the 5D4 to be a great help in this respect. I wish my 5D3 and 7D's had it.

Re: What the heck's going on here?

TTMartin — Wed, 29 May 2019 13:46:42 GMT

@RobertTheFat wrote:
@ebiggs1 wrote:
Another problem when using a UWA lens is you must keep it perpendicular and square and centered to the subject. You did neither if you look at the risers you can see you were off a bit. You will always have geometry distortion. A tripod with level is a possible solution.
I've found the full-time level on the 5D4 to be a great help in this respect. I wish my 5D3 and 7D's had it.

The 7D Mk II has it.

Re: What the heck's going on here?

RobertTheFat — Wed, 29 May 2019 20:49:17 GMT

@TTMartin wrote:
@RobertTheFat wrote:
@ebiggs1 wrote:
Another problem when using a UWA lens is you must keep it perpendicular and square and centered to the subject. You did neither if you look at the risers you can see you were off a bit. You will always have geometry distortion. A tripod with level is a possible solution.
I've found the full-time level on the 5D4 to be a great help in this respect. I wish my 5D3 and 7D's had it.
The 7D Mk II has it.

The 7D2 does have an electronic level, but it displays only on the LCD screen, not in the viewfinder as the 5D4's level does. The 5D4's level is much more useful, IMO.

IIRC, the 5D3 does have a way to use the AF point display as a level, but it's much clumsier and less accurate than the 5D4's level. There may be a way to get the 7D2 to behave similarly. (The controls on the 5D3 and on the 7D2 are nearly identical.) But I spent a half hour with my wife's 7D2 this afternoon and wasn't able to find it.

Re: What the heck's going on here?

Waddizzle — Fri, 31 May 2019 12:08:30 GMT

The 7D2 has level display in the viewfinder. It is found in the [SET UP2 : Viewfinder Display] menu. This is the yellow wrench menus.

Re: What the heck's going on here?

RobertTheFat — Fri, 31 May 2019 12:44:12 GMT

@Waddizzle wrote:
The 7D2 has level display in the viewfinder. It is found in the [SET UP2 : Viewfinder Display] menu. This is the yellow wrench menus.

Yes! Thanks, Waddizzle! I had managed to discover how to turn the level on and off on the 5D4, but didn't think to look back at the 7D2 to see if it worked the same way. Even though Tom had alerted me that the level is there, I still had it in my head that the 7D2 is merely a diminutive 5D3. Live a lot, learn a little, I guess.

Re: What the heck's going on here?

ebiggs1 — Fri, 31 May 2019 15:32:58 GMT

"I had managed to discover how to turn the level on and off on the 5D4,..."

The 1DX has this feature, too. When I was younger I never had need of a level. I never had out of square or out of level shots. But as I age it seems like the level is a nice feature.

Re: What the heck's going on here?

Waddizzle — Sat, 01 Jun 2019 12:06:50 GMT

@RobertTheFat wrote:
@Waddizzle wrote:
The 7D2 has level display in the viewfinder. It is found in the [SET UP2 : Viewfinder Display] menu. This is the yellow wrench menus.
Yes! Thanks, Waddizzle! I had managed to discover how to turn the level on and off on the 5D4, but didn't think to look back at the 7D2 to see if it worked the same way. Even though Tom had alerted me that the level is there, I still had it in my head that the 7D2 is merely a diminutive 5D3. Live a lot, learn a little, I guess.

Here is neat shortcut to navigate the Canon menus. Press the [Menu} button to open up menus. Now press [Q] a few times.

Re: What the heck's going on here?

Waddizzle — Sat, 01 Jun 2019 12:27:02 GMT

@ebiggs1 wrote:
Another problem when using a UWA lens is you must keep it perpendicular and square and centered to the subject. You did neither if you look at the risers you can see you were off a bit. You will always have geometry distortion. A tripod with level is a possible solution.

What he is saying about keeping the camera level with a UWA lens is true. The 6D2 has a built-in level in the viewfinder, and a tripod for shots that must be absolutely tack sharp is a good idea, too.

I am not seeing the same softness at the edges. I see two ladies on the right standing next to one another. One is soft, while the other is sharp. That is a result of slow shutter.

I grabbed a couple of images from my Facebook page. These two images were taken with a 6D2 and the EF 16-35mm f/2.8L II USM at 16mm and f/8.. I chose these because of the detail at the edges.

The tree along the right side seems sharp, top to bottom, as is the rock wall on the lower left.

The tree on the left side of this image seems sharp, too. The grass seems sharp, as well as the leaves overhead.

Maybe I got lucky and got a good copy. Or, maybe I do not see the softness at the edges, which is entirely possible.

Re: What the heck's going on here?

Waddizzle — Sat, 01 Jun 2019 14:26:53 GMT

Here are two crops of those same images. This is what I am seeing in the corners on my laptop.

I think the images from my EF 16-35mm f/2.8L II USM are fine. Am I wrong?

Re: What the heck's going on here?

CapeCodDan — Mon, 03 Jun 2019 11:46:29 GMT

Great input from everyone. Just to follow up on my original post, I've now learned all about Canon MTF charts and the one for my 17-40 f/4L is truly awful!! See https://www.usa.canon.com/internet/portal/us/home/products/details/lenses/ef/ultra-wide-zoom/ef-17-40mm-f-4l-usm

I'm attaching a better view of my original posted image, comparing left side to center to right side. You can see the problems are not a result of camera or people movement.

The good news is I did another similarly shaped group yesterday; this time used my 24-70 f/2.8L @ 34mm, f/9, 1/250, with terrific results - everyone sharp left to right.