Help judging performance of my FE55z, FE35f2.8z horizon/infinity

Started Jul 5, 2016 | Questions
l_d_allan
l_d_allan Veteran Member • Posts: 5,091
Details how I attempt to get alignment (may or may not be adequate) and other related issues

JimKasson wrote:

l_d_allan wrote:

JimKasson wrote:

l_d_allan wrote:

I think the assumption that near-infinity horizons are acceptable for lens evaluation is an obsolete carry-over of the [bad] old days of film.

IIRC, A.A. relied on testing with trees on the horizon, and what I think he described as "infinite detail the closer you looked".

In terms of cycles per picture height, an 8x10 view camera with film in it is nothing to sneeze at, even by today's standards. Such negatives are sufficiently sharp that there is a clear difference between an 8x10 silver-gelatin contact print on F paper and an identically sized print made in an enlarger.

Not meaning to be argumentative (moi ?), but surely you aren't claiming/extrapolating that what was sufficient for the 8x10" view camera you may still own is therefore fine and dandy for a 42 mpx Super-Exmor?

I sold my Arca Swiss 8x10 about 8 years ago. Actually, I traded it for part of a new Nikon 400/2.8. I still have 'chromes made with that camera. There is nothing in digital photography like putting one of those on a light box. With panos, you can beat the resolution, but you can't print that sharp. I also own 8x10 and 8x20 silver contact prints. They are amazing, too.

Consider this: with 20 cy/mm on an 8x10, you'd get 4000 cy/ph. I did that in my head; I hope I got it right.

Sorry, I was unclear. I don't doubt that the equivalent of a b/w slide from the low ASA film A. Adams used would have stunning details. BTW: Could he make direct 'chromes like you mentioned, or was that later?

I can also believe that 20 cy/mm for some MTF-## was sufficient for A.A.'s large view cameras. He was correct to assert he could check with distant trees at the near-horizon.

However, I have my doubts that a technique that was satisfactory for 20 cy/mm can be extrapolated to our 42 mpx Super-Exmor's. Would we be satisfied with a lens that  LR measured as delivering 20 cy/mm at MTF - [fill-in-the-blank]?

Quick math: is that 480 cy/ph for a 24mm high full frame sensor? Should we be ok with a test that had the limit of 480 cy/ph? Or am yet again "unclear on the concept". Or confused whether lp/ph is more or less equivalent to cy/ph, and  cy/mm is pretty much equivalent to cy/mm?

And I do realize that your climate situation may very well allow you to "get away with" near-horizon tilted captures ... especially since they are right outside your door and thus much handier than a brick wall you'd have to drive to.

I'd suggest that a reasonable guideline for the rest of us might be that:

  • IFF you have a suitable climate (which we both do)
  • IFF you can walk to a suitable scene with near-infinity flatness of field targets (see below for my situation) ... then
  • Knock yourself out with tilted horizons

But remember that it's qualitative.

Don't know what you mean by that .... a target with sufficient detail?

And then there's focus. And field curvature.

I realize those issues apply to brick walls, but do they not also apply to near-infinity horizons? Do you mean something like: "Use near-infinity horizons with a tilt for lens testing, since focus and field curvature aren't nearly as critical and you can be relatively sloppy about them compared to brick walls."

  • Otherwise if you have to drive, consider using a brick wall (of which I have 2+ within walking distance so I don't have to drive to do that testing)

Alignment? How are ya gonna do that? not saying it's impossible, but what's your proposal?

Well, since you asked:

My practice has been that the school with a brick wall I use has a perpendicular line coming out from the brick wall. I can check if I have an image that shows that. Nope ... in the image below, picture a line for the concrete you can see, except coming out 50 feet or so.

With the tripod legs straddling that perpendicular line, I feel I can achieve satisfactory alignment with a tape measure and 18" level on the tripod head.

I did something similar inside when I was using a borrowed LensAlign device for AFMA of Canon equipment with a hallway that had floor tiling. I got add added confidence in the approach since a mirror agreed with my tape-measure derived alignment.

If and when I do non-MtfMapper lens testing again, I'll try to remember to fuss with mirror confirmation of the tape-measure approach I utilized.

I am curious if you feel mirror confirmation would be satisfactory for confidence that alignment was adequate for "good vs bad copy testing".

Again, I'm not claiming that would be adequate to get valid +/- 100 numbers for MtfMapper analysis.

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l_d_allan
l_d_allan Veteran Member • Posts: 5,091
Re: Help judging performance of my FE55z, FE35f2.8z horizon/infinity

JimKasson wrote:

Here's the scoop on the Sony 35mm. ALL of them have a tilt that will manifest itself in a noticeably less detailed right or left side.

How do you know that?

He may be referencing the infamous / notorious LR blog article in which 10 of 10 FE35's were out-of spec. It "earned" being in the category which at the time was described in another article as "crap shot q/c" (from 4.0 to 5.0).
https://www.lensrentals.com/blog/2015/10/sony-e-mount-lens-sharpness-bench-tests/

So a more accurate statement might be "10 of 10 FE35's were rejects".

That doesn't preclude yours (JK) being fine.

IIRC, the FE90 was 4.5, also significantly under a consistency/variance score of 5.0, which also put it in the "crap shot q/c" category. I think you've been more than impressed with your copy, but maybe I'm thinking of someone else, or another lens you own.

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l_d_allan
l_d_allan Veteran Member • Posts: 5,091
Re: Help judging performance of my FE55z, FE35f2.8z horizon/infinity

holin wrote:

Here's an unverified idea for cheap aligment. Aligning to a wall is difficult, even with lasers it takes some work and there are multiple sources of uncertainty. However, floors (and ceilings) are level in modern buildings, usually done with a self leveling compound (think how water surface levels itself). My arca clamp has a bubble level that can be used to point the camera straight up or down, which should make it parallel to a level floor or ceiling. Maybe this would work, at least better than trying to align to a wall, if no specialist setup is available.

Mostly agree.

I've done AFMA indoors several times with a camera club loaned LensAlign, and there are definite advantages to being indoors. The location I used had tiled flooring that came out perpendicular to the wall. That provided a double check on the LensAlign mirror by using a tape measure.

However, lighting can be somewhat more difficult indoors. Building can vibrate more than you might realize from wind, HVAC cycling, nearby traffic (especially trucks), people walking around (even on a different floor),  etc.

The bigger problem I encountered was getting far enough away for longer focal lengths.

With shorter focal lengths, it can be difficult or impossible to get all four corners in the capture (which I understand to be at least partial justification for the "tilted horizon" approach).

My perhaps flawed impression is that the level of "attention to detail" for alignment is about the same for:

  • AFMA with LensAlign 
  • "good copy vs bad copy testing" with a brick wall.
  • ...
  • I found there was a definite learning curve with both.
  • I'm not claiming the "attention to detail" sufficient for brick wall testing is appropriate for the more demanding challenge of getting valid, repeatable +/- 100 numbers for MtfMapper tests.
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JimKasson
JimKasson Forum Pro • Posts: 26,981
How much depth tolerance at infinity focus?
1

Here is a plot of on-axis MTF50, measured in cycles/picture height, for a simulated Otus 55mm f/1.4 (actually, it's a 55mm lens with the aberrations of an Otus 85/1.4), mounted on an a7RII, focused at 10 km, with various object distances:

You can use this chart to find safe distances for distant objects in the field of your lens testing, assuming that the lens that you're testing isn't better than the Otus. If you do have lenses that are better than the Otus, let me know; I can re-run the curves for a diffraction-limited lens.

Here's how to use the chart. Pick the aperture you're going to use, and find the curve o for that aperture. Start at the left hand side of the graph, and run your finger along the curve until you find the place where it starts to bend down. For the f/2.8 curve, that's about 500 meters. Your lens testing will be unaffected by object distance as long as objects that you use to judge sharpness are all more distant than 500 meters.

To get the distances for other focal lengths, do the above, and then multiply the distance by:

(f/55)^2

where f is the focal length in mm of the lens that you want to test.

Jim

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JimKasson
JimKasson Forum Pro • Posts: 26,981
Informal infinity test of Zony 35/2.8

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

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Nephi Contributing Member • Posts: 531
Re: Help judging performance of my FE55z, FE35f2.8z horizon/infinity

l_d_allan wrote:

JimKasson wrote:

Here's the scoop on the Sony 35mm. ALL of them have a tilt that will manifest itself in a noticeably less detailed right or left side.

How do you know that?

He may be referencing the infamous / notorious LR blog article in which 10 of 10 FE35's were out-of spec. It "earned" being in the category which at the time was described in another article as "crap shot q/c" (from 4.0 to 5.0).
https://www.lensrentals.com/blog/2015/10/sony-e-mount-lens-sharpness-bench-tests/

So a more accurate statement might be "10 of 10 FE35's were rejects".

That doesn't preclude yours (JK) being fine.

IIRC, the FE90 was 4.5, also significantly under a consistency/variance score of 5.0, which also put it in the "crap shot q/c" category. I think you've been more than impressed with your copy, but maybe I'm thinking of someone else, or another lens you own.

I am not referring to that article. I am specifically talking about the 35mm 2.8 and a conversation I had with Roger C. His words below:

"Unfortunate reality is all we can do is screen to make sure the lenses we have are in normal range for that lens. With Sony's 35s, normal is that there is a tilt and one corner or one side is going to be slightly softer than the others. I've never tested one that wasn't that way. All of ours are slightly tilted. Same with the 35mm f/1.4. We've screened out the bad ones, but the rest are what they are.

My opinion, with both lenses, after disassembling and trying optical adjustment, is that the optomechanical design of the lenses just doesn't allow tilt to be completely corrected. Basically, as sub-supplier who said they could deliver a certain accuracy couldn't and there is no optical adjustment available in the lens to compensate."

My experience mirrors his with multiple copies. However, I don't find the tilt to be minor. I find it to be fairly noticeable on either the right or left.

JimKasson
JimKasson Forum Pro • Posts: 26,981
Re: Help judging performance of my FE55z, FE35f2.8z horizon/infinity

Nephi wrote:

l_d_allan wrote:

JimKasson wrote:

Here's the scoop on the Sony 35mm. ALL of them have a tilt that will manifest itself in a noticeably less detailed right or left side.

How do you know that?

He may be referencing the infamous / notorious LR blog article in which 10 of 10 FE35's were out-of spec. It "earned" being in the category which at the time was described in another article as "crap shot q/c" (from 4.0 to 5.0).
https://www.lensrentals.com/blog/2015/10/sony-e-mount-lens-sharpness-bench-tests/

So a more accurate statement might be "10 of 10 FE35's were rejects".

That doesn't preclude yours (JK) being fine.

IIRC, the FE90 was 4.5, also significantly under a consistency/variance score of 5.0, which also put it in the "crap shot q/c" category. I think you've been more than impressed with your copy, but maybe I'm thinking of someone else, or another lens you own.

I am not referring to that article. I am specifically talking about the 35mm 2.8 and a conversation I had with Roger C. His words below:

"Unfortunate reality is all we can do is screen to make sure the lenses we have are in normal range for that lens. With Sony's 35s, normal is that there is a tilt and one corner or one side is going to be slightly softer than the others. I've never tested one that wasn't that way. All of ours are slightly tilted. Same with the 35mm f/1.4. We've screened out the bad ones, but the rest are what they are.

My opinion, with both lenses, after disassembling and trying optical adjustment, is that the optomechanical design of the lenses just doesn't allow tilt to be completely corrected. Basically, as sub-supplier who said they could deliver a certain accuracy couldn't and there is no optical adjustment available in the lens to compensate."

My experience mirrors his with multiple copies. However, I don't find the tilt to be minor. I find it to be fairly noticeable on either the right or left.

Thanks. Did you see my samples?

Jim

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Nephi Contributing Member • Posts: 531
Re: Informal infinity test of Zony 35/2.8

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim.  I think the left side is definitely soft compared to the right.  Hard to tell from the image though.  I'd bet if you shot buildings or something with hard lines you find the left side stands out.  Based on my experience though that's a decent copy with a "normal" slightly softer side.

JimKasson
JimKasson Forum Pro • Posts: 26,981
Re: Informal infinity test of Zony 35/2.8

Nephi wrote:

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim. I think the left side is definitely soft compared to the right. Hard to tell from the image though. I'd bet if you shot buildings or something with hard lines you find the left side stands out. Based on my experience though that's a decent copy with a "normal" slightly softer side.

Maybe so. maybe I'll do shoot some targets. But this is certainly not something that would affect any photograph that I'd choose that lens to make in any meaningful way. It's not trying to be an Otus 35 (if there were such a thing) or even a Sigma 35.

Jim

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osv Veteran Member • Posts: 9,970
Re: Informal infinity test of Zony 35/2.8

Nephi wrote:

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim. I think the left side is definitely soft compared to the right. Hard to tell from the image though. I'd bet if you shot buildings or something with hard lines you find the left side stands out. Based on my experience though that's a decent copy with a "normal" slightly softer side.

i think that it's worse than slightly soft, but how can anyone tell with such small pics... were they downrezzed, 100% partial crop, or ?? did the raws get touched by sony in-camera corrections? etc.

flip side is that it's a tough test because it's a landscape that was shot wide open... does the left side clean up at any aperture? well, maybe not: "As you stop down there is very little change. The center improves a little to excellent levels but there is next to no improvement outside of the center. So at typical settings for landscape use, e.g. f/8 or f/11 other much cheaper lenses are sharper in the corners. The Canon FD 2.8/35 for example." http://phillipreeve.net/blog/review-carl-zeiss-sonnar-fe-2-835-za-t/

there was a thread on fredmirada(?) where several people were complaining about shooting landscapes with this lens.

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dan

Nephi Contributing Member • Posts: 531
Re: Informal infinity test of Zony 35/2.8

osv wrote:

Nephi wrote:

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim. I think the left side is definitely soft compared to the right. Hard to tell from the image though. I'd bet if you shot buildings or something with hard lines you find the left side stands out. Based on my experience though that's a decent copy with a "normal" slightly softer side.

i think that it's worse than slightly soft, but how can anyone tell with such small pics... were they downrezzed, 100% partial crop, or ?? did the raws get touched by sony in-camera corrections? etc.

flip side is that it's a tough test because it's a landscape that was shot wide open... does the left side clean up at any aperture? well, maybe not: "As you stop down there is very little change. The center improves a little to excellent levels but there is next to no improvement outside of the center. So at typical settings for landscape use, e.g. f/8 or f/11 other much cheaper lenses are sharper in the corners. The Canon FD 2.8/35 for example." http://phillipreeve.net/blog/review-carl-zeiss-sonnar-fe-2-835-za-t/

there was a thread on fredmirada(?) where several people were complaining about shooting landscapes with this lens.

Dan,
The images can be downloaded full rez.  Did you see that option?

I'd love to read the thread on the 35mm and landscapes.  Any chance you can find it again?  What were they complaining about?

JimKasson
JimKasson Forum Pro • Posts: 26,981
User error

osv wrote:

Nephi wrote:

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim. I think the left side is definitely soft compared to the right. Hard to tell from the image though. I'd bet if you shot buildings or something with hard lines you find the left side stands out. Based on my experience though that's a decent copy with a "normal" slightly softer side.

i think that it's worse than slightly soft, but how can anyone tell with such small pics... were they downrezzed, 100% partial crop, or ?? did the raws get touched by sony in-camera corrections? etc.

flip side is that it's a tough test because it's a landscape that was shot wide open... does the left side clean up at any aperture? well, maybe not: "As you stop down there is very little change. The center improves a little to excellent levels but there is next to no improvement outside of the center. So at typical settings for landscape use, e.g. f/8 or f/11 other much cheaper lenses are sharper in the corners. The Canon FD 2.8/35 for example." http://phillipreeve.net/blog/review-carl-zeiss-sonnar-fe-2-835-za-t/

there was a thread on fredmirada(?) where several people were complaining about shooting landscapes with this lens.

Is my face red! The camera was set on APS-C crop, and I never noticed. I'll repeat the test tomorrow.

Jim

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Nephi Contributing Member • Posts: 531
Re: User error

JimKasson wrote:

osv wrote:

Nephi wrote:

JimKasson wrote:

The center is certainly sharper than the corners wide open. The famous vignetting is not a problem at all AFAIC. The corners are all about the same sharpness. If I were splitting hairs, I might ding the left side a tiny bit, but it's nothing that will affect normal photography. Lr CC 2015.6, defaults except for Exposure boost, WB Daylight.

Jim

Thanks for the test Jim. I think the left side is definitely soft compared to the right. Hard to tell from the image though. I'd bet if you shot buildings or something with hard lines you find the left side stands out. Based on my experience though that's a decent copy with a "normal" slightly softer side.

i think that it's worse than slightly soft, but how can anyone tell with such small pics... were they downrezzed, 100% partial crop, or ?? did the raws get touched by sony in-camera corrections? etc.

flip side is that it's a tough test because it's a landscape that was shot wide open... does the left side clean up at any aperture? well, maybe not: "As you stop down there is very little change. The center improves a little to excellent levels but there is next to no improvement outside of the center. So at typical settings for landscape use, e.g. f/8 or f/11 other much cheaper lenses are sharper in the corners. The Canon FD 2.8/35 for example." http://phillipreeve.net/blog/review-carl-zeiss-sonnar-fe-2-835-za-t/

there was a thread on fredmirada(?) where several people were complaining about shooting landscapes with this lens.

Is my face red! The camera was set on APS-C crop, and I never noticed. I'll repeat the test tomorrow.

Jim

How funny.  Maybe I should test in APC-C mode?

When you do a test through in a level shot as well.  The tilt throws my brain off.

osv Veteran Member • Posts: 9,970
Re: User error

JimKasson wrote:

Is my face red! The camera was set on APS-C crop, and I never noticed. I'll repeat the test tomorrow.

lol, i would suggest a stiff drink before examining 'em at 100%... if you can get a shot at f/8 as well it would be helpful... in-camera vignetting correction??

unfortunately i can't find the original thread that talked about it, but in this latest version, it looks like fred is a bit less enthusiastic, http://www.fredmiranda.com/forum/topic/1423912/0

from when he took this stunning death valley pic: http://www.fredmiranda.com/forum/topic/1271855/1

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dan

osv Veteran Member • Posts: 9,970
Re: User error

Nephi wrote:

When you do a test through in a level shot as well. The tilt throws my brain off.

that's the exact same thing i posted out here a couple of months ago, lol

what's interesting about these tilt shots is how the bottom corners compare.

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dan

JimKasson
JimKasson Forum Pro • Posts: 26,981
Full sized images

These are full frame. Sorry for the earlier error. Comments?

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Nephi Contributing Member • Posts: 531
Re: Full sized images

IMO, the left side softness extends further than the right though it hard to tell as foliage can look soft to begin with.

I'm wondering if Sony just made this lens too small.  I don't believe the Sigma or Canon (or others) have a tilt.  If you photography cityscapes, mountains, architecture, etc. having one side soft is a bummer.  Like I said earlier stopping down helps but the softness is still noticeable.

I read the thread on FM and Fred believes there is no real good choice for 35mm FE lenses at the moment.  Regarding landscapes that is...

JimKasson
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Re: Full sized images

Nephi wrote:

IMO, the left side softness extends further than the right though it hard to tell as foliage can look soft to begin with.

I dunno about that last. The difference between the center and all the edges and sides is pretty striking.

I'm wondering if Sony just made this lens too small. I don't believe the Sigma or Canon (or others) have a tilt. If you photography cityscapes, mountains, architecture, etc. having one side soft is a bummer. Like I said earlier stopping down helps but the softness is still noticeable.

I read the thread on FM and Fred believes there is no real good choice for 35mm FE lenses at the moment. Regarding landscapes that is...

For moderately wide landscapes, I use the Leica-R 28/2.8 (not the cult version), the Zeiss 35 ZF.2, or the new Sigma 24 in an F mount. For wider, I like the Zeiss 15 and 21 ZF.2. I also like the Loxia 21 a lot.

http://blog.kasson.com/?p=12743

http://blog.kasson.com/?p=12784

You don't need AF for landscapes, and certainly not for WA landscapes, IMHO.

Jim

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Re: Full sized images

Nephi wrote:

IMO, the left side softness extends further than the right though it hard to tell as foliage can look soft to begin with.

I'm wondering if Sony just made this lens too small.

For me, small is the whole point of the lens. It's plenty sharp enough for people and street work.

I don't believe the Sigma or Canon (or others) have a tilt. If you photography cityscapes, mountains, architecture, etc. having one side soft is a bummer. Like I said earlier stopping down helps but the softness is still noticeable.

I read the thread on FM and Fred believes there is no real good choice for 35mm FE lenses at the moment. Regarding landscapes that is...

Jim

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l_d_allan
l_d_allan Veteran Member • Posts: 5,091
Re: Full sized images

JimKasson wrote:

These are full frame. Sorry for the earlier error. Comments?

Non-IQ comments (as I have negligible experience with using "tilted near-infinity horizons" (TNIH) for "good copy vs bad copy testing" (GCVBCT):

  • Odd that when you click on the image itself, you get use of the Loupe, and can view much closer than when you click on "Original Size". Has DPR always been that way? "Original Size" is not nearly 1:1 pixel peeking, and neither does the Loupe. Any idea what the viewing ratio is with the Loupe with a7Rii captures of 7952 horizontal pixels?
  • Since you don't care whether the sky blows out or not, seems like you could use a longer exposure ... the EXIF shows EC of -1.3 EV. Do recall if you used "A" mode with EC, or "M" exposure with EC ignored?
  • However, "Sunny 16" with ISO 100 would be 1/3200s at f/2.8, so you clearly didn't use "Sunny 16" (if I did the reciprocity correctly). 1/2000s is actually about +0.7 EV, so perhaps the EXIF value of -1.3 EV reflects where the EC dial was?
  • Do you recall if you used UniWB with Zebras to decide on exposure? If so, what Zebra setting ... I use 100+? Was the sky blinking or not? Or did you back off a click or so from the tree leaves blinking?
  • ...
  • I don' t have that lens, so have no basis of comparison on what the center, near edges at the APS-C off-axis, and extreme corners should look like.
  • I also don't enough experience with TNIH to comment on perceived IQ.
  • We apparently differ on whether validly done TNIH captures tends to be better, worse, or about the same as a validly done brick wall IQ test for GCVBCT.
  • How far away would you estimate the tree line is at the horizon? Half mile? Full mile? Less? More? Ever actually stepped it off, if that would be feasible?
  • What magnification of focal length would your estimate work out to be? 1000X or greater? Much greater?
  • It wouldn't surprise me if you have a laser range estimator with at least a high degree of accuracy.
  • If so, have you checked out how far trees at the "left horizon" are vs the "middle horizon" vs "right horizon"? My experience is there is a definite "learning curve" to estimating distances, but with practice you can get pretty good at it ... such as golfers and hunters.
  • Are those distances within +/- [fill-in-the-blank]?
  • ....
  • OT?
    I've been pondering how much "field curvature" and "focus shift when stopping down" (which this example doesn't do) really matter with the relatively large DOF of a f/2.8 lens and relatively wide 35mm FL. Even with a very small CoC, I doubt even a large print or the DPR Loupe would have these issues be noticeable ... if you print full frame.
  • However, those issues seems maybe relevant for non-IQ test images if you need to crop the image for a print or upload ... then the effective CoC can be truly minuscule.
 l_d_allan's gear list:l_d_allan's gear list
Panasonic Lumix DMC-TZ3 Panasonic Lumix DMC-FZ47 Canon PowerShot S110 Canon EOS 5D Mark II Canon EOS 600D +27 more
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