180-600 Disappointment!

[SCoombs]

Right on.. we have these 45mp sensors, we should be able to crop and enjoy them, right?! I always hear that 300-400 is good for BIF, and then see people posting frame-filling ducks/birds/owls. I never thought to ask/check the image size or how much they cropped, but it'd be interesting to see the workflow from someone who does more BIF.

Anyways, I did some quick tests just now b/w the 186 and 600PF. Did 3 distances (9, 18, 34 yards as measured with my laser rangefinder), with a shot at center and edge of frame for each, compared at 200%. At 9yds, both lenses are comparable in the center, and as we move to the edge the prime is a bit sharper. We already knew this, no surprise there, but here's some interesting info for you: at the 18 and 34yd distance, the 186 is noticeably softer even in the center, and the edges degrade even worse, becoming very soupy at 34 yards. I'd say that it supports your hypothesis that the zoom is losing resolving power as the distance increases.

In summary, this is some of what the $3200 price difference is getting you. How often will this impact your photos, probably rarely to never, and in a vacuum, you’d be perfectly happy with how the 186 performs. After owning both lenses for quite a few months now, seeing the differences for myself is eye-opening, but it won’t in one bit alter my view of the 186.

I get it, jpeg screen grabs uploaded to a non-Pro Flickr account and then posted here aren't going to show the best detail, but hopefully it shows enough of the difference. If one really wants to compare them, you have to do it with the RAW files at home on your system, so anyone wants these files to see for yourself, PM me and I'd be happy get them over to you.

34 yards at the center (600PF on the left, focus is on the eye in all photos):
34yd-center by M K, on Flickr

34 yards at the edge (600PF on the left):
34yd-edge by M K, on Flickr

For fun, here's the comparison shots at 9 yards, again, 600PF on the left:

Center:
9yd-center by M K, on Flickr

Edge:
9yd-edge by M K, on Flickr

First, thanks for putting I this effort as I appreciate it a lot.

Second, I do see a difference there but frankly it's very minimal compared to what I've come to expect. I'm going to set up a target like this at 34 yards later today and I think I'll be shocked if I get anything even remotely close to as good as we see from either of your lenses.

 

[Len Shepherd]

There can be a significant challenge difference between a test shot of a static stuffed subject - and images of a small bird

Shot at 480mm as the Siskin was closer than the MFD of the 180-600

The crop I consider OK - for hand held.



View attachment 84066

 

[SCoombs]

I need to ask before posting some of my samples if I am understanding what people mean when, as Matthew, they say they're posting at 200%. I also know Steve does this in some of his comparison and sharpness testing videos and like Matthew's lion toy here the photos look fine. Does this mean moving the zoom slider in Lightroom to 200%, or does it mean something else? I ask because I have never, ever in my life seen a photo with that zoom slider at 200% that looked anything remotely close to what I see in Steve's videos or Matthew's lion there. This is regardless of lens - including at least on S line lens of my own and also including RAW files from other photographers using very nice lenses. It's not that none of the photos I've seen look very sharp with that slider at 200% - it's qualitatively different from that. It's that they're pixelated because they've been zoomed to the point where each pixel recorded in the image is being blown up to cover multiple pixels when displayed. Yet when Matthew here and Steve in his videos talk about "200%" they look fine.

So I'm confused here not about the comparison of our lenses, but at how people are saying they're posting a zoom at 200% yet it still looks like a normal photo.

 

[Nimi]

Right on.. we have these 45mp sensors, we should be able to crop and enjoy them, right?! I always hear that 300-400 is good for BIF, and then see people posting frame-filling ducks/birds/owls. I never thought to ask/check the image size or how much they cropped, but it'd be interesting to see the workflow from someone who does more BIF.

Anyways, I did some quick tests just now b/w the 186 and 600PF. Did 3 distances (9, 18, 34 yards as measured with my laser rangefinder), with a shot at center and edge of frame for each, compared at 200%. At 9yds, both lenses are comparable in the center, and as we move to the edge the prime is a bit sharper. We already knew this, no surprise there, but here's some interesting info for you: at the 18 and 34yd distance, the 186 is noticeably softer even in the center, and the edges degrade even worse, becoming very soupy at 34 yards. I'd say that it supports your hypothesis that the zoom is losing resolving power as the distance increases.

In summary, this is some of what the $3200 price difference is getting you. How often will this impact your photos, probably rarely to never, and in a vacuum, you’d be perfectly happy with how the 186 performs. After owning both lenses for quite a few months now, seeing the differences for myself is eye-opening, but it won’t in one bit alter my view of the 186.

I get it, jpeg screen grabs uploaded to a non-Pro Flickr account and then posted here aren't going to show the best detail, but hopefully it shows enough of the difference. If one really wants to compare them, you have to do it with the RAW files at home on your system, so anyone wants these files to see for yourself, PM me and I'd be happy get them over to you.

34 yards at the center (600PF on the left, focus is on the eye in all photos):
34yd-center by M K, on Flickr

34 yards at the edge (600PF on the left):
34yd-edge by M K, on Flickr

For fun, here's the comparison shots at 9 yards, again, 600PF on the left:

Center:
9yd-center by M K, on Flickr

Edge:
9yd-edge by M K, on Flickr

Great analysis, thank you.

 

[MatthewK]

First, thanks for putting I this effort as I appreciate it a lot.

Second, I do see a difference there but frankly it's very minimal compared to what I've come to expect. I'm going to set up a target like this at 34 yards later today and I think I'll be shocked if I get anything even remotely close to as good as we see from either of your lenses.

Well, I had to dig down to 200% before I could see any differences. Real life, this will never be of any relevance.

There can be a significant challenge difference between a test shot of a static stuffed subject - and images of a small bird

Shot at 480mm as the Siskin was closer than the MFD of the 180-600

The crop I consider OK - for hand held.



View attachment 84066

I tried all day to get a shot of the same bird, in a decent pose, with both lenses, but they wouldn’t sit still long enough while I changed lenses I got close with some Grackles yesterday, but in the end it was just easier to use Stuffed Simba.

Even if I had been able to get a bird to sit through a portrait session, I can guarantee there’d be no noticeable difference in how the lenses performed. Remember though: my intention with the test wasn’t to compare lenses for sharpness, but whether or the zoom lost any fidelity compared to the prime as the subject got farther away and/or smaller in the frame.

I need to ask before posting some of my samples if I am understanding what people mean when, as Matthew, they say they're posting at 200%. I also know Steve does this in some of his comparison and sharpness testing videos and like Matthew's lion toy here the photos look fine. Does this mean moving the zoom slider in Lightroom to 200%, or does it mean something else? I ask because I have never, ever in my life seen a photo with that zoom slider at 200% that looked anything remotely close to what I see in Steve's videos or Matthew's lion there. This is regardless of lens - including at least on S line lens of my own and also including RAW files from other photographers using very nice lenses. It's not that none of the photos I've seen look very sharp with that slider at 200% - it's qualitatively different from that. It's that they're pixelated because they've been zoomed to the point where each pixel recorded in the image is being blown up to cover multiple pixels when displayed. Yet when Matthew here and Steve in his videos talk about "200%" they look fine.

So I'm confused here not about the comparison of our lenses, but at how people are saying they're posting a zoom at 200% yet it still looks like a normal photo.

Mine are actually screen grabs from my Mac showing the Lightroom comparison. An actual 200% crop of a file would be a disaster haha

 

[SCoombs]

Mine are actually screen grabs from my Mac showing the Lightroom comparison. An actual 200% crop of a file would be a disaster haha

Hmmm, I'm talking about what the screen shows when selecting 200%.

 

[SCoombs]

I did some of the same sorts of tests as Matthew this afternoon. Initially I did a bunch with a stuffed toy, but eventually I decided to use a street sign instead as it was easier to keep things uniform. I did this by positioning myself at 3 specific points on the street and then photographing the same sign at 5.6 and 8.0 on my 200-500 in the center and on the edge. Then I did so at 6.3 and 9.0 on my 180-600. I also repeated the test with the 180-600 at both 500mm and 600mm. I used AF-S pinpoint autofocus. I did change one thing up between tests, using 1/500 for the 500mm shots and 1/640 for the 600mm shots and I did use VR for this. I'd like to have had a VR-less test but with the lighting today I wanted to keep the shutter speed lower if possible. In Lightroom, I did no editing except that I cropped every photo to the width of the street sign.

My observations are that there is not as much of a difference in these tests as I expected between the two lenses and the 180-600 is appearing at least as sharp in some cases if not more than the 200-500 while in others it is not.

Here is a comparison at 38 yards (measured by hand) and wide open at 500mm. The 180-600 is on the left. My impression is that the 180-600 is slightly sharper here.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

Meanwhile, here is wide open at 61 yards:

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

As it may be easier to see, here is a comparison of a stuffed toy. These are 100% crops at between 8-10 yards, each lens stopped down as somehow I apparently didn't take a wide open shot on the 200. 180-600 on the left. My impression is that the 200-500 is slightly sharper here.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

I have also observed something that I'm not sure what to make of as I was working on this: the EXIF data is reporting drastically different focus distances for my 180-600 vs my 200-500 when shooting the same target from the same spot with the 200-500 being closer to reality.

I shot the sign from 3 places which I measured by hand to be 38 yards, 48 yards, and 60 yards. The 200-500 reports these shots as being at 32 yards, 44 yards, and 61 yards. Meanwhile, the 180-600 reports these same distances as 48 yards, 61 yards, and infinity. The 180-600 measures this the same regardless of the focal length it is zoomed to.

Intrigued, I tested the same distances with my 70-180Z and my 85 /1.8Z but these both reported all of the distances as infinity. I presume this is because the distances were all far enough away to be at infinity as far as those particular lenses were concerned, but I'm not sure what to make of the 180-600 and 200-500 reporting such different measures and what if anything that has to do with how they are focusing or focus accuracy.

 

[Marcepan]

The results indicate that both lenses are in the same optical class and the differences between them are minimal. Looking at the mtf charts on the Nikon website, we can see that 200-500 is sharper in the very center and 180-600 in the area outside the center (at the long end).
Remember, however, that we cannot compare these two graphs 1:1 because they do not take into account the diffraction f5.6 vs f6.3. In practice, the sharpness advantage of 200-500 in the center - should be slightly greater than 180-600, and in the remaining part of the frame - the advantage of 180-600 should be slightly smaller.

To sum up - similar optical class and minimal differences in optical image quality.

 

[Len Shepherd]

I tried all day to get a shot of the same bird, in a decent pose, with both lenses, but they wouldn’t sit still long enough while I changed lenses I

One of the challenges of testing a lens with small birds is that they move fast in proportion to their body size and leave you struggling between enough magnification, enough depth of field and a fast enough shutter speed even with recent high ISO processing.
A good test chart or other static subject suitable for accurate AF acquisition normally clarifies whether a lens is sharp or not.
I think we both agree getting critically sharp shots of small birds is much more challenging than getting critically sharp shots of a static test subject.

 

[MatthewK]

Well, now that that's settled, let's go out and make some great images, shall we?

 

[SCoombs]

After more shooting, I'm reaching the conclusion that while this isn't the sharpest lens on the shelf, the biggest issue I'm facing is autofocus inconsistency, something that I know can sometimes be an issue with consumer grade lenses. FoCal did report lower than average focus consistency and I can see in my shots a lot of cases (in situations/locations where haze should not and has never before been a factor) where you can see the focus plane shifting over the course of a sequence of shots resulting in some being sharp and others being a bit soft.

The FoCal people have a good read about how one of the reasons mirrorless cameras can sometimes benefit from AF fine tuning is that lenses will have a range of focus positions that their motors will land on around any given focal plane and sometimes a given lens - especially ones that are not top of the line - will have a larger range meaning that if on a given shot the lens landed on one of the ends of the range rather than closer to the middle you can get a shot that isn't as sharp as it ought to be, the idea being that AF fine tuning on mirrorless can help to move that range so that the motors are more likely to put the focus on a place closer to the target.

In any case, I'm getting the sense that this is what's happening here. One thing I haven't mentioned yet is that before I posted in this thread I'd already been experimenting with the AF fine tuning to try to improve the sharpness. FoCal keeps recommending +1 or +2, but today I went out and had the best success just leaving it at 0. I feel like there is inconsistency here but am working on figuring out how to set things up to get the best results. Here we have some examples of shots that I considered to be reasonably sharp from this morning.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

That starling is actually one I'm not super happy about but it's not the fault of the lens - it was actually very dark and I had to bring it up a lot which means the bird itself doesn't have the best look.

 

[ajrmd]

Glad to hear you are warming up to this lens. I was fortunate to have it today and unlike the operator, it never failed.

You can only see EXIF info for this image if you are logged in.

 

[ARClark]

Glad to hear you are warming up to this lens. I was fortunate to have it today and unlike the operator, it never failed.

View attachment 84385

Gorgeous shot!

 

[ajrmd]

Gorgeous shot!

Thank you! Who said the Z8 can't focus on long necked birds? Yes, it struggles with GBH and other herons at times, but for these guys/gals it was nailing them >90%.

You can only see EXIF info for this image if you are logged in.