400 f/3.5 IF-ED on Fuji X-T1 soft images

[rosario_turrisi]

<p>Hi,<br /> supported by many nice reviews I grabbed the chance to buy this 400mm for a nice price. Adapted to a Fuji X-T1 with a cheap ring (which does not show any issue) I tried to get sharp images with no success. The camera is working fine, I have amazing shots with the 56 f/1.2, the 23mm and the 14mm and when there is something wrong I can clearly blame myself. <br />Few days ago I spent a couple of hours in a natural reserve. Shooting times always (except for a few cases) between 1/2000 and 1/4000, at 400 ISO (sometimes 800). Many pictures are taken with the camera on a sturdy tripod (Manfrotto 075) or with the lens handheld but supported by a wood fence.<br /> Here the results:<br /> https://www.dropbox.com/sh/8qoy2e04y0gyury/AAD2gwDkY1glmnc5EQPdsrf6a?dl=0<br /> Minimal postproduction, just a little bit of sharpen with PS CS6. PSD files generated with C1 from the original raf. <br /> Clearly the combination lens-camera is not working properly but I am clueless about the possible reason, any hint?<br /> Thanks a lot,<br /> Rosario</p>

<p>ps I also tried a Nikkor 400 f/2.8 AF of a friend, pictures 80-87, results look very close...</p>

[kari_oinonen]

<blockquote>

<p>Clearly the combination lens-camera is not working properly but I am clueless about the possible reason, any hint?</p>

</blockquote>

<p>With some of your subjects you have been quite far away. I could see some back focused bee eaters - see the branch. Some single bee eaters were clearly sharper than the other.<br>

I'd try to check these four:<br>

1. Are you expecting too much sharpness at pixel level?<br>

2. Focusing - is sensitive and can be difficult to do exactly right. I have seen some kind of manual focus aids like studs at the focusing ring in the old days of big manual focus lenses.<br>

3. If your adapter has not an optimal thickness (axially) then that may lead to similar lowered(?) sharpness with yours and your friends lenses. Is the adapter just a mechanical one without any optics?<br>

4. And a test suggestion. Set your rig at a firm table, focus to your subject and trip the shutter by timer not touching the rig nor the table. This can give you one reference more, eliminating the tripod and your right hand from the sharpness equation.</p>

[John Crowe]

<p>It is not possible to compare results from wide angle and normal lenses to supertelephotos unless you use very controlled methods. So you may be overestimating what the 400mm is capable of. If you had another inexpensive telephoto zoom to compare to that would be easier. I have a 400/2.8 and they are extremely sharp so the fact that you say your 400/3.5 is similar is a good sign. Keep in mind the extremely narrow depth of field of these lenses, and the need for critical focus.</p>

<p>In many of your images the subject is extremely small in the frame and thus requiring a lot of cropping and at 16 MP this can be pushing the limits. Most of your images are likely what I would expect from a 400mm lens but again difficult to really tell. </p>

<p>While the 400/3.5 is not soft wide open you will see considerable more sharpness at f5.6.</p>

<p> </p>

[rosario_turrisi]

<p>Hi Kari,<br>

thank you for taking time to see the pictures!<br>

1. I see some shots made with the same lens model and less performing cameras looking much better...this is not quite ''scientific'', trying to have my lens tested on another aps-c camera, like 7100<br>

2 I have focus peaking, digital split and magnification. Sometimes I fail, but have hard times trying to find any well focussed point...<br>

3,4 Will check!<br>

Thanks a lot!</p>

 

[rosario_turrisi]

<p>Thanks John. I was just makeng the point that the camera does not show clear issues. And you are definitely right, should compare same focal lengths.<br>

Usually I check the images at 100%, whatever the subject. I have seen pictures taken with a FF, same number of MP, and it looks way better.<br>

The images I link are not cropped. <br>

Maybe it is just the limit of the camera... </p>

[dave_wilson1]

I use the 400mm 3.5 all the time. Check the filter in the removeable cartridge and make sure it is perfectly clean and not

fogged. Don't use lens tissue it makes fibers, prefer use a pure piece of chamois and a huff of breath is good enough.

Next with a flashlight shined through the front, check the recessed rear element for dirt or residue. If it's dirty this is a trick to clean.

Use a long stereo-cleaner q tip and a little bit of alcohol or even vodka is good on the q tip and in two steps, immediate,

right after each other: First gently swab the rear element with the q tip, then with a second one, cut a very small piece of

cotton under shirt, about an inch square, fold it over the tip in a ball and tape it around the wooden shaft, this will be to

quickly dry and polish the rear element. Practice first on something else to get the hang of it, like the back of a shot glass

in a paper towel tube. As an alternate, you could also cut and secure a small piece of chamois around the end of a pencil eraser. Just fold it around and tape secure to the pencil shaft.

[john_hinkey]

<p>Your images that seem to achieve good focus look pretty good to me. The 400/3.5 is pretty good, but on the high MP of the Fuji it's asking too much for pixel level sharpness. Especially for birds - the fine details in the feathers are easy to see when they aren't resolved well. I don't thing there is anything wrong with the lens - it's just a matter of accurate focusing and realistic expectations of a pretty old lens design.</p>

[User_1172872]

<p>It's possible the combination just won't work well. The following may be of interest:<br>

http://www.lensrentals.com/blog/2014/06/sensor-stack-thickness-when-does-it-matter<br>

Short version: every digital camera has a 'sensor stack' consisting of the anti-alias and IR cutoff filters. The sensor stack varies in thickness among camera brands, which <strong><em>may</em> </strong>affect the results when using lenses of different brands via adapters.</p>

[lex_jenkins]

<p>Adapting Nikkors to the Fuji X-system involves compromises that will show up in our photos.</p>

<p>For one thing, the adapters are rather long. In my own photos I see three problems from using Nikkor and Nikon F mount telephotos on the Fuji X-A1:</p>

<ol>

<li>Chromatic aberration and astigmatism seem worse than with the same lenses on Nikon bodies. Presumably this is due to the long adapter altering the convergence of light rays.</li>

<li>The long adapters are cheap and cheaply made. Any slight defect in machining may throw off sharp focus along one edge/corner.</li>

<li>I don't know about the X-T1, but the low end X-A1 has an inexpensive, flexible plastic body supporting the metal lens mount ring. The adapter fits rather loosely, so even if the adapter itself was squared up and precisely made, the mediocre fit would compromise results with longer, heavier lenses.</li>

</ol>

<p>Some of the older Nikkors were as well made as they could be for that era, but even some entry level kit zooms -- at least within their sweet spots -- can surpass the older Nikkors in correction of chromatic and spherical aberration, reduction of flare along with improved contrast and apparent sharpness.</p>

<p>And a high resolution digital sensor will reveal flaws that were not apparent in film. That's the first thing I noticed with the 28/3.5 PC-Nikkor on the 4 mp D2H -- much more apparent chromatic aberration around high contrast areas, compared with my earlier film results. Adding the inexpensive adapter between the PC-Nikkor and Fuji worsens the flaws, particularly in softness along one edge/corner. Again, that's a flaw inherent to the X-A1's plasticky body. The X-T1 may have a more rigid body and fewer problems with a precision made, good fitting adapter.</p>

[rosario_turrisi]

<p>Thanks a lot everybody for the answers. I can perform a few tests to exclude simple issues, but clearly is not obvious to quantify all the factors building up the result. <br>

What is clear, is that I have to find a better solution to have a decent telephoto of about 600mm, until Fuji puts on the market the 100-400.</p>

 

[john_hinkey]

<p>For a 400mm lens the general use of an adapter or sensor cover glass thickness won't make a big difference. Many of these older tele lenses just don't have the resolution to give pixel level sharpness on today's digital cameras. As far as adapter quality goes, I've measured my expensive metabones F to Sony E adapter and it had much variations in dimensional tolerance than my cheap fotasay F to E adapter - so it all depends on the specific copy you have. I would say using such a lens on a less-than-full-frame sensor high pixel pitch sensor has the following problems:<br>

- Older lens designs not having the sharpness to satisfy such a sensor and/or low in contrast/high in CA <br>

- Reflections of the light the lens shines outside the sensor area (full frame illumination on a APS-C (or m43) sensor area) - what happens to that light and does it cause loss of contrast? This could be a combination of camera body light baffling and adapter baffling<br>

- IF the lens is sharp enough across the image plane, then lens mount - adapter mount parallelism to the sensor may be noticeable depending on the degree of non-parallelism, which plane it's in, how the adapter/body are loaded/flexed from the body/lens/adapter weight, and aperture used, etc. For example, my Zeiss 135/2 APO clearly shows that the lens mount on my D800 needs adjustment as the right edge is slightly out of focus compared to the rest of the frame, while using it on my A7r and m43 bodies shows no such focus issues. My less sharp lenses can't see this issue.<br>

- Focusing - it's really tough with some of these older lenses to really nail the focus - the DOF is thin and the focusing helicoids can be on the coarse side for fine adjustments</p>

<p>That's my take anyways.</p>

<p>John</p>

[john_hinkey]

<p>Just to clarify, when I stated that a 400mm lens won't be affected by cover glass I base that on the lens-rentals article that showed the effect of exit pupil distance on the degree of degradation by a thick sensor cover - the more distant the exit pupil the less the issue. A 200mm exit pupil shows little degradation.<br>

One other thing is sensor reflections. How the light reflections off the sensor (digital sensors are far more reflective than film) interacts with the lens can be an issue as well, though for long teles this might not be much of a problem.</p>

[nathan_wong2]

<p>My Nikkor 400mm f/5.6 wasn't giving me ultra sharp images when I first purchased it. After some time I ended up looking down the barrel and saw the element was filled with caked on dust. I got a cleaning cloth, a long stick (chopstick) and cleaned the element. That made a world of difference and now my photos are rather sharp. Might want to take a look at that. It won't hurt and it only takes a moment of your time. </p>

[donbright]

<p>I think, in fact I know, it's not the lens!</p>

<p><img src=" alt="" />

[rosario_turrisi]

<p>Hi Don,<br>

I love the picture, while I find it a bit soft, but one cannot really draw conclusions on a jpeg 1024 pixel wide. My camera issues 4896x3264 files, should put side by side 100% crops...<br>

I had on my monitor pictures taken with the 500 f/4 af-s Nikon, and already from the jpegs you guess it's a beast. Of course cannot compare such a lens with my 400, but I cannot believe the quality I get is closer to that of a mirror lens...<br>

Again, congrats for the picture, imagine was not obvious to spot the subject...and, wow, Velvia, reminds me of the ol' good times :)</p>

 

[alan_wilder1]

<p>I checked out your dropbox images and I'm not sure what you consider as "soft". Your shooting speeds and ISO seem fine. I use my 600/4 AFS with my Fuji XE-2 and IQ is fine to my eye. Are you using the camera's focusing aid for exact focus? I use the standard view 10X magnification aid as it's more accurate than their digital split-image or focus peaking aids. The 400/3.5 is far sharper than any lens Fuji will introduce in a zoom form but obviously it is going to be preferable in size and AF capability.</p>

[donbright]

<p>All of my images posted here look soft compared to my library. If there's a way around that, I would surely like to know.</p>

[rosario_turrisi]

<p>Hi Don, <br>

I think it is downsampling which causes a loss of detail. Still, I love your shoot... :)</p>

 

[rosario_turrisi]

<p>Hi Alan, <br>

let's put it like that: if I try to find where the focus is, I'm never sure. When I identify I have the impression (really strong impression, say I'm pretty sure) that pictures taken with the 55-200 fuji are better looking. Of course it is a different focal length, but if I magnify to 2-300% I can see the pixels, but the image looks sharp, in the sense that details are there. The same I can't tell about my pictures. And shoots taken with the same lens (same kind, not properly mine) with other cameras have a completely different feeling concerning sharpness. Again, a serious test should be with the same lens and different cameras with similar sensors, and looking at 100% crops from raw files, what up to now I had not the chance/time to do. What I can tell is that pictures taken by a friend of mine in the same situation with the nikon 400 2.8 on a D4 (the 16.2 MP) are way better than my best pictures...</p>

[alan_wilder1]

<p>Hi Rosario,<br>

I'm confused by "let's put it like that: if I try to find where the focus is, I'm never sure."<br>

Are you focusing at f/3.5 and using the "standard view" at maximum magnification (10x?) with the MF Assist mode? Exact focus within the magnified rectangular box is very easy to assess but it should be placed exactly within the spot you want perfect focus, for example the eye of a bird. Anything outside the magnified rectangle that doesn't share the same focusing plane will be soft since you are effectively dealing with a 600/3.5 with razor thin DOF. Again make certain the aperture ring is set for f/3.5 wide open, not for example stopped down to f/22 as this will make it much harder to nail exact focus.</p>