vincentbihler
Member
Indeed, looks very sharp from corner to corner and the optics look to be handling high contrasts scenes quite well!
[New test photos released] Leica Summicron 35/2 Eight Element copy made in China
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raid
Dad Photographer
Now is the time to be hearing good news about the process of lens orders and delivery. The replica lens is obviously an excellent lens overall.
retinax
Well-known
What's going on here? At full resolution, there's a very mushy looking zone in the trees on the right, and then near the corner, it gets sharp again! I don't see this on the left side, which is probably because it'scloser, but I also don't see it in the other pictures. Any chance this was actually shot at a wider aperture? The EXIF aperture estimate thinks so, it shows 2.4. This seems to conform to the MTF graph posted somewhere here, but I didn't expect it to be this visible, especially at f/5.6 or 8. Must be an effect of a strange, complex field curvature?
Here in northern Vermont, we just had a couple of days of storm, and today the sun came out. There is little up here usually to take pictures of this time of year, but I took out the 8-element prototype and shot a series of images of snow on the trees. M10, ISO 200, either f/5.6 or f/8. Only in bit of exposure brightening in PS, one image is cropped slightly.
See what you think.
Ed
L1003780 by woodswoman57, on Flickr
L1003776 by woodswoman57, on Flickr
Also seems to be a quick transition from sharp to mushy in the upper right corner, if you download the full image file from flickr
raid
Dad Photographer
What does this all imply about the lens? Was it the scan or the lens or the camera?
Ed Schwartzreic
Well-known
I still have the file on my SD card, and having only a short time right now to respond, I looked at it on th M10’s view screen, and zoomed in. This appears much sharper in those tree branches than what I see in the flickr image. Of course this may just be the camera optimizing a jpeg.
Later I will again off-load the file and have another look at it in LR or PS.
Ed
Later I will again off-load the file and have another look at it in LR or PS.
Ed
raid
Dad Photographer
It is most likely something that happened in the file uploading to Flickr or similar issue. I once had a similar problem, but DAG identified it as a lens element inside the Canon 50/1.2 LTM having moved! Parts (front, back, left, right) of the image would be sharp and then some parts would be blurry. Don moved the lens element back into its correct place, and the lens was sharp again across the image plane.
punkzter
Established
I feel like I'm missing something here. I'll wait for someone to correct me. But, I figured that in the past people just weren't shooting wide open. I suppose they could have used slower films, but in general, I assumed that shooting outside meant that you weren't shooting wide open most of the time. Especially give the max shutter speed of 1/1000.
Are we really to think that these lenses were designed to be shot wide open when most of the time the'd be around f/8?
Thanks!
Brad
Also is some weirdness in the upper left corner of this one. Again, a quick transition from sharp to fuzzy. This one appears to have been cropped? as the dimensions are different from the other photo linked above.
L1003778 by woodswoman57, on Flickr
L1003778 by woodswoman57, on Flickr
raid
Dad Photographer
It could be that Leica was focusing on indoor photography for journalists where shooting wide open was a requirement. Try using f8.
mpaniagua
Newby photographer
One point to consider is that film where slower before , so getting a picture of a shadow area with a fast speed (since we are talking about news and fast action photography) required to use a wide apperture.
Regards
Marcelo
mpaniagua
Newby photographer
Agree. We are talking about indoors news conference and the like. No flash either.
Marcelo
raid
Dad Photographer
In old times, film sensitivity was very low. I once had a LF lens 362mm with max aperture 1.66. The lens was huge. The camera was used during WWII. Film sensitivity may have been ISO 10 then.
Huss
Veteran
Could it be wind in the trees?
Huss
Veteran
Problem is that can be tough outside w a max shutter speed of 1/1000 sec. Even with an ND filter.
Ed Schwartzreic
Well-known
A partial answer to several questions. Yes, the max film speed which reporters usually used was 400 for Tri-X, which sometimes was pushed to 800 or 1600. One needed f/2 or f/1.4 often inside or in situations where one also needed a speed of 1/125 or higher. Some times it was f/2 @ 1/25 sec and be there, other times it was f/2 at 1/250 where there was action.
An then you might be caught in a very bright environment and really need a slower film, so one either pulled out another camera body, or rewound the film and reloaded. Just as one tried to prepare for the assignment wth the proper focal length lenses and film speeds, one had to be prepared to the unforseen. It is so much easier with digital.
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Yes, that one image was cropped, as I had originally said. I also checked the lens for any smudge or other artifact, and also looked at my sensor. Both were clean.
Yes there could have been wind. The EXIF only said 1/3000 sec and ISO 200, but that speed ought to have been enough to stop motion in the field.
Later today or tomorrow I will look at the files again.
Ed
An then you might be caught in a very bright environment and really need a slower film, so one either pulled out another camera body, or rewound the film and reloaded. Just as one tried to prepare for the assignment wth the proper focal length lenses and film speeds, one had to be prepared to the unforseen. It is so much easier with digital.
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Yes, that one image was cropped, as I had originally said. I also checked the lens for any smudge or other artifact, and also looked at my sensor. Both were clean.
Yes there could have been wind. The EXIF only said 1/3000 sec and ISO 200, but that speed ought to have been enough to stop motion in the field.
Later today or tomorrow I will look at the files again.
Ed
retinax
Well-known
It's not wind. Wind would be more visible on branches closer to the camera and less on those further away, more on thin branches and less on thicker ones.
And it wouldn't be only in the zone where the MTF graphs in post 1553 predict lower resolution! More clearly visible: The zone where resolution is high again before it drops off in the extreme corner is exactly where the bump is in the MTF graph, around 17mm out. This is the lens, and apparently the original does it too. It must be complex field curvature.
I was just surprised to see this so clearly in this picture which Ed wrote, mistakenly, had been taken at 5.6 or 8. It's in fact taken at a wide aperture, so it's ok, landscapes at wide apertures can't be expected to be sharp anyway because of limited dof. Curious to see what it looks like in closer, more typical wide-open situations though. It would be cool if someone who has the original or replica could post a shot down on something with a regular pattern, like a tiled floor, extending away from the camera. I think we'd see a more or less mustache shaped "plane" of sharpness.
Ed Schwartzreic
Well-known
I looked at that image with the fuzzy to sharp transition, and a couple of others which I had not uploaded, as raw files. The issue definitely was there in all three of my files that I examined. I don't know what to say about the cause, but I guess I will make the excuse that my lens was a prototype, and not the finished product. I had two prototypes to test, so I do not know whether this was an issue with the other one (which is now elsewhere).
Perhaps someone on the thread in China who has a production lens could try to see if anything like this happens with their example. A mystery.
Ed
Perhaps someone on the thread in China who has a production lens could try to see if anything like this happens with their example. A mystery.
Ed
raid
Dad Photographer
I hope that there is no lens design error in the way the lens elements have been placed.
retinax
Well-known
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