Technical Camera Images

[Rod S.]

I think some of this is due to changing expectations as sensor technology developed -- rather than changes in the lens itself.

@Rod S. has an excellent collection of S-K material. If he sees this conversation, I'm hoping he can resolve this mystery.

SK introduced its new range of lenses for digital photography at Photokina 1998. The line was called 'Digitar'.

The shortest focal length lens of symmetrical design in the line was the Digitar 5.6/47.

(The single shorter lens in the range was the Digitar 2.8/28, a retrofocus lens.)

As we have discussed a number of times, the lens design was adapted from the earlier Super-Angulon 5.6/47 rather than the later Super-Angulon 47XL of 1994.

The digital sensors on the market at that time were small, 24x36mm or 31x31mm or similar, and those sizes drove the expectations for the required image circles.

Accordingly, the SK technical sheet for the 5.6/47 gives the format as 30 x 30mm and the diagonal as 60mm. Those dimensions are that of the category, as opposed to the 6x9cm or 4x5 inch or 5x7 inch categories that everyone was accustomed to and were still being made. Those dimensions then drove the image area shown on the MTF graphs.

The image circle of the 5.6/47 lens was first stated as 113mm in the SK brochure for digital lenses of September 2004, by which time the lens was renamed as the Apo-Digitar 5.6/47XL (thereby matching the designation of its siblings). SK didn't reveal the basis for that 113mm size nor update the technical sheet. Perhaps the 113mm came from a technical sheet that was prepared but never published, or from inspection of images made with the lens.

 

[mristuccia]

SK introduced its new range of lenses for digital photography at Photokina 1998. The line was called 'Digitar'.

The shortest focal length lens of symmetrical design in the line was the Digitar 5.6/47.

(The single shorter lens in the range was the Digitar 2.8/28, a retrofocus lens.)

As we have discussed a number of times, the lens design was adapted from the earlier Super-Angulon 5.6/47 rather than the later Super-Angulon 47XL of 1994.

The digital sensors on the market at that time were small, 24x36mm or 31x31mm or similar, and those sizes drove the expectations for the required image circles.

Accordingly, the SK technical sheet for the 5.6/47 gives the format as 30 x 30mm and the diagonal as 60mm. Those dimensions are that of the category, as opposed to the 6x9cm or 4x5 inch or 5x7 inch categories that everyone was accustomed to and were still being made. Those dimensions then drove the image area shown on the MTF graphs.

The image circle of the 5.6/47 lens was first stated as 113mm in the SK brochure for digital lenses of September 2004, by which time the lens was renamed as the Apo-Digitar 5.6/47XL (thereby matching the designation of its siblings). SK didn't reveal the basis for that 113mm size nor update the technical sheet. Perhaps the 113mm came from a technical sheet that was prepared but never published, or from inspection of images made with the lens.

Thanks Rod for the historical hints.

But does anyone know what kind of IC diameter should be expected for real from that lens? And what is the MTF according to that IC?
Any hands-on experience?

 

[John Leathwick]

I have three different PDF data sheets for the 47, including the Alpa one for the "Helevetar". In all three, the lens parameters are exactly the same. Interestingly, in none of these data sheets is it called XL. Nonetheless, I have heard the claim that the XL version is different.

This link is to the online version on S-K's site from a 2005 crawl by the Internet Archive. The data are the same as the PDF sheets. https://web.archive.org/web/2002080.../photography/digital_photography/47/page1.php

I'm curious if anyone has an "XL" data sheet that has lens characteristics that are different from the PDFs I have (one from Dave's site) and this web version.

I have an S-K brochure of intermediate age that includes this table describing two very different Super Angulon 47/5.6's. The values are front diameter, minimum aperture, filter size, shutter size, flange focal distance and rear mount diameter.

-John

 

[rdeloe]

I have an S-K brochure of intermediate age that includes this table describing two very different Super Angulon 47/5.6's. The values are front diameter, minimum aperture, filter size, shutter size, flange focal distance and rear mount diameter.

-John

View attachment 225149

That matches my info. One is the "MC" and one is the "XL" Super-Angulon. They are different designs.

 

[Rod S.]

We should work on a unified table with all data and all equivalences between the various rebranded LF/MF tech lens models, and keep as a valuable resource in this forum, which is the most specialized on such subject...

I understand the desire to simplify the complexity by inserting lens parameters into a single reference table.

However, the complexity arises because the lens lines from both Schneider and Rodenstock evolved over time, and at different intervals over time.

The evolution of different lens lines is difficult to capture adequately in a single table. Such single tables tend to scramble everything and make understanding much more difficult.

The best way to understand the evolution of the lens lines is to read the successive brochures from the manufacturers themselves.

 

[Rod S.]

I have an S-K brochure of intermediate age that includes this table describing two very different Super Angulon 47/5.6's. The values are front diameter, minimum aperture, filter size, shutter size, flange focal distance and rear mount diameter.

-John

View attachment 225149

John, that table is from the Schneider lens brochure of 1995, which introduced the new Super-Angulon XL range alongside the existing Super-Angulon range.

 

[Rod S.]

Thanks Rod for the historical hints.

But does anyone know what kind of IC diameter should be expected for real from that lens? And what is the MTF according to that IC?
Any hands-on experience?

In my opinion, the sizes of the image circles given by SK in its 2004 brochure are, with the exception of the oft debated 35XL, a good indication.

Surprisingly so, given the subsequent increases in sensor size and pixel count.

I haven't tried to determine the IC diameter for myself.

 

[Rod S.]

We are discussing the 47XL in the Technical Images thread. It could helpfully be placed in a separate thread.

 

[rdeloe]

We are discussing the 47XL in the Technical Images thread. It could helpfully be placed in a separate thread.

I'm not sure our mod team has the bandwidth to move posts around, but if they do this would be a good place (the thread from the last time this question came up): https://www.getdpi.com/forum/index.php?threads/schneider-digitar-5-6-47mm-different-versions.70615/

 

[mristuccia]

I've moved the entire conversation on that thread as quotations.
If the mod team will move the real posts, I'll remove it.

 

[miriquidi]

The best test is to find a reference you trust. Could be a building or in my case a very accurate level. Then find out how that bubble level you use is off. Write it down and keep it with you so you can reference your reference.

Of course, that's only half the battle. You need to figure out how to get the camera position square to the subject, at least when that is important. For that, I just do the best I can using the subject and the frame lines in live view. You can obviously tether when it is critical. I assume you are using some sort of geared tripod head with a leveling base. That allows you to level the head and use the gears for fine adjustment.

There are no marks on the bubble heads. China stuff. I mostly shoot handheld, seldom with an old ball head tripod.

My answer mirrors Dave's. I have two levels on the Cube and two on my F-Universalis, and they don't agree with each other or with my Stabila level. The level in my camera also has its own opinion, and none of the other levels agree with it.

The best I'm able to do is levelish and squareish. Then I fix it in post.

OK. Than fixing the residual error in post seems to be quite common.

But does anyone know what kind of IC diameter should be expected for real from that lens? And what is the MTF according to that IC?
Any hands-on experience?

It's like using Canon EF glass on a Fujifilm GFX or Hasselblad X-camera. The diameter of acceptable lens quality depends on the digital back you're using, the aperture of the lens you're shooting, maybe the shooting distance and im some cases the subject (landscape vs. portrait). In case of very high resolution sensors it may also be an issue of sample variation.
Just as a general rule: By using only high grade glass blocks, putting more effort in manufacturing lens elements to smaller tolerances and assemble them with tighter tolerances you can lift an old optic design to a new performance level. It just gets more expensive.

 

[mristuccia]

A shot of the Shell-Haus coming out from today's shooting with @Whisp3r in Berlin.
Very cloudy day, I've decided to go with BW.


Cambo WRS-1600 | CFV-100c | SK 72L | Some vertical shift, around 10-15mm

 

[danlindberg]

Racing duck!

 

[miriquidi]

I'm still in ironing out mechanical bugs within the setup. Tamron 17-50 mm F2.8 at around 30 mm focal length and roughly F8. shifted about 2 mm down. ISO200, 1/320 s exposure time on Olympus E-PL5 as digital back. The experimental techcam is inbetween both. Handheld.

 

[miriquidi]

I have another question regarding technical cameras and wide angle lenses, as that with leveling the camera didn't really work with my 17 mm wide angle (34 mm equ.). Sorry for noob questions.

The image circle of a lens need to be quite large relative to the sensor, to be of any use for shifting. And when using the outer parts of that circle, distortion is getting more pronounced. (I've noticed it in a panorama. If leveled the camera and moved the camera behind the tripod fixed lens. The centre shot had no plunging lines, but the outer images for themself had no straight lines. )

I've done a small sketch to illustrate the problem. It's the distortion pattern (at close range) of an Samyang 14 mm F2.8 UMC from lenstip.com and in there I've sketched in the 4/3s sensor area. So even when leveling the camera, if I shift the camera down, that distortion will again create plunging lines. (Ignore the mustache in the picture below.) So to compensate for that, the arrangement has to be slightly tilted in order to approximately maintain straight lines, than shifted to compensate for the changed view and so on, right?

 

[John Leathwick]

A couple of images from a recent trip up onto the Craigieburn Range, inland Canterbury (NZ)...

A rotated panorama at 1800m elevation with GFX100s/F-Universalis/S-K Apo Digitar L-88, with a small amount of front tilt




Closeup of a cushion plant (Haastia recurva) growing in a rock crevice at 1850m - commonly known as vegetable sheep, this one is relatively open, with the individual shoots about 15mm across, and covered in a dense matt of hair for protection against the extreme climate - GFX 100s/F-Universalis/Zuiko OM Bellows Lens 135mm with 5 degrees front tilt and 15mm of rear rise - stack of 10 images.



-John

 

[rdeloe]

I have another question regarding technical cameras and wide angle lenses, as that with leveling the camera didn't really work with my 17 mm wide angle (34 mm equ.). Sorry for noob questions.

The image circle of a lens need to be quite large relative to the sensor, to be of any use for shifting. And when using the outer parts of that circle, distortion is getting more pronounced. (I've noticed it in a panorama. If leveled the camera and moved the camera behind the tripod fixed lens. The centre shot had no plunging lines, but the outer images for themself had no straight lines. )

I've done a small sketch to illustrate the problem. It's the distortion pattern (at close range) of an Samyang 14 mm F2.8 UMC from lenstip.com and in there I've sketched in the 4/3s sensor area. So even when leveling the camera, if I shift the camera down, that distortion will again create plunging lines. (Ignore the mustache in the picture below.) So to compensate for that, the arrangement has to be slightly tilted in order to approximately maintain straight lines, than shifted to compensate for the changed view and so on, right?
View attachment 225291

In the spirit of keeping this thread focused on Technical Camera Images, can you start a new thread called "Distortion" and re-post your request there? @darr 's answer is great and should follow. Then we can delete these three posts from here so we can carry on in the new thread. I have a nice example that illustrates what you're asking about -- but I want to put it where it belongs (in that new thread).

 

[miriquidi]

Good suggestion. Thread is open.

 

[danlindberg]

Öresundsbron. The impressive bridge connecting Malmoe to Copenhagen. 16 km long diveded to the bridge, an artificial island and a tunnel under the sea. Shot with a 3 minute exposure at dusk. The idea was a second long exposure (to the right of this image and make it a large pano, but the light changed so much in such a short time I struggled with the stitch and gave up. Instead I simply cropped the original to a 2:1 and thanks to 100mp back I still have 1 metre long uninterpolated file.

 

[John Leathwick]

Three more close up images of scree plants from my weekend mountain trip. We were fortunate in having permission to use the ski road, so I took my two Zuiko OM bellows lenses for which I've made a custom OM-mount board. I really like the rendering of these older lenses, particularly their smooth OOF zones. All three are focus stacks, manually operated with my GFX 100s/F-Universalis. The first two with the 80mm are of plants around 5 cm high, so at an effective taking scale of around 0.x5, while the third is taken with the 135mm at a taking scale of around 0.2x. The last two images both used front tilt of around 7 degrees, the maximum available with the F-Universalis inverted to get down to ground level. All three were stacked in Zerene Stacker.

-John