lens for digital stitching - digitars or apo symmars / SS HM

[daz7]

Guys, what lens in your opinion would give me better image quality across the whole frame on the 3x3inch digital stitch and 6x9 film - digitar 120mm N or apo symmar 120 / super symmar HM120?
I know that digitar looks much better on digital backs with no stitching or movements and it's sharpness is superior in the middle of the image circle. However, the closer I would get to 110mm radius, the worse it woud get probably, while for analog lense 110mm circle sits in its centre, still.
Anyone have experience shooting both Digitars and Apo symmar 120/ super symmar 120?

 

[Alkibiades]

apo digitar 120mm N and apo symmar 120 mm have the same lensdesign. the results will be more or less the same.
also the physical image circle is the same, however by the digital version the image circle of 110 mm is the image circle of very good usable quality at aperture 8-11. when closed to 22 the image circle is bigger and enough for 4x5 inch. You can use always more of the iage circle with film than with digital use. super symmar hm is a great lenses for film but nonsence for digital use. You can never use this big image cirlce with digital technic.

 

[daz7]

Thanks a lot for answering my question.

I did not realize that apo symmars and digitars are exactly same lenses. From what I read, people usually are much happier with digitars than with apo symmars.
Are these lenses really exactly same, or just similar?

Also, with Super Symmar HM 120, from what I can see, its image circle ranges from 180mm at f5.6 up to 211mm at f22, wich is only 10 or 20mm more than Apo Symmar L or Digitar Aspheric, so not that extreme. Unless I read that wrong.

 

[Alkibiades]

Thanks a lot for answering my question.

I did not realize that apo symmars and digitars are exactly same lenses. From what I read, people usually are much happier with digitars than with apo symmars.
Are these lenses really exactly same, or just similar?

Also, with Super Symmar HM 120, from what I can see, its image circle ranges from 180mm at f5.6 up to 211mm at f22, wich is only 10 or 20mm more than Apo Symmar L or Digitar Aspheric, so not that extreme. Unless I read that wrong.

Apo digitars and apo symmars are not the same lenses!
please read what i was written exactly.
Only The Apo Digitar N 5,6-120 mm is nothing more than the Apo Symmar 72° 5,6-120 mm. Yes, thay are physicly the same lenses.
but only these.
Apo Digitar lenses are all different and based on different lens designs. Apo Digitar means only that there are lenses for digital use.
Older schneider names were different and meaned the lens design like Angulon, Componon, Symmar, Xenar....
This is not the case with the name Apo Digitar.
And forget the image circle of the analoge lenses when you want to use them with digital stuff.
The image circle means nothing with digital use.
the important thing is not the physical image circle of the lens- (all analoge 4x5 lenses has much too large image circle for digital sensors)
but the question of real usable image circle for digital use with modern sensors.
For analoge 4x5 photography the bigger image circle and image angle was an advantage: more movements.
So stanadart Symmar-S was 70°, Apo Symmar 72°, Apo symmar L 75° and the Super Symmar HM 80°, and the latest Super Symmar XL was at last 105°.
But the biggest digital sensor is smaller than 4,5x6 cm Film format, and 4x5 film are 10x13 cm. look the difference.
So the Symmar-S with 70 ° design with (let me explain it ease) concentrated resolution power is much more suitable for the little digital sensors than the big stuff with extremly large image circle. And Schneider did this for they digital lenses: they took the older lens designs with smaller image circle and tranform them with new technology and new glasses to the digital time.
This is maybe confused but logic.

 

[daz7]

Thanks for your explanation.
I can agree that digital sensors due to their small area, use only very small portion of the lens' image circle, so for a single shot or even a two image stitch most analog lenses provide too large of the image circle compared to their resolution at the centre, so the digitars are much better suited and the small image circle is almost never an issue.

However, I have just finished building my own motorized attachment to move the back in up to 6 sequential positions (2 rows, 3 columns) automatically and firing a shot in each spot. That would cover the area very close to 8x9cm film after stitching. For this application I would require an image circle of around 120mm (or 110mm if I crop it down to 6x9)
With roughly 15-20mm movements margin, I would then require a lens with at least 150mm image circle, or optimally 180mm.
That's the reason I am considering SS HM 120 -I would be using 80% of its image circle.

 

[Alkibiades]

Thanks for your explanation.
I can agree that digital sensors due to their small area, use only very small portion of the lens' image circle, so for a single shot or even a two image stitch most analog lenses provide too large of the image circle compared to their resolution at the centre, so the digitars are much better suited and the small image circle is almost never an issue.

However, I have just finished building my own motorized attachment to move the back in up to 6 sequential positions (2 rows, 3 columns) automatically and firing a shot in each spot. That would cover the area very close to 8x9cm film after stitching. For this application I would require an image circle of around 120mm (or 110mm if I crop it down to 6x9)
With roughly 15-20mm movements margin, I would then require a lens with at least 150mm image circle, or optimally 180mm.
That's the reason I am considering SS HM 120 -I would be using 80% of its image circle.

all of these 120 mm have image circle even at 5,6 bigger than 155 mm, they all cover full 4x5 wide open.
for working aperture 11 would be the best standart.

 

[rdeloe]

Only The Apo Digitar N 5,6-120 mm is nothing more than the Apo Symmar 72° 5,6-120 mm. Yes, thay are physicly the same lenses.
but only these.
Apo Digitar lenses are all different and based on different lens designs. Apo Digitar means only that there are lenses for digital use.
Older schneider names were different and meaned the lens design like Angulon, Componon, Symmar, Xenar....
This is not the case with the name Apo Digitar.

I've always found it interesting that the basic lens parameters and block diagrams for the Schneider-Kreuznach Apo-Digitar 80mm f/4 and the Componon-S 80mm f/4 are absolutely identical. That's an amazing coincidence if the Apo-Digitar is a different lens design made specifically for digital.

There are two more amazing coincidences like this. The Apo-Digitar 90mm f/4.5 has exactly the same basic lens parameters and block diagram as the Apo-Componon HM 90mm f/4.5 (enlarger variant); later versions for industrial uses, like my Type -0024, are slightly adjusted for different magnifications common in industrial line scanning settings (but are still basically the same lens design). The Apo-Digitar 60mm f/4 and the Apo-Componon HM 60mm f/4 are also almost exactly the same. The only value that differs is SF'=40.8 for Apo-Digitar and 40.9 for Apo-Componon.

 

[Alkibiades]

I've always found it interesting that the basic lens parameters and block diagrams for the Schneider-Kreuznach Apo-Digitar 80mm f/4 and the Componon-S 80mm f/4 are absolutely identical. That's an amazing coincidence if the Apo-Digitar is a different lens design made specifically for digital.

There are two more amazing coincidences like this. The Apo-Digitar 90mm f/4.5 has exactly the same basic lens parameters and block diagram as the Apo-Componon HM 90mm f/4.5 (enlarger variant); later versions for industrial uses, like my Type -0024, are slightly adjusted for different magnifications common in industrial line scanning settings (but are still basically the same lens design). The Apo-Digitar 60mm f/4 and the Apo-Componon HM 60mm f/4 are also almost exactly the same. The only value that differs is SF'=40.8 for Apo-Digitar and 40.9 for Apo-Componon.

View attachment 187448

Yes, the componon, componon-hm, symmar-s and macro-symmars design are used in the apo digitars... smaller image angle is better for digital use than modern analoge designs with extra large image angle..

 

[daz7]

I just checked graphs and lens data from Schneider website for apo-symmar 120mm and apo digitar 120mm N and it seems that these are two different lenses.
However, it seems that Apo-Digitar 120 N and Apo-Componon HM 5.6/120 may be the same lens as the internal dimensions are exactly the same.

 

[rdeloe]

I just checked graphs and lens data from Schneider website for apo-symmar 120mm and apo digitar 120mm N and it seems that these are two different lenses.
However, it seems that Apo-Digitar 120 N and Apo-Componon HM 5.6/120 may be the same lens as the internal dimensions are exactly the same.

Another coincidence! In seriousness, I have noted the same thing when I compared lens block diagrams and basic lens characteristic data -- identical.

 

[Alkibiades]

I just checked graphs and lens data from Schneider website for apo-symmar 120mm and apo digitar 120mm N and it seems that these are two different lenses.
However, it seems that Apo-Digitar 120 N and Apo-Componon HM 5.6/120 may be the same lens as the internal dimensions are exactly the same.

all these 3 lenses have the same 6 elements lensdesign,
whe there is a difference- maybe not- than only that the componon would be more calibrated for near distance and the apo symmar and apo digitar n for infinity.
The information that the 120 apo symmar and apo digitar n 120 mm are the same lenses I get from schneider directly.
in the begining of my digital-middleformat story I get a apo digitar 120 n in a old schneider shutter iris. I wanted to put the glasses in a copal shutter and was surprised when I puted the glasses out of the shutter becouse the name apo symmar was written on it. I spoke than with the schneider-lens-god and get the information that both lenses are the same and at the biginning thay even dont chnge the name on the barells but only on the shutter- the barells were full inside the shutter and invisible from outside.
later I also had a leate apo digital n and i tested them both-no difference,
I have a lot of lenses, so for examle the componon 100 mm and symmar-s 100 are the same lenses also but only symmar with mc couting ...
anyway with all these lenses you will get great results for less monay.

 

[rdeloe]

A lot of the knowledge about the design history of these lenses is probably lost forever. Even people still at Schneider don't necessarily remember because the people involved in early design decisions from the transition to digital are retired or dead; what they knew might have been lost since the 1982 bankruptcy and reorganization.

To illustrate, I bought an Apo-Componon HM 90/4.5 in the Makro-Iris mount, with the rear cell labelled Type -0024. Schneider made and sold many versions of the Apo-Componon HM 90/4.5 (enlarger, Digitar, and various line scanning lenses in Makro-Iris mounts). I wanted to know the properties of mine, specifically the optimum magnification. Nothing was ever published on Schneider's website about Type -0024 lenses (as far as I could figure out with a lot of searching using the Internet Archive). A friend of mine with good connections in the North American division finally was able to get the USA Schneider people to get the information from the German Schneider people. It turns out that it was a mistake! The lens cells labelled Type -0024 are actually mis-labelled Type -0025 cells (for which PDFs can still be found).

Curiosity aside, Schneider-Kreuznach made some phenomenal lenses. My Apo-Componon HM 90/4.5 is superb from close up to infinity, with movements, on my GFX 50R. I use it with my VX23D + GFX 50R as a tilt-shift lens, and with a focusing helical on my GFX 50R as a compact and lightweight "walking around" lens. It pairs up nicely with the even tinier yet still superb Apo-Componon HM 60/4.

 

[daz7]

Thank you guys for your input - really valuable!
After browsing all old Schneider data, Im now leaning towards 150mm Digitar - its MTF looks much better than mtfs of 120N and its illumination uniformity at larger area is much better than both 120N and 120asph.
Also, 150N seems to be a different lens from componons HM and apo symmars - looks as if Schneider tweaked their componon HM150 by a few milimiters to come up wth the 150N specifically for digital use.

I would stil prefer 120mm perspective flexibility when stitching but on the other hand, 150mm may not be far off with a bit more stitching.
I think I will now start a hunt for a good copy of 150N.

 

[Alkibiades]

the Apo Digitar N 150 mm is indeed a very nice lens, I had two of them but I sold them, I do not much with longer lenses.
This lens is also very expensive now- You should also take a look on similar Rodenstock lenses: Apo Sironar digital 135 and 150 mm will deliver you same image quality as the 150 n but are much cheaper, becouse more available.

 

[daz7]

I will resurect my old thread - I just though that someone facing similar dilemma may be interested - I recently bought an unused (!), old stock Super Symmar HM 120mm - I just could not resist having this 40 years old beauty. Some time ago I also managed to get a hold on SK150mm Digitar in addition to my old 135mm Rodenstock digital and finally, last week got a 120mm digitar aspheric as a short loaner from a friend.
I did a quick test using old backs suitable for large stitches - 33mp and 48mp Sinar evolution backs (Dalsa). Why such old sensors? Well, they do not suffer with a lot of color cast when applying movements or using full image circles (only 48mp Dalsa gives a slight but rather correctable cast)

I've tested all backs with a single shot and then for maximum stitches covering around 8cm x 10cm area with the sensor on Sinar P2/P3 (that's 150-220 megapixels and around 130mm image circle used). I've tested all lenses within my typical workig aperture of f11 for digital lenses and f16 for SSHM.

The best ones in the centre of the single shot with no stitching were: 150SK (which I love already), then 135 rodie and 120mm aspheric with almost no visible differences, and finally 120HM very, very slightly behind, in this order, however the differences were really miniscule and could be down to the operator's error. Overall all lenses were great and I could recommend any of the above. All of the lenses were beautifully sharp and the differences were mostly up to very slight changes to contrast, colour rendition, bokeh and microcontrast. Gerenally, the differences were much, much less prominent than I would expect. Quite possibly the outcome would be different on large megapixels backs but I do not have a 150mp back to check, unfortunately.

The best lens for large stitches turned out to be SS120HM and that surprised me a bit - there was no visible losss in sharpness in corners, no color cast, no need for center filters. The second one came Rodie135 and 150SK again very very close (150SK a little bit better within around 100mm circle and rodie sligthly better in corners), and the last one 120mm aspheric (great in the centre but dissapointing and a bit 'mushy' in extreme corners). Again, the differences between the lenses were quite small, but SS120HM gave me truly outstanding results, especially on the 33mp dalsa sensor.
Also, SS120HM had the best bokeh of all the lenses and I absolutely love its nicely balanced colour rendering.

Overall, I am extremely happy with the Super Symmar HM i got - there may be some sample-to-sample variance between these analog lenses due to different manufacturing processes used 40 years ago but it seems that I was lucky with my specimen. I will definitely keep it. What a gem!

 

[Alkibiades]

Your results did not surprised me, I did tested even a lot of more lenses in this range.
The Super Symmar HM war Schneider high end line, using special glasses ( also the Macro Symmar HM, that was relabeled to Apo Digitar M)- that was the answer on rodenstock Apo Sironar W -line. It would be much more interesting, when you would use on all lenses the same aperture 11. Also Symmar HM.
By doint that the results should be even closer- the symmar HM should be also sharper with 11 that 16. You dont need the whole image circle of the HM lens, that would even cover 5x7 inch format, what is not interesting for digital.
I like also the fact that differance from roddy 135 to the hyped 120 aspheric is more or less not visible. funny, that the one is now 4 times more expensive that the other on second marked. Thanks a lot for sharing your experiences!

 

[Paul Spinnler]

Hi Daz

I cannot speak for the old sensors, but I think you may not see the differences, which do exist, between say a 120 ASPH and a HM with a 40 megapixel back.

In my experience, and I use the 120 ASPH on a 150 megapixel back on the Alpa Pano, the resolution is excellent. I have also a lot of analogue lenses which I can use via my Arca Swiss F metric with digi adapter, but only a few are really up to the task to resolve the small pixel pitch of the latest sensors.

It is true that the old lenses have enormous ICs, but usually that comes with the trade-off of lower sharpness which I think you can not see with fat pixel backs. So for your use case the 120 HM is perfect, but someone with a 150 megapixel back may in the end extract more with the 120 ASPH.

For example, I found that everything below 65mm was not that good and above that it was hit and miss. I was positively surprised by the 65mm Grandagon for example.

I think the 120 ASPH is a spectacular lens and I think especially with 150 megapixels you see what you get ... it is tack sharp with very fine micro-details, even on my achromatic back.

It is one thing to resolve well on a 15 year old back and another one on a current one and the price of the 120 ASPH is not random ...

 

[4x5Australian]

I tested my near-pristine condition copy of the SK Super-Symmar HM 120mm with my IQ4-150, using my Arca-Swiss Rm3di.

The targets were flat building facades at a variety of distances, in direct sunlight. I deliberately looked for situations in which I could test the lens with 20 to 25mm of rear fall, to replicate a situation I encounter often in my architectural photography. I aligned the camera perpendicular to the facades by carefully matching horizontal features to the IQ4 live view grid at 100%. Frames were taken at zero lateral shift and when shifted to 15mm. The aperture was f/11.

When viewed in Capture 1 at 100% or 50%, the images lack the sharpness of textural details that I am accustomed to seeing from my newer digital-era Schneider lenses. When viewed at 25%, the images looked quite OK.

I am currently testing a number of film-era longer focal length lenses and expect to be able to report some successes when finished.

 

[Paul Spinnler]

I think the Sironar-S lenses might be quite good from 135mm upwards. I actually have a 360, but never used it with the digi back. Might also have to look at this.

 

[anyone]

I think the Sironar-S lenses might be quite good from 135mm upwards. I actually have a 360, but never used it with the digi back. Might also have to look at this.

I have the 135,150,180,210 and can confirm that they work well with my IQ160.