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10-30-2017, 05:36 PM   #46
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QuoteOriginally posted by pendennis Quote
Zeiss first coated lens elements in 1935, and Kodak didn't start to coat lenses until ca. 1938. However, as early as the 1890's experiments started to take place for coating lenses.
This was for optics designed for military applications, single coating started to appear in the consumer market until the late 1940s when 35mm photography was in its early stages. Multi coating started to appear in 1950s along with the first retro-focus wide angle lenses for SLRS.

QuoteOriginally posted by TomB_tx Quote
Leica users forum where a user compares picture results from an early 1926 Leica model A (the first successful 35mm still camera) and its original Elmar 50 mm f3.5 uncoated lens, using Portra 160 film, to a Leica M10 (24mp) camera with modern lens.
The Leica Elmar 5cm f/3.5 is a very simple optical design, the fact that there isn't much difference between the coated/uncoated versions isn't hugely surprising. Lower element count means fewer air/glass interfaces where internal reflections can propogate and foul up image contrast. Older uncoated/single coated lenses with apertures of f/2.8 and faster show a more dramatic change in imaging characteristics.

10-30-2017, 05:56 PM   #47
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QuoteOriginally posted by Digitalis Quote
The Leica Elmar 5cm f/3.5 is a very simple optical design, the fact that there isn't much difference between the coated/uncoated versions isn't hugely surprising. Lower element count means fewer air/glass interfaces where internal reflections can propogate and foul up image contrast. Older uncoated/single coated lenses with apertures of f/2.8 and faster show a more dramatic change in imaging characteristics.
That's really the great advantage to the tessar design, isn't it? Works great coated or not, and is very sharp either way.
10-30-2017, 06:40 PM   #48
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QuoteOriginally posted by timw4mail Quote
That's really the great advantage to the tessar design, isn't it?
Unfortunately it isn't that fast or well corrected, the Kodak Ektar 50mm f/1.9 from 1941 even with its triplet of cemented groups, desperately needed coatings in order to produce reasonable contrast at its widest aperture.

The need for faster lenses pushed the industry towards improved multi-coatings. Sticking with the design philosophies of the past simply didn't cut it for 35mm photography. The lenses we work with today would have been inconceivable in the 1950s.
10-30-2017, 07:51 PM   #49
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What struck me the most about this comparison was the muddy, artificial look of the digital colors, particularly on the overall view, but also on the crops. I normally prefer 35mm film and a three element, multicoated lens to any digital cameras, so resolution doesn't mean much to me. Mainly the colors, DR, and the rendering of space.

10-30-2017, 08:21 PM   #50
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QuoteOriginally posted by stevebrot Quote
First off, I want to tell you how much I respect the huge library of photo-associated visuals you have generated and share with the users on this site. I hope you don't take any of the below as criticism.

What I am unable to do is infer how much detail was captured on the negative itself. To estimate that I would need the pixel efficiency of the system (optics, image processor, presentation, etc.) so I would have a notion of how much was not "seen". The D800 is a good example in that its rank should have been above the scanner for a 1x full-frame copy based on capture resolution alone. Was there a focus problem? Optical field curvature? Loss due to Bayer interpolation? I dunno.

To be honest, I would not expect any of the systems to fully replicate even a Kodak Gold 200 negative. There is always sampling loss. The same is true for an optical enlargement, a projected image, a contact print, or even direct microscopy.

FWIW, it would have interesting to see if the D800 and the K20D were equivalent at 1x (similar pixel pitch).
Steve, I am always happy to share and learn just like everyone. Even though I make sure I have my facts straight, I am always willing to listen to anything constructive.

First I shot a series on Techpan and scrutinized with my 50X microscope the best of the lot. I then used the same frame for scanning/copying.

I rented a D800 and tested to see if I can attain the same results as DPREVIEW of Nikon D800 using my Nikon 55mm F2.8 macro. Since I matched what they showed, I know everything is up to snuff. I then used the D800+Nikon 55mm F2.8 macro+PB-4+PS-4 autobellows to copy the full frame of Kodak Techpan. I tried numerous apertures and micro focusing adjustments to attain the best results I could get. Given that DPREVIEW attained about a 36 1 in their test and I attained (8 X 4) 32 1/5 - from a copy on film vs the original test target, that seems right. That it can attain this relatively high mark means the source (test target on Techpan) had to contain more detail.

Using my Pentax K20D+50mm f4 macro+autobellows+slidecopier, I optically magnified the center portion of interest about 4.5X to show that indeed the frame of Techpan had in fact more unresolved detail at (11.5 X 4) 46 1 then the Nikon D800 at 32 1/5.

I am very interested in trying the D850 and not just for the 45MP sensor but also to see how the built-in negative copy conversion works.
10-30-2017, 10:45 PM   #51
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QuoteOriginally posted by LesDMess Quote
Steve, I am always happy to share and learn just like everyone. Even though I make sure I have my facts straight, I am always willing to listen to anything constructive.
Me too

I read this last message and with some time on the DPReview for the D800, I am more clear on your methods and they are close to what I thought you were doing though with a few wrinkles. If I am reading the D800 review correctly, they measured 3200 lph which translates to 133 l/mm vertical for that camera with the Nikkor AF-S 50/1.4 G framed to the 3:2 region of an extended ISO 122233 chart. That is a pixel efficiency of 69% and at 1x magnification would badly underestimate the Tech Pan performance if it approaches or exceeds that of the D800.

This is a bit of a rabbit hole and I don't want to hijack the thread more than already done. I would like to continue further via private message if that is OK. I have some additional questions and an observation or two.


Steve

Last edited by stevebrot; 10-30-2017 at 10:51 PM.
11-01-2017, 08:42 PM   #52
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QuoteOriginally posted by stevebrot Quote
For those wishing to checkout the published MTF graphs for Technical Pan, the package insert is available for download from the "Wayback Machine".

Wayback Machine: Kodak Technical Publication P-255

Processing in Technidol yielded MTF-50* of 100 cycles/mm which approximates 100 lp/mm. PF member Nesster has a Modern Photography article from the mid-1980s on his Flickr photostream where attempts were made to extract 100 lp/mm from lenses (all fast-50s) and films available at that time. IIRC, that number proved illusive. I will see if I can find it and post it here if I do.

Addendum: Certain current emulsions claim much higher resolution than what was available from Technical Pan.

More Addendum: By calculation, the K-1 can only extract about 102 lp/mm maximum based on horizontal pixel pitch alone. Actual will be somewhat less.


Steve

* One can get much higher numbers at higher contrast, but those are not applicable for typical pictoral use.


I still have one roll 135 Technical Pan and a box of 50 4X5 sheets, plus lots of its developer
11-15-2017, 02:57 AM   #53
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Pentax P3, D-FA 24-70 F2.8, Fuji Neopan Across 100. The camera was in P mode.

So this is a 51mp scan of a negative. Unprocessed, no cropping. Done using a drum scanner. I am not trying to say that this scan shows superiority of film. I just want to contribute to discussion by providing some real-life examples.

More examples in this thread.

11-15-2017, 04:31 PM   #54
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I would like to note that acros is not the best representative of film, it's tonality is very similar to digital's, unlike most BW films. I like this scan better too.. 01 | Kaunas. Fuji Neopan 100 Acros. Pentax D-FA 24-70 F2.8. | Flickr
11-15-2017, 06:18 PM   #55
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Hello

My intension of the original question was the film has for physical quality and not what the best possible scanner on the market can do with it?

I mean something like the the number of particals which can be identify with microscope? Or something like that. A fullformat Kadochrome 25 should then be compared by a 70-150Mp digital picture?
11-15-2017, 08:21 PM   #56
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The technologies are too different to compare them in similar terms, imo. Film is way better, digital looks like crap, also imo. It's not about resolution, but contrast/tonality and color.

'As expected, the film camera appears to capture slightly more detail than the digital camera. Perhaps a higher resolution scan would yield even more detail, although I think this is reasonably close to this film's limit. However, as expected, the film image looks extremely grainy. From my perspective, I prefer the digital image. Even in a 4x6 print, the film grain is visible, while the digital image looks fantastically smooth. An 8x10 print is still small enough that the theoretical resolution advantage of film is invisible, but large enough that the film grain is clearly apparent (to my eyes). As the print size increases, the graininess of the film becomes objectionable long before its technical resolution advantage becomes visible.

Of course, this is subjective, and different people will reach different conclusions. However, it is definitely worth seeing some prints made from digital images before concluding that they can't be as good as film-based prints based on resolution numbers alone. Nonetheless, if you don't mind the grain and want the most resolution possible, it still looks like film has the edge.'

Film vs. Digital

Last edited by Ranchu; 11-15-2017 at 10:40 PM.
11-15-2017, 10:37 PM   #57
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You could also look at this, it has some shots with a microscope.

Large Format Camera Comparison | On Landscape

The IQ180 is a 80mpx full frame medium format digital back, so you can compare it fairly evenly with the Mamiya 7 shots.
Attached Images
 

Last edited by Ranchu; 11-15-2017 at 11:06 PM.
11-16-2017, 12:16 AM   #58
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QuoteOriginally posted by Ranchu Quote
As expected, the film camera appears to capture slightly more detail than the digital camera.
Yeah, it does seem to be very subjective, especially using the images on that page you linked to. In some of the examples the digital looks better to me, in some the film. But also, that was a 6 MP camera image and 200-speed film...
11-16-2017, 12:37 AM   #59
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I mainly linked that page to illustrate how different a film image and a digital image were.

Also, this below is about the page where you can slide the comparison back and forth...

'The one issue with taking images of long distance views is that any difference in focal lengths can't be compensated for by 'just getting a little closer' so we can't use these results as a resolution comparison without taking into account the slight differences in focal length. These differences can be summarised as a 7% advantage for 4x5 and 8x10 over the IQ180, a 20% disadvantage for the Mamiya 7 and a 20% advantage for the Sony A900. In real terms, the 7% advantage for the 4x5 and 8x10 is small enough to be difficult to notice (effectively this is smaller than a 1/10 of a pixel advantage in fine detail) and is equivalent to the difference between 18Mp and 21Mp cameras. The 20% disadvantage for the Mamiya is fairly large and would be noticeable and represents the difference between 10Mp and a 16Mp camera'

Last edited by Ranchu; 11-16-2017 at 12:42 AM.
11-16-2017, 03:48 AM   #60
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So another thing. Assuming the Mamiya 7/Portra resolution is the same as the IQ180 (53.7mm 40.4mm), 80mpx, 35mm/Portra (24mmx36mm) should be 31.8 mpx. That and DR you can take a bath in..

Last edited by Ranchu; 11-16-2017 at 04:19 AM.
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