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Thread: Resolution Comparison Between Films?

  1. #31
    Drew Wiley
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    Re: Resolution Comparison Between Films?

    You're guessing. I've seen color shots from 20, 30, 40, even 50 years ago that would be difficult or impossible to match with any kind of consumer color film or camera equipment today, things you wouldn't even believe if I told you. And I have no idea what is actually possible now, though am aware of certain exotic technologies behind them. I just know that you aren't even remotely on the right track, Pere. You're still thinking on WWII terms. Just get ahold of a CIA, NSA, or NASA credit card without a spending limit, and I'll tell you where you can go camera shopping. They'll explain the rest, if you don't get arrested and interrogated first. But if you want a set of clues, think about how advanced hybrid medical microscopes work at one extreme, separating and then precisely recombining specific wavelengths of light with magnetically controlled mirrors, and the latest computer-controlled super-observatories at the other extreme, with their highly advanced hybrid optics, and design something in the middle. You could open your own internet spy supply company during this covid crisis.

  2. #32

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    Re: Resolution Comparison Between Films?

    Pere, those resolutions you are throwing around are lines/mm, not line pairs/mm or cyc/mm - halve them if you want to compare with more regular films. Then look at how badly those Aerochromes (and Aerocolor) really perform. They were largely for mapping or specific camouflage detection etc - if you want to waste hours of time, you can look up the rectifying enlargers made by Wild, Zeiss etc. The BW films were and are for high res recon. 5.5" rollfilm tended to be used for recon, 9.5" for mapping, though the satellite missions apparently used 9.5" on super thin bases. And 3409 is nowhere near the highest resolving disclosed aerial film Kodak made - amongst others there was SO-209 with a disclosed Resolving Power of 1160 lines/mm (580 lp/mm) on a 1.5mil (38 microns) ESTAR base - by the looks of it, designed for a diffraction limited f2.8 optical system. The problem with all of these films is that they were not designed for pleasing pictorial purposes but for specific military/ industrial purposes that required the ability to image an object of a specified diameter from a specified altitude. A look at 3409's spec sheet will show very clearly that it is designed for high contrast resolution alone - over sharpness or low granularity, both of which matter a lot more in regular photography at ground level.

    Drew, I think you mean the NRO? And FLIR, amongst others, are industry standard manufacturers of high res aerial imaging kit these days - at least the civilian accessible stuff.

  3. #33

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    Re: Resolution Comparison Between Films?

    Quote Originally Posted by interneg View Post
    Pere, those resolutions you are throwing around are lines/mm, not line pairs/mm or cyc/mm - halve them if you want to compare with more regular films. Then look at how badly those Aerochromes (and Aerocolor) really perform. They were largely for mapping or specific camouflage detection etc - if you want to waste hours of time, you can look up the rectifying enlargers made by Wild, Zeiss etc. The BW films were and are for high res recon. 5.5" rollfilm tended to be used for recon, 9.5" for mapping, though the satellite missions apparently used 9.5" on super thin bases. And 3409 is nowhere near the highest resolving disclosed aerial film Kodak made - amongst others there was SO-209 with a disclosed Resolving Power of 1160 lines/mm (580 lp/mm) on a 1.5mil (38 microns) ESTAR base - by the looks of it, designed for a diffraction limited f2.8 optical system. The problem with all of these films is that they were not designed for pleasing pictorial purposes but for specific military/ industrial purposes that required the ability to image an object of a specified diameter from a specified altitude. A look at 3409's spec sheet will show very clearly that it is designed for high contrast resolution alone - over sharpness or low granularity, both of which matter a lot more in regular photography at ground level.
    Yes, you are right... I missread the l/mm

  4. #34
    Drew Wiley
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    Re: Resolution Comparison Between Films?

    No Interneg, nobody like you're referring to. I'm speaking of people often working from multi-billion dollar purchase orders, either classified or multi-national, as in huge international observatories, which now involve many synchronized giant flexible mirrors, though they are capable of prototyping just about anything for anyone at the right price. And I am only aware of how certain segments of surveillance were done up to about 20 yrs ago, one of which involved truly state of the art 10X10 color enlargers (which I've personally seen the inner guts of, though not whole machines) for very precise large true color images readily understood by decision makers, in contrast to satellite imagery, in a classified facility where absolutely no digital technology was allowed, lest there would be any doctored-up Photoshoppish claims (alas, we have a history of starting wars based on sheer cartoons, dubious xerox sheets, and mere rumors; but those were predetermined and not objective decisions). I've seen prints of shots taken with shipboard cameras probably nobody on a forum like this would even believe possible, and don't want to talk about for other reasons (people like me aren't even supposed to see those pictures). And I've interacted with extreme custom optics manufacturers in this area as a supplier of incidental supplies, including those who made the Hubble correction lenses. So I can sorta put two and two together at times, but am not an optical engineer myself, and can hardly imagine what is possible to do now because it factors in all kinds of potential hybrid options which began defying the limits of conventional lens design a couple of decades back. I'm also aware of several other clandestine inventions that would sound awfully sci-fi, but so did landing on the moon at one time. This area is a hub for that kind of innovation - military applications are nearly as big as consumer electronics R&D, but bit by bit, things slips out. That's why every single aspect of tech around here attracts industrial spies like moths to a lightbulb.
    I'd be happy just to find an affordable old Zeiss microscope and look at tiny critters in a drop of water with my own eyes once again.

  5. #35

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    Re: Resolution Comparison Between Films?

    Drew - if those enlargers were on Durst chassis, whoever was telling you about those enlargers was pretty likely being a bit economical with the actualité of their use. HK, Fotar, De Vere Apollo/ Vulcan chassis would be more believable, but most of them already came with excellent light sources for the purpose - and they had rollfilm and on-baseboard vacuum easel capabilities that dwarf anything Durst or the guy in Oregon ever seem to have come up with. Was Jens Jensen the source of the 'no digital allowed facility' story?

  6. #36
    Drew Wiley
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    Re: Resolution Comparison Between Films?

    You're still in the toy realm, Interneg. So am I, and I built a custom color enlarger myself that dwarfs my Durst L184 color unit. I'll just leave it where I left it. I've seen the guts of the colorhead with my own eyes and handled em. I was researching my own design and wanted to detour the horrible heat and maintenance issues of big Durst and smaller ZBE units. That was in Cibachrome days when very bright colorheads were required, and I already had a Durst mural colorhead, and it doubled my utility bill. I never learned who built their chassis. There were six of them, at an initial cost of about 200K apiece. The colorheads were all true RGB additive for sake of optimal color accuracy (it does make a difference), and were one of the last R&D projects of Durst commercial division just before it shut down. Those heads were never marketed to anyone except whoever built the enlargers for the NSA. Designing a high-output simultaneous-additive enlarger is no easy task, believe me. You can't fake it. Fotar, DeVere, etc, never made anything like that. A few relative toys suitable for small fast RA4 prints have been marketed over the years, and big SEQUENTIAL additive pulsed-xenon heads were once made for the printing industy. As far as Jens goes, he was a chronic liar, but also a superb machinist, whether one could stomach his slippery business model or not. And he made most of his money on mandatory service contracts to big labs, rather than on the equipment itself. I have a friend who purchased well over a million dollars of gear from Jens, and for that kind of money, Jens actually delivered what he promised. Chris Burkett also got all his gear from him. He stiffed me, but then, as poetic justice, I was offered all those enlargers he sold to my friend for free upon retirement from that aspect of his lab. I just didn't have any more space for more 8x10 units except for one; but heck, even that one enlarger left me 20K ahead. Jens owed me some film punch components to supplement my original Condit gear. But Jens never built the NSA enlargers back east, nor was he ever equipped to make those kind of highly specialized filter components, any more than he could have fabricated a few especially rare Apo El Nikkor enlarging lenses he got ahold of to sell. He would have gone broke just trying, and with no conceivable market. They had to be changed out as a compete integrated set. He just happened to buy a lot of Durst commercial division leftovers as a big lot deal. And again, I can't go into detail, but I've been at a number of dinner parties attended by ex-spooks from these agencies and think tanks, and already knew about the kinds of very sophisticated cross-checks in place, whether the political policy makers take advantage of that kind of expertise and safety valve or not (often they don't, but then pin the blame on someone else when something goes terribly wrong). I was simply designing something one-off for myself, and was a bit too early to take advantage of computerized sine-wave control, but glad I didn't buy into it because the software and computer gear involved goes obsolete so fast. ZBE helped me with some of the electronic feedback brains because they had done the same for those classified units, so one more distinct confirmation. They weren't coordinated with Jens in any manner. All he knew about was switching out filters. I just have to deal with popping light bulbs, schizophrenic triacs, and a block and tackle system to service my own huge heavy colorhead - but it does cool efficiently. And to synchronize the two independently cooled hemispheres, I had to employ a joint monitoring system, which ZBE had already developed. Otherwise, I never could have afforded one. That could just have been done via routine printing tests and a color densitometer at the NSA; but the high heat of the enclosed Durst heads, which were never designed in the first place for the significantly higher density of additive filters, blistered out the dichroic filter sets within every six months and would have made precise synchronization unpredictable without internal feedback. Again, confirmed not only by own previous experience with high-wattage Durst, but by three different sources with little in common other than a specific end user, and certainly no admiration for one another in the case of Jens vs ZBE. Darn expensive rigs to maintain. I have no idea whether those things are still in operation or not. Even Jens couldn't make this kind of stuff up; too much of it not only makes sense, but lies behind my own working design either by inclusion or deliberate exclusion. I garnered clues wherever I could get them, that's all, and then took my own direction.
    Last edited by Drew Wiley; 18-May-2020 at 19:37.

  7. #37

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    Re: Resolution Comparison Between Films?

    Uber film resolution alone is only one potential facet of an expressive image.
    Consider the expressive abilities of prints made using sorta-focus or Soft-Focus lenses.


    Bernice

  8. #38

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    Re: Resolution Comparison Between Films?

    Quote Originally Posted by Drew Wiley View Post
    I've seen color shots from 20, 30, 40, even 50 years ago that would be difficult or impossible to match with any kind of consumer color film or camera equipment today,
    Are you sure that those were not 3 BW shots with color filters? Are you were guessing that it was 300lp/mm color film?


    Quote Originally Posted by Drew Wiley View Post
    You're guessing.
    No guess, in the military (SF) Color and BW orthophotomaps where available alognside regular maps. The most useful was the BW one, with a magnifier every terrain feature was perfectly detailed and precision navigation with those maps was a total joy, no gps was needed, and even after walking all night long with no moon and no night vision, guided by starts, at dawn one could exact the precise place by taking a look to the BW map and identifiying the stone one was treading. With other maps position was also located, but with the BW ones there was no doubt from exact feature identification. Color maps were nicer, but those that worked were the BW ones, of course, no doubt. No guess, I was there.

    Also all intelligence was based in BW photographs allowing identification of "enemy" assets from high altitude covering a large area.

    Of course all terrain has been photographed in color and BW, but military intelligence was using BW shots.
    Last edited by Pere Casals; 19-May-2020 at 01:58.

  9. #39
    Drew Wiley
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    Re: Resolution Comparison Between Films?

    Ho hum. You seem to be confusing this with a Boy Scout outing, Pere. Please tell me something I didn't already know when I was 8 years old. I grew up getting from Point A to B in the wilderness, my dad had been an expert surveyor, one of my teenage hobbies was borrowing aerial stereo shots and intensely studying them and specialized making maps from them myself, and then when I moved here to the coast and my nephew moved in with me, he earned his way through school doing mapmaking for the USGS, NASA (moon), and then private map distributors. I studied geological mapping in college. Now go tell me how battles are fought on horseback with bows and arrows. About all I can sum this topic up with is the hypothesis my older brother long held, that certain state of the art consumer films are simply military films which were declassified once something even fancier came along for their use, or, to rephrase it, the underlying technology was somehow repurposed for consumer use. I really don't know; I'm not a film chemist. And no, nothing I've ever personally seen looked like a tricolor camera shot; that is something I would recognize. And no, I'm not thinking about 300lp/mm color film; that was back was in the stone age. It's a fun topic, but largely irrelevant to what we do with view cameras, thank goodness.

  10. #40
    (Shrek)
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    Re: Resolution Comparison Between Films?

    I'm not going to comment or speculate on military technology, but for a couple of years I experimented with a Konica imagesetter infrared film, on a rather thin base. There was a very noticeable difference in resolution between that film and anything else I've ever shot. I gather that's why people still pay high prices for long-expired Kodak Tech Pan.

    Of course that's not why I shoot large format. If all I cared about was resolution, I would buy the latest dSLR and fancy lenses and not have to worry about chemicals and scanner resolution.

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