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Thread: 100 monkey lens design vs. research

  1. #1

    100 monkey lens design vs. research

    I was going to add this to Daryl's close-up lens stuff, but it diverges too much,even for a divergent individual like, uh, where was I ?

    I think alot can be accomplished thru the (my?) 100-Monkey camera/lens theory/philosophy (100 monkeys in an optical lab may eventually build a Hasselblad, ok, maybe a Kiev), but there is too much to go awry when there is only one monkey in each lab. Parallel processing doesn't help much here.

    Ook, I diverge...

    Here are some interesting readings to guide one's simian illuminations:

    Use Google Patent for direct pdf download.

    US Patent 79323 Dallmeyer's Wide Angle Rapid Rectilinear design (essentially the same as Steinheil's Aplanat)

    US Patent 3006248 Walter Linke/Bell & Howell Wide Angle lens

    US Patents 4932764 and 5604639 discuss a variety of inexpensive single use 2-element camera lenses with combinations of meniscus, biconvex and aspheric, not necessarily to mimic but to learn from. Both of these discuss cylindrical film planes, another topic of interest to us.

  2. #2
    500+ Posts Daryl's Avatar
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    100 monkey lens design vs. research

    Very interesting there Murray! The Rapid Rectilinear was a Doppel-Anastgmat.

    The Hypergon according to the Vade Mecum was "f22 to view f/32 to expose...... A unique ultra-wide angel lens, with two deeply durved glasses only,. It covers up to 140 degrees but with severe fall-off in illumination dure to the cos-4 dependence." But the specimen I have witnessed said, "doppel-anastgmat" which would mean 4 elements in 2 groups as opposed to 2 elements in 2 groups.

    Maybe I should strive for a 30 mm lens for 4x5? And maybe use some sort of homemade smoked center filter?

  3. #3

    100 monkey lens design vs. research

    A piece of film can be exposed through the lens and developed for a contrast index of about 1. This can be mounted at about the focal plane for a center filter.

  4. #4

    100 monkey lens design vs. research

    That sounds good Jim.

    Well, they're not really monkeys I guess, but I got lost earlier and ended up at one of Jim's posts on a Photochimps site.

    I think I'm gonna give that Dallmeyer formula some more thought. A couple off-the-shelf achromats and very little math looks pretty easy. I wonder how far those have to be stopped down...not a problem, just wondering...I don't pay much attention to the big brass ones on the market due to demand/price issues. If I did, I'd know what f/# they were typically made in.

    Probably another dead-end thought, but I was imagining making a Hypergon-style fan...it doesn't look too complex...I wonder how much effort they put into the shape of the 'blades'.

  5. #5

    100 monkey lens design vs. research

    Oh, anyone interested in the variations of mapping lens of the Metrogon style (Zeiss Topogon and a British one), I have the patents zipped (and the B&L test data for my 12" Metro cell set) at

    http://uptowngallery.org/Murray/Metrogon/

    Commonly called a 4-element lens, the are 5-element Metrogons described in the patent, one being a simple optically flat glass plate (to shift something I guess, or add some asymmetry).

  6. #6

    100 monkey lens design vs. research

    Oh Yeah!
    Thanks for putting those up Murray!
    I've been looking for detailed metrogon stuff for awhile.
    of course finding the glass should be fun...

  7. #7

    100 monkey lens design vs. research

    Can anyone point me to some detailed diagrams for
    a ross homocentic or variants.
    The ROC seem a little less extreme so I think appropriate glass
    should be easier to get.
    I'd like try to take one of those designs (or a metrogon luck willing)
    and tweak one side of it for more landscape oriented stuff.

    or just shove a bunch of glass that looks about right in tube and go!
    fun is as fun does.

  8. #8

    100 monkey lens design vs. research

    Do you mean using the glass once found would be fun or do you consider them hard to find now?

    I guess not common, anyway. Surplus Shed occasionally gets weird versons in, including Japanese ones, maybe Fuji?

    The most recent ones they had were in a very different mount than the (K-17?) cone thingy, and might have even been fixed aperture, no shutter.

    There is a guy with a page called 20megsfree,metrogon or similar. He has I believe a 12" one in a machined mount & possibly a 6". Don't see alot posted on these.

    There is a SKGrimes-mounted on in a #5 shutter being sold (ha-ha, listed, I mean) on eBay by the Hollywood-based "Camera$" for the assinine price of $1300. Everything that guy sells is priced, to me, insanely. Makes me think Camera ^@*&@#. Home of the $500 2x3 Speed Graphic etc. There is a guy in the Czech Republic too that wants several hundred dollars for 6x9 folders worth to me 1/10 the price. Gotta wonder...

    I don't wanna talk about my Metro stuff here...not ready to use, not unwanted either. I guess PM me if you neeed to know what kind of mental condition causes Metrogon hoarding. (Hypothetically speaking, or course).

    M

  9. #9

    100 monkey lens design vs. research

    HaHa!
    Delusional (or perhaps just predatory) ebayer prices always crack me up too.

    Re: Metrogon: Not looking so much for mounted finished pieces as
    appropriate glass components for wide field experiments.

    like you said, I know they pop up fairly often as complete lenses
    (well from a glass standpoint) but individual elements with
    deep deep curvature, not so much.

    Oh yeah, hows the petzvahl coming? (PM me)

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