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  1. #1

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    Researching home-made lenses

    Hello everyone! My name is Justin, as this is my first post it's obvious that I am new to the APUG forums. I have been shooting 35mm for a few years, but the place I am living in now does not have enough space for a dedicated darkroom, so I had purchased a DSLR. It's nice, but it is significantly lacking in 'magic', so I have decided to make a greater effort with film. I just purchased a Crown Graphic 4x5 off ebay for a great price, and although it will be a while before I can get together the film holders, lensboard, lens, and a tripod that can support it, I am very excited and looking to try various alternative processes, especially Van Dyke and platinum/palladium.

    One other area that has peaked my interest is going to the extreme end of the homebrew theme and building my own camera and lens for a ULF size, such as 11x14 or even larger. After researching the camera bit it seems that given enough time after a few tries I could get something pretty usable. The main concern would be finding lenses to fit the camera, and not having to spend a large amount in one shot, as I am currently a broke student. I've downloaded some programs from the Linos Photonics (Rodenstock) website, Pre-Designer, and WinLens 4.4, whcih are really interesting, but am having a hard time grasping the basics. I have also downloaded several books from the late 19th/early 20th century on lens and optical design from archive.org, and gone through some books at the university library, but since I don't have an extensive physics background they go right over my head.

    I'm not expecting great, or even good results, and will keep my efforts to a barrel lens with waterhouse stops, using a cap for the shutter, since I figure any lens could beat a pinhole for combined image quality and shorter exposure times. Not to mention it would be pretty freakin' cool, and a great chance to learn more about the science of photography. Has anyone here ever attempted this before? How about knowing of any good resources for getting a handel on simple optics? I read through a Rudolf Kingslake book, I think it was called 'Elementary Lens Design', but it was more accurately called, "Elementary Lens Design for Physics Majors", LOL... I do expect it to take a while, but figuring these things out is half the fun!

    Thanks for the help, and I apologize if this is not the correct section of the forum to post this in. I'm looking forward to spending much more time on here than is healthy for me!

    BTW, if anyone hasn't been to archive.org before, it is an amazing site. Aside from the archive of websites, they have a collection of films, some new, some quite old, and particularly interesting the Prelinger archive collection of ephemeral films from schools, businesses etc... For photo or movie-film related items look for Photography, Behind the Lens, Alchemist in Hollywood, and others. Alchemist in Hollywood is particularly interesting for a look at motion picture film processing in the 40s. Be warned, some of the films on the site can be quite graphically racist or sexist, to the point where they seem more like a Saturday Night Live sketch than a serious lesson. Look for The Girl on the Magazine Cover to see what I mean. The text section also contains many interesting books that have passed in to public domain, including many related to photography.

    Cheers!
    Justing

  2. #2
    Lee L's Avatar
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    This book: http://www.amazon.com/Primitive-Phot...6124350&sr=8-1
    has been mentioned on APUG before, and its merits debated. You might find it interesting as a first foray into DIY lenses. Some don't like its approach, mostly because it's not technical enough or a bit misleading as to exact nomenclature on lens types. However, it will provide some affordable large format camera and lens designs using lens combinations in PVC pipe barrels with paper or cardboard stops and foamcore spacers. I'm sure someone will tell you that buying old brass barrel lenses is cheaper and will provide better results. That also may be perfectly true, but if you want to build your own, this book is a good starting point.

    Lee

  3. #3

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    I'll second "Primitive Photography". As stated, it's not 100% accurate, but it will get you close enough.

    The wikipedia site has some basic info as well. The multiple lens formula is is useful when combining off-the-shelf elements from places like Anchor Optical or surplusshed.com

  4. #4
    reellis67's Avatar
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    I too have that book, and if you were looking for something to jump-start your experiments, this is a great place to start. He's got some interesting ideas in there and they seem to work quite well.

    - Randy

  5. #5
    Jim Jones's Avatar
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    Good large format photography was done well over a hundred years ago with a landscape lens, much like the cemented doublet achromat in the better box cameras. The modern close-up attachments (sometimes called close-up filters or dipopter attachments) are somewhat similar. The very best of these are cemented doublets. Strong filtering can reduce the effect of chromatic aberration in simple lenses. Very small apertures can reduce some other aberrations. Such lenses should have the convex surface towards the film, with the aperture in front of the lens. The optimum spacing between lens and aperture might best determined for a particular lens by experimentation.

  6. #6

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    Justing:

    You might find the f295 forum on homemade lenses of interest:

    http://www.f295.org/DIYforum/cgi-bin...Blah.pl?b-len/


    Charley

  7. #7

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    g'day Justin

    i've been doing a lot of work in the last 2 years with a homemade simple lens camera using a magnifying glass for the lens

    what started as a simple project to create LF negs for alt printing has turned into an ongoing obsession
    Last edited by Ray Heath; 12-04-2007 at 02:49 PM. Click to view previous post history.

  8. #8

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    Justin,
    why not forgo the 'pleasure' of making your own lens, and just use a pinhole?

  9. #9

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    Quote Originally Posted by markbb View Post
    Justin,
    why not forgo the 'pleasure' of making your own lens, and just use a pinhole?
    g'day Mark and Justin

    if i may,

    pinholes and simple lenses create different images and are used differently

    a pinhole image is kinda sharp with incredible depth of field, a simple lens creates an image that can be very sharp in the centre and soft on the edges

    a pinhole image is what it is, a simple lense's degree of softness can be controlled by aperture

    an image created by pinhole may need an extremely long exposure, especially with paper negs when the paper has an effective ISO of 6, where as a simple lens exposure can be much shorter

    so, they are different, one is not better than the other, they just create a different aesthetic

  10. #10

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    Grinding the optical glass into appropriate shapes I would assume could be a daunting task without proper lab equipment, however there are available various single optical elements in different types available from vendors, such as possibly Edmund Scientific, which possibly could be assembled into a lens with fairly good qualities.

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