Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: Help understanding brass lenses

  1. #1

    Join Date
    Sep 2016
    Posts
    4

    Help understanding brass lenses

    Help! I'm new to wet plate photography and am really struggling understanding brass lenses and whether or not they will fit on my 8x10 wet plate camera. I'm looking for a landscape lens but confused by the descriptions I have seen on eBay.

    Also, do I have to use a brass lens with a flange or can I use something else like the Nikor ones I have seen on eBay?

    Thanks in advance!

  2. #2

    Join Date
    Dec 2000
    Location
    Tonopah, Nevada, USA
    Posts
    5,780

    Re: Help understanding brass lenses

    It depends (of course) on what you're visualizing. If very soft corners are OK, any achromatic doublet (think edmonds scientific and their ilk) of about 1X the diagonal across the 8X10 plate should do nicely. 12" focal length. cobble it onto a lens board and have at it. If you dislike soft corners, the longer the focus, the bigger the center sharp area will get. And 18" achromatic meniscus doublet makes a nice 8X10 normal lens. If you buy a meniscus doublet somewhere (#2 dioptor on ebay) and cobble it onto a lens board, make a shade painted flat black to extend out past the lens to help with non image forming light hitting the glass. If you wind up with a more sophisticated lens like an early brass petzval, put the front group by itself at the rear, and voila, a landscape lens. So, no you don't have to follow any rules or even spend very much money.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

  3. #3
    Jac@stafford.net's Avatar
    Join Date
    Dec 2012
    Location
    Winona, Minnesota
    Posts
    4,079

    Re: Help understanding brass lenses

    Oi! Jim Galli's post should be cast in steel.
    .
    I will add that many, many of the 'old brass lenses' are fast compared to the same focal lengths today. Image making with slow emulsions will introduce you to the original challenges. Enjoy!

  4. #4

    Join Date
    Sep 2016
    Posts
    4

    Re: Help understanding brass lenses

    Wow thanks so much for the quick responses and great info...I have a lot of studying to do but I think I'm catching on now. Also just realized why I have been struggling so much - they are all in mm of course...woops. I've got a picture of a lens I bought on ebay but having trouble uploading... 180mm that said would fit up to a 10x12. Based on what you're saying I think it should be a nice wide lens for landscapes which is what I wanted....no?
    Attached Thumbnails Attached Thumbnails IMG_1621.jpg  

  5. #5

    Join Date
    Dec 2000
    Location
    Tonopah, Nevada, USA
    Posts
    5,780

    Re: Help understanding brass lenses

    Probably great for film but it will be rediculously slow for wet plate. Wet plate is such a slow asa equivalent that you'll need something with at least an f5.6 maximum aperture (slow for wet plate standards). f4 petzvals were invented so that wet plate photographers could get portraits down into the 1 - 3 second range. Landscape that is static can take more time. Nothing like getting your feet wet in some kind of workshop setting where folks are doing what you're aspiring to do. You can make huge gains in your knowledge base that way.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

  6. #6

    Join Date
    Nov 2006
    Location
    CA Central Coast
    Posts
    585

    Re: Help understanding brass lenses

    No excuse for letting mm mess you up.
    But here's a lesson really easy and not exact
    25mm is one inch
    thus normal lens for 8x10 is 300mm- you do the math
    Your quote of
    "180 mm fits 10x12"
    is a whole nother story
    Is it really a very sloooooow very wide angle???
    I strongly suggest you follow Jim's excellent advice untill you get some basic knowledge about lenses
    focal length, normal for a format, wide, long. etc
    There is a lot of basic information on this site, probly at the top of this page
    And you can have a lot of fun with Jim's advice while you sort the rest out
    Jim is very cool

  7. #7

    Join Date
    Apr 2011
    Location
    Leipzig, Germany
    Posts
    474

    Re: Help understanding brass lenses

    Brass is a metal alloy, not a lens type. A wide range of vastly different lenses were mounted in brass. Try to find out what lens you need and then worry about the brass.

    You could start here: The lenses you have mentioned are either "normal" lenses with a limited angle of coverage. The focal length will determine the format you can use. Or they are wide angle lenses, with a wider angle of view to cover larger formats at shorter focal lengths. Unless you are planning to shoot architecture or tight spaces, they away from wide angles for now, because they are not very fast. If your 180mm really covers 10x12" and not 10x12cm, it probably opens up to f18. Not fast at all. Especially not for wet plate.

    I would also suggest you do your research here or at other competent places. Ebay descriptions are just as often fiction as they are free of facts. That the lens is mounted in brass is the only thing I would believe. For the start, stay away from unmarked lenses, unless you really know what you are doing or love surprises. Famous "silver bullet" lenses can be very expensive, bread-and-butter lenses often do the job very satisfactorily. A 300mm f4.5 Zeiss Tessar delivers sharp images edge to edge when stopped down, gives a pleasing bokeh when used wide open, is fast enough for wet plate, doesn't cost much (especially in the late East German rendition), but rarely comes in a shiny brass barrel.

    About the lens flange: No, you don't necessarily need one. I usually make my own lens boards out of soft plywood (or mat board for testing), cut the hole with a jig saw and just screw the lens into the soft material. A hot glue gun also works wonders (hot glue can be removed - very important!). Fast lenses are usually heavy, so try your kludge with caution.

  8. #8
    Mark Sawyer's Avatar
    Join Date
    Jul 2004
    Location
    Tucson, Arizona
    Posts
    5,136

    Re: Help understanding brass lenses

    Quote Originally Posted by Wadmalaw View Post
    Help! I'm new to wet plate photography and am really struggling understanding brass lenses and whether or not they will fit on my 8x10 wet plate camera. I'm looking for a landscape lens but confused by the descriptions I have seen on eBay.
    Just to get everyone on the same page, there are different uses of the term "landscape lens". On this forum, we generally use the term for the traditional single cell landscape lens, be it the single element Wollaston Landscape Lens, or the cemented achromatic doublets of English or French Landscape Lens. I think the OP simply wants an old brass lens suitable for landscape photography, like the wide angle rectilinear like the one he posted a photo of.

    In the larger photography world, any wide angle lens is a "Landscape Lens, any long focal length lens is a "Telephoto Lens" and any lens you use to take a portrait is a "Portrait Lens". But around here, most of us lens nerds know as second nature that all of those definitions are technically wrong.
    "I love my Verito lens, but I always have to sharpen everything in Photoshop..."

  9. #9

    Join Date
    Aug 2000
    Location
    California
    Posts
    2,480

    Re: Help understanding brass lenses

    Jim,
    When are you going to slow down long enough to gather all of the notes similar to the one above into a booklet?
    Little tidbits like this are very valuable to those of us attempting to learn more about the use of soft focus lenses.
    Jim

  10. #10

    Join Date
    Dec 2000
    Location
    Tonopah, Nevada, USA
    Posts
    5,780

    Re: Help understanding brass lenses

    Quote Originally Posted by Jim Noel View Post
    Jim,
    When are you going to slow down long enough to gather all of the notes similar to the one above into a booklet?
    Little tidbits like this are very valuable to those of us attempting to learn more about the use of soft focus lenses.
    Jim
    A fine compliment Jim, thanks, but I'm going in the wrong direction. Antique cars and Bible exposition are taking most of my time these days.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •