Page 3 of 4 FirstFirst 1234 LastLast
Results 21 to 30 of 39

Thread: Teach me about Lens Design

  1. #21

    Join Date
    Apr 2020
    Location
    Washington, DC
    Posts
    87

    Re: Teach me about Lens Design

    Good points, Bernice, much appreciated.

  2. #22

    Join Date
    Jul 2008
    Posts
    3,901

    Re: Teach me about Lens Design

    Image contrast is all over tonal scale in these four different images and images transmitted via web are no where near idea to "judge", but ok..

    Based on your mention of preferring the bottom right image and this head shot outdoors, going to make a totally biased recommendation and suggestion. Get a 10" f6.3 Kodak Commercial Ektar or 250mm f4.5 Xenar or similar tessar design lens. Suspect these will render closer to what
    you're after. Both the C. Ektar and Xenar are GOOD at f8, Xenar is softish at f4.5, C. Ektar is not softish at f6.3 full aperture.

    The single element convertible focal length about 265mm is a reasonable 4x5 focal length for a head shot like this.

    Problem might be, both the Kodak C. Ektar and Schneider Xenar might be a bit big on a 4x5 Technika to handle. The 10" Kodak Ektar is modernly common in shutter, the 240mm Xenar in shutter is not. There are a number of other 250mm_ish tessar View camera lenses in shutter similar in many ways to these two suggested. What ever lens is decided upon, testing is a MUST do. There is no way out of the testing, evaluating and deciding process before any individual lens is considered to be a keeper.

    Keep in mind there is reason why modern multi-coated view camera lenses have a high contrast, hard hitting image result often optimized for f22. It has much to do what who used a view camera during that time, the images expected and what the bulk of the market demanded from sheet film images. Majority of 4x5 view camera images from that era were for marketing-advertising. The fashion and expectation at the time was often hard hitting, eye poking images of color. Since this was what the majority of the market expected, this is what companies that made view camera lenses designed, produced sold. View camera back then was never a "hobby" film format, some tinkered in it, most were trying to put food on their table, roof over their head and studio and make ends meet producing advertising images and related. Essentially, all involved had to meet a specific level of quality and performance if they were to survive at all. This is why modern lensed produced by the big four are mostly similar and built to last the demands of daily image making day in, day out.

    This was not quite the image fashion and expectation one generation back, thus the lenses, film and images produced reflect this. Today that world has been flipped around where once monorail cameras used in a controlled studio setting has been mostly replace by field folders that were a niche market and were considered out of the main stream of view camera photography. Since then the field folder camera crowd has become the majority and a reflection of how the LF market and image makers have changed.


    Bernice



    Quote Originally Posted by giganova View Post
    I particularly like the image at the bottom right, which is a single-coated Schneider 150/265 convertible with the rear element removed. Look at the the softer skin and interesting bokeh:
    Last edited by Bernice Loui; 6-Aug-2020 at 20:22.

  3. #23

    Join Date
    May 2015
    Location
    SooooCal/LA USA
    Posts
    2,802

    Re: Teach me about Lens Design

    If on a budget, you can try Tessar types in a shutter by finding old Wollensak lenses that would go on SG'S or other cameras... Plenty of 127/135/150/210mm lenses to try for not much $$$... Sharpish, with a smoother rendering than modern lenses...

    You might like them!!!

    Steve K

  4. #24

    Join Date
    Apr 2020
    Location
    Washington, DC
    Posts
    87

    Re: Teach me about Lens Design

    Based on your recommendations, I bought a 1937 uncoated Carl Zeiss Jena Tessar 150mm f/3.5 lens in a Compur shutter that was recently CLA-ed. Shutter speeds sound good.

    Also bought a blank lens board and need to find a local machine shop to drill a 57mm hole in it. I actually bought two: one 3D-printed to test the lens and if I'm happy I'll permanently mount it in an original blank Linhof metal lens board that needs a hole.

    Now, in oder to use the lens wide open, I intend to use ND filters. Problem is that the lens seems to have a rather rare 50mm filter thread and filters in that thread are nowhere to be found. So I ordered a set of 52mm ND filters that I can put over the lens in reverse and use tape to secure the filter to lens. Not ideal but should work.

    Will post pictures soon, so stay tuned.

  5. #25

    Join Date
    Sep 1998
    Location
    Loganville , GA
    Posts
    14,409

    Re: Teach me about Lens Design

    Quote Originally Posted by giganova View Post
    Based on your recommendations, I bought a 1937 uncoated Carl Zeiss Jena Tessar 150mm f/3.5 lens in a Compur shutter that was recently CLA-ed. Shutter speeds sound good.

    Also bought a blank lens board and need to find a local machine shop to drill a 57mm hole in it. I actually bought two: one 3D-printed to test the lens and if I'm happy I'll permanently mount it in an original blank Linhof metal lens board that needs a hole.

    Now, in oder to use the lens wide open, I intend to use ND filters. Problem is that the lens seems to have a rather rare 50mm filter thread and filters in that thread are nowhere to be found. So I ordered a set of 52mm ND filters that I can put over the lens in reverse and use tape to secure the filter to lens. Not ideal but should work.

    Will post pictures soon, so stay tuned.
    LInhof boards, real ones, either have a 0, 1 or 3 hole or a pilot hole. No blank boards.
    You don’t drill a board, it’s milled. Your machinist would no or you could just have PromCamera in DC do it for you.

  6. #26

    Join Date
    Jul 2008
    Posts
    3,901

    Re: Teach me about Lens Design

    GOOD!

    Might be easier to make a test lens board out of heavy card board- mat board. If flat, this could be easier than 3D printing a lens board.

    Testing is the only way to really know if this individual lens is for you.


    Bernice



    Quote Originally Posted by giganova View Post
    Based on your recommendations, I bought a 1937 uncoated Carl Zeiss Jena Tessar 150mm f/3.5 lens in a Compur shutter that was recently CLA-ed. Shutter speeds sound good.

    Also bought a blank lens board and need to find a local machine shop to drill a 57mm hole in it. I actually bought two: one 3D-printed to test the lens and if I'm happy I'll permanently mount it in an original blank Linhof metal lens board that needs a hole.

    Now, in oder to use the lens wide open, I intend to use ND filters. Problem is that the lens seems to have a rather rare 50mm filter thread and filters in that thread are nowhere to be found. So I ordered a set of 52mm ND filters that I can put over the lens in reverse and use tape to secure the filter to lens. Not ideal but should work.

    Will post pictures soon, so stay tuned.

  7. #27

    Join Date
    Apr 2020
    Posts
    300

    Re: Teach me about Lens Design

    Quote Originally Posted by Bernice Loui View Post
    GOOD!

    Might be easier to make a test lens board out of heavy card board- mat board. If flat, this could be easier than 3D printing a lens board.
    Having carved a lens board out of corrugated cardboard, and 3D printed one, I can honestly say, the 3D printed board was easier-- Granted, I have a 3D printer, which puts me a step up, and linhof-style board designs can be downloaded. It didn't help when I discovered the cardboard was slightly translucent.

    Also, while I'd be willing to take the 3D printed board out in the field, the cardboard mock-up would never leave my house.

  8. #28

    Join Date
    Apr 2020
    Location
    Washington, DC
    Posts
    87

    Re: Teach me about Lens Design

    I found someone who sold me a 3D-printed lens board for $10, so I use that for testing. Is drilling a hole with a step-drill bit OK?

  9. #29

    Join Date
    Jul 2008
    Posts
    3,901

    Re: Teach me about Lens Design

    Do step drill bits go that large, think it was 57mm? Ideal way is to set up the board in a lathe and bore the hole to the size needed. Making a hole in plastic can be as difficult as aluminum.


    Bernice

    Quote Originally Posted by giganova View Post
    I found someone who sold me a 3D-printed lens board for $10, so I use that for testing. Is drilling a hole with a step-drill bit OK?

  10. #30

    Join Date
    Nov 2017
    Posts
    654

    Re: Teach me about Lens Design

    Easiest way is to fly-cut in a mill. Setting up a thin board like that in a lathe isn't that easy. Certainly as it isn't circular.
    Expert in non-working solutions.

Similar Threads

  1. Teach me to see soft corners...
    By Tim Meisburger in forum Style & Technique
    Replies: 22
    Last Post: 1-Feb-2015, 06:27
  2. teach me... Voigtlander soft focus (?)
    By Emil Schildt in forum Lenses & Lens Accessories
    Replies: 5
    Last Post: 31-Mar-2012, 11:30
  3. Teach me about Dagors?
    By Blumine in forum Lenses & Lens Accessories
    Replies: 70
    Last Post: 23-Nov-2008, 12:28
  4. Where does Jock Sturges teach?
    By Peter Shier in forum Style & Technique
    Replies: 4
    Last Post: 22-Apr-2002, 12:57

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
  •