Page 1 of 7 123 ... LastLast
Results 1 to 10 of 64

Thread: Large format Astrophotography

  1. #1
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    2,381

    Large format Astrophotography

    Here is the first step in practicing before hooking up to the the telescope for prime focus imaging.

    Next us making adapter to hooking up to telescope itself. If I want full frame coverage will need a lens that throws a huge image circle, but won't further reduce the f-ratio from like 8. Not sure how putting to f/8 objects would add. Not well. Image light already at f/8. So if put another f/8 or f/16 I suspect it will be like shooting at f/24 or f/32. Doable, but painful.
    Attached Thumbnails Attached Thumbnails 37941817-EEB3-4AC7-9C3F-5E85C6B6E1F1.jpg  

  2. #2
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    14,533

    Re: Large format Astrophotography

    Whoa!

    Steven this is interesting AND Large Format!
    sin eater

  3. #3
    Drew Bedo's Avatar
    Join Date
    Oct 2006
    Location
    Houston Texas
    Posts
    2,600

    Re: Large format Astrophotography

    I say "Go For It!"

    back in the early 1990s I cobbled together a bracket to mount an old press camera behind a B&L Discoverer spotting scope. Had it set up to project the eyepiece image directly onto the film plane through a shutter with no lens elements.

    Guessed at the exposures. Got a few interesting images of the sun rising behind an agricultutal windmill. Got a few of the moon setting behind a different windmill. Interesting I say, but not great. Too much guessing. Never did any real astrophotography with it.

    The 8x10 set up is impressive. I really hope to see images from this rig. I would worry about vibration as the telescope tracks the astro target. My 8x10 2D is shaky even when locked down. . . .and it is in good shape.

    I would think that dropping back to 4x5 would help with that as all the parts are lighter and less suseptable to vibration. Even further; I might use a even more rigid camera such as a TravelWide coupled directly behind the telescope.

    Best wishes in this. Tells us about it and show us what images you get.

    Cheers
    Drew Bedo
    www.quietlightphoto.com
    http://www.artsyhome.com/author/drew-bedo




    There are only three types of mounting flanges; too big, too small and wrong thread!

  4. #4
    Corran's Avatar
    Join Date
    Apr 2011
    Location
    North GA Mountains
    Posts
    7,683

    Re: Large format Astrophotography

    I'm picking up a Celestron C8 next weekend. Plan to try some wide-field images with 4x5 strapped on the back.

    Telescope won't even cover my full-frame sensor. Why not just use your LF lenses? What do you want to photograph? I plan to use my 250mm f/5.6 Zeiss, maybe Nikkor 450mm f/9.
    Last edited by Corran; 3-Aug-2020 at 12:52.
    Bryan | Blog | YouTube | Instagram | Portfolio
    All comments and thoughtful critique welcome

  5. #5
    umop apsidn
    Join Date
    Mar 2007
    Location
    Texas
    Posts
    111

    Re: Large format Astrophotography

    I love using my 4x5 for astrophotography. Been at it for a couple decades now. I was just out last month with this getting some exposures made!
    Attached Thumbnails Attached Thumbnails 45Astro2.jpg   45Astro.jpg  

  6. #6
    Corran's Avatar
    Join Date
    Apr 2011
    Location
    North GA Mountains
    Posts
    7,683

    Re: Large format Astrophotography

    Please share your work!
    Bryan | Blog | YouTube | Instagram | Portfolio
    All comments and thoughtful critique welcome

  7. #7
    umop apsidn
    Join Date
    Mar 2007
    Location
    Texas
    Posts
    111

    Re: Large format Astrophotography

    Quote Originally Posted by Corran View Post
    Please share your work!
    These are some quickly made 8x10 prints from my darkroom. The film enlarges beautifully corner to corner sharp at 16x20.
    Attached Thumbnails Attached Thumbnails Rho.jpg   Sum-Tri.jpg   Scrp-Sag.jpg   Scrp-Sag-Neg.jpg  

  8. #8
    Corran's Avatar
    Join Date
    Apr 2011
    Location
    North GA Mountains
    Posts
    7,683

    Re: Large format Astrophotography

    Nice, thanks! I like the one of Rho Ophiuchi especially. I really want to try shooting that area on color. The images I've seen online are fascinating. Perhaps you can share details on lenses - looks like a 90mm f/5.6?
    Bryan | Blog | YouTube | Instagram | Portfolio
    All comments and thoughtful critique welcome

  9. #9
    umop apsidn
    Join Date
    Mar 2007
    Location
    Texas
    Posts
    111

    Re: Large format Astrophotography

    Corran, I have and use a 90mm f/5.6, 180mm f/5.6, 300mm f/5.6. Please be wary that lens samples vary a lot. It took me many years to find some examples buying, testing, trading to find some that performed well from the center to all the way out in the corners. That corner sharpness and a lack of distortion there was key and important to me. Manufacturing tolerances, lenses are dropped and/or had a hard life before being sold. The lenses can be fabulous for day to day work, landscapes, general use, but stars are an utter torture test of optical performance.

  10. #10

    Join Date
    Jan 2019
    Posts
    182

    Re: Large format Astrophotography

    Long story but small telescopes for amateur / visual use generally don't have a large field of coverage, or a large back focal distance. (Unless you obtain a relatively rare and $$ telescope designed for astrophotography.) Meaning one may need reimaging lenses to bring the image from the telescope focus to the detector, and to expand the image size. This is basically what eyepiece projection does for small format astrophotography, but one would need something much bigger for 4x5. Much care is needed in designing a reimager to match focal ratios, avoid vignetting, etc.

    Large format astrophotography with a lens as prime imager and using the telescope to guide, seems like a potential application for those big, fast-ish lenses that have no shutter or no iris and that nobody really knows what to do with. Like the f/4.5 or f/5.6 copy lenses that are always floating around. I don't know how well they perform at infinity. Of course, aerial camera lenses might be a contender.

Similar Threads

  1. Astrophotography and Chamonix 45N-1
    By AlexHanson Photos in forum Cameras & Camera Accessories
    Replies: 14
    Last Post: 17-Apr-2018, 09:37
  2. Astrophotography with the Travelwide 4x5?
    By plywood in forum Cameras & Camera Accessories
    Replies: 17
    Last Post: 25-Sep-2015, 09:35
  3. Film for Astrophotography
    By tgtaylor in forum Style & Technique
    Replies: 20
    Last Post: 3-Nov-2009, 19:34
  4. 4x5 Astrophotography?
    By neutronman in forum Cameras & Camera Accessories
    Replies: 10
    Last Post: 7-Sep-2009, 19:09

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
  •