Results 1 to 2 of 2
  1. #1
    ccormsby's Avatar
    ccormsby is offline White Dwarf
    Points: 40, Level: 1
    Level completed: 80%, Points required for next Level: 10
    Overall activity: 20.0%
    2 Posts Achievement
    Join Date
    Nov 2019
    Kennebunkport, ME
    Thanked 0x 0 Posts

    Default Estimating maximum exposure times

    I have found one model (by Bill Keicher, 12 March 2005) that purports to estimate maximum exposure times for an AltAz mount as a function of the AltAz of the target, the telescope's parameters & the camera/focal plane parameters. While I have produced a convenient spreadsheet/table of these exposure time limits, I am looking for some independent validation of the formula in that model. Predictions from that model indicate that exposures up to several minutes are possible for targets at relatively low altitudes if thet at azimuths near east/west. Is this a generally accepted model or are there better models?

  2. #2
    Pauls72's Avatar
    Pauls72 is online now HYPER GIANT
    Points: 19,616, Level: 96
    Level completed: 79%, Points required for next Level: 84
    Overall activity: 14.0%
    First 1000 Experience Points365 Days+ Registered Achievement!750 Days+ Registered Achievement!1000 Days+ Registered Achievement!3 Years + Achievement
    Join Date
    Jul 2009
    LaPorte, IN USA
    Thanked 663x 514 Posts

    Default Re: Estimating maximum exposure times

    The rule of 500 is what is commonly used.
    Maximum Exposure Time = 500 / Crop-Factor x Focal Length
    Mounts: EQ1, LXD55, Atlas EQ-G (one with Rowan belt mod, EQ6-Rail and one without)

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    C11, 8" Reflector, 102mm MCT, ST80, W.O. FLT98, 6" RC, Lunt LS50THa/B400
    Cameras: Canon XTi, DSI-C, DSI, ST402, QHY8L, QHY183C, QHY163M, ASI120MC-S (Allsky)
    Some of my Pic's



Similar Threads

  1. Determining Maximum Exposure
    By davidjbillo in forum Astro Imaging Forum
    Replies: 3
    Last Post: 02-25-2014, 08:09 AM
  2. exposure times
    By Sgb2164 in forum CCD Imaging Forum
    Replies: 4
    Last Post: 12-13-2013, 09:44 AM
  3. Help on maximum practical exposure times
    By ToxicTraveller in forum Astronomy Beginners Forum
    Replies: 23
    Last Post: 04-15-2013, 11:25 PM
  4. Maximum Exposure Time - Shooting the Moon
    By joe4444 in forum Astro Imaging Forum
    Replies: 4
    Last Post: 03-26-2011, 03:31 PM
  5. Estimating Planetary Cooling Times
    By Widdekind in forum Planetary Forums
    Replies: 11
    Last Post: 05-31-2009, 07:57 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Powered by vBulletin® Version 4.2.0
Powered by vBulletin®
All times are GMT. The time now is 12:31 AM.