Author Topic: green laser pointers  (Read 1558 times)

joelin02

  • Observer
  • Posts: 16
    • View Profile
green laser pointers
« on: September 18, 2016, 10:17:04 PM »
So since Calstar is a big group event, green laser pointers are not permitted correct?

If I want to do some imaging with a dslr w/long lens and I need to figure out what I'm aiming at ... I normally use a green laser pointer. Are there any other less intrusive options?

DDK

  • Observer
  • Posts: 288
    • View Profile
Re: green laser pointers
« Reply #1 on: September 19, 2016, 10:22:13 AM »
Ah yes Joe, you've anticipated correctly. Use a green laser pointer, get tied to a tree.
TAC - astro anarchy at work <*>

John Pierce

  • WebHack
  • Administrator
  • Observer
  • *****
  • Posts: 274
    • View Profile
Re: green laser pointers
« Reply #2 on: September 19, 2016, 02:41:21 PM »
Joe, are you doing piggyback photography, where hte camera is mounted alongside a telescope, to use the telescopes tracking ?   before dark, align the camera with the telescope so they are both looking at the same thing.    that and take some trial exposures and see what you get.

joelin02

  • Observer
  • Posts: 16
    • View Profile
Re: green laser pointers
« Reply #3 on: September 19, 2016, 06:08:48 PM »
I've got an iOptron Skytracker where I'll put a Nikon D600 and 180mm f/2.8ED lens.

Polar aligning is easy, aiming it correctly is quite difficult...

richozer

  • Observer
  • Posts: 23
  • My brain hurts
    • View Profile
Re: green laser pointers
« Reply #4 on: September 19, 2016, 07:16:36 PM »
Bright stars are always visible in the camera.  I align a bright star with my red dot finder, optical finder, and camera, and I'm good to go.  I've absolutely never needed a green laser pointer. We hate's 'em, except in the daytime.  At night-time, they tend to go missing and often find new life as a swizzle stick.
Rich Ozer of the Ozer clan.

richozer

  • Observer
  • Posts: 23
  • My brain hurts
    • View Profile
Re: green laser pointers
« Reply #5 on: September 19, 2016, 07:29:09 PM »
Joe, now I see what you are doing, and why you feel the need for the laser pointer.  Since you don't have a scope on the system and your camera is mounted directly on the ioptron, instead of a laser, why don't you pick up one of these:

http://scopestuff.com/ss_slrf.htm

It fits in any SLR hot-shoe.
Rich Ozer of the Ozer clan.

John Pierce

  • WebHack
  • Administrator
  • Observer
  • *****
  • Posts: 274
    • View Profile
Re: green laser pointers
« Reply #6 on: September 19, 2016, 07:32:36 PM »
or just take 30 second iso1600 f/2.8 test shots and preview them til you get the framing right...

joelin02

  • Observer
  • Posts: 16
    • View Profile
Re: green laser pointers
« Reply #7 on: September 21, 2016, 06:25:56 AM »
Thanks for the replies. Did you ever find it difficult to either:

1) look behind a red dot finder? Especially when it was pointed towards the zenith?
2) figure out what you were shooting based on the resulting shot? This more so applies when you're using a telephoto and you might be off by as much as 10 degrees from your target...

DDK

  • Observer
  • Posts: 288
    • View Profile
Re: green laser pointers
« Reply #8 on: September 21, 2016, 07:03:02 PM »
You guys, this is a TAC imaging thread. John and Rozerman, you oughta know better. And CalStar starts a week from tomorrow, have some respect!
TAC - astro anarchy at work <*>

smigol

  • Observer
  • Posts: 33
    • View Profile
    • Blog
Re: green laser pointers
« Reply #9 on: September 22, 2016, 03:54:31 PM »
Joelin,

One method I found to solve the whole problem with finding the way around the sky was to use plate solves and re-slew to the target.  Once the stars are in focus, you can have software analyze the RAW file, show where the camera is really pointed, then re-slew to the proper target.  Sometimes this can be the only way to point to some really faint stuff.  Saves a lot of frustration!

Software I've used for this task:
Maxim
The Sky X (their all-sky platesolve is pretty fast)

I know that tools like Astrotortilla can be configured to use a local database rather than the internet.

Since you're probably autoguiding, you may also be using tools like Backyard EOS (correction: the Nikon version), which might integrate into other solving tools.

Stephen