Re: Telescopes for astrophotography


"Mark S. Holden" <mark@xxxxxxxx> wrote in message
news:TcKdnXgDM-_CaZ7eRVn-jg@xxxxxxxxxxxxxxx
> Timothy Stark wrote:
> > Hello folks,
> >
> > I was shopping for new telescopes for astrophotography for planets,
moon,
> > and deep sky. I looked at some Celestron/Meade telescopes. Does anyone
> > have any experiences with Celestron S-GT and CPC and Meade LX90 and
> > LX200GPS? I am considering Celestron C8S-GT or C925S-GT. Which
telescopes
> > can handle long-expurose with my Nikon D70 for deep sky?
> >
> > I recently read astronomy magazines and noticed that Newt and SCT are
best
> > for astrophotography. Well, I forget to tell something about Newt. Can
> > Newt handle long-expourse for deep sky?
> >
> > Thanks!
> > Tim
> >
> >
>
>
> For time exposures, the mount will be a significant factor. You'll want
> an equatorial mount with provisions for talking to an auto guider.
> (You'll want an autoguider for exposures longer than about 2 minutes)
>
> As for the type of telescope, I like apo refractors for deep sky
> photography. No central obstruction, and the faster F ratios cut down
> on the exposure time. I like them for planets too, but you need a
> monster to get a good image scale.
>
> The D70 is good for the Moon, but you're likely to prefer a webcam for
> planets. (The web cam can be used with a laptop to create your
> autoguider for deep sky)
>
> In round numbers, if you look at a planet through a scope with a 28mm
> eyepiece, that's about what the D70 chip will see at prime focus. A
> webcam is more like a 5mm eyepiece.
>

Cool. How do you come up with those numbers? Is the webcam like a 5mm
eyepiece because the webcam has a smaller sensor than the DSLR?

Thanks,
Greg


.

Relevant Pages

  • Re: Telescopes for astrophotography
    ... I was shopping for new telescopes for astrophotography for planets, moon, and deep sky. ... Does anyone have any experiences with Celestron S-GT and CPC and Meade LX90 and LX200GPS? ...
    (sci.astro.amateur)
  • NASA studies space railway to explore origins of planets, stars, and galaxies (Forwarded)
    ... NASA STUDIES SPACE RAILWAY TO EXPLORE ORIGINS OF PLANETS, STARS, AND GALAXIES ... SPIRIT will consist of two telescopes at opposite ends of a 120-foot ...
    (sci.astro)
  • Re: Scientific Accuracy of Quran amazes you
    ... musings of children in the dark. ... I do agree that most planets are likely formed around stars, ... you have your ultrastable platforms and have telescopes 1km or 10km ...
    (sci.space.policy)
  • Re: Telescopes for astrophotography
    ... the deep sky photos you posted links to were done with a modified camera. ... The reasons I suggest a webcam for planets are image scale, ... A DSLR has a much larger chip, and you'll need a longer focal length scope to have a planet fill a significant part of the frame. ... You could use a powermate, barlow, or eyepiece projection but then you'll need a longer exposure, and seeing conditions become more of a factor. ...
    (sci.astro.amateur)
  • Re: NASA studies space railway to explore origins of planets, stars, and galaxies (Forwarded)
    ... >NASA STUDIES SPACE RAILWAY TO EXPLORE ORIGINS OF PLANETS, STARS, AND GALAXIES ... >SPIRIT will consist of two telescopes at opposite ends of a 120-foot ...
    (sci.astro)