Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Analysis Paralysis

Big images of DSO

Recommended Posts

One useful way to think about the size of the object on your PC screen is to think about how many pixels its image has landed on in the telescope.

The question of useful sampling rates is so intractable that I've given up on it. I simply don't know the point at which it stops being useful to go for fewer arcseconds per pixel. I'd have said that going down to about 0.4 was pointless until Julian Shaw kindly gave me this data to process...

SOMBRERO%20JULIANS%20DATA%20V2%20CROP-L.

By the way, this was at F15...

At the moment I'm imaging galaxies at about 0.9"PP using a refractor and separate guidescope. Even this is very sensitive to seeing, though. I may do only colour when the FWHM values are poor.

Olly

Share this post


Link to post
Share on other sites
7 hours ago, ollypenrice said:

One useful way to think about the size of the object on your PC screen is to think about how many pixels its image has landed on in the telescope.

The question of useful sampling rates is so intractable that I've given up on it. I simply don't know the point at which it stops being useful to go for fewer arcseconds per pixel. I'd have said that going down to about 0.4 was pointless until Julian Shaw kindly gave me this data to process...

SOMBRERO%20JULIANS%20DATA%20V2%20CROP-L.

By the way, this was at F15...

At the moment I'm imaging galaxies at about 0.9"PP using a refractor and separate guidescope. Even this is very sensitive to seeing, though. I may do only colour when the FWHM values are poor.

Olly

Wow! That image is fantastic. I wonder what aperture he used? I have seen a wonderful M51 taken with a Mak at F12, but I believe it was a 12 inch aperture, and I believe aperture is important, although I have seen very good 150 mm F12 M51 images, so I know it's possible. 

Mark

Share this post


Link to post
Share on other sites
2 hours ago, Analysis Paralysis said:

Wow! That image is fantastic. I wonder what aperture he used? I have seen a wonderful M51 taken with a Mak at F12, but I believe it was a 12 inch aperture, and I believe aperture is important, although I have seen very good 150 mm F12 M51 images, so I know it's possible. 

Mark

6 inch refractor plus Astro Physics Advanced Barlow.

Olly

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.