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.


Recommended Posts

Hello, I have been spending as much time as possible outside when the weather permits practicing. My current camera is a Canon Rebel XS Astro modified by myself (IR-Cut Filter left in) w/ Astronomik CLS Clip in filter. For this shot, I used an Orion ST80 at prime focus on a Sky Watcher Star Adventurer. I did around 80 frames at 45 seconds, but it was a little windy and I was only able to keep 65 of them. I took 15 dark frames right after the lights. There was no cloud cover, transparency and seeing were both above average in my area. I don't understand why I can't see more in this shot. I think there are 2 possibilities, either I am not able to pull enough out of the image in Photoshop or my frames should be longer than 45 seconds. I know the general rule of thumb is over an hour of integration, but I should be able to see more than this at around 48 minutes. Can anyone shed some light on this please? If needed I can upload the original TIFF file from DSS. Thank you!

(I know about the distortion in the corners, I was excited to see what I could pull from the image and didn't bother with fixing it)


Edited by Likwid

Share this post

Link to post
Share on other sites

Hi Likwid.
I had a quick look in PS and just doing some basic stretching using just levels in photoshop it seems like you do see some nebulosity.

I made no attempts to keep the star size under control here, was just looking in 3s to see what was there.
If you look at the histogram of your posted image, all the information is in a tiny region on the left. You need to 'zoom in' to that region to see the range of light you have captured.

If that makes sense.
I'm sure someone else here will give you a better explanation but just a quick 'don't lose hope' it's not so bad :) GJ!



  • Like 2

Share this post

Link to post
Share on other sites

That makes sense! Thanks! I was hoping it was something that I wasn't doing correctly in post. Now I guess I have to watch a bunch of videos to learn more about editing!

Share this post

Link to post
Share on other sites

Can you convert one of the raw subs to a jpeg and post it (no editing)? Also, what ISO was used for the 45 sec exposures? These will help with a response.

Share this post

Link to post
Share on other sites

Hello bobro, here is one of the subs. 45 seconds, 800 ISO, unedited and straight from BackyardEOS output. Thanks!


Share this post

Link to post
Share on other sites

There might be more there than you think, what you need to do is post the raw stack (either a 16bit fits or tiff format), then someone can have a go at getting the most out if it.

Share this post

Link to post
Share on other sites

Your capture of a single sub is what would be expected for 45 secs. A rough stretch (no colour , saturation change) gives that attached image.

To give better colour in a DSS stacked image, set saturation to about 20% and align the RGB as shown in the attached screen captures. That will give an image with colour that is not dark. Not everyone does it this way as it depends on how images are subsequently processed.




Edited by bobro
  • Like 1

Share this post

Link to post
Share on other sites

I would try longer exposures.

If you do lots of shorter exposures it will reduce the noise and improve definition when stacked, but if you have insufficient data in each sub, stacking will not bring out something that's not there in the first place.

Share this post

Link to post
Share on other sites

Oh wow, thanks for the info and the settings bobro! Do I have to do that in DSS or can I do it in Photoshop? Thanks Starwiz, unfortunately it was a little windy and I was already pushing it with 45 second exposures. I really have to upgrade my Star Adventurer. So I did a re-edit and here is what I have so far, it looks much better than the original but I am going to keep playing with settings and see if I can do any better.

Pleiades resize.jpg

  • Like 2

Share this post

Link to post
Share on other sites
8 hours ago, Likwid said:

Do I have to do that in DSS or can I do it in Photoshop?

In principle you can do it either way. I use GIMP and find it easiest to do the colour corrections in DSS.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By The-MathMog
      Hey there.

      I am curious, as to what media or software you guys are using, in terms of knowing when certain alignments, conjunctions or events happen?

      I actually had a clear sky, a couple of days ago, when the conjunction of Venus and the Pleiades happened, but I didn't know until the day after. I even thought: "what a nice clear sky, but naaah, the moon is way too bright tonight" (I mostly shoot galaxies these days).
      So I am actually a bit bummed at missing that.

      So, what good sources are you guys using? I am mostly using stellarium, reading a bit on the forum here, and looking into SkySafari Pro (will that give any clues?). Or is it simply by chance figuring it out 😅

      Thanks in advance.
    • By frolao
      The Pleiades showing different temperatures in a super unfocused image (by accident). Only after looking better to this I noticed all brightest stars are there. Love it!
      Stars info using SkySafary6
      AVX SW80ED 700D 19s ISO12800, both images


    • By mikeyscope
      Just a quick cropped image of the Venus/Pleiades conjunction with Hyades looking on by moonlight from last night.
      Pentax K5 / Pentax 12-24mm lens / 1.4x rear converter / Exp. 30secs @f10 / iso 500
      Ioptron tracker at siderial.

    • By Photosbykev
      30+ exposures between 1 and 60 seconds with an ASI533MC_Pro and WO61 refractor. The huge dynamic range makes this a real challenge lol

    • By Ken Mitchell
      Hi all,
      For a long time I wanted to shoot this frame, probably from the early days of my astrophotography adventure.
      Finally after all these years I managed to get a decent result of the 'stuff' between these two beautiful nebulae. Fairly happy with the image but always looking for improvement.
      I hope one day to redo this all with a mono camera and filters. 
      Apart from NGC1499 , M45 and the Baby Eagle Nebula no idea what else is in the picture. If you happen to have an idea feel free to educate me.
      Some info on image and capturing:
      Widefield Pleiades to California.
      Taken over 2 nights with a total of 11hrs 25min integration.  
      With a stock Nikon d610 and Nikkor 85mm 1.8 objective.
      Tracking was done with the Skywatcher Star Adventurer.
      Lights and all calibrations frames were stacked in DSS.
      Processing was done in Adobe Photoshop CC using Adobe Raw, GradientXterminator plugin, HLVG plugin, Nik software plugins and Photokemi action set.

  • Create New...

Important Information

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