Home · Register · Software · Software · Join Upload & Sell

Moderated by: Fred Miranda
Username  

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Canon Forum | Join Upload & Sell

  

Milky Way and Andromeda
  
 
cameron12x
Offline
• • • •
Upload & Sell: On
p.1 #1 · p.1 #1 · Milky Way and Andromeda


What's the difference between a 24mm wide-angle lens and a moderate 200mm telephoto lens?

Milky Way and Andromeda.

The skies were pretty clear last night/this morning so I decided to try out some new lenses. Lots of vignetting with the wide-angle lens and some apparent image blur (due to the exposure length) noted in the Andromeda image.

Not bad for less than 3 minutes total exposure for Andromeda.











Edited on Oct 23, 2017 at 01:49 PM · View previous versions



Oct 18, 2017 at 02:11 PM
dgdg
Offline
• • • • •
Upload & Sell: Off
p.1 #2 · p.1 #2 · Milky Way and Andromeda


Uncropped very nice.
What gear were you using?
Did you catch the astro bug?!?!



Oct 18, 2017 at 03:17 PM
cameron12x
Offline
• • • •
Upload & Sell: On
p.1 #3 · p.1 #3 · Milky Way and Andromeda


Thanks... yes, have caught the " astrobug."

For last night, Canon 6D body and two lenses: Canon 200mm f/2.8L and Rokinon 24mm f/1.4.

The shot of Andromeda is cropped and was created from (76) individual 2-second exposures stacked in DSS.



Oct 18, 2017 at 03:27 PM
Herb
Offline
• • • •
Upload & Sell: On
p.1 #4 · p.1 #4 · Milky Way and Andromeda


I think I can see someone waving in your photo...in a galaxy far far away......


Oct 18, 2017 at 09:31 PM
 

Search in Used Dept. 



cameron12x
Offline
• • • •
Upload & Sell: On
p.1 #5 · p.1 #5 · Milky Way and Andromeda


The next step in the learning curve is to use an entry-level equatorial mount (I have a CG-5) so that I can get longer exposures.


Oct 19, 2017 at 06:08 PM
Pixel Perfect
Offline
• • • • • • •
Upload & Sell: On
p.1 #6 · p.1 #6 · Milky Way and Andromeda


Great result Cameron. Yeah 200mm barely allows a 2s exposure without tracking and that's for a 7 pixel blur tolerance. Although it's Mac only, the software called Starry Landscape Stacker, apparently runs rings around DSS.

Checkout this very good site:
https://www.lonelyspeck.com/

Also has an advanced exposure calculator.



Oct 23, 2017 at 04:40 AM
cameron12x
Offline
• • • •
Upload & Sell: On
p.1 #7 · p.1 #7 · Milky Way and Andromeda


Pixel Perfect wrote:
Great result Cameron. Yeah 200mm barely allows a 2s exposure without tracking and that's for a 7 pixel blur tolerance. Although it's Mac only, the software called Starry Landscape Stacker, apparently runs rings around DSS.

Checkout this very good site:
https://www.lonelyspeck.com/

Also has an advanced exposure calculator.

Thanks, it's not "Pixel Perfect" (), but it's marginally good enough--given the equipment I used. I'd love to have big fat pixels with the dynamic range we have in modern sensors. I suppose that means buying a dedicated astrophotography camera, though.

Due to the perceptible image blur in this image, I did later shoot with a ONE second exposure length, but the S/N ratio suffered (as the author at LonelySpeck also points out). The detail was far better with the second image, but there simply wasn't enough "signal" to make it any better aesthetically--even with 4 times the overall exposure (742 frames).

That said, the "seeing" conditions on that night weren't nearly as good, and that input variable trumps EVERYTHING else in astrophotography. I may try again with a ONE second exposure under optimum "seeing" conditions.

That's too bad that Starry Landscape Stacker is only available for the Mac. DSS is very good, but it also has some quirks that I don't like. LonelySpeck is an excellent site. Thanks for sharing.



Oct 23, 2017 at 01:43 PM
cameron12x
Offline
• • • •
Upload & Sell: On
p.1 #8 · p.1 #8 · Milky Way and Andromeda


Image of 742 stacked frames (ONE second) exposure below. Halving the shutter speed produced much better rounded stars.

Despite much more integration (exposure) time, the "seeing" conditions were not nearly as good for this image they were for the first one.

So, while there is more detail with this image (due to a faster shutter speed), the noise floor was much higher, negatively affecting DR and the overall S/N ratio.

Working on the color now. Stretching the RGB curves is very challenging when working with poor DR and a very narrow S/N ratio.







Oct 23, 2017 at 02:15 PM







FM Forums | Canon Forum | Join Upload & Sell

    
 

You are not logged in. Login or Register

Username     Reset password