Panoramic: M20 - M8 - NGC6544 - NGC6553

whzzz28 (Nathan) · #1 20-05-2012, 08:25 PM

Thought id try this out.
As expected - didn't turn out the best, but the result is OK.
Stars are a bit bloated due to processing and some of the seems of the image are visible if you look hard enough.

The hardest part was equalizing the sky glow over the three images. Easy enough to make a layer mask for each image and specifically set the RGB levels. Looks good until you combine them and start playing around with levels/curves

First time using Photoshop for processing, happy enough with how it turned out.

Anyhow:
Three photos taken over a week joined together. M20 was taken with different exposure times so it has a bit more of a star field compared to the others. This is as they appear in the sky (rotated FOV for picture purposes of course).
In order from left to right is:

M20 (Trifid Nebula)
M8 (Lagoon Nebula)
NGC6544 (globular cluster)
NGC6553 (globular cluster)

100% (3.6mb):
http://core-au.net/astro/m8/pano-100.jpg

50% (1.1mb):
http://core-au.net/astro/m8/pano-50.jpg

Comments regarding processing are most welcome!

dannat (Daniel) · #2 20-05-2012, 08:36 PM

overall he image is very good -as you state the gradient in the mosaic is a bit off but you have captured the nebulosity well, the GC's on the right are a bit mustard coloured? not are why

whzzz28 (Nathan) · #3 21-05-2012, 06:22 PM

I had an objective look at the image today in a bit more detail.

Actually i'm rather disappointed in it. Star trails are clearly visible and stars fuzzy (dew problems mostly).
The idea was good but probably not possible without very dark skies to prevent the variance in glow between images.

Think ill take a break for awhile until the dew heaters arrive in a few weeks and i can get the new scope out.
HOPEFULLY that will give much more pinpoint stars.