Wide Field Image near Sagittarius

Chris Southby (Chris) · #1 14-09-2009, 02:34 PM

Hi all
This widefield image was taken just NW of Sagittarius at Narooma, this is my better first attempts at astro-imaging.
It was taken with an unmodified Canon 350D, using 55mm focal length at f4.5. The camera was mounted on EQ5 goto mount(not polar aligned).
There were 8 x 60sec lights frames, 6 darks, 3 flats and 3 dark flats.
The images were stacked in DSS and processed in Raw Therapee and Paintshop Pro.
Any tips on colour enhancement or other processing issues would be welcome.
And yes I know polar alignment would help a lot but time was short and I was setting up away from home.

Cheers
Chris

tlgerdes (Trevor) · #2 14-09-2009, 05:46 PM

Hi Chris,

Looks like you have set your black point too high, the historgram for the picture shows a hard cut off in the black, which means you have somehow cut out lots of valuable data.

Your histogram is on the left (Histogram-1), what you should have is closer to the right (Histogram-2).

Your tracking though looks fine, next time push it for more exposure time.

Keep at it.

Chris Southby (Chris) · #3 14-09-2009, 07:00 PM

Thanks Trevor
Here is the original. I kind of liked the daker more contrasty image.

Cheers
Chris

[1ponders] (Paul) · #4 14-09-2009, 07:05 PM

Chris, did you shoot in jpeg or Raw? What ISO and was your camera set at? What did you use to resize the image for uploading to the site? It is very heavily pixelated.

Chris Southby (Chris) · #5 14-09-2009, 07:43 PM

Yep the second image looks horrible will try to get a better one

I didn't notice it before

tlgerdes (Trevor) · #6 14-09-2009, 08:16 PM

Hi Chris,

I understand what you mean, I like some darkness in my night sky, but widefields usually end up capturing quite a bit if light and colour that the naked eye cant see. Also the night sky isnt black, it is a multitude of dark greys and other colours, again setting the black point correctly will let you capture all the subtle differences.

Chris Southby (Chris) · #7 14-09-2009, 09:14 PM

Hope this image comes over properly

Images were shot in RAW at 800ISO

[1ponders] (Paul) · #8 15-09-2009, 07:29 AM

That looks muck better Chris. jjjnettie did a similar shot recently and posted it here.
http://www.iceinspace.com.au/forum/a...se.php?a=63917
and matt posted an almost identical shot to yours here
http://www.iceinspace.com.au/forum/a...se.php?a=63960

tlgerdes (Trevor) · #9 15-09-2009, 07:29 AM

That image is heaps better than the first. You have more depth of colour and texture. So your capture method is spot on, just need maybe work on the processing side a little more.

Here is a repro i did this morning, adjusted levels, colour balance and saturation.

Chris Southby (Chris) · #10 15-09-2009, 08:27 AM

Thanks Trevor
Will keep at it. Its bloody addicitve.

Cheers

Chris

tlgerdes (Trevor) · #11 15-09-2009, 09:27 AM

Remember, with processing, it is your interpretation of what you want to see. There is no right and wrong. It is your artwork.

Octane (Humayun) · #12 29-09-2009, 11:53 PM

Chris,

Woohoo, congrats on your first images! Onwards and upwards from here on end.

You'll find no end of help on here.

Regards,
Humayun