Victory!

[pipnina]

It was back in february (I think) when I took this stack of images from my back garden. But since I've been working on improving my image editing I wanted to revisit an older image before another attempt this winter. Here's what I got:

http://i.imgur.com/J3Iozs3.jpg< 32-bit TIFF from DSS editied in Blender (only thing on my computer that can open 32-bit images)

http://i.imgur.com/8vYFEoU.jpg<16-bit TIFF from DSS editied in Paint.NET (it does look to be a little little bit more posterised?)

Considering this is less than 10 mins of data from urban skies I'm very happy with this result, I managed to pull a bit more data from M42 and even managed to get a few pixels of the flame nebula! (or at least it looks like it anyway...)

I'd actually like to try and build on this image when Orion comes round again, so I'd like to ask some advice for when I go to stack the images:

• When it comes to DSS, how important is my choice of stacking method? I seem to remember this image used median although some of my images have used Kappa-sigma
• Since I'm unmotorised, How often should I re-align the lens (being used at 35mm) with the middle of orion? The edge of the lens suffers from optical vignetting and distortion.
• Could my difficulty adjusting the white-balance of this image be in any way linked to lack of data or is it just me being useless? (I can't stop this image being purple!)

Cheers guys!

    ~pip

[ollypenrice]

It's not unusual to end up with colour out of balance in the background sky, nor are brightness and colour gradients unusual. To understand them better it's as well to know what the present colour balance really is. To do this you need a graphics package which can sample small parts of the image, around 5x5 pixels or so. You can do this in Photoshop (colour sample eyedropper). Doubtless lots of packages will offer this facility. Personally I aim for neutrality, so R, G and B at the same level and I like 23 as a level, so I want to see 23/23/23 in RGB. 

Olly

[Scott]

It's not unusual to end up with colour out of balance in the background sky, nor are brightness and colour gradients unusual. To understand them better it's as well to know what the present colour balance really is. To do this you need a graphics package which can sample small parts of the image, around 5x5 pixels or so. You can do this in Photoshop (colour sample eyedropper). Doubtless lots of packages will offer this facility. Personally I aim for neutrality, so R, G and B at the same level and I like 23 as a level, so I want to see 23/23/23 in RGB. 

Olly

Just wondering Olly, do you think 23/23/23 is attainable from suburban sites or is it just what works from your dark site?  obviously personal taste plays a big part, but I seem to recall reading a guide where the author used nearer 30/30/30.

I ask not to be awkward but because I'm clueless as to the answer

[pipnina]

It's not unusual to end up with colour out of balance in the background sky, nor are brightness and colour gradients unusual. To understand them better it's as well to know what the present colour balance really is. To do this you need a graphics package which can sample small parts of the image, around 5x5 pixels or so. You can do this in Photoshop (colour sample eyedropper). Doubtless lots of packages will offer this facility. Personally I aim for neutrality, so R, G and B at the same level and I like 23 as a level, so I want to see 23/23/23 in RGB. 

Olly

I think I found the tool you were talking about. I can't use it while i'm messing with the histogram so I have to do smaller changes however it did yeild a better result than I had before:

http://i.imgur.com/VRVg1wQ.jpgIt still changes from being redish in the dark bits to greeny in the brighter bits, but it's much more neutral than before.

Thanks!