Wide Angle Orion - Red/enhanced version

[CometGuy]

This is a reworked version of a shot of Orion I took to show how a modified 300D performs for nebula work (for the guys buying the Hutech 5D - more than one on this forum!). The image is problably not to everyone's taste, but it is my attempt to accentuate the nebula regions whilst try to maintain star colours.

I am pretty pleased with the detail considering it was made in a suburban sky on warm summer night, unfiltered and with 36 minutes total exposure

The 50% version (about 400KB) is at:

http://www.pbase.com/terrylovejoy/im...98502/original

Terry

[atalas]

Awesome shot Terry ! I love It ,has great deatail an excellent star colours and nice round stars .

[avandonk]

I'll send you the Raw frames and you can process them.You have to explain your protocol for processing images. Very nice. I still have a lot to learn!

Bert

[CometGuy]

Bert,

Absolutely send your raw frames (I don't care if they are 10-15MB as I use webmail + high speed internet).

The processing goes like this:

1. 12 raw frames loaded into IRIS (I am using version 5.2). Multiply intensity values 5x as this prevents posterisation of faint details in later processing.
2. Create a matched dark frame from my dark library - this is a process too long to explain here as it really needs a webpage to explain.
3. Calibrate frames with dark frame then remove hotpixels using IRIS 'cosmetic' correction.
4. Flat field calibration.
5. Batch Convert raw images to colour.
6. Generate a mask image that blocks out M42 and bright stars . Apply gradient removal tool in IRIS (subsky settings 6,3) using this mask to each frame.
7. Normalise sky background to 100 for each frame.
8. Register and add images using adaptive add and save a final image. There is a normalise setting that prevents saturation of pixels in IRIS, which I use.
9. Repeat step 6 but using a mask created from final image to ensure background gradients have been removed completely. This takes a little bit of effort to do in light polluted skies.
10. Separate out the red channel, set the background level to 0, then clip just above this level (but high enough to preserve faint nebula). Add this back into the red channel of the final image. This doubles the apparent brightness of the faint nebulosity, without drastically effecting other details.
11. Using Dynamic stretching in IRIS as well as adjust whitebalance and saturation to taste. Export to bmp or tif format
12. Resize and convert to jpg in Adobe Elements. Sometimes I do other work in Adobe Photoshop elements as well, but in the above case no other processing was done.

Terry

[avandonk]

Great stuff Terry will let you play with the first images. I have high speed internet can work something out

Bert