M 1 - Crab Nebula

[Jim McMillan]

A run of good nights allows for one more.

L=47 x 10 min
RGB = 20 x 10 min

The star spikes are added with software. I think it helps the image a little.

Imaging without the moon makes such a difference with respect to processing!!

Jim

[pedrocanel]

A very good one indeed. Nice contrast. Just as a personal taste opinion, have you tried to make a "sharper" version of it? I mean this one is absolutely stunning but... could it get better ? Keep it up

[Jim McMillan]

Thanks, Jose. My seeing isn't so great in Cleveland, OH; the luminance layer already went through deconvolution. Then, I applied an unsharp mask to the nebula itself.

Based on your suggestion, I did a little more unsharp mask, but I can't push it much more without the stars starting to look unnatural. I think this version is subtlely better.

I also note a bit of a green cast to the .jpg which isn't in the .tiff. Oh well.

Regards,

Jim

[Dick Berg]

Jim,

I agree with Jose, this is stunning. You've found the recipe - it's time to get a TV show on the Science Channel "Cooking with the Cosmos". In addition to the long data collection, how much time does it take you to put the pieces together and produce the final product? Just curious.

[Jim McMillan]

Hi Dick. Thanks for your comments.

The process doesn't take as long as you might think. It goes like this:

1) Acquire the data including flats at the required PA
2) Calibrate (or reduce, whichever term you like)
3) Auto gradient removal in MaxIm (if the moon's out - only partially effective, but better than nothing)
4) Bloom removal (NewAstro DeBloomer plug-in)
5) Dead pixel removal
6) Hot pixel removal
7) Align all the images to one luminance image
8) Combine L,R,G,B using SigmaBeta 11 (Ray Gralak)
9) Deconvolve, Digital Development Luminance (CCDStack)
10) RGB combine (MaxIm)
11) Digital Development of RGB image - very gently (MaxIm); sometimes increase saturation
12) RGB split (MaxIm)
13) LRGB combine split RGB with L (MaxIm)
14) Save as .tiff
15) Use "Astronomy Tools" in PhotoShop Elements - that usually means:

a) levels
b) soft gradient removal
c) increase star colors
d) remove color blotching
e) remove deep sky noise
f) add star spikes

Probably getting all the images processed/combined into their separate L,R,G,B might take 20 min. The LRGB combine to finished product also takes about 20 min. I really don't mess too much beyond the steps I've outlined.

I will say that if you use any of the PhotoShop versions to do anything, Astronomy Tools is a real gem. It does a lot of the hard stuff - things I don't even know how to do - in just a few easy steps. Highly recommended.

Regards,

Jim

[Dick Berg]

Thanks, Jim.

I would have said it this way:

Go to the store and get all the ingredients (steps 1&2)
Pour them in a large bowl, making sure to get out the lumps and other foreign matter (steps 3-6)
Mix gently for 20 minutes, adding additional ingredients as required (steps 7-10)
Add some MSG to enhance the flavor (step 11)
Pour into a cupcake pan and bake for 20 minutes (steps 12-14)
Remove from the oven and let cool; then dust with powder sugar, sprinkles and bling (steps a-f)


I have the Astronomy Tools and Photoshop v6, but I have yet to really explore how to make them work for me. Your recipe is a great outline for the process.

[pedrocanel]

That's funny, I get just abut the same result but I do cook differently ... Oh Well.. I guess it's teh European side of cooking

[John K]

I'd suggest using smart sharpen on a masked layer, then use a brush to reveal the areas where sharpening is desired. However this one is great as-is!