11 replies to this topic

[Tonk]

Hummm - I set out to capture 100 x 3 minutes images of M37

After clouds saw off 26 frames, I visually inspected the rest. 32 had trailed or dumbelled stars - it was windy. 42 frames left. Lets focus grade them in Images Plus (always a wise move) - 13 more rejected. Ok 29 good subs left (poorest yield I've had in a long time!!!!) ... this is the result

29 x 3 minutes ISO 800 - usual convert to TIFF, calibrate dark/flat, DDP, curves/levels iterative stretch, iterative colour saturation, some modest noise reduction. .. Oh I had wire cross hairs on as well - cripes - this is a 30% quality JPEG - it suffers - not had a good time with this one :o

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[Corn]

Looks nice from here.

[s58y]

Very nice. I guess being picky when rejecting frames helps out with the pinpoint star images across the frame.

[Shadowalker]

M37 is fantastic. My favorite in Auriga. You did good.

[Dubboy]

I still like it!!

[ralon73]

Hi Tonk,

Very nice looking image !

there is one thing that puzzles me though.......why taking 100 frames of 3 minutes of a starcluster ??

I could imagine taking that much frames of a nebula in order to get a good S/N ratio and bring out some faint details, but a star cluster ??

Regards,

Raimond.

[Rammysherriff]

iterative colour saturation - that's a new one to me Tony; is there a quick explanation?

[Tonk]

there is one thing that puzzles me though.......why taking 100 frames of 3 minutes of a starcluster ??

Easy - 10 fold noise reduction - good clean signal and its possible to do nice things with colour enhancements - without getting random colours from noise. Its all about noise reduction. I've done the same procedure with shooting the full moon to pick out and enhance minsicule colour info

see - http://tinyurl.com/yc4xat - thats 100 frames combined

iterative colour saturation - that's a new one to me Tony; is there a quick explanation?

I've been using this method for a couple of years now - got it from S+T in artical on how to enhance moon colours.

1) Use a hue/saturation layer in Photoshop. Shove up saturation until the colours suddenly go "haywire" - you will know what I mean when you try it. Note the value. Now back off the value to just less than half.
2) Add another hue/sat layer with sat set at half the previous
3) Repeat to taste

The real trick is masking out the background black bits - otherwise you start seeing nasty chromatic noise everywhere. I have a method using the colour range picker (under PS selection menu) to pick out only the bright and medium bright stars for this treatment

[jmcdonald]

Gorgeous. I usually don't like added diffraction spikes but I guess it's the computer-generated ones that look bad. These look nice.

[Galaxy001]

Very pretty! Colors are really nice.

[atalas]

Nice cluster Tonk.

[AuroraSeeker]

Nice Tonk