SingAstro

cataclysm · Post by **cataclysm** » Tue Jul 10, 2007 10:03 am

Just processed this picture taken on 7 July with the cooled camera set up. The result is more than i can ask for. I was able to pushed to 1600 ISO for 8 minutes sub with tolerable heat signatures. The significant improvement was it require shoter overall integration time to yield the same results.

Genesis SDF
Canon 350D (Mod)
3x8minutes ISO1600 with Halpha filter
10x5minutes ISO1600 with OIII filter
Dark,Flat,Bias calibrated with ImagesPlus

raychan · Post by **raychan** » Tue Jul 10, 2007 10:40 am

Wow......at 1600 ISO, this is great. You can hardly see any noise at this size unless you blow it up to full res.

Think you should patent your camera cooler !!

Two thumbs up !!

Post by **weixing** » Tue Jul 10, 2007 10:49 am

Hi,
Nice image...

Have a nice day.

Meng Lee · Post by **Meng Lee** » Tue Jul 10, 2007 2:03 pm

Erm, don't set the black point too low. Some data is lost. Try making the dim regions of the nebula come out by using curves, or DDP or SMI.

If you set the low black point to get rid of the skyglow or gradient, then you lose the data on the dim parts of the nebula. Use a flat frame then remove the gradient.

I can see the picture has a great deal of information in it, but clipped.

cataclysm · Post by **cataclysm** » Tue Jul 10, 2007 11:42 pm

I can see the picture has a great deal of information in it, but clipped.

Thanks Meng Lee, noted.

Post by **rcj** » Mon Aug 06, 2007 5:10 pm

sorry for coming in late with this. it is definitely a marked improvement in performance for the additional cooling. Longer exposures per sub exposure is definitely the way to go where conditions allow. Notice that you took OIII as well. How did u integrate the OIII into the final result?

Cheers to a great image!

cataclysm · Post by **cataclysm** » Mon Aug 06, 2007 6:17 pm

Notice that you took OIII as well. How did u integrate the OIII into the final result?

Hi Remus, the combination is HaHaOIII, Ha as luminance, Ha is used again as red channel, OIII as blue green Channel. Still experimenting with the right mix. as you can see, the colour is a bit off.

Post by **rcj** » Mon Aug 06, 2007 7:27 pm

It is a bit but not too much. You might like to experiment with the following combination also:

R: Ha
B: OIII
G: OIII multiply with Ha

You can do this in photoshop. After that, one can fine tune the result via Hue/Saturation slider to suit your taste.

SingAstro

M17

M17