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graham.hobart
23-08-2011, 08:15 PM
Yesterday I managed to get nearly an hour of lights around antares. 30 second exposures, 5 second intervals with 450D. I have noticed a red glow on the images- is this amp glow? (ISO 800)
Should I allow longer for the camera to cool down between images?
I am using a battery so maybe it's thermal noise from the battery.
NB the actual frame time was longer with the pause for APT to download the frame, but I suppose the camera was still working when the software said "busy" (about 20-30 secs per frame)
Will post a pic so you know what I mean , but not now as in the garden waiting for the clouds to dissipate again
Graham. :confused2:

multiweb
23-08-2011, 08:41 PM
There is a Ha region around the bottom star after the small cluster so maybe you've picked that up.

graham.hobart
23-08-2011, 09:24 PM
Could be, here it is.....it's certainly near the little cluster..
Graham

graham.hobart
23-08-2011, 09:49 PM
I just whacked the DSS frames through StarTools then to see what happened- boosted the background in Nebulosity- does this mean I was shooting in the wrong place to get some of the ophicius cloud complex or that I just haven't got enough light data?
graham

DavidTrap
23-08-2011, 10:02 PM
Assuming you're not using in camera noise reduction, take some dark frames and compare. Amp glow will show up on dark frames, nebulosity won't.

DT

graham.hobart
23-08-2011, 11:41 PM
This is a new (second hand) camera to me (450D) I took darks and didn't notice any thing so I assume it's nebulosity
I don't know how to do in camera noise reduction.
The frames were biased with flats/darks/ dark flats.
graham

ZeroID
24-08-2011, 12:37 PM
Amp noise normally shows up as a fan of fading red from one corner, the one nearest the electronics from examples I've seen previously. Yours looks more like nebulosity. Try the Darks solution above to confirm.