Quote:
Originally Posted by Atmos
You've got some really nice detail in the centre so those 30s subs look to be working quite well. Also look at what Kevin (cometcatcher) is doing with his DSLR, he spent years photographing out of his kitchen window with a HEQ5 and 8" newt  Hundreds of 30s unguided exposures.
As has been mentioned, the amount of calibration needed can differ. On a bright target with longer focal length I could probably get away without darks on my DSLR but when stretching to show up the fainter stuff I get quite a bit of background banding, this is what the darks remove. Some cameras show this up more than others.
As for flats, if your sensor is clean (not a lot of dust motes) then flats are mostly just for fixing vignetting which purely allows you to accurately stretch out signal in the corners of your frame. If you don't mind that it isn't technically accurate in the corners then it isn't too bad 
To sum it all up, if you're not wanting to push your system to the edge of its limits, extracting every whisper of faint signal and having everything as technically accurate as possible, then yes, you can get away without any calibration
To give an actual example, both of these images have been processed in exactly the same one. One is fully calibrated and the other isn't. After stacking both have had their black point set, colour calibrated, stretched and hit with the same curves/saturation change.
I am lucky in that I only get 3-4% vignetting in the corner of my images so it isn't noticable. it is also a high enough signal area where the banding that I mentioned earlier is buried until strong SNR.
These are both 36x180s shots at ISO800 taken 5 days ago.
So in answer to your original "question", yes, you can still do a lot without any calibration whatsoever I do dither ~3 pixels between each frame though which really helps mitigate some issues that comes from not calibrating. |
Hmmm... Not a lot of difference there! Thanks for the demo.
Having recently changed careers - and having two small girls under 4 - I'm pretty time poor, so currently enjoying the quick easy results of stacking short exposures. Such an approach lends itself nicely to my camera too. I'll get back to the more challenging targets eventually and will likely get back into proper calibration.