Calibration frames versus extra subs for imaging with camera only?

[ianpwilliams]

When doing astrophotography under dark skies with just a camera (no telescope) and with time being a factor, would I be better off devoting time to subs/darks/flats/bias (doing bias indoors afterwards), or would I be better off just taking as many subs as possible? It'll be a rare chance for me to get under dark skies (assuming there's a clear night), so I'd like to know which option is likely to be the most productive.

[MattJenko]

Light, lights and more lights. All darks/bias can be done after and flats also, if you are careful with the camera/lens and don't use sensor cleaning features and knock about any dust too much.

[Rush]

To be honest, for short time subs dont bother about cal.frames.

But thats me. take at least 30 or more within 600 or 500 rule. (During your initial sessions)

Do CC in PI  and regular processing. 100% You will be happy seeing ur results

Milkyway 30 frames @ 20 s with 1600 Iso (24 mm at  4.5) will get you something like this without cal.frames.

CS

Rush

[Alien 13]

As above you can concentrate on the lights, assuming its a DSLR then dark's are questionable, bias can be done anytime and you can get away with lens correction data for the flats perhaps taking one which you can use to get the dust delete data which can be stored in camera.

Alan

[ianpwilliams]

Wow that is one impressive photo! And yes it is a DSLR (Canon 1100D). I'm relieved to hear that lights are the way to go, because I can well imagine calibration frames eating up valuable time.

When you say "you can get away with lens correction data for the flats perhaps taking one which you can use to get the dust delete data which can be stored in camera", what would I do exactly? Would I take a single flat, and then get the camera to detect dust in that flat and store the data, and then have the camera apply that data to all of my lights?

 

 

[Alien 13]

Canon cameras have a dust delete data menu that tells you the process to follow to crate an internal file and can be turned on/off a similar menu exists for lens correction data (the camera will recognize supported lenses), these adjustments can be included in the RAW processing with something like DPP which comes free with the camera.

What I do though is use the lens correction data for distortion/vignetting and produce a single shot with the lens removed to capture the dust bunnies on the sensor (manual mode and shutter adjusted so not too bright) and manually subtract them in PS.

Alan

P.S The lens data is first registered to the camera in EOS utils.

 

[SteveNickolls]

I have started not taking dark frames as there is no way I can control the chip temperature during a session. You can most likely disable sensor cleaning on your camera (check the manual) and if you do not upset the optics you could take your flat frames (and bias frames) the following day at your leisure maximising your time for taking light frames while you can at the dark site.

Cheers,
Steve

[ianpwilliams]

Thanks everyone, I've decided that I'll take as many lights as possible, do bias at my leisure, and be very careful with the optics and hopefully do flats when back inside.

[happy-kat]

Great question, useful answers.