Darks' Bias' Flats' Frames

[Taff]

Hi' Can you use Darks' Bias' Flats' Frames again for another night by keeping them, or won't they be any good Thanks.Mark

[Hawklord]

Darks - yes, as long as they are at the same temperature as your lights, or as close as you can get.

Bias - yes

Flats - not easy. Flats essentially are the blueprint of the total imaging train, so focus and orientation needs to be the same for each 'lights' session and no new defects are encountered (extra dust etc).

Elsewhere there are other good discussions about these. There is also a great piece in March S&T on flats.

[RobH]

Hello Taff.

There's a lot of info about calibration frames on my website, with examples etc, plus what can go wrong!

Middlehill Observatory, Dorset UK. The Astrophotography of Rob Hodgkinson.

Have a look at the 'primers and tutorials' section.

Cheers

Rob

[Taff]

Hi' Thanks for your help.Mark

[yesyes]

Very good prime there, Rob.

What I'm still not sure about: Bias and darks, do you take them through the scope but with the front cover over the aperture? Or with the camera removed and the body cap on?

[martin_h]

Very good prime there, Rob.

What I'm still not sure about: Bias and darks, do you take them through the scope but with the front cover over the aperture? Or with the camera removed and the body cap on?

Either whatever suits you, as long as the darks are at the same temperature as the lights.

[yesyes]

Well, it'd be a lot easier if I could leave the camera mounted to the focuser and therefore avoid rotating it for the next session. So basically dark is dark, as long as the scope is light-tight, it shouldn't make a difference?

[jgs001]

As I use my camera during the day, I remove it from the scope, and set it up with the normal lens on taking darks, whilst I drag everything else in... I'm working on a library of darks, but so far, I've got away with the one set for this winter... as it's always been bitingly cold (that is a temperature ), well at lesat similar temperatures, when it's been clear...

[George]

Well, it'd be a lot easier if I could leave the camera mounted to the focuser and therefore avoid rotating it for the next session. So basically dark is dark, as long as the scope is light-tight, it shouldn't make a difference?

I do my darks after any imaging session after I have locked averything down and the obsy is light tight. I just initiate everything via VNC, if the darks session looks to spill into daylight hours I'll throw a light blanket over the imaging train & camera in case of light leaks......works for me.

[martin_h]

Well, it'd be a lot easier if I could leave the camera mounted to the focuser and therefore avoid rotating it for the next session. So basically dark is dark, as long as the scope is light-tight, it shouldn't make a difference?

Thats right.

[yesyes]

thanks !! ;-)