Solar imaging and flats

[tjensen]

This might sound like a silly question, but how do people take flats when using H-a scopes?

The only way I can think of to get a uniform white light that includes the entire imaging train is to start an AVI capture and then randomly move the telescope so the solar disk slides across the image. When the flat is created, this should give an even illumination.

Is there a better way?

Curiously,

[Ibbo!]

centre on the sun de-focus take an avi of about 300 frames stack and use this in registax

Does not work all the time but I've had a little success with this method when I remember to do it

anybody got any others

and why does the spell checker not understand English

Steve

[tjensen]

Thanks Steve.

I've never defocused my flats. Won't that change the pattern for the dust and vignetting and reduce the effectiveness of the flat?

Cheers

[Ibbo!]

seems to work for solar

I think it removes the gradient more than anything

give it a try

got the tip from pete lawerence

i do not alter for deep sky

Steve

[GreatAttractor]

For webcam & white light I defocus, works perfectly (at both F/8 and F/16).