Handling solar flats in Autostakkert

[Notty]

Hi, can anyone help me with the workflow in AS when incorporating flats? I took one today, centre of the disc and defocussed and stacked it in AS. I've got some questions.

1. Firstly, I assumed there was nothing particularly special settings wise to stack a flat

2. Secondly, am I right that I have to analyse and set my align points on the avi to be stacked and only then select the "add master flat" option?

3. Does anyone know of a way of automating this in AS such that if you select a number of subs to be stacked that it will automatically add the master flat?

4. My stacked flat has several "stacking artefacts" I believe we call them, I.e black roughness around the edges; a bit like the bits we have from the stacked subs that we normally crop out before we try and create a mosaic. Is this normal, and if so will I invalidate the flat if I crop them out?

If anyone can help with this I will be extremely grateful..

Thanks

Andy

[michael.h.f.wilkinson]

I set my master flat before anything else in AS!2. The flat has to be applied individually to each frame, after all.  My approach seems to work well

Shading and dust bunnies are gone.

Note that I always create the flats with Registax, and tweak them in ImageJ. I have not worked out how to create a flat in AS!2

[Ibbo!]

open your flat avi (i use surface)

click image cali

create mater flat

save as tif

let it run

open avi's to stack

click image cali and select use master flat

and off you go

[Notty]

Ah I didn't realise I had to explicitly create it as a master flat, that's really helpful thank you

[Notty]

It turns out I don't have a "create master flat" on my image calibratin menu, I only have load Master dark and flat and create master frame.  I'm on the latest beta 2.3.0.21 which version do you have?

[Zakalwe]

It turns out I don't have a "create master flat" on my image calibratin menu, I only have load Master dark and flat and create master frame.  I'm on the latest beta 2.3.0.21 which version do you have?

Use "Create Master Frame". just drag and drop your avi into AS!2 and select "Create Master Frame". Then name it in the File Save As window that pops up

I use a variant of this method:

http://www.schursastrophotography.com/solar/Articles/solararticle5.html

When I do flats (which isn't that often) I use a piece of cling-film pulled over the front objective. You will have to wind the exposure and gain up to get the histogram to move, but this seems to give a better result than a de-focused image.

[Pete Presland]

What an excellent tutorial, looking forward to some clear skies to give it a go

[Ibbo!]

my bad - sorry

it was as though it was late either

[Notty]

Thank you one and all... and sorry I should probably have asked this in the Software section... where I am about to ask my next one!