Calibration Images and Colour

[E_ri_k (Erik)]

Hey guys, maybe a silly question, but.....Should you convert your calibration images to colour, when stacking CCD images? At the moment I am, and it seams to work.

Just wondering, because when I convert my Flats, the light portion is always blue?

Erik

[Tandum (Robin)]

This extract from the maxim help files seems to say you should debayer after you calibrate and before you align and stack.

[rcheshire (Rowland)]

Hi Erik. Do you mean convert 'calibrated' images to colour? Debayering is the step between calibration and registration.

[E_ri_k (Erik)]

What I mean is converting flats bias etc to colour, then stacking. I am capturing all data in maxim then stack in DSS. Havent figured out maxim that well yet. so I register all my colour converted images, (lights, dark,flat,bias) in DSS then stack. and then process in PS. If I process the same files in DSS without colour converting. Maxim doest convert the stacked image to colour very well. It works the way i am doing it. Just wondering if it is correct. It is a bit time consuming colour converting 100 images in maxim one by one.

[Peter.M]

Are you using a one shot colour camera or a monochrome and filters? Maxim will do pretty much anything you ask it too. From what you are saying I think you are using a monochrome ccd with filters and you are using maxim to make a colour frame for each set of subexposures?

like making red green and blue 1 into RGB1, doing this with each subframe set and then stacking the RGB subframes?

so in DSS you stack this?

RGB1
RGB2
RGB3
ect ect


I am using DSS and maxim and I stack all of the filters frames together including any calibration frames and then take the calibrated stacked frames into maxim to do my RGB combine.

[E_ri_k (Erik)]

Sorry. I should have said it is a OSC camera. It downloads the image in mono then i have to convert.

[multiweb (Marc)]

Originally Posted by E_ri_k

Sorry. I should have said it is a OSC camera. It downloads the image in mono then i have to convert.

Calibration is the very first thing you should do. Dark subtraction, flat fielding. Then debayer, align, normalise and data rejection. In that order. So you don't debayer anything wether it's light subs or calibration frames. You do the calibration with the bayer matrix in place.

[bmitchell82 (Brendan)]

+1 for what Marc said.

[E_ri_k (Erik)]

Ok I think i get it. I have abit to learn still. So calibrate the lights in mono then colour convert the lights and stack. What is the diff if i colour convert ALL frames and let DSS do everything. Am i creating more work for myself. Sorry if i dont make sense.....
Erik.

[bmitchell82 (Brendan)]

issue isn't about changing to colour, if you do the calibration will not be accurate! and you most likey will loose data which is bad!

Just follow the premise of

All photos to be in RAW not debayered
Take your photos
Take your calibration photos darks flats and bias

Apply your calibration photos to your lights

Debayer your calibrated images
Register (align) your images
Do all your noise rejection
stack your images
output them to a TIFF file
open in your fave processing software.

[E_ri_k (Erik)]

Awesome, thanks Brendan. I understand. Just need to work out how to use the software properly I think.

Erik