Batch calibration without stacking

[Forum_2014]

Hi,

I have used the Preprocessing tool fine. However, I wonder if there a way to produce individual calibrated subframes without stacking them?

The reason why I ask this is to process multi-night data. Currently AA5 can only process one set of data (one set of light, dark, flat, etc). I have been told to stack each night individually, and then overlay stacked_image_nite1 + stacked_image_nite2 +stacked_image_nite3 together.

I would like to calibrate all light frames by their corresponding dark and flat, and then stack them all together without dark and flat calibration.

Thanks for the hint.

Puck

[Forum_2014]

Hi,
If you cannot reuse your darks/flats for all series then you need different preprocessings, but you can keep the result image of each preprocessing opened in the Astroart desktop for a final preprocessing on them (in memory, without dark/flats).

"Subframe" usually refers to a small part of the CCD. In preprocessing the dark/flats are always applied to single images, not to the result. You may consider also the option "save each image" to save all calibrated images on disk for a final preprocessing on them.

[Forum_2014]

Hi,
"Save All Images" is exactly what I was looking for. I kept looking into the "Extra" tab but failed to find it in the "Option" tab. Silly me. Thanks a lot. Now I can process each set to get all "frames" calibrated but without stacking. Then, I stack all calibrated frames into final image.

Sorry for the "wrong" terminology. I guess it maybe wrong one from Astronomy discipline, but it seems to be commonly "misused" by the amateur community. By "subframe", I mean the each individual shots before being stacked.

Thanks for the help!!

[Forum_2014]

Fabio:

I have successfully generate individual calibrated shots. I notice that the file size became 6 times larger (raw file: 12MB -> calibrated and color converted file: 72MB). I wonder why there is such increase on size. This makes storage and transferring of calibrated file more demanding.

Thanks for the insight.

[Forum_2014]

Hi, if the input files are from a DSLR, then they are actually B/W files with bayer dithering. Converting to RGB requires 3X space. Another 2X is caused by lack of compression and promotion to 16 bit per channel.