Gday all.
Captured 30 h of Ha and 30 h Oiii of Vela from the 3rd Mar 24 - 18 Apr 24. Ha subs captured whilst moon was shinning and Oiii during the new moon. Could not get any more data due to trees in the back yard and another shiny moon. 15 Ha and 15 Oiii per 12 panels. I took one set of flats about that half way mark when I assumed I could get enough data for a photo and 40 bias.
Processed in Pixinsight using MosaicByCoordinates and GradientMergeMosaic using HOO combination.
Great result and wonderful image from all that hard earned data
Astrobin really does it justice
Well done indeed !!
Martin
PS: I’m glad I’m not the only imager that has used Bias to calibrate Flats. I’ve been advised both here and on other forums to use Flat Darks in lieu of Bias as best practice to ensure any dark current is calibrated out of the Flat. So I’m using Flat Darks now. For the life of me I can’t tell the difference between Bias and Flat Darks ( even down to pixel level ) as I’ve compared a few different broadband and narrowband images taken from both Bortle 8 and Bortle 3 skies. My Flats are usually 0.1 sec to 0.5 sec for Broadband and 1 sec to 5 sec for Narrowband ( I take 40 Flats ) and I suspect that the resultant dark current would be extremely low. I’m sure the Bias comments relate to other CMOS cameras , not the 2600MM ( super low noise high QE camera )
I’m still going to keep use Flat Darks !!
Fellas thanks for the thumbs up. Glad you liked the photo. Ta
Martin, I have seen so many different opinions on the net in regards to flatdarks and bias for the 2600. Then I saw threads about the speed of a bias..not to mention filters. When I went to filters I asked on another forum about flats with filters. Crikey response was take flats for each filter and take them every night. I did that for a short time I can tell ya. More calibration frames than subs. Didn't know how to stack them either.
So, Plenty of time on my hands, I tried darks, flat darks, bias and stacked in WBPP in PI. I even did flats with no temperature (ASIAIR threw a warning I should turn on the temp) so I used -30 and changed the gain. I take all my subs at -10 100 gain. Damm if I could see any difference. No amp glow with a 2600mm, tried no darks, no difference to my tired eyes. Then to make it worse I read a thread on ADU for flats. The ASIAIR will take them auto at around 30000. Then I read 24000, and another thread 27000 to 30000. Blimey, keep mine now at around 250000 - 260000.
My first camera was a 183 colour which I used from Sept 22 to Mar 23. Thought I was a guru and went mono using the 2600mm. I have only been doing mono for a tad over a year.
Using the correct darks, bias etc...confused as. So I now stick to just to (40) bias master and (60) flats/filters for the whole photo.
I am aware that technically there are reasons behind it all.
I’m going to stick to full calibration suite for both my 2600MC and 2600MM ( Lights , Darks , Flats and Flat darks ) just to ensure all bases are covered, dark current , hot and cold pixels , Dust donuts and vignetting ( my TS GPU coma corrector causes terrible vignetting in my 8” and 10” Newts )
