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Astroman
05-09-2015, 03:31 PM
Having a bit of fun with the ASI120MM. More than just a guide/planetary camera.
This is The Tarantula Nebula (also known as 30 Doradus) is an H II region in the Large Magellanic Cloud (LMC). It was originally thought to be a star, but in 1751 Nicolas Louis de Lacaille recognised its nebular nature.
ASI120MM, GSO 8" F/4 Newtonian. 100 x 5sec + 75 x 4sec subs.

EDIT: Just noticed that there is some major Jpeg compression artifacts on this image.
Atmos
05-09-2015, 03:50 PM
It is really nice and bright! But yes, pastel looking jpeg compression :)
Astroman
05-09-2015, 03:51 PM
Strange, looked fine in Photoshop, must have overcooked it along the way :D
Peter Ward
05-09-2015, 09:24 PM
Maaate...Sorry... that's a shocker.

5 second subs on H-alpha will only lead to more woe....as all you are doing
is multiplying the noise.

Try subs of several minutes plus some accurate calibration (darks/flats)

Time spent colimating the optics would also be well spent.

Stick with it and you should get some good results.
Astroman
06-09-2015, 05:18 AM
Agree with you 100% Peter. Was only using the ASI120MM too so wasn't expecting great results but was setting the mount up refining polar alignment when i saw this object was high enough. I think i will come back to it once i get a dedicated Astro camera and mire time. Thanks for the input :)
Bassnut
06-09-2015, 06:35 PM
right then. 5 sec Ha exposures. nice. worthy effort.
Astroman
06-09-2015, 06:48 PM
Not in Ha, this was just straight from the Camera, no filters... I will recheck my original post.
Bassnut
06-09-2015, 06:50 PM
Your right, not Ha , my bad.
Slawomir
06-09-2015, 07:59 PM
It would be very interesting Andrew to see how the data presents itself with stacking and a stretching only, without overcooking the nebulosity by heavy processing :question:
cometcatcher
06-09-2015, 11:25 PM
The small version looks good. I reckon you just need more frames and less aggressive processing. Think in thousands of 5 sec frames to get the total time up. This is what I used to do with my old frame integration camera for comets. So 12 frames per minute, 720 frames per hour... yeah a few thousand frames would work well I reckon.