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Zubenel
22-03-2018, 10:46 PM
After a Cyclone decided to divert its path last week away from the Queensland coast we had a one night window of clear excellence which i took advantage of. Eta Carina seems to be the flavour atm and I have been wanting to have a crack so here is my first attempt. Due to the 2500mm focal length "Zamar" will always suffer from a small FOV but from what I have seen here , she does give a less common vista.. .. Details~ 239 x 2 sec subs and 30 darks stacked in Sequestor with post ed in photoshop. We managed to not blow out the Homologous whilst enhancing the surrounding Nebula. No temp or Hue changes were made. I could have cropped it a bit to reduce the coma at edge of field but would have lost the dark lane"elbow" and open cluster Trumpler 14! Critical feed back welcome as i want to improve !! 225460

raymo
22-03-2018, 11:53 PM
Nice job; IMHO making the background a bit darker would make
the nebula really pop[ as the youngsters of today would say].
raymo

PKay
23-03-2018, 09:27 AM
Good one Wes

You have captured the 'Keyhole' ( i think it is).

Many stars have little dark dots on them, got no idea what causes that.

Someone will know.

N5SE
25-03-2018, 05:26 PM
beautiful

Zubenel
26-03-2018, 07:25 PM
@ PKay.
"Many stars have little dark dots on them, got no idea what causes that."

I am unsure what is causing this. Advice welcome :thumbsup: I first thought that I may have been over saturating Pixels but if that was the case the homunculus which is the brightest object in the field would have been effected. I then thought that it may be some setting in Sequator but other stacks I have done like M42 would have done the same??? Thanks for your kind comments Pkay Nzse and Ramo.:thanx: It's a "Dark Art" which will take a long time to master, may be that is the attraction with this pursuit?? or never at all considering the use of an Alt Az mount compared to say , a guided EQ mount. ( Don't get me wrong I'm not whinging). We use what equipment we have and weigh the costs to benefits . (Costs are easy to define. Benefits are subjective and had to measure).... Cheers

gb44
03-04-2018, 06:57 PM
Good job Wes.
I think the black looking dots on the star fringe may indeed be from oversaturating the blue channel in combination with the field rotation due to the dob mount.
Plus the optical centre of the pic is mid left so that might add to the issue.
Might have to get an equatorial platform!
The use of a coma corrector would be good ... I'm selling one(!) but you might wanna get a upgrade to a Parrcor or Baader MPCC mark 2 or better.

The dslr isnt that sensitive to blue so there shouldnt be so much in a pic. The background should be a lighter black....?


GlennB

gb44
03-04-2018, 07:00 PM
Wes
I saw a great galaxy pic - narrow field, as you will get - with a ZWO camera. It was a stack of 6000 x 2sec exposures and it was great.
ImagesPlus would cope with field rotation.


GlennB

Zubenel
24-04-2018, 05:42 PM
Thanks Glenn , ImagePlus looks interesting in leu of "renting" PS !!