I put these up with some trepidation, but seeking comments to learn from.
All the photos are taken at prime focus of my Melon 210 using a Canon 60Da.
They do not have darks removed or flats applied.
Ghost of Jupiter: 2 minutes unguided on HEQ5 pro,curves in Gimp
Tarantula : single frame 24 minutes ISO 100 guided with 200mm fl guide scope on HEQ5 Pro, curves in gimp, Orion Autoguider
Triffid : a stack of 9, 10 minute exposures guided as above but on a Losmandy G11.
Stacked and processed with Nebulosity 3
I think I have fairly good polar alignment (DARV) for the Tarantula .
Since these pictures were taken I have acquired a zwo120mm and set up off axis guiding with it using an Orion thin oag. But now a sequence of neighbors burning Canola stubble and the continuous cloud cover has stopped photography apart from confirming that the OAG setup works.
As usual the pictures look much better at 10 meg!
Hi Chris, NGC 3242 is o.k. but the other two images have been so
pixellated and damaged by whatever downsizing technique that you
have used that it is not possible to evaluate them, other than to say
that the red in M20 is a bit too saturated. If you can try and get better
200kb images, I am sure the members here will critique them for you.
raymo
The data acquisition is very good. Quite impressive actually. Imaging at that FL is not for the faint hearted. Just need to pay attention to processing now and watch the histograms so you don't clip them and extract all the data from your subs. Looking very good.
Hello Raymo,
Thanks for your post, it leads to a question from ignorance.
I reduced the images with Gimp jpeg to say 10%.
I don't know how else to reduce picture sizes so some pointers would be appreciated.
Hi Chris, I have always used Photoshop for downsizing, which is fairly
straightforward. If you don't have PS, I think from memory that there
is a sizing function somewhere amongst the software that comes with
your 60Da, and gooday from Margaret River.
Last edited by raymo; 24-05-2017 at 02:51 PM.
Reason: more text
You have set yourself a very difficult task indeed, 24 minute sub with
such a long focal length scope; as a result, your stars are elongated.
Much better to use MUCH shorter subs [say 5 mins or so], and stack them, until you have got your guiding down pat.
Looks like your focus is a bit off, how are you doing it?
Even with a very slow scope the nebula should show stronger colour.
I don't know what is going on there, as the stars are showing strong colours.
Also, you seem to have a lot of coma in the outer part of the field.
I have attached an old image of mine that shows the colour that your image
should display. As DJT stated, try 800ISO.
raymo
