Astro shot

Ok I promised I would post when I had one..

I had my first crack at orion tonight..

10 x 5 second exposures @F3.5
14 x 5 second exposures @F2.8
Stacked in registax then imported as tiff to photoshop
DSO enhanced, gradient removed, de noised and finaly the house below painted out (very poorly, didnt notice until I had done further work and it was to late to go back and rectify it).

Samsung GX10 with Sigma 28mm f2.8 lens on the merlin mount.




Earlier moon shot.

GX10 Sigma 400mm f5.6
125th second f5.6

wow that's sweet!

gorgeous colour in the nebula, really well done! I'm looking forward to having another go at Orion now that I have my equitorial mount all sorted out. Recently I've been shooting for the pleiades, but not quite got what I'm looking for yet.

Can you explain a little more about your pp workflow for Astro shots? I use Hugin to line the shots up, then registax to do final alignment and stacking but after that I get a little lost. Any tips you can offer would be very useful indeed.

Amazing lack of light pollution, bearing in mind where you are. Is that post processing, or is it particularly clear in that direction?

Dan

Hi Ian,

Orion comes out very nice. I hadn't noticed the house in the lower left part, 'till I read your comments. The shot of the moon apears a bit unsharp.

BTW, how do you test for accurate focus for your astro-images? I find it particularly difficult and am considering a right angle finder and immediate check of the focus on a laptop (using tethered shooting).

Any ideas (apart from the Hartmann masks etc)?

Greetings,
Roger.

Yes the moon wasnt very sharp.. I was having problems with a shakey tripod and terrible atmospherics that night.
I sent you a PM about focus.. suffice to say the angle finder is the way to go unless you have live view on your camera and can use either a laptop or seperate LCD screen as a focus aid.
I have also heard that two strips of masking tape over the front of your telescope will create vertical diffraction lines, you just focus until they are long and in line.. but havent tried it yet.
I havent found hartman masks work on small photographic lenses so just rely on using my eyes to get the stars as near to pin pricks as I can.

Shooting wise I set the camera on manual, jpeg, 10mp and had all the adjustment sliders in their center positions.
program line was set to MTF
I shot at ISO 400, self timer with 2s delay to avoid shake when the mirror went up and used a cable remote with locking button (in case I wanted to do any bulb shots)
Apeture ring was enabled and the camera set to manual focus.

re processing... here's what I used and did...

I took the shots and immediatly after took a 30 second dark frame.
After adding the pics to registax I added the dark frame.
I then aligned them in registax 4 using mulitpoint alignment (6 points) to counter any rotation as I only have the alt az mount up and running at present.
I then ran through the optomise and stack routines and just adjusted the wavlets until I got the best pic with the detail I wanted.. I wasnt to bothered about the nebula at that point and concentrated on the stars.
I then adjusted the gamma in registax by reducing it at its center point to darken the sky and get rid of the light pollution to some degree.
I then saved as a tiff file and moved to photoshop.
after opening in photoshop I converted the image to 8bits from 16, duplicated the layer and then used a set of actions called astronomy tools ver 1.4 by noel carboni.
I started by running deep space noise reduction
then duplicated the layer again and adjusted the opacity to taste.
I then ran Soft gradient removal and again adjusted the opacity then merged the layer and duplicated.
I then ran Enhance DSO and reduce stars (I think I ended up running this on two seperate layers and merging them for greater depth)
After running this I zoomed into the nebula area so it filled my screen and using a 1 pixel eraser brush started to cut around the red and green pixels manually so as to remove the background and leave just the nebulosity and embedded stars.
After making sure I had all the nebulosity on that layer I used a large brush to erase the rest of the layer leaving just the nebulosity.
I then used a small eraser brush set to 50% opacity to reduce the bloom on the stars within the nebula.
Finally I zoomed out and reduced the opacity on the layer to around 75% until it looked right.
I then merged the visable layers and duplicated that layer and ran a little plug in called de noise (freeware on the net) making sure I nailed some of the noise but without loosing to much detail.
Usually I would run crispimage before or after the de noise plug in but the image didnt need it.
Finally I merged all the layers and saved.
The process needs refining and I will probably re work the psd file I saved at some point as I started processing images at around midnight and finished at 3 am this morning!! but then it was my first attempt so there was a lot of trial and error going on.

I finally crawled into a nice hot bed at around 4 am this morning...

Impressive effort! Looking forward to your postings.
Roger.

thanks for the comprehensive description of your pp, that's given me some ideas to work with

looking forward to seeing more of your pics in future.