Starfield Astro Shots (for Andy_Fozzy)

jgs001

jgs001

Brian Cox
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John
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As requested in the Insomniacs thread, a couple of starfield astro shots.

Both images, 450d mounted on a tripod, kit lens at 18mm, 30 second exposures F3.6 @ISO800, both have had light polution removal and sharpened.

30 frames (15 minutes) stacked together, cropped. Region of Arcturus.
arcregion.jpg


28 frames (14 minutes) stacked together. Region around Cygnus.
starscape.jpg

I'd been hoping to get at least 40 frames if not more, but clouds stopped play.
 
I also managed a shot of Jupiter at 250mm. 1/3 Sec F5.6 @ISO800. Jupiter is burned out, but as I was trying to capture the Galilean moons in the shot, this was the only way. It's a bit carp as images go, but to get a decent view would require either a much longer focal length or about five minutes of AVI from a webcam on a scope to stack.

IMG_0763.jpg


From left to right:
Calisto, Ganymede, Europa, Io, Jupiter and the final dot is HP95077 (a star 186 light years away.
 
Thanks Frankee and Jayst. For reference, here's a single frame from the stack of 28 (second starscape around Cygnus area), totally unprocessed.

IMG_0725.jpg
 
Would love to know exactly how you achieve these - in London the light pollution is horrendous but at my Tamworth place the sky is crystal clear - I would love to have a crack at this...do you have a guide you can link to?
 
John, Sorry no, this is what I've picked up so far from others in the Astro world. But here's the basic workflow. Set the camera on wide angle on a tripod, pointed up. Focusing is a toughy, on the 18-55 kit lens, it's not at one end of the focus travel, so I normally end up taking a few throw away test shots to tweak. As this is a non tracking static mount (not able to track the motion of the Earth), then you are limited to somewhere around 30 seconds ish. This will depend on how wide an angle you can go to, you need to test this for your setup. Then, take as many exposures as you can. The more exposures, the more detail can be pulled out. There will be a limit to the number of exposures, as the Earth rotates. Then take some dark exposures to reduce noise, keep the camera settings the same, but put the lens cap on. You need at least three, but probably won't make any difference if you go beyond 10. I forgot to take darks last night, as I wanted to grab the shot of Jupiter.

Then take all the images, load them into DSS as either Light (images) or Darks (noise removal). Click Stack checked pictures. Go to bed, have a meal, something like that. This process can take a while. DSS will work out the alignment of the stars, any field rotation etc, and adjust it back again. Once DSS has done it's work, save the image, check the box for embed adjustments only. Open the TIF in your editing program and use levels and curves to bring out the star field, there's a guide here. I then use some PS actions written by Noel Carboni to remove light polution (details here) Then unsharp mask resize etc.

HTH and Good Luck
 
Last edited:
WOW mate, they are superb.
I love em!
#2 especially, as it shows the density of the sky.

I was going to ask, but Dark Star done it for me :clap:
So thanks mate!

And thanks John for posting the shots, and indeed how to do it!
 
jgs001 said:
John, Sorry no, this is what I've picked up so far from others in the Astro world. But here's the basic workflow.....

HTH and Good Luck
Click to expand...

Many many thanks for taking the time to detail all that, I'm very grateful (y)

I shall give this a go - fingers x'd :)

John
 
Thanks guys. That image in #2, I pointed the camera at the plane of the Milky Way, so the starfields are far more dense anyway. The other image is not pointed into that plain.

Good luck, look forward to seeing how you get on.
 
jgs001 said:
As requested in the Insomniacs thread, a couple of starfield astro shots.

Both images, 450d mounted on a tripod, kit lens at 18mm, 30 second exposures F3.6 @ISO800, both have had light polution removal and sharpened.

28 frames (14 minutes) stacked together. Region around Cygnus.
starscape.jpg

I'd been hoping to get at least 40 frames if not more, but clouds stopped play.
Click to expand...

Hope you don't mind but there's a lot more data in that second shot Just had 2 minute play in PS

Steve

starscape-edit.jpg
 
Wow, that's astonishing Steve. What did you do ?
 
jgs001 said:
Wow, that's astonishing Steve. What did you do ?
Click to expand...

Hi John

There's lots more in the first shot too..

Original:
arcregion.jpg



Edited
arcregion2.jpg


I don't know what camera etc. you took these with but editing a JPEG loses a lot If you've taken these in RAW format there's probably even more data there, I just stretched the levels a bit more, a touch of curves :)

Nice shots BTW :clap:

Steve

Steve
 
Thanks Steve. Yep shot in RAW. I'll go back and stretch away.
 
jgs001 said:
Thanks Steve. Yep shot in RAW. I'll go back and stretch away.
Click to expand...

Don't forget to post the results.... BTW it might help to convert to TIFF first (depends what software you're using) :)
 
DSS takes the RAW, stacks them and produces a TIFF as the output file. I'll add it in once I've had a play.
 
Here's the reedit of the Cygnus region shot.
starscape2.jpg


There's more light pollution here, removing it all removes the stars.

Steve, I hope you don't mind, but what did you do in levels ?
 
Hi John

That's looking excellent and really bringing out the detail :) don't confuse LP with the glow from the Milky Way ....

Just keep at it, stack with DSS and process in Photoshop. if you capture DSO's select them and process as a selection. You also have some vignetting try some some flat field frames to add to the darks and lights, works wonders :)

You've gone from Good to excellent in 24 hours.. keep trying and asking questions, nothing to lose.

Steve
 
Cheers Steve. I forgot the Darks :bang: and have no clue about flats at the mo. I've not tried for DSO's as yet, I don't have a scope adapter and T-Mount, it will come.
 
jgs001 said:
Cheers Steve. I forgot the Darks :bang: and have no clue about flats at the mo. I've not tried for DSO's as yet, I don't have a scope adapter and T-Mount, it will come.
Click to expand...

I'm sure it will come..... The darks are simply used to reduce noise and flats are to give even illumination, reduce any dust, vignetting etc.. As far as bringing out DSO's with selective processing this is a shot taken a while ago (Orion nebula)..... Not the best shot I know but shows what can be done with selective processing .... (no darks or flats - hence the vignetting etc. and only showing selective processing)

Steve

orion-neb.jpg
 
Cheers Steve, I've used darks before when I was trying this with the Z2 (it just couldn't do astro shots very well), I just forgot to take them since I got the 450d. Cool M42 by the way.
 
Thanks Whittie. The PP on astro shots is a really really steep learning curve.... When the resultant image comes out of DSS it's almost black and looks like there's no details in it...
 
Love the pictures. :eek:
I've got to have a go at this.
 
Wow, some excellent pictures there by all.

Splog, what equipment did you use for the nebulae? Was it on a tracking mount or not?

The best milky-way shot i've managed so far (damn these long summer days) was taken here at home last winter, 8x30sec@/f4 stacked with rot'n'stack.





I do plenty of star trail shots, but yet to manage any DSO's though, looking at getting a telescope soon to try some out.
 
_belial said:
Wow, some excellent pictures there by all.

Splog, what equipment did you use for the nebulae? Was it on a tracking mount or not?
Click to expand...

It was taken with an EOS30D and Canon 180L macro (a real pig to focus) and yes it was on a small tracking mount :)

Steve
 
One last one, I found when I revisited the RAW files, the cause of some of the oddness and red patches. Clouds. Having removed the cloud covered shots and reprocessed 17 of 30, giving 8.5 minutes, this is the result

cygnus.jpg
 
Thanks Andy. Take a look here
 
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