Horsehead and Flame - 6hrs with unmodded canon 400D

swannies1983 (Dan) · #1 26-01-2012, 11:37 AM

Weather in Adelaide has been rather kind to me over the last week with lovely clear skies. Certainly not perfect conditions as each night has either had gusty winds or the ambient temperature was sitting in the mid 20s. I have recently put up some tarp as a windbreak, which has helped significantly dampen the wind.

Anyways, I have spent the last week imaging the horsehead and flame. I think this is as far as I can go with my setup unless I push for longer subs (15mins). Probably not doable with the wind and would be a test of my polar alignment as I don't guide in DEC due to unresolved issues in the DEC axis.

Here are the details
Scope: 8" Newt
Mount: EQ6
Camera: unmodded Canon 400D
ISO800
Exposure: 39x8mins and 5x10mins (total ~6hrs. Taken over 6 nights)
Guidescope: 60mm f/11 tasco refractor
Guidecamera: unmodded toucam
Filter: Hutech LPS
Ambient temperature: ranging between 18-27 degrees
A few nights the wind was gusting up above 30km/hr.
Stacked in DSS (lights, darks and flats) and processed using PS, plus Astronomy Tools actions.

Picture here

Any comments/advice/suggestions as to whether I can bring out anymore detail or is this probably the limit of what I can achieve with this setup?

P.S. I have generally uploaded images via the "manage attachments" area but my images always tend to compress to around 50 even though the image is generally greater than 500? The uploaded image then looks terrible. I know the limit is 200 and see that the size is much closer to this in other threads. I just don't know why mine compress to such a small size.

Lester · #2 26-01-2012, 12:07 PM

That is a very nice view Dan, with crisp stars, excellent tracking. The wind break is a big plus and obviously helped.

I size my images in Photoshop and save under "web and devices" . Or use free version of Photobucket, then you can use a link to there and larger image size than 200, which helps.

All the best.

multiweb (Marc) · #3 26-01-2012, 04:36 PM

That's very nicely done and processed. Excellent work.

swannies1983 (Dan) · #4 26-01-2012, 06:38 PM

Thanks Lester and Marc. I will look into ways to save the image.

I'm not sure on the colour of the nebulosity. Does it seem OK? Obviously I'm not going to get the detail that a modded cam/ccd achieves. I could boost saturation in the red channel I guess.

Does this look any better?

jjjnettie (Jeanette) · #5 26-01-2012, 06:57 PM

I'm sure you should be able to tease a lot more out of this one.
Apply small adjustments using curves , then fix your histogram in Levels, curves then levels, curves then levels. etc etc
Alnitak is a right b*#ch to keep under control. But by using small adjustments, you can usually keep the upper hand.

swannies1983 (Dan) · #6 26-01-2012, 07:30 PM

Thanks. I have done a few more small adjustments. Data is there. I just need to learn how to bring it out!

Updated picture. I left the saturation as is in this one for now.

Ross G · #7 27-01-2012, 10:13 PM

A nice Horse Head photo Dan.

Very sharp and smooth colours.

Ross.

swannies1983 (Dan) · #8 27-01-2012, 11:54 PM

Thanks Ross. I'm still not happy with the processing but I guess I should be happy to get anything with an unmodded camera.

mswhin63 (Malcolm) · #9 28-01-2012, 02:29 AM

Really nice

. Now I know why a 4 minute exposure couldn't get much for me. Real challenge.

swannies1983 (Dan) · #10 28-01-2012, 09:16 AM

Thanks

. Yep, I could just see the horse head on my 8 min exposures @ ISO800. However, this was only on the nights when the temperature was below 20. I reckon to get anything more, I would need to push for 15min exposures. But noise will be a problem.

jjjnettie (Jeanette) · #11 28-01-2012, 10:50 AM

I love that last repro. The Horse is standing out beautifully.

RobF (Rob) · #12 28-01-2012, 01:33 PM

Great work. Might be worth checking your vanes are perpendicular (e.g. compass or dividers to check secondary is symmetrical and centred) to get the diffraction spikes on Alnitak tighter.

Apologies for playing with masterpiece - nice image and it's raining

swannies1983 (Dan) · #13 02-02-2012, 11:55 PM

Quote:

Originally Posted by RobF

Great work. Might be worth checking your vanes are perpendicular (e.g. compass or dividers to check secondary is symmetrical and centred) to get the diffraction spikes on Alnitak tighter.

Yeah good point. I think I stuffed it when I last collimated the scope.

Quote:

Originally Posted by RobF

Apologies for playing with masterpiece - nice image and it's raining

No worries at all. Any help is much appreciated as I'm only just at the initial stages of learning how to process images. What extra steps did you make?

RobF (Rob) · #14 03-02-2012, 05:46 PM

To be honest I don't remember exactly now Dan. Would have been along the lines of some more stretching and black point adjustment, some masked noise reduction for the fainter areas (I think) and a little bit of high pass filtering in "Overlay" made in Photoshop. Pretty sure I boosted a saturation a little and added some PS "vibrance" too.

Hope that helps a little.

Rigel003 (Graeme) · #15 04-02-2012, 12:13 AM

Nice image Dan, and a great result from an unmodded DSLR on warm nights. I take my hat off to you for the 6 night marathon. You can just see Alnitak's companion on one of the diffraction spikes. As has been mentioned, it shows sharp guiding, fine detail and subtle processing. I'd work a bit on some noise removal in the faint areas and maybe bringing out a touch more detail in the bright bits.

swannies1983 (Dan) · #16 12-02-2012, 10:08 AM

Cheers

Yep, I noticed Alnitak's companion, particularly when focusing using the Bahtinov mask.

I will continue to work on the image. I think I really should invest in some good image processing books.