M83

[gregbradley]

Well its a fabulous Southern target and its in a good spot for imaging right now.

Perhaps not the best timing to post this after Wolfgangs effort but here it is.

I was happy with this as I used a Tak 1.6X extender on my TEC180 to get F11.2 and a larger image scale. This was also taken from my front yard! FLI ML8300.

About 6 hours total. I probably will take some more once the moon goes.

Some subs had a few tracking issues but couldn't afford not to use them. Also a few had softer focus. Again, tough luck when you consider getting clear skies, no moon, time to image etc etc.

http://upload.pbase.com/image/124000305

Greg.

[h0ughy (David)]

Greg it is a wonderful shot -and forgive me, but - i think the sky background seems way to "black" and that it seems that you may have clipped the image

[telecasterguru (Frank)]

Greg,

I love the colours. Nicely done.

Frank

[renormalised (Carl)]

Nice shot, Greg. Plenty of detail in the arms and nucleus...nice colour!!

[gregbradley]

Originally Posted by h0ughy

Greg it is a wonderful shot -and forgive me, but - i think the sky background seems way to "black" and that it seems that you may have clipped the image

Hi David,

Yes it is a bit black. I was battling a bit of colour noise. Perhaps more exposure will give me more signal to noise. I know what you mean and I usually have the background much lighter for galaxy shots. In this case there was a bit of noise.Perhaps it can be lightened a bit. I went to a fair bit of trouble to clean up noise. I normally image from my dark site where it is almost fully dark. My new house is quite dark but a smallish amount of light pollution still. Something new for me!

I've reworked it has a lighter background albeit a tad noisy but that's not so bad with galaxy shots. I agree with Mike on that point.

Greg.

[Bassnut (Fred)]

Nice and bright Greg. Dunno about and extender on such a small apature tho, seems very noisy for 6 hrs. Do you think f11 is a good idea long term on a refractor?, your going to be makeing some insane exposure times on anything dimmer. NF is for the CDK methinks.

[multiweb (Marc)]

Love the colors but I have to agree with Fred. The only way to get good details on that one is with aperture from a dark site with good seeing. How's your new obs coming along? You're going to put some large aperture instrument in it?

[gregbradley]

I redid it from nearly the ground up this afternoon. I realised you have to be a bit picky with the subs. They varied quite a bit in quality in the luminance. Some weren't fully in focus and some had tracking errors that were too bad. Some were really really sharp. I guess the seeing shifts as well during the night. Attention to focus is critical at F11.

This result is much better:

http://upload.pbase.com/gregbradley/image/124000305

And also the crop turned out OK as well, in fact I prefer the crop:

http://upload.pbase.com/image/124075461

Definitely the job of the larger scope is targets like this. But its nice to use the APO in the meantime. I start construction on Monday and the scope should be here within 2 weeks. A pier is being made at the moment as well so it should be all up and running within a month.
It just makes the APO a more versatile instrument being able to extend it.
Greg.

Originally Posted by Bassnut

Nice and bright Greg. Dunno about and extender on such a small apature tho, seems very noisy for 6 hrs. Do you think f11 is a good idea long term on a refractor?, your going to be makeing some insane exposure times on anything dimmer. NF is for the CDK methinks.

Originally Posted by multiweb

Love the colors but I have to agree with Fred. The only way to get good details on that one is with aperture from a dark site with good seeing. How's your new obs coming along? You're going to put some large aperture instrument in it?

[Bassnut (Fred)]

Nope, no good (for 6 hrs). I think youd be better off imaging without the extender and croping , your not short of res.

[gregbradley]

There's no substitute for aperture for galaxies for sure. Here is one I took last year at F7 with the TEC180:

http://www.pbase.com/gregbradley/image/109630053

It also has some Ha in it.

The TEC is best suited for a wider field objects and with the 16803 chip. That's where it shines most.

Greg.

[spearo (Frank)]

Hi
I think your original (or the one I can see in the first post is nicer / more pleasing to the eye than the closeup.

This could be because the closeup reveals a bit too much the effct onthe stars within the galazy of some processessing such as contrast or unsharp mask. the edge of these stars is a bit too sharp i think inthe closeup.

I really like the shot in the first post personally, ad I have a general liking for a nice black background but i know i'm the exception on this .

well done
frank

[rwong]

It is a wonderful shot. Very pleasant colours.

Cheers
Reg

[gregbradley]

Thanks guys.

I added a small amount of Ha to the original image and it fires it up a tad.

Greg.