Great cluster in Hercules, from May 2009

[Tim]

I really wanted to get a decent picture of this (M13) through my C9.25 this year, however after getting all set up, I noticed that the collimation on the SCT needed a tweak. I reached around to one of bob's knobs, and the whole secondary assembled rotated in the corrector plate:(

So it was back to the GSO 8". M13 is a great target for me to go after just after twilight, to check the kit is all working nicely before moving on to other targets.

This pic is about 5 hours of 10 and 20 min subs taken over a few nights. I am rather pleased with the little fuzzy in the right-side background, as the GSO has managed to promote it from a fuzzy to a little galaxy with a glimpse of detail in the dust (see bigger pic).

There is also what appears to be a lighter blob just up and to the left of the fuzzy, anybody happen to know what that is? It may well be an artifact from a dust bunny of course

GSO 8" with TS OAG and QHY8

PHD guiding via DSI pro

Thanks for looking. Check the linked pic for full size (about 10meg or so), the version here is just a thumbnail really

TJ

http://www.btinternet.com/~mr.squeegee/Astro/GSO-m13s-from-May-09.jpg

[Beulah]

Ahh, it's great to get my fix of M13 on a cloudy night, thanks!!!

A lovely, clear image.

[RobH]

That's lovely and crisp Tim, I love the detail in the small galaxy and the fiery red of the bright star

Cheers

Rob

[Beyond_Vision]

Now thats a beauty Tim the star colour is fantastic. I'm surprised you went for that sub length I would have expected it to be over exposed. Not sure what the blob is thats to the upper left of the small galaxy.

Regards

Kevin

[barkis]

Thats just Ace TJ. M13 at its best. I like the psuedo Black Eye to the NW in the pic.

Ron.

[Tim]

Now thats a beauty Tim the star colour is fantastic. I'm surprised you went for that sub length I would have expected it to be over exposed. Not sure what the blob is thats to the upper left of the small galaxy.

Regards

Kevin

Thanks Kevin, I am trying a lower gain setting on the qhy8, that might have helped some, But I just kept upping the length and the results seemed ok.

[MikeP]

I think (from SkyMap) the fuzzy is NGC6207. There does not seem to be anything near it (can't see the lighter blob) so the blob might be the dust bunny galaxy.

My eyes are not the best but I believe there is another tiny fuzzy in the image - IC4617. It is a bit to the right of the centre of M13 and up a little bit.

Mike

[Ant]

Hi Tim,

That is a lovely show of M13. I too am suprised that the sub length was so high? But as you say it's come out really well, so lowering the gain must have helped...

I don't usually go over 1 minute on M13.

The galaxy to the right has come out well!

Nice One.

Ant

[Psychobilly]

Cracking M13... even if the 10 and 20 min subs are "un-conventional" they have definitely worked well in producign that image...

Peter...

[Aza]

Gorgeous! 20 min subs sound amazing for this target! It clearly shows though

[WebSentinel]

Hi TJ,

That is a superb M13 image! I've just looked at the full size image and it is full of galaxies - wonderful!

[Astronut]

You've caught the 'propellor' in that image very nicely, TJ.

A couple of weeks ago I had no idea where to look for it, now I see it almost instantly in the better images

[MartinB]

That's a great result TJ. My eyes did nearly pop out when I read the sub lengths, I would be awash with sky glow from my garden with those subs.

I don't think lowering the gain will lengthen the time to star saturation you will just reduce the spread of levels available down to around 45 000 when there is 0% gain. Well that's my understanding of it anyway.

[Tim]

Yeh, i'm still not clear about it Martin tbh. This happened accidentally as I forgot to adjust the gain to its usual 49% which I have used since getting the qhy8, and the image didnt seem too bad at all, so I have tried it on a few other targets.

Ha targets have seemed more difficult to process.

With no CLS filter in place, this would be just an orange photo.

[Tim]

I just read Craig Starks article again, it makes a bit more sense now.

After re-assessing the daylight pics, although I did keep the IR and CLS filters in place, max ADU on a bright target will pull up just at 65535 ADU, with a slight leaning to clip a tiny bit. I dont know what 'non-linear' data means, but it didnt sound good, so clipping it off a tad might work better. Hopefully get a chance to try it out tonight, if it ever gets dark........

[Doc]

I would go as far as to say "One of the best I've seen"