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View Full Version here: : Showing a very bad Swampy M8 - it really was murky last night


h0ughy
13-06-2010, 07:36 PM
its horrible:rolleyes:, i knew the guiding was all over the shop last night and the mount seemed to be fighting the tracking all night - well it showed. this rates as one of the worst shots of this i have done. it really deserved the starless treatment. I certainly do not have perfect round stars:rofl:

i was greedy as it really wasnt good conditions for imaging:help:

Hagar
13-06-2010, 07:44 PM
Might have been poor conditions David but the image aint to shabby at all. You seem to have had more tracking problems with slightly elongated stars than you did with the capture or processing.
You're becoming a bit of an imaging machine of late.

h0ughy
13-06-2010, 08:07 PM
MMMMM MORE PHOTONS>>>>>>>NOW Mmwmwwaaaahhhhhh


ok i am not quite to that stage yet - but getting close:rofl:;)

Thanks Doug, but the tracking last night was woefull due to the star i was guiding on jumping around - heaps:sadeyes:

David Fitz-Henr
13-06-2010, 11:41 PM
Except for the elongated stars it's not really too bad at all. Last night started out well for me but seeing deteriorated over the space of just half hour or so :-( Tonight is shaping up much better though ...

RobF
14-06-2010, 09:01 AM
I agree with Doug - not shabby at all for a night's work. The obs much be helping with productivity. I seem to recall seeing a fantastic M8 in progress at Qld Astrofest last year? Mind you, you can't have too many shots of such a great object.

h0ughy
14-06-2010, 09:44 AM
yes i have noticed that even though we have had some clear nights the seeing has let it down. The last time we had good conditions was during a full moon in beginning of May.



Ah that was Al Meehan using his 10" ;)

jjjnettie
14-06-2010, 09:54 AM
Arrrgh, I've given up on autoguiding Dave. Life's too short to battle software/hardware issues.
Considering all the hassles you went to capture it, it's a lovely image.

h0ughy
14-06-2010, 10:08 AM
Your quite right, but whats your problem JJJ? First i have heard of it, or read anyway. Can i ask what you're using?

gregbradley
14-06-2010, 10:43 AM
Hey what game is this? Say how bad the conditions were and then put up an image that is actually quite good :P

Nice colours in the neb itself and quite a bit of detail.

Did you try the darken layer and offset filter technique to round the stars up?

It sometimes damages the neb if you have to work at it too hard so you can select the stars as a layer and do only them or lassoo them and only do stars not in the neb or do it as a hidden layer and rub through only the areas where it doesn't effect neb details.

What was the problem you had with autoguiding?

My little Astrotech66ED and ST402ME continues to be a simple and effective autoguiding solution up to 1260mm focal length so far.
Always lots of guide stars always sharp enough and not so long focal length that the autoguider is chasing the seeing too much.
I can get it down to .5 second or less exposure times on a good night and get slightly better results than 1 second guide exposures.
Autoguiding is usually as good as your polar alignment, your balance of your OTA/camera and squareness. After that it can be further tweaked. I find you can get considerably different autoguiding errors from different guide stars in the same field. If I find the errors higher than normal my first action is to select another gudie star and see how that one goes. Not sure why that is. Some stars are binaries and when the guidescope doesn't split them they look a bit elongated on one side. I usually select the brightest sharpest looking star. Not one that is too bright and bleeding over in the image but one that will survive a small light cloud passing through the field.

I use 1 second guide exposures or less. For my setup that is ideal. Longer exposure times means the PE builds up too much. And my Tak NJP mount has low PE to start with (about 3.5 arc seconds or less last I checked). At the end of the day you will also need to get the PE down with PE software or work on your mount to get it lower (better worms, coatings that are available for the gears). Or if feasible a better mount. I like the Tak as it is user friendly and very simple to use. One or 2 synchs and it does its go-tos. I usually park it after use so I simply turn it on and off I go with the free driver by Chuck Faranda.

Greg.

jjjnettie
14-06-2010, 11:03 AM
I've had problems with my guiding since the very beginning. For months it's been one problem after another. So I'm manually guiding now Dave. I've been using the Phillips webcam, K3 and StarTarg (it has a closed box in the centre of it's reticle, easier to use than the one in K3). Then for eye relief I open Magnifier and zoom in at 18x. Then I just sit back and make adjustments as necessary.
But....now I'm up and running with the RC, I'm going to be using the Gstar to find guide stars in those faint fields.

h0ughy
14-06-2010, 11:25 AM
Greg i have not changed a thing - all the other shots i have taken have had perfect round stars and i have been happy with it but this night the guiding was horrible. I have yet to set up with full computer control and software control of guiding etc (i still cant get the blinking cable to work with the gemini/rs232). You might be right about the choice of guide stars, and come to think of it it did look slightly long but i thought that was the seeing?

h0ughy
14-06-2010, 11:26 AM
so you had no luck using the webcam and PHD

gregbradley
14-06-2010, 01:33 PM
If you normally have decent autoguiding and all of a sudden it goes bad I usually check cable drag. Cables can be pulling on the rig in some angles.

First thing though I would simply try another guide star to see if that made any difference.

You can also fiddle with the guide rates on the RA and Dec to compensate.

You also know of course when you cross the meridian you have to check the reverse X button? If you start autoguiding and the RA errors start climbing fast you need to check the reverse the RA commands because north is now south or vice versa. In other words the correction going to the mount in RA is correcting the wrong way.

Greg.

h0ughy
14-06-2010, 03:42 PM
i shutdown and restart PHD every time - no matter what that way it keeps no settings from the previous object

irwjager
14-06-2010, 04:00 PM
Horrible swamp? It puts to shame most of my stuff - I'd be pretty chuffed with an image that's even close to this! :lol:

Can I ask what equipment do you use for 'throwaway snaps' like these?

Passed it through StarWipe, just to get a peek at the core - hope you don't mind!

h0ughy
14-06-2010, 04:47 PM
127Ed refractor, canon 40D cooled, G11 Sirius Dome, dog, Streetlights and bad guiding

irwjager
14-06-2010, 05:49 PM
:lol:
There's your problem - dog! I use two fluffy piggyback mounted cats and haven't had a swampy shot since. :P

Seriously though, you're getting some impressive shots from your gear & processing.

Bassnut
14-06-2010, 06:17 PM
Exactly, check yr email Dave for how that process looks, roughly :P.

Anyway, excellent pic overall, sparkling stars and nice neb colour balance :thumbsup:.

h0ughy
14-06-2010, 07:06 PM
Guys - i havent used photoshop at all, i am a bit of a klutz with that i am afraid. I would need Special High Intensity Training to be able to use it:rofl:

Bassnut
14-06-2010, 08:39 PM
OOOh, Dave, you really need to get your shiet together :lol:. PS is more than half the jurney to a good pic, you HAVE to learn it.

May I recomend Ron Wodaskies "Zone System" book for an excellent start.

Yes, you need Special High Intensity Training unforch, theres no way round it, itll be a loooong painfull experience.

You get excellent results without PS I must say, but you need PS to go the next level.

Now Im thinking the steps I emailed you based on Gregs suggestion (star rounding) are going to be gobbledegook, but you really need to get started sooner or later, its enevitable.

h0ughy
14-06-2010, 09:27 PM
:rofl: yep bought the book a while ago.... still havent read it yet:help:

Bassnut
14-06-2010, 10:07 PM
DAVID ,:poke::poke::poke::mad2:

h0ughy
14-06-2010, 10:33 PM
Sorry Fred......................:(