M22 from Sydney, June 22nd

[Camelopardalis]

Just a little test image, I've been trying to hone my polar alignment skills :D

C8 Edge HD with 0.7x reducer on EQ6
Canon 1100D

30x 15s ISO1600, stacked and with a little green reduction. 15s exposures were all I could get without stretched stars, but at least it's double what I've managed previously! Also, I'm not sure what the colours are supposed to be with this, Wikipedia shows more on the blue side which I don't yet see in my data :confused2: need more subs :lol:

Feedback always appreciated, still learning, and no doubt always will be :D

[cometcatcher]

Really nice image Dunk.

What I do is make the background as neutral as possible and whatever is left I keep at it is, though that idea doesn't work if there's sky glow from LP as it can mess the whole balance up.

[SimmoW]

Nice one, yes the polar alignment learning is 'fun' and so exciting as your subs go up in length.

[Camelopardalis]

Thanks chaps...it's good to get practice in even if it's in the light dome :)



So...stupid question...how do I make the background neutral? :confused2:

[raymo]

One of the penalties of having a long FL, Dunk. Even with the reducer,
your scope has about 70% more than mine. P.A. good enough for
30-45 sec subs should be just around the corner for you. Have you
settled on one method? I personally think that you'd find the P.A.
function in 3.35 easier than the polar scope.
raymo

[cometcatcher]

Most of the time I just do it by eye. But the eyedropper tool in Photoshop (or other paint programs) helps find it too.

If I stare at the monitor for too long, my brain does an auto WB lol, which is bad so I have to walk away a few times and come back when my brain has reset.

[Camelopardalis]

I was using the polar alignment routine in 3.35 raymo, three iterations and then I hit a bit of a physical wall with my adjustments and couldn't get it better. I probably could have done 20s but when I blew up a test image on the camera screen a couple of starts in the edges were starting to look non round, so I dropped it back a notch.

It'd be really nice to be able to get longer subs, not that I'm not happy with what I'm getting, but I still need to work at it some more.

[Camelopardalis]

Thanks Kevin, I'll give it a go...the other stacks from last night have got a green cast to them too, so I've got a couple of test cases to experiment on :D

[raymo]

Hi again Dunk, If by a physical wall, you mean that you ran out of
azimuthal adjustment, do an initial rough alignment with a compass, so you know you are within a few degrees before you start; making sure the azimuth adjustment is roughly mid way. If that is not what you meant,
please forgive the gratuitous advice . Incidentally, I usually need seven
or eight iterations to get it down to a minute or two, or maybe nine or ten
to get down to a few seconds. A few seconds allows me to get subs of
around 90- 120 secs. probably around 60-90 for you.
raymo

[Camelopardalis]

Thanks raymo, I usually (but not always!) manage to get the azimuth within a degree or two, it's the altitude that causes the bigger problem. Sounds like I need to iterate a few more times....here's a question...do you use the same alignment stars for each iteration?

[raymo]

Yes I do, unless one of them disappears off of the available star list due
to passing time dictating that other stars are more suitable, which can
be a nuisance. What specific difficulty do you have with the Alt axis?
You are making the same basic adjustments as you do with Az, so
what is the difficulty. If either axis is only within a degree or two, the
P.A. will be next to useless for deep sky imaging.
raymo

[AG Hybrid]

Nice one. Good work especially since it was from Sydney.

[Camelopardalis]

With the weight of the scope, counterweights etc pushing down on it, it becomes very difficult to move...but I'll keep practicing :)

[Camelopardalis]

Cheers Adrian! I could see the Milky Way stretching out overhead, which is unusual. Not any detail like out in the proper dark, just a milky patch with outline.

[AG Hybrid]

I actually had my scope out for the night on the 22nd. I could see the milky way too from my place in Toongabbie. Just a light glow that stretched for about 10 degrees. It was a good evening till clouds.

[raymo]

Hi again Dunk, I don't understand why your alt is so hard to move. I have
almost 11kg of weights, and about 10.5 kg of payload, and have no
problem moving mine. Are the adjusting bolts nicely greased? When the adjusters are both slackened right off, is the mount free to move on that axis? As I suggested in another thread, put a circular piece of Teflon or nylon down the bolt hole, so there is no metal to metal contact. You can also, as someone else suggested, push up on the under side of the scope
to ease the weight on the mount adjusters.
raymo

[Camelopardalis]

Here's a slightly more neutral version...

[Camelopardalis]

Thanks, yeah I need to give these a try...my mount doesn't move easily when the adjustment bolts are slackened in alt :sadeyes:

[raymo]

I suggest you remove the scope and the weights, and investigate what
is making the mount stiff to move in alt. It should move freely with one hand.
raymo

[Camelopardalis]

I'll get the hammer to it ;) :lol:

[LightningNZ]

Geez, nice detail!
-Cam

[Camelopardalis]

Thanks Cam! Work in progress :D