Last night was unusually good up here. Here's 60x2mins using the DSI II through the Newt. The guiding is still playing up but apart from the eggy stars I'm quite pleased with this image.
In PS, resize the image size times 4 (well, possibly less if the original was larger, say 2) to allow finer control.
Then Control A (to select it), contol C to (to copy it), contol V (to paste it). Now you have 2 layers of the same image. Set the upper layer to "darken" blend mode, then make sure the upper layer is active, and click on the "move" tool. Then click on the image again and use the arrow keypad keys to move the top layer left/right/up/down to make round stars. When smick, click on "layers" tab and merge, to get back to one corrected image. Then make "image size" back down to the original size.
This only works if there is slight egging, too much moving will induce artifacts.
A stunning image Peter; great image scale and a large field too – well done! I hear ya about the elongated stars – I’m still ironing out my set up too!
I've been working on improving the guiding so I can have longer subs and don't need to correct the imperfections in post processing as per Peter's recommendation.
I spent some time on the weekend improving the balance in both RA and Dec however this seems to have made my guiding worse - especially in RA where I can see the guiding rocking back and forward. Last night I deliberately imbalanced the rig a bit in RA but not quite back to how it was but it still wasn't enough I guess. Are there any guidelines on how much imbalance I need or how to measure this apart from trial and error?
I've also encountered some issues in DEC where I've had to increase the guiding (rate?) from 0.3 to 0.6 in EQMOD to get Guidemaster to complete the calibration - it was complaining there wasn't enough movement in the star during calibration. I'm guessing this is a backlash issue however this seems to have got worse (since I changed the balance) for some reason. I'm wondering if something has become loose within the gear train? Is there a way to measure backlash in DEC - I know Guidemaster reports if it detects backlash but doesn't really quantify it. I assume the fix is to adjust the gear mesh?
I've also failed to get rid of my flexure issue despite removing my long collimation bolts. Anyone have any tips on how to track this down? I suspect it might be in the guidescope focuser - guess I could switch to the ED80 as guidescope and see if it improves.
Apart from these minor issues things are going well. I'm hoping for some help at Astrofest to resolve all these issues if anyone has any ideas.
Nice and sharp with a good amount of detail Peter.
We are using a DSI PRO as a guide camera and have found that when the scope is in certain positions the screws on the focuser seem to back off slightly. Am looking at making a bracket in order to bolt down the camera to a sturdy part of the mount. Fred ( Bassnut) did advise he had done this some time back.
Thanks David. I think I've got the DSI mounted pretty firmly - changed to three locking screws on the focuser already although there is some weight in the camera and filter wheel so I should have a look at that.
Great image scale Peter. Very nice. Once you get your set up tuned so you obtain round stars, the results will be awesome. Data could do with a little more stretching IMO, but its all there with good details present. Looking forward to seeing more. Well done.
Cheers Jase and Ric. I'm quite please with how the longer subs turned out but the guiding errors and flexure are really driving me nuts. I wish there was an easy way to eliminate some of the variables. I'm toying with getting the mount overhauled next week in time for Astrofest.
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Not much difference if you ask me..? 
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