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Accurate drift aligning is hard to beat because it is the actual thing rather than an estimation of the thing (with models etc).
Like in building there is the object and then there is the measurements of where the object should be. Not necessarily the same at all!
Try putting in the exact time. Check your long/lat/altitude and make sure that is exact. Do you callibrate your guider often?
Is it square to the scope?
When I accidentally erased my PEC curve guiding was worse. I just recorded a PEC using the Sky 6 and it looked like the original
(much like a sine wave and gentle not heavy) and that improved things. Check your balance especially at the angle you are most likely to image at. If your setup is top heavy that will shift balance as you change angle. Make sure your mount is level and I take it eveything is stable.
You might try using 1x1 binning on your remote guide head and a brighter guide star if you can find one. I found if I could use 1x1 it got better results than 2x2.
I tried to load Automapper and it came up with an error message saying Pinpoint was not detected and to load it first.
There is an update to Automapper so perhaps I need that but I think I need Automapper in first for the update to work.
My guiding is set to 4 second exposure times. I set min move to .01 and max to .5. If you get an error bigger than .5 its got to be PE or seeing or bad polar alignment. Firstly I use 2x2 binning on the ST402. I pick a star that is reasinably bright but also quite tight looking. I don't usually pick a fat star. I get quite a large difference in guiding errors between guide stars. A tightly focused brightish small star is the go and I use subframing to frame it but not too small so the guider can reacquire the star if cloud interrupts.
I see errors that vary as the seeing and PE go through their cycle but it would look like this:
.1, .2, .4, .28,.5, .05, .4, .66 so a range between high of about 1 and a low of about .05, average would be about .25 at a guess perhaps higher. When the scope is pointing closer to the zenith the guiding errors are noticeably smaller.
I have found this combo callibrates very quickly. In fact its one thing I like about the PME, it takes about 30 seconds to callibrate the autoguider and it almost never fails compared to hell in the past with other setups. So I tend to callibrate more often now and that helps.
I also make sure the 402 is square to the scope as it seems to be knocked out of whack easily.
I think Marcus's approach is good, getting a fairly large model and using its recommendations. The problem I had was I drift aligned using the camera and then did a 10 point T-point model and I followed its directions and it made the guiding worse. So not a large enough model, not accurate enough time would be the cause I assume.
I'd like to a get a big Tpoint model not so much for accurate go-tos as I get close enough to find things but to use ProTrack to gain an extra edge in autoguiding.
With the MMOAG and ST402 I find the camera is not stable in the eyepiece holder of the MMOAG. It can rock. So I adjust it so the stars are round rather than eggy which means it is tilting.
I am going to buy a cheap parfocal ring and attach it to help find focus easily and stabilise the 402 in the eyepiece holder more.
Greg.
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