Hi all,
Well last nights session was yet another in a long lines of wasted nights of imaging. My guiding has never worked properly. A good nights guiding is getting an RMS of 1.9. I polar align, I balance I tweak settings ad nothing seems to work. I'm at the point where I either find a solution and get my guiding under control or I give the whole thing away.
But before I launch into an explanation of my issues I'll describe my equipment & set-up routine:
Equipment- Mount - SW AZEQ6
- Main Scope - SW Esprit 100
- Main Camera - ASI1600 or 294
- Guide Scope - SW Evoguide 50 (242mm focal length)
- Guide Camera - ASI120mm mini
- Software - KStars/Ekos running on a RPI4
- Guide Software - Internal guider within KStars (though I have tried PHD2 without success
Setup
My nightly routine is as follows:
- Setup tripod and level
- Load up all of my equipment and balance. I balance in DEC first and then in RA (as per Dylan O'Donnell's advice). I find balancing on the AZEQ6 to be a pain as the clutches are quite stiff.
- Once balancing is done I fire up KStars and PA using the internal PA routine.
- I then do a star alignment so the mount knows where it is (don't we have GPS for this?)
- Then slew to my intended target and plate solve.
So far so easy but this is when it starts to all fall apart.
I start my guiding calibration using the internal guider in KStars. I've tried PHD2 but can never get it to work and I figure why use yet another piece of software when KStars does it all.
Yes I know others swear by PHD but I can't get it to work.
After guiding calibration, the mount starts to guide. It's a bit wonky at first so I always let it settle down for a few mins.
DEC is never the problem. My DEC RMS is always around 0.5. It's RA that's the problem but overall my guiding graph is horrible and regularly hangs around 1.8-2.5 RMS. Over the last few nights I've seen some weird things happening. Here's a list of some of the weirdness:
- On a good night I can get 0.8-0.9 RMS...........for about 2 mins. The mount will guide nicely, I'll have a nice smooth graph and then seemingly out of nowhere the RA graph goes crazy and my Total RMS will go to 1, then 2, then 3 then 4 then off the scale and not recover.
- Guiding will start off bad and never get good. My usual night is starting with and RMS of 2.5 and it never getting any better
- Guiding will start and the plot graph will be all over the place. Total RMS will be off the chart and the only thing I can do is stop it and do a recalibration.
So I'm at my wits end and as I said, I'm at the point of giving it all away as I'm fed up wasting hours (not to mention sleep) trying to fix this. I'm hoping the community can help me diagnose my issues. I'm starting to think it's an issue with RA in the mount. Perhaps the worm gear, belt drive or a combination of those and something else.
Yes I realise there's periodic error in RA on most mounts and I've not done PE training yet but will. Though periodic error can't explain some of the weird things I'm seeing like the mount suddenly flying off in RA for no apparently reason or having good guiding then it getting progressively worse and worse.
Thanks in advance for any help you can provide.
Rene
