SharpCap Forums

Robin
Thanks I will check all of it.At least it seems closer to working now.

OK the world seems to have been saved. Well as far as my little world of astronomy goes anyway.

You will see from the video that the gotos were fine every time. No crazy missed targets this time.

All mostly centered very close. Maybe from the logs you can see what might have fixed the issue.

One or both the logs should match the video this time. I started all of it at the same time.

I first did a polar alignment. This time unlike all the others I did in the past I used my iPolar that came with my mount instead of SharpCaps polar alignment. Do I think that could have fixed the issue. Not really but it is a step I used in working on this issue that was different from the past.

I did as you asked and kept PHD turned off for the first few targets. You will see in the video I did turn it back on and use it.

It made no difference and I was hitting targets every time with it off or on. That said I did make a settings change in PHD after reading about turning off backlash in PHD, even though my mount has no backlash. Heck even the iOptron hand controller for these mounts has no settings for backlash to be turned on or off. That gearing just doesn't have any or shouldn't have any.

The change I did make was in the advanced settings of PHD. There is a check box that is left unchecked unless you check it and it is to turn off the guiding if the mount slews to another target. I checked it on because it was off, which means it was going to continue guiding even when I slewed to a new target. Now I would normally think SharpCap turns the PHD guiding off for me when I do GOTO's and we see that every time it does a GOTO. My only though here is that yes SharpCap says it turned off PHD and when you look at PHD is shows it is off not guiding or moving the mount, but what if behind the scenes it is starting up before SharpCap actually tells it to due to that unchecked box or never really stops trying to work. SharpCap doesn't see that maybe and PHD doesn't show it on the screen maybe? That would explain those last minute moves that always put the target off.


The Polar alignment change and the PHD setting were the only things I have done that were different. Up till now nothing has solved my issue, until tonight. I suspect it was the PHD setting. You can correct me if you find something in the logs and please do.

After all this I'm just happy it is all working again. I did learn a lot on this little head turner as for now I need the Tylenol?

Thanks
Video link https://www.youtube.com/watch?v=4hnVrFd6qv8

Hi,

glad to hear that things are working again. I think you are right about the changes to PHD2 being at the heart of this - something in the interaction between SharpCap and PHD2 and the mount was likely playing up previously. I didn't find any 'smoking gun' in the video or log that can 100% confirm this though....

The thing that counts against any effect from changing the polar alignment is that the initial GOTO movements were still off by a similar amount - I saw 2.6 degrees, 0.8 degrees, etc. If you had got better polar alignment then that would have improved the initial GOTO, reducing the offsets needed, but we didn't see that. One thing that I will mention is that an in-built iPolar has a small advantage over guide camera/scope polar alignment - it is immune to flex due to connections/dovetails not being 100% solid as you rotate the mount.

Anyway, all sounds good now - you can hopefully get back to using the telescope rather than worrying about it

cheers,

Robin

By chance could the iPolar camera be added for use with the SharpCap polar alignment routeine as a optional camera ?
Asking for a friend.?

ScopesNC wrote: Mon May 04, 2026 5:22 pm By chance could the iPolar camera be added for use with the SharpCap polar alignment routine as a optional camera ?
Asking for a friend.?

UN DUH SharpCap does indeed see the iPolar camera and will do polar alignments using that camera. I did not know that.

Hi,

yes, indeed, that should work I've seen some cases where you have to change the resolution on an iPolar to get a good image. I suspect that the iPolar PC software always sets a specific resolution, but the camera advertises multiple options and SharpCap happens to chose the 'wrong' one that gives a weird image.

I must go back and try the iPolar on my CEM70 again - I tried it in passing when setting up the mount and the image was pretty dreadful - seemingly faint and slightly fuzzy as if out of focus. At the time I was more keen on getting stuff working, so simply switched to alignment using a normal camera/guidescope. Are the built in iPolar fixed focus or can they be adjusted?

cheers,

Robin