Hi Robin
I have obviously failed to communicate. So let me try again, trying not to leave out any steps and forgive me for the detail, my intent is to faithfully record what I did and hence why it leads me to think that the issue might have stemmed from the Move buttons.
In summary, when I used the Move buttons in SharpCap I had a problem guiding; in a subsequent session when I did not use the Move buttons I did not have any problem which leads to the hypothesis that the Move buttons could be the cause. Here is what I do, did on 9th April and subsequent days, which explain why I put forward this hypothesis.
My start up routine is:
1. Load EQMOD - ASCOM connect
2. Load Stellarium - connect to mount
3. Load SharpCap - connect to hardware
4. Load PHD2 - connect to hardware
5. Select target in Stellarium and slew
6. Adjust exposure and gain and Plate solve & resync using Astap via Sharpcap
7. Check focus and exposure time using Sharpcap tools
8. Start guiding - may or may not run calibration and or guiding assistant and have a habit of starting guiding before I am ready, so have to press the PHD2 stop button and start from looping when I am ready
9. Start live stacking and saving subs – check dither settings and brightness filter
On this occasion (9th April), because I wanted a specific framing of the Markarian chain to get its neighbours in the image, I needed to slew the telescope very slightly after plate solving. To achieve this I used the Move buttons in SharpCap - not something that I had ever had cause to use before.
What I can’t definitively remember of this session is whether I started guiding before I had done Step 6 Plate solving or before I had done the move to obtain the framing I wanted. However the Guide log (Section 1) suggests that I had started it, realised my mistake and hit the PHD2 stop button – as noted above, something that I am prone to do.
Having achieved the final positioning of the telescope I would have done Looping, Auto star select, Guide in PHD2 which started section 2 of the log file. Section 2 shows that PHD2 was not able to hold the guide star and I spent a long time trying to figure out what was happening. The lock position between Guide Section 1 and 2 is different, reflecting either the move or a choice of different guide star or both.
Hit the stop button in PHD2, started looping, auto star select, guide and again PHD2 could not hold the guide star (section 3 of the log: again star lock position is different to section 1 or 2) and gave up pretty quickly. Problem solving at 11pm is not my strength. Tried recalibrating PHD2 twice, failed and abandoned (sections 4 & 5).
Next session – did the same routine (i.e. including the move from within Sharpcap) same problem - it was repeatable and I took some screen grabs of the session.
Next day, found the tutorial on using PHD2 Log viewer and my Section 2 and 3 traces (see screen grab of section 2 of the log viewer) look very like the trace described in the tutorial which diagnoses an issue with the ST4 cable issue. But I do not use an ST4 cable, all connections are via USB, so problem not solved and other issues discussed in the tutorial do not fit. My trace shows that PHD2 is issuing move commands but the star is moving further and further away and if you leave it long enough (as I did in the repeat session) PHD2 will give a message saying "PHD2 is not able to make sufficient corrections in Dec. If you have done a meridian flip check to see if the 'Reverse Dec output option' on the Advanced Dialogue guiding tab is wrong. Otherwise check for cable snags, try redoing your calibration and check for problems with the guide mechanics". I can confirm that it was not caused by a snagged cable, recalibration did not work, I had not done a meridian flip. So next step was to talk to Dave Woods who had recently serviced and upgraded the mount –talked to him, provided the data and he was baffled but convinced the issue was not the mount. Talked to a friend – likewise baffled.
Next session did the usual routine but did not do a move from within SharpCap and PHD2 very happy, no problems.
I don’t like leaving problems unresolved and. PHD2 and the mount seemed to have been ruled out as the cause but SharpCap had not been, so I looked in the SharpCap forum and found the post to which I replied as it seemed to related – an issue with the Move buttons. I read your comment of 24th April as, yes there had been issues with the Move buttons, but the latest version of SharpCap might have fixed them. But my SharpCap had very recently updated to Ver 4.1.118240.0 and had not notified me that there was a new major update. You also commented on SharpCap trying to reset the tracking on EQ mounts. Having just written all this out, it still makes me wondered if this is all related.
I hope this is clearer – if somewhat long winded.
Regards
Julian
- Screenshot of PHD2 Log Viewer - Section 2
- Screenshot 2024-04-23 111317.png (143.63 KiB) Viewed 1151 times