I copied this from the focuser logging the other night:

2019-10-06T21:45:24 Capturing image...
2019-10-06T21:45:21 Focusing inward by 2516 steps...
2019-10-06T21:45:21 FITS received. HFR 0.4 @ 49678. Delta (27.5%)
2019-10-06T21:45:21 Image received.
2019-10-06T21:44:48 Capturing image...
2019-10-06T21:44:46 Focusing outward by 2516 steps...
2019-10-06T21:44:46 FITS received. HFR 1.91 @ 47162. Delta (178%)
2019-10-06T21:44:46 Image received.
2019-10-06T21:44:13 Capturing image...
2019-10-06T21:44:10 Focusing inward by 2438 steps...
2019-10-06T21:44:10 Found polynomial solution @ 17327
2019-10-06T21:44:10 FITS received. HFR 0.375 @ 49600. Delta (25%)
2019-10-06T21:44:09 Image received.
2019-10-06T21:43:36 Capturing image...
2019-10-06T21:43:36 Focusing outward by 49106 steps...
2019-10-06T21:43:36 FITS received. HFR 0.286 @ 494. Delta (16.1%)
2019-10-06T21:43:35 Image received.
2019-10-06T21:43:00 Capturing image...
2019-10-06T21:43:00 Focusing inward by 245 steps...
2019-10-06T21:43:00 FITS received. HFR 0.4 @ 49740. Delta (27.5%)
2019-10-06T21:42:59 Image received.
2019-10-06T21:42:26 Capturing image...
2019-10-06T21:42:23 Focusing outward by 185 steps...
2019-10-06T21:42:23 FITS received. HFR 0.25 @ 49555. Delta (12.5%)
2019-10-06T21:42:23 Image received.
2019-10-06T21:41:50 Capturing image...
2019-10-06T21:41:49 Focusing inward by 45 steps...
2019-10-06T21:41:49 FITS received. HFR 0.125 @ 49600. Delta (51.1%)
2019-10-06T21:41:49 Image received.
2019-10-06T21:41:15 Capturing image...
2019-10-06T21:41:14 Focusing inward by 375 steps...
2019-10-06T21:41:14 FITS received. HFR 0.636 @ 49975. Delta (18.2%)
2019-10-06T21:41:14 Image received.
2019-10-06T21:40:40 Capturing image...
2019-10-06T21:40:39 Focusing inward by 687 steps...
2019-10-06T21:40:39 FITS received. HFR 1.06 @ 50662. Delta (23.7%)
2019-10-06T21:40:39 Image received.
2019-10-06T21:40:06 Capturing image...
2019-10-06T21:40:05 Focusing outward by 500 steps...
2019-10-06T21:40:05 FITS received. HFR 0.818 @ 50162.
2019-10-06T21:40:05 Image received.
2019-10-06T21:39:31 Capturing image...
2019-10-06T21:39:26 Please wait until image capture is complete...
2019-10-06T21:03:50 Idle.

These two are obviously suspicious:

2019-10-06T21:43:36 Focusing outward by 49106 steps...
2019-10-06T21:43:36 FITS received. HFR 0.286 @ 494. Delta (16.1%)

Something went wrong to send the focuser to an absolute position of 494. That value does not reflect the previous inward focus move. The previous focus position was 49740. It looks like the 245 inward move was subtracted from that, giving 49,495 and then the number was truncated to 494.

-- Neil

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