Meridian flip did not occur for first frame after timed start

Sequence Generator
1

Another one of those little observations: I started a sequence of 20-minute subs. By the time the mount had centered, camera cooled, autofocused and was tracking, there were 16 minutes to the SGP flip point. The first exposure started without flipping. I have some wiggle room on the Paramount but this could be an issue where the SGP flipping point is close to a leg clash…

[update] - the meridian flip occurred before the second exposure, by which time it was 4 minutes past the SGP flip point

2

In general, I’d say to use the “Wait for meridian” option if you don’t have much wiggle room. I believe that the Paramount needs to be past the meridian to actually perform the flip? In which case the “Wait for Meridian” may have actually worked here. Although your mount would just be sitting there for 16 minutes doing nothing. If you have the ability to track past the meridian a fair amount (say frame length (20m) plus some time for AF and other events (10m) for a total of 30m) then using the “Wait for Meridian” option is just a waste of imaging time for you.

Jared

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Jared - I’m not sure the wait for meridian option is relevant here - I was surprised that the first exposure started at all, since it took me past the flip point. When the first exposure is kicked off in a sequence, do you check for the flip point proximity, as it clearly did on the second exposure, when it was already past?

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@Jared
I’m a bit confused about the meridian flip execution. I have ‘Auto meridian flip’ enabled, set to 15 mins and normally have waiting enabled too. I noticed that if I disable ‘wait for meridian’, my sequence continued to image past the flip point and it started a 20-min exposure when it was already past the flip point by a few minutes.

I put the logfile ‘sg_logfile_20170902203146’ into a dropbox Dropbox - File Deleted

Around 22:10, I aborted the sequence, enabled ‘wait for meridian’ and resumed.

Is this normal behavior? I thought that the ‘wait for meridian’ was simply whether or not it flipped after the last exposure, or waited for the flip-point.