As a part of my search for improved cadence with modest 60sec subs I am excited to see the ability to dither as part of a loop rather than for each subframe is sitting there for me to use! This awesome. Why does it matter? Consider a typical request for 6 hours of rub subs with 60s exposures. That is a total of 360 subframes. I see with an excellent Mach 1 mount that guided dither with 1sec guide exposures seems to take 20 to 30 sec either with Maxim or Phd2. So th total overhead is 150minutes added to the desired 6 hours!
if instead the rib are repeated in a loop with 3 subs for each filter and dither happens only once after each loop the total time spend dithering becomes 17 minutes rather than 150 minutes. With 120 subs per filter total dithering each 1/3rd of the time does nothing to data quality.
I think it would be a great addition to support setting up such a sequence for targets built with the Scheduler web interface. Just better leverage what we already have! At the same time allowing a plate solve position check/correction to be evoked on the same time as the looped dither would also improve overall results. Fortunately my mount tracking is excellent so though desirable the plate solve can be dropped.
If I use unguided dither instead the time savings for the entire 6 hours of data goes from about 72minutes dither overhead to 8 minutes. These are really significant time savings with clear skies being pretty precious.
best to all,
Ron