Dither settings

Questions, tips, information and discussions about using the SharpCap Sequencer and Sequence Planner tools
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Desbarry
Posts: 61
Joined: Thu Feb 06, 2020 7:09 pm

Dither settings

#1

Post by Desbarry »

Hi reading up on this, I normally get around 0.6 to 0.8 arc pixels guiding results with my EQ6R, my current max dither step is 10 pixels based on previously having 20 which was too much movement around the frame of my ZWO533 camera. Ive read that you should try and match your settle threshold to your guiding total so I set this to just above what I was getting at 0.8 so set it to 1.5 Is this ok?

My main question is

Will my min and max settle times of 10 and 20 seconds be ok for dithers to be carried out by my mount successfully? I use ASCOM/EQ MOD with Cartes Du Ceil via laptop. Or should I increase them. Will this bugger up my guiding?

I use PHD2 with Sharpcap Pro sequencer for imaging with small less than 115mm typically 80mm refractors.
Thanks again. Derek
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admin
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Re: Dither settings

#2

Post by admin »

Hi Derek,

for the time thresholds I would advise watching the dither process a few times and seeing how long it takes (from the dither ending) until you are happy that the mount seems to have settled fully and is giving nice images on guiding frames. That gives you an idea of the minimum settle time - basically that minimum time is there to stop random image fluctuations making it look like the mount has settled almost instantly when we know that doesn't happen. For the maximum settle time, select about 2x to 3x as long as the typical settle time - this one is set to stop guiding getting stuck waiting for a settle that is not quite being registered as finished (perhaps due to random image fluctuations again).

I don't really have much experience with tinkering with the dither threshold, so less advice on that, sorry.

cheers,

Robin
Desbarry
Posts: 61
Joined: Thu Feb 06, 2020 7:09 pm

Re: Dither settings

#3

Post by Desbarry »

Thanks Robin, I will look into this next time I am out
Cheers Derek
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