Re: Fine tuning PHD2 settings for 1100 with Encoders #Guiding

Roland Christen

I would like to see a screen shot of the RA and Dec with no guide corrections. That will tell what the baseline seeing is in your area. This is the minimum that you can expect and cannot be bettered when guiding. This is fundamental in understanding of what tracking and guiding does. Without that simple test I cannot really evaluate your setup and what you can expect the rms guiding to be.

Some explanation of terms:

Seeing is simply the amount of random motion that a star exhibits due to various atmospheric effects. It is usually expressed in P-P arc seconds. Knowing that value allows setting the Min Move.

P-P is the maximum fluctuation above and below the zero point with drift component removed.

RMS is a good indicator of the amount of error that is added to the theoretical FWHM star size of your optical setup. For example if your system's theoretical resolution is 2 arc sec FWHM and the RMS is 0.5, then the star size will increase to approximately 2.5 arc sec FWHM. RMS is typically 1/4 of the P-P value.

Seeing has zero to do with light pollution or Bortle or transparency or whether you are in the country or in the middle of a large metropolis. Seeing can be superb when the sky is super hazy and you can see no stars but only bright objects like the planets and the Moon. Seeing can be particularly bad when the sky is super transparent and you can see mag7 stars with the unaided eye. Do not confuse seeing with transparency.


-----Original Message-----
From: Andrew J <andjones132@...>
Sent: Sat, Oct 9, 2021 4:00 pm
Subject: Re: [ap-gto] Fine tuning PHD2 settings for 1100 with Encoders #Guiding

Hi Roland.

It maybe that the screen shots don't show up on all clients. I can see them when logged into on my pc.


Roland Christen

Join to automatically receive all group messages.