[Jasp05 (Aaron)]

Hi guys,

Just chasing some opinions or confirmation on a few details.

My setup is as follows:

Mount: HEQ5PRO with Belt mod pier mounted.

Guiding setup: 50mm orion finderscope with ZWO ASI120mm guide camera.

Imaging Camera: Canon 1200D (unmodified)


So I'm looking to upgrade from widefield imaging with the DSLR to getting an 80mm refractor, or something like a Skywatcher 150mm F5, or a GSO 8" F5.


Now with the HEQ5, how accurate is the average persons tracking? (RMS values in arc/sec and peak to peak).

Previously my mount appeared quite bad. was around 1.3-1.5 arc/sec RMS. anything up to 4-5 arc/sec peaks.

After servicing the mount I'm getting very close to under 1arc/sec total RMS. (Dec axis is sitting around 0.5 - 0.8 RMS 90% of the time. Still got some work to do on the RA axis gear mesh as it's the weak link right now).


But based on the image scale of the above scopes with my imaging camera, they will be around 0.8 - 1.4 arc/sec pixel.

Does this mean my tracking will need to be within those limits for total RMS only? or peak to peak changes will also need to be kept under that arc/sec/pixel limit?


My understanding was that low RMS values basically meant you were going to end up with nice round stars.


But how does a peak to peak variation affect your image. (My mount currently moves 2 arc/sec peak to peak in RA but I think that's because I haven't adjusted the RA mesh properly. its a bit loose still.)

And how do you implement Periodic Error Correction while using ASCOM, EQMOD & PHD2? Or is it not necessary?

I would like to hear of other peoples setups and guiding results, and if my mount will be able to guide well enough to use a scope of 800-1000mm focal length. (I know the mount can handle these scopes, but its more I don't want to invest the money on an OTA until I know " I " can get the guiding within the required parameters to be able to use these scopes effectively for imaging.)

And with some other people's guiding results, it should hopefully give me some figures that I can aim to replicate in my mount. (At the moment I have no idea whats good. As my current imaging scale is about 3.5arc/sec pixel, so all my images have come out with decent stars regardless of the huge changes in peak to peak I was getting.)