Question about focusing

[dmahon]

What are the best settings to use with a stepper based focuser for optimal focusing using FWHM values?

Bin 1x1 or higher?

Short (1 sec) or long (?) exposure?

[glappkaeft]

Are you focusing manually and which software(s) are you using?

If you are using the equipment in the signature I'd definitely use 1x1 binning. To measure the FWHM accurately you need to sample the seeing and your pixel scale would be much too large at 2x2. 1 second exposures are vulnerable to scintillation, I'd go with longer (5-10 seconds) exposures.