2/3rd method of focus with SGP

[AlistairW]

Hello,

I often hear mention of the 2/3rds focusing method that suggests not focusing on a central star, but rather on one 2/3rds the way from the centre. Obviously this can be done manually with a B mask, but I was wondering has anyone managed to do this with software packages. For example will SGP allow for this scenario?

Alistair

[billdan]

I think the 2/3rds method only applies if you have a lot of field curvature. Like a Frac without a field flattener.

 

[sloz1664]

SGPro uses the image to average out the focus so does not rely on focusing on a single star. So 2/3rds is not an option.

Steve