Kstars / Ekos autofocus lock filter

[Shimonu]

I'm looking at configuring Ekos to autofocus on filter change but I'm not understanding this "lock filter" option. It sounds to me like I would choose another filter to focus the one I'm going to use.

From the indi library website:

Quote

You can lock a specific filter within the filter wheel to be utilized whenever the autofocus process is invoked. Usually, the user should select the Clear/Luminescence filter for this purpose so that Ekos always uses the same filter to perform the autofocus process.

But isn't the whole point that the focus point can be different for different filters?

[scotty38]

Not sure about Ekos but in NINA you can select a default focus filter and then create offsets for the other filters. Takes a round of manual focussing but once done any autofocus is done with the default filter and then for any filter change the offset is applied.

[Stuart1971]

9 hours ago, Shimonu said:

I'm looking at configuring Ekos to autofocus on filter change but I'm not understanding this "lock filter" option. It sounds to me like I would choose another filter to focus the one I'm going to use.

From the indi library website:

But isn't the whole point that the focus point can be different for different filters?

I think it’s assuming, that all your filters are parfocal, and most are not….so you are correct…this will not work, unless you can set offsets from that base filter, as in NINA, but I am not sure you can in Ekos….it’s been a while now since I have used it, as I moved to NINA some months ago…