6 replies to this topic

[MikeCrapo]

Does anyone put a light pollution filter on their guide scope when shooting from in the city, and if so which one?

[MJB87]

Moving this topic to Equipment, for a better fit.

[AhBok]

I don’t. Filters attenuate stars a small amount and LP filters are for improving contrast between DSOs and sky background. I (actually PHD2) never have trouble finding a guide star even under the full moon. Perhaps others have a different experience, but I do not filter guide cams.

[KLWalsh]

If you have an inexpensive achromat for a guidescope and you have trouble getting small round stars for guiding due to Blue/Red/Infrared chromatic aberration, you might consider a V-block filter. That’s probably the only time I’d consider using one.

[SonnyE]

Never heard of it.

I don't, because what is the primary purpose of a guide scope and camera?

It allows your guiding program, PHD2 in my case, to find a star and lock onto it to generate guiding pulses to the mount.

A Star... Unless there is something that can block the Guide Scopes view of, or a movement that can disrupt the tracking, it just quietly holds and corrects your telescope to hold its aim.

In fact, PHD2 recommends that the focus be a little soft (meaning a little blurry) for best tracking.

My guide camera is a monochrome, meaning Black & White. Very simple.

 

So don't overthink things. Just keep it simple. No filters.

[MikeCrapo]

Thanks everyone. Just wanted to be sure.

[alphatripleplus]

If you have an inexpensive achromat for a guidescope and you have trouble getting small round stars for guiding due to Blue/Red/Infrared chromatic aberration, you might consider a V-block filter. That’s probably the only time I’d consider using one.

I've tried that due to bad chromatic aberration with the scope. Not sure it helped much with guiding in that situation vs not using the filters.