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32mm or 50mm Guidescope for my setup?

William Optics Redcat 71 ZWO ASI220MM Mini Equipment Guiding
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Vinny Vent avatar
Vinny Vent avatar
Hey all, I about to pickup a Redcat 71 WIFD and in anticipation of that I already just purchased the WO 32mm Uniguide guidescope to be paired with my ASI220mm Mini. I thought this pair was fine as I have often read abou tthe 1:3 rule and the calculator on astronomy.tool showed this setup as being that 1:3 ratio. However I have now read a few others saying 1:1 is the "best" to shoot for; if that is in fact the case this would mean I need to exchange for the WO 50mm Uniguide. 

Am I understanding this correctly in that 1:1 is like the "holy grail" target to shoot for? Does this mean I should do an exchange for the 50mm? If some more context helps I will be shooting in a Bortle 8 yard with seeing conditions that generally land in the ok to poor range. Thanks in advance!
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DanRossi avatar
DanRossi avatar
You should be fine with 32mm. From Bortle 8 you may want to invest in a 1.25" light pollution filter that can also serve as an IR/UV cut filter to reduce star bloat…but try without it first.
Helpful Concise
Vinny Vent avatar
Vinny Vent avatar
You should be fine with 32mm. From Bortle 8 you may want to invest in a 1.25" light pollution filter that can also serve as an IR/UV cut filter to reduce star bloat...but try without it first.

Thanks Dan, appreciate that. And good point on the LP Filter. If I do in fact wind up needing one do you have any suggestions so I have that in my back pocket? Guessing it shouldn’t be anything to strong since it’s doing short exposures.