ZWO OAG with Esprit?

[SB]

Hi Folks,
Is anyone using ZWO OAG with SW Esprit? I'd be keen to know the performance of the OAG pros and cons. I have the Esprit 100.

Thanks

Chris.

[that_guy]

I'm using the zwo oag with the helical focuser and asi120mm mini. It works a treat! I also have the 100ED.

[SB]

Hi Tony,
Thanks for the feedback. I have a ZWO filter draw with Duo-band filter (used depending on the target), do you place your OAG in front or behind any filters you use (i.e OAG next to the camera or in front of a filter)?

Thanks

Chris

[that_guy]

In front of the filterwheel. You don't want to be guiding through a narrowband filter aha.

[that_guy]

I would highly recommend getting the helical focuser and one of their mini guide cameras. One of the biggest challenges with oag is focusing them. With the helical focuser, it's as simple as turning it rather than having to move the whole thing up and down with your hand.

[Astronut07]

Hi Chris

As Tony has stated you need to have the OAG in front of filter drawer
I have the ZWO OAG ( with helical focuser ) & ZWO 120 mono mini guide camera connected to ZWO filter drawer connected to ZWO1600MC
I have the imaging train connected currently to my WO132 but I can transfer the whole imaging train between other scope when needed

Attached is a image of current configuration & too answer your question this configuration has worked extremely well for me

Sometimes a picture tells a thousand words

Hope this helps

[SB]

Thanks Ben and Tony
That’s very helpful.

When I insert the duoband filter into my filter draw it means re-focussing. For your setups would I be correct in saying that for each filter (or filter removal) the focus needs to be altered on the scope AND the OAG?

Thanks

Chris

[Astronut07]

Chris

From my own experience & filters I do have to refocus on each filter change
I have a label on scope that indicates where my course focus is & then I fine focus once I start to image

Cheers

[that_guy]

I have an autofocuser that focuses everytime there's a filter change and at every hour. Especially with refractors you'll see focus shift in different colour filters

[SB]

Hi Tony
Thanks. I imagine that you would have to manually alter the OAG focus each time for each filter change (as it is in front of the filter)? If so, having an EAF on the OAG (if one exists) would be good!

Chris

[brisen]

Hi Chris

I also use an OAG with an Esprit and once the OAG is focused I don't change the focus of the OAG, the focus will change slightly when you change filters but guiding does not need a perfectly focused star to guide accurately as the guiding software will determine the centroid of the star being used. Sometimes a slightly defocus guide star works more effectively.

Brian

[RugbyRene]

Brilliant!! I'd never thought of using an OAG on a wide field refractor. I'd always heard it used on a long focal length SCT.

I've got the OAG, so all I need is the helical focuser. Guess I'm off to Bintel today. :)

Rene

[Astronut07]

Rene

As I have stated in earlier post I use my OAG imaging setup on my WO132mm, WO110mm and also on TS Optics71mm refractors

Have not had any issues at all

Ben