Which flattener - Meade series 5000 ED80

[peter_4059]

I've had the Meade series 5000 ED80 APO triplet (f6) for a few years but have never really used it much for astrophotography. It has a reasonably flat field but there is a bit of coma at the edges. I'm wondering what flattener would be best for it?

Any suggestions?

Peter

[h0ughy]

http://www.myastroshop.com.au/products/details.asp?id=MAS-016B this one is the one i use with the 127mm version of the meade ;) it made mine pinpoint to the edge and made me very happy

[peter_4059]

I wonder if anyone has tried it on the 80mm? I found in the archives mentions from Zuts of this scope needing a flattener but it doesn't say what type he was using.

[troypiggo]

Hey mate, I've got a couple you can borrow and try. The William Optics Flattener 4 and the Orion flattener( new).

[peter_4059]

Sounds like a good opportunity Troy if you don't mind...is the the Orion one you have:
http://www.optcorp.com/product.aspx?pid=319-327-345-16697

[troypiggo]

Yep. That's it. Haven't had a clear night to test it yet. Also need to check spacing requirements.

[BlueAstra]

I use a TeleVue x0.8 focal reducer (TRF-2008) with my Meade 5000 ED80. Works really well.

[peter_4059]

I ended up purchasing the Orion after trying Troy's one with the artificial star. I also made a custom adjustable spacer and have been playing with the spacing. Here's a test image from Thursday night showing the four corners at what I think is the optimum spacing. The whole flattener/spacer/camera assembly is almost as long as the OTA now and I'm wondering if the stock focuser is up to the task - thinking I might need to upgrade to a Moonlite.

[allan gould]

That looks really excellent Peter, flat to the edges and you can't ask more than that. That ed80 certainly was a good buy and make sure you treat it to a RED moonlight!

[troypiggo]

Bluuuuuuuuuuuue!!! And 2.5" at that!