Imagetrain question

Focusers, Filters, Barlows etc..

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Imagetrain question

Post by Nikonist800 » Mon Mar 25, 2019 5:21 pm

Hello guys.

I am about to put my telescope together.
I have not got everything home yet and may need to supplement with more adapters to achieve a desired backfocus of 55mm according to my dealer.

It consists of:
Sky-Watcher 80s ds pro
Sky-Watcher Focal reducer 0.85x
ZWO ASI 183MM Pro (which includes T2 adapter and M48 etc)
ZWO 8x filter wheel 1.25 "

My supplier wants to know what the total distance from the bottom of the T2 adapter on the filter wheel (which points to the telescope) to the camera's sensor to know if I need more adapters.

From what I have understood, one strives to reach a back focus of 55mm. (?)
I hope someone here can help us with some information.
Thank you in advance.

Mr Andreas

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Re: Imagetrain question

Post by Sean.Wang » Wed Mar 27, 2019 2:56 am

Firstly, does the sky-watcher 0.85x has 55mm back focal length?
If yes, follow this manual setup your imaging train: ... -55mm.html
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