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Sw esprit 100ed flattener distance

Equipment CCD Help Needed
6 replies•245 views
Themis Karteris avatar
Themis Karteris avatar
Hi i want some help to find the right distance. I use QHY9 + Starlight xpress FW+ OAG Starlight.
The optical window from qhy9 removed.

Someone with the same setup for help!!!

thanks  smile smile
Juan Filas avatar
Juan Filas avatar
Hi, is 63mm
Victor Van Puyenbroeck avatar
Victor Van Puyenbroeck avatar
Juan Filas:
Hi, is 63mm


Interesting, the manufacturer states 55mm. Why is the optimal distance so much larger?
Well Written Engaging
Marcelof avatar
Marcelof avatar
The distance is 55mm if you use the adapter that comes attached to the flattener or 63mm if it is removed (page 8 of the manual, available on the SW website).

The point is to cover exactly this distance taking into account the proper distances of your equipment:

Backfocus camera + FW + OAG + The filter itself* + adapters = 55mm

*for the filter a distance of 1/3 of the filter width is usually calculated.

Manual:  https://www.skywatcherusa.com/pages/support-center
Helpful
Stratos Sinathis avatar
Stratos Sinathis avatar
The right distance from the back of field flatterer to your camera sensor is 55mm. +-1mm will be ok too.
Themis Karteris avatar
Themis Karteris avatar
Hi i try to fix all the system with 55mm but it's not possible. I must take off the oag and i don't want it.
Now i have 58mm. I will try it at next new moon and i will inform you for the result with image!!!

Thanks all smile
Themis Karteris avatar
Themis Karteris avatar
Hi I do some tests with 58mm distance and is fine. It has a little in corners but is very small!!,

Thanks