Back Focus again

[T_Clanger]

Hi,  an elderly 11002 in operation and now having issues getting good star field across the chip when attached to a Takahasi Epsilon 180D.

The manual stated back focus 15.5 +/- 0.5 mm.

Is this the mechanical distance to the CCD or is it to  the optical plane of the ccd?

Any thoughts would be welcome .

Cheers

John

[vince]

Hello John,

Sorry we didn't reply sooner! 15.5 mm +/- 0.5 mm is the optical back focus for this camera, this takes into account the thickness of the optical window glass but doesn't take into account the thickness of your filters.

Best regards
Vince