ODK Fixing adjustment rings. 85mm diameter

all (except 5 & 10mm) have internal baffles to help remove or eliminate stray light. They take up the following in the back focal distance (BFD) £75 each [Stack of rings shown]

5mm FAR85-5

10mm FAR85-10

15mm FAR85-15

20mm FAR85-20

30mm FAR85-30

25mm FAR85-25

40mm FAR85-40

50mm FAR85-50

ODK Specified Adaptors

Adaptors down from 85mm to camera. filter wheel or adaptive optics (£150) each) using up to 15mm BFD. Email us with requirements to john@orionoptics.co.uk mark email heading ODK 85mm to camera fitting.

ODK Adaptors down from 85mm to specified

Adaptors down from 85mm to specified internal diameter 3", 2" or 1 1/4" using up 10mm in BFD (£135 each)

FAR 85 - 1 1/4 inch

FAR 85 - 2 inch

FAR 85 - 3 inch

ODK Adaptors down from 3" to 2"

Adaptors down from 3" to 2" push fit with brass compression ring using up 10mm in BFD (£115 each)

ADT 3 inch - 2 inch

ODK Adaptors down from 2" to 1 1/4"

Adaptors down from 2" to 1 1/4" using up 10mm in BDF (£25 each)

ADT 2 - 1 1/4 inch

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Please Note: The OC2 Crayford takes up 58mm of BFD. It also has 15mm of movement on the drawtube. (See example below)

Example  (BFD back focal distance)
ODK12 BFD is 218mm - (58mm OC2) - (7.5mm half the movement of draw tube) - (120mm camera equipment) = 33mm remaining for adaptors.
Adaptors to use as an example would be:
FAR85-15 and 1 x (ODK specified adaptor BFD15mm) leaves 3mm to be absorbed in focusing with the OC2.