What is backfocus?
Backfocus is a critical distance from the end of field flattener
to the camera sensor. The field flattener can provide the best
image quality if a backfocus set correctly.
We recommend you to chose our adjustable field flattener
which is designed for W.O. scope.
10
BACKFOCUS
5
5
5
10
10
10
T-mount
Sensor
Sensor
T-mount
Adjustable part
Adjustable part
For the
DSLR
and
Mirrorless Camera
user:
A
- the backfocus, The distance from the end of the flattener
to the sensor is
67.9 mm
.
B
- the distance from the T-mount to the sensor. The distance
is
55 mm
.
C
- the distance which needs to be adjusted according to the
combination of Scope-Flattener for the best image quality. In
this case, C is
12.9mm
.
C (12.9 mm) = A (67.9 mm) - B (55 mm)
For the
Astrocamera
user:
A
- the backfocus, The distance from the end of the flattener
to the sensor is
67.9 mm
.
B
- the distance from the sensor to the end of the accessories
(OGA, Filter wheel etc.) and adapters. The distance depends
on the Astrocamera and the accessories you plan to use.
C
- the distance which needs to be adjusted according to the
combination of Scope-Flattener and the Astrocamera system
for the best image quality. C = A (67.9 mm) - B
Astrocamera
Sensor
Accessories
(Filter wheel, OGA etc.)
and adapters
A
B
C
A
B
C
Adjustable part
Mirrorless
Camera
DSLR
FLAT61A
FLAT61A
FLAT61A