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Caution:
Do not use the Flattener 0.93X
and the Extender 1.7XR together.
Use just one at a time.
◆
MEF-3
The Micro Edge Focuser, MEF-3, is an
optionally available fine focus attachment
that permits 8 to 1 focus for critical focusing
for imaging or highly magnified viewing.
◆
Cautions for Imaging
▼Sharp Image
Use a 3-4 magnitude star in order to achieve
sharpest focus of an image. Do trial shots
with a DSLR camera to determine the best
focus of the image. You can use the "live
view" function of the camera to focus on a
star.
▼Trial Shots
Before heading to a remote place to find
darker skies, it is recommended that you
take some trial shots in your backyard. Even
in the light polluted city area, you can take
images with an exposure of one minute
or so. This will allow you to confirm the
procedures that will achieve the sharpest
images for your equipment.
▼Guided Imaging
The quality of the image will depend on
guiding. Little or no guiding error in the
process of imaging will produce very sharp
images. Play or misalignment will ruin longer
exposures. Please use a very rigid guide
scope system for long exposure imaging.
MEF-3
T-mount DX-60W
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Flattener 0.93X
When the FOA-60Q turns into the FOA-
60, the Flattener 0.93X, 2-group 2-element,
can be used. Keeping the center image
sharp as in the FOA-60 and improving the
edge aberration at the prime focus, this
can reduce a bit the focal length to 495mm
(F/8.2).
Using the Flattener 0.93X, the focal length
will be darker (f/8), but it can produce the
10 micron image (RMS-SPOT) across the
field, suitable for deep sky imaging as well
as imaging the outer corona of the total
eclipse. At the same time, it can be used
as a 500mm (f/8) telephoto lens suitable
for imaging birds and lands. To attach the
Flattener, the 50.8mm(2") is used for quick
change from visual use to imaging mode.
▼Imaging System
with the Flattener 0.93X
Effective Focal Length : 495mm
Effective Focal Ratio : f/8.2
Image Circle :
φ
44mm
DSLR Camera
Flattener 0.93X
50.8(2”) Adapter (SKY90)
