This reducer - flattener is designed to work with the Altair Astro Wave Series 115mm EDT-X FPL53 102mm F7 Super ED Triplet APO.
It reduces the focal ratio from F7.0 to F5.6 speeding up imaging times, and converts the focal length from 715mm to 572mm, giving you a wider field.
It consists of two components:
A) The flattener body containing the optics, with M92 male outer thread on the telescope side and M72 female inner thread on the camera side
B) An M72 to M48 adaptor-spacer with M72 male outer thread on the flattener side and M48 male outer thread on the camera side. The adaptor has a 21.62mm optical length, to give 55mm sensor to flange distance.
Tips for use:
To connect a camera using the included M48 adaptor - spacer, please read this FAQ about reducer flattener to sensor spacing.
If you remove the included adaptor spacer, you can use any adaptor with an M72x1mm male outer thread on the telescope side, to connect to your equipment. This frees up 76.62mm of distance between the rear flange of the reducer and the sensor.
The reducer will fully illuminate an APS-C size sensor and it will work with a full-frame sensor with about 10% light reduction known as vignetting at the edges of the image-circle, and a very slight elongation of star-shapes at the very far corners. In practical use, this is barely noticeable, will be lost in framing of your image-stack, and the vignetting can be corrected with flat-frames. Fine tuning of spacing with Altair fine-tuning rings will help to control the outer corners, and if set up correctly will also compensate for the use of filters. When using Altair filters, we recommend to try adding the 0.5mm fine tuning ring first in the set.
How to attach M92 Reducer Flattener to Altair Focuser
Instructions for attaching M92 Reducer or Flattener to Altair Focuser - see pictures above:
- Loosen (but do not remove) the 2.0mm Hex Grub Screws from the rear of the focuser.
- Unscrew the rear 2? push-fit adaptor assembly to reveal the M92 inner thread on the rear of the focuser.
- The reducer can then be screwed onto the focuser for a stable fit.
- Most reducers will have a rear adaptor which gives 55mm sensor to flange spacing, so be sure to look up your camera sensor to flange distance to work out what adaptors you need.
Scope of Delivery:
Products specifications
|
Connection to telescope
|
M92 OD Thread |
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Connection to camera
|
M48x0.75 external thread |
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Working distance from the camera thread
|
55 mm from male M48 thread |
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Focal length reduction
|
0.8 x |
