Test 2 : 08/16/19
NGC7380 under 99% full moon and redzone
EdgeHD 8", Starizona Night Owl HD Prototype, ASI183MC-C, L-Enhance filter
90 - 120s subs, Unity Gain @ -10C
Note: This prototype has 3D printed plastic internal components. I am expecting to receive a better calibrated, machined version, later this week.
32bit stack, and single original .fit file, can be downloaded here for review :
Great discussion around the usability of this reducer. I do want to point out that, per the first sentence of this thread, this reducer is designed for sensors up to a 16mm diagonal. If you use a larger sensor, you will need to crop to a 16mm diagonal. It's that simple. It will not be a significant crop for the 1600/294, or any MFT type sensor, but for a APS-C or Full Frame sensor, the Celestron F7 will more than likely be a better fit. Again, it's a perfect match for the 183. Look at it like this.....as an example, with a full frame sensor attached to a EdgeHD 8, your focal length is 2032mm. Even with a Full Frame sensor attached to the EdgeHD 8, there are some areas around the edges that are not correctable with flats. It's slight, very slight, but it's there. With a Full Frame sensor, and F7 reducer, there is a significant amount of non correctable area. I've found the maximum usable space is just over the APS-C coverage area, when the F7 reducer is used. My point is this.....the F4 Night Owl HD extends the image circle, for a 16mm diagnal sensor, almost to that of the native coverage area that is equal to a Full frame sensor at F10. I estimate the FOV being roughly 2400mm FL equivalent - so although not all the way to the native 2032, it's very close. This is why I'm so interested in the F4 Night Owl HD - it gets you back to a very usable scale / FOV when using an excellent, economical cooled sensor, such as the 183 or MFT sensors. Lastly, due to the 35mm (with filter) backfocus limitation, along with the steep light angle, I doubt a OAG is possible. However, at the F4 scale, the good news is that a guidescope now is possible.
Edited by Churmey, 17 August 2019 - 12:41 PM.