Modified mini Newtonian for astrophotography.
Meade LightBridge Mini 114 (F450mm, f/3.95)
I bought it a while ago at a good discounted price; it's no longer sold. It's equivalent to the Sky-Watcher SKYHAWK BK 1145, though the SW has a 500mm focal length and comes with an EQ1 mount.
The telescope is small, but it has a parabolic mirror and all the adjustments of a standard Newtonian. This makes it good for practicing collimation, disassembly, and reassembly before buying a larger Newtonian.
For astrophotography, there's an issue: it has a standard 1.25-inch rack-and-pinion focuser. First, there's noticeable play and poor focusing precision; second, you can't insert a coma corrector because they're all 2-inch. Without a corrector, astrophotography isn't worthwhile, and coma is even more pronounced here compared to f/5 Newtonians due to the faster optics. It might be okay for the Moon or Sun, or planets, but the focal length and aperture aren't ideal for planetary photography. Still, I tried imaging Jupiter and Saturn, and it performed decently for such a small tube.
So, I decided to replace the focuser with a good 2-inch Crayford. I cut a larger hole, printed an adapter, and installed it. Since the focusing unit is now taller, the focal point shifted deeper into the tube, requiring me to raise the primary mirror significantly (using 100mm screws).
I also removed the dovetail that was screwed directly to the tube, as that mounting doesn't provide enough rigidity. For mounting, I got dedicated rings.
Additionally, I added mounts for a guide scope and ZWO ASIAIR.
As a bonus, I installed a ZWO EAF autofocuser to try out how it works and how convenient it is to use.
Resolution: 4000x3000 px
Scale: 3459 KB
Thank you for sharing your photos - this is exactly what this project is all about! :-)
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