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Hey HN, I wanted to share a video on three hardware modifications I made to my telescope that have made a night-and-day difference in my astrophotography. For a while, I felt like I'd hit a plateau with my image quality, and the issues weren't things I could fix in software. The video walks through the 'why' and 'how' of each mod: 3d printing a Bahtinov mask: To get much sharper, more consistent focus across the frame. Flocking the tube: To dramatically increase contrast by killing stray light reflections inside the scope. Adding light shield and baffle: To reduce stray light from entering my telescope and spoiling the images. I tried to show the real-world results with before-and-after image comparisons. These were all relatively low-cost, DIY-friendly projects that had a much bigger impact than I expected. Happy to answer any questions about the process or the gear here!"
My first bahtinov mask I just made out of some scrap cardboard - worked a treat.

Now I just use an autofocuser (pegasusastro focuscube), which I find gives identical results, and didn’t cost the world either (€130) - plus has the benefit that as the scope cools down through the night I’m not constantly having to stop imaging to refocus.

The flocking is interesting.

This is how Vantablack (OMG evil) and the funny cunts like Black 4.0 who fought back works... in my head. They are carbon nano-tubes.

I bought Musou Black from Japan online, it wasn't a crazy price. They do get damaged if touched and do have some hazards .

Any who, cool video, I sent it to my telescope nerd friends. It's nice to be iteratively improving things. It's a great way to save money and understand the tech before you might buy a more expensive model.

vantablack is not an option because it has a tendency to flake off and hit the glass.
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Amazing work mate! Your work makes me want to get involved with astrophotography
At the edit for the light shield, all I could think of is how he needs a light shield on that window and maybe flock his room to knock back all of that stray light from washing out his image.

From the accent, I'd say that you might have more than your share of nights where the temps dip below dew point. Adding a heater to the tube will help avoid the mirrors fogging up. It's much warmer in my part of the world, so dew points are rarely an issue. However, that extra warmth tends to make the seeing much less clear. I'm going to risk it during next weekend's dark skies. I'm spending money on it, so that pretty much guarantees cloudy conditions.

Nice video. Same exposure/stacking/filtering/conditions in the before and afters? Cave nebula shows a big difference in results
this is mine.

https://www.youtube.com/watch?v=KnmwdfzYTbU

I was having problems with focus flop on this short refractor, so i printed a sleeve that attaches to a linear bearing on the losmandy plate.

the setup has several more 3d printed changes since I recorded this. The 'car' that carries the camera is longer and has two rails now.

I'm pretty sure this is novel. Its completely eliminated focus flop without spending like 3k on a nightcrawler.

I flocked a camera lens recently (specifically, a teleconverter) - much the same process, just smaller scale. I wonder why they don't just manufacture them like this in the first place?
That's a very good question, I believe in the case of telescopes it's to offer them at a cheaper price.