My turn at Printables contest

Random or Off Topic
#1

@bitingmidge has not entered this one as far as I can tell so I think I have a chance. The topic is camera-related and I just submitted a printable telescope.

Telescope mirrors are surprisingly inexpensive (maybe $30 give or take) and back in 2018 I built a Newtonian telescope using PVC and some printed parts. Now with this contest I decided to redo the whole design from the ground up and make it bigger and better, parametric, documentation, all that.

I am probably going to add on some small stuff (maybe Raspberry Pi camera mount, who knows) between now and when the contest closes, but I’m thinking by publishing a bit early I can maybe get some attention in the mean time.

Unfortunately, the full moon is a bit boring, so here’s a picture I took with a DSLR on July 8th:

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19 Likes
#2

I’m resting on my five minutes of fame Jamie! :rofl: :rofl:

Actually I’m resting on my boat in Bruges, Belgium and missing my printer, my LR2, and you guys!

Now on to serious stuff - the telescope looks fantastic - you must have a fair chance with it!

Once I clear my backlog of things to do on my return (in October) I’ll be back in touch - would love to have a crack at making one of these with my grandkids!

1 Like
#3

Due to bandwidth limitations, I haven’t downloaded any files or checked your PDF yet, but do you have links to where the hardware bits can be purchased?

That could help with the competition - the winners are often the entries with very clear documentation. Good luck with this!

#4

Nice project !
You should also post an Instructable for more visibility and hits on your Printable’s project landing page.

3 Likes
#5

Sure, these are all essentially equivalent
https://www.ebay.com/itm/363875548871
https://www.aliexpress.com/item/3256802476925049.html
https://www.amazon.com/Astronomical-Telescope-Accessories-Short-axis-Secondary/dp/B08C2XPD27

There are a bunch of sizes available. Back in 2018 the 80 mm x 800 mm was common but now they seem to be relatively rare, whereas the D114 F900 is everywhere.

I think cross-posting to Instructables is probably a good idea. Can’t hurt, and I already have all the pictures and steps written. And yeah, I’m really hoping the documentation helps a lot. It turns out the telescope itself is really easy to design, so it’s hard to stand out on the merits of the design.

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#6

Oh buddy that is Rad. The PDF is excellent. The design is versatile and looks really fun! Under $40 for the non printed parts is incredible.

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#7

I would add a few of those links to the description to highlight how inexpensive this is. Or at least mention it. Knowing nothing about telescopes I assumed the mirrors were expensive.

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#8

This is great.

You should put a screenshot or two in the pics. It is a big feature add.

I agree with Ryan that you should put those links in.

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#9

This apears to be another case where we get a bad deal this side of the 49th parallel. The stuff is much spendier here, but this is still a much cheaper option to replace the 5" reflector that I used to have.

Looks like Ill be printing a new telescope, and setting up an Arduino for a motion track system for long exposure shots.

2 Likes
#10

This is simply amazing. I’ve been keeping an inner smile ever since I came across this post! I’ve been away from my tinkering all summer, except for a few hours yesterday where I printed a - hold your breath - telescope rpi hq camera mount! I’ve got a simple refraction telescope that I’m honestly quite disappointed with. So - I’ve been thinking that a camera mount could improve it a little- which it does! The ability to adjust contrast improves the view quite a lot. It also helps that the shaking is negated.
But, I’m not happy at all with level of magnification and image quality- so I’m considering two options: building a bigger one, perhaps newtonian, or somehow upgrading the one I’ve already got. I’ll definitely coming back to this thread for inspiration and inputs!!

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#11

Really cool project, had no idea the glass could be cheap enough to make such a high quality affordable telescope. Thank you for creating and sharing. Good luck with the contest, hope to see your work on instructables, hackaday and alike.

Guessing you’re already tracking the competition :slightly_smiling_face: (Printables), their fancy thumbnail image, amazing example shots, and description describing how cheap their build is, all seem like good marketing techniques to rack up interest.

Look forward to seeing your optional automated gimbal enhancements, maybe the forum can help depending on where you want this to go. Think there’s a few folks here that know how to make stepper motor based contraptions :slightly_smiling_face:, they may help out automating tracking of celestial objects, UAPs, or unwanted invaders even :space_invader:. A federated/meshed network of cheap high quality aerial object trackers could be useful.

4 Likes
#12

And here we are on i’ables:

Not bad for just copy-pasting the documentation I already had.

Also added mention of the cheap mirrors and highlighted the documentation in the photos.

Great feedback guys, thanks!

11 Likes
#13

Weaksauce… My great Uncle Bob makes his own mirrors. :wink:

OK, he’s also proof of where I get my neuro-divergence… :stuck_out_tongue: His job at Pan-Am? Calibrating flight instrumentation.

I should emphasize that I am in no way meaning to dismiss your achievement here! Massive kudos!

4 Likes
#14

Flat mirrors are a different animal altogether. You need a reference surface for distortion free spherical mirrors.

I did hand-lap some flat mirrors once, but no idea how I’d mnage a concave one.

1 Like
#15

He has some how-to pages on how they do it. Up to 20"… Including calibrating the curvature (I think, I just scanned them).

#16

If you don’t care too much about the exact focal length, spherical mirrors should not be too bad (in theory) because the tool and the mirror naturally want to become complementary spheres, if you grind with the right technique.

In some sense a flat plate is a special case of a sphere where you do care about the focal length = infinite. As I understand it, the three-plate technique is to avoid getting a sphere when you are after a flat surface.

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#17

It’s when you start grinding your own aspherical mirrors that you know you’re obsessed.

#18

saturn_stacked

I really surprised myself with this one. And even more surprising, this is from a $6 ESP32-Cam!

This is 28 images registered, stacked up and averaged (median per pixel), and no other image processing has been applied.

esp32_cam_sensor

These small cameras have super fine pixel pitch, so the resolution will be limited by optics and not the sensor. With the lens removed and imaging directly onto the sensor, the optical quality is great, probably near diffraction limited. The sensor might have poor noise and maybe not-so-great jpeg compression, but the averaging really punches through that. I am guessing the median strategy is also good for the atmosphere, which sounds logical to me but I can’t say for sure.

I have to take a break for a bit but maybe Andromeda is next…

12 Likes
#19

When is the raspberry pi computer-controlled version coming out? I am considering building one of these, but probably would not be for a month or so. I used to have a Celestron Nextar 5 but sold it when I moved 10 years ago. I never really used it that much.

#20

I saw a bunch of telescopes with the raspi v2 camera when that came out. I was jealous. The cool thing about a digital version is being able to broadcast it over wifi to a phone or tablet so the whole family can enjoy at once. But I haven’t ever tried it.