3D Printed DSLR Hot Shoe Mounted Finder

[Mognet]

After some dabbling with DSLR astrophotography and aiming by guessing, I thought I'd have a go at printing my own finder. It's nothing fancy, but hopefully should do the job once the skies clear again. A quick daytime test says it should be ok

 

There are three parts to the print, and a little gluing is required. STL files are attached, and the original OpenSCad file for anyone who wants to reuse bits of it. I printed this in PLA, and allowed a tolerance value of 0.6mm in printing the thread and nut. This value might need changing for other materials.

 

Camera Sight Wheel.stl

 

Camera Sight Base.stl

Camera Sight Tube.stl

Camera Sight v1.2.scad

[Chriske]

Nice one..!
I would have tried a one strand/layer to make that crosshair, maybe even a rectangle.

[Mognet]

Good thought. I hadn't considered printing a single strand as it's not something I've attempted before. I did think about printing crosshairs at each end, but that would have involved either printed supports or an internal structure. And after a little thinking I can see how to do that. I'll do a little rework later and upload a better version of the tube

[misfit]

Looks good 

[Chriske]

2 hours ago, Mognet said:

Good thought. I hadn't considered printing a single strand as it's not something I've attempted before. I did think about printing crosshairs at each end, but that would have involved either printed supports or an internal structure. And after a little thinking I can see how to do that. I'll do a little rework later and upload a better version of the tube

Keep it simple Mognet, if you want a crosshair on both sides, print two identical parts(strand on the bed) and glue these two parts together...

[Mognet]

37 minutes ago, Chriske said:

Keep it simple Mognet, if you want a crosshair on both sides, print two identical parts(strand on the bed) and glue these two parts together...

I've kept it simple. After an argument with Cura on the minimum thickness it will generate gcode for I have a new version printing now

[Mognet]

Updated design printed and checked. Printed crosshairs are easier to see than the cotton, so thanks for the suggestion @Chriske. I've updated the original post rather than add extra files

[Chriske]

[Chriske]

Btw, I'm busy making telescopes for our youngsters at our local observatory. To make a long story short, it also contains lensless finderscope with crosshairs. But I'm going to add a(maybe two) SMD LED to lighten up these crosshairs. Might something worth to consider..
I was also planning to add a universal connector to connect these LED's to a smartphone. But apparently not all smartphones support two way power traffic, pitty...

[Mognet]

That sounds good. I think I'll just keep this one basic, and anyone who wants to adapt it in that way is free to take my design and do so

So would an SMD LED make it more like a red dot finder? I had to look it up as electronics is far from my strong point

[Chriske]

Well, I will add a resistor to lower the light intensity. Purpose is to just(barely) see the (red)crosshair against the night sky.
Never used a red-dot-finder before, so can't tell, sorry.

Nowadays on my scopes I always install a green laser instead of a finderscope. I know, many will disagree, but it's fast and accurate. And it's safe too.
In wrong hands it could damage things, Im aware of that, that is a reason why I will not install a laser on children's scopes ever.

[Mognet]

I no longer have a red dot finder to see how it works, but I've found an Instructable on making a basic RDF http://www.instructables.com/id/BEST-simple-Reflex-Sight/

Using lasers here it definitely out. I live in a town ten miles from an airport, and is frequently over flown by planes using the London airports. Added to that, there is a police station barely five minutes walk from mine. It's not worth the risk here

[Chriske]

For what it's worth.
Choosing a 15 or 20 mW laser it is not visible at all at 2 or 3 meters(yard) distance from your telescope. People standing at a distance of a few meters of my scope are not even aware I'm using a laser. Experienced observers always ask me how I manage to find objects in my field of view, there's no finderscope..? Even when I lit it they do not see a trace of laserlight at all. The trick is to lower the power of the laser until you can't see it anymore seen from sideways.
When lit I have to (literal) bend over the scope 'eyeballing' in the direction of the laser. Doing that I very clearly see the green ray 'speeding upward' the nightsky That is the only safe way to use a laser without disturbing other people or plains. BUT...! In case of mild fog the whole country can see you're using that green thing...! Needless to say I never use my scope/laser during foggy weather anyway...

Needles to say there are always idiots(sorry for that expression) using stronger lasers. During open door they show of demonstrating what 'nice' toy they just bought. One time there was that guy using a 150mW laser pointing to the stars with his toy. That kind of persons are not representative for our hobby. They should be banned from the hobby....period.