Foam core is a genius idea @junker. I like how you think The first Kinograph used the diffusion from a computer monitor and it worked pretty darn well.
@johnarthurkelly thanks for addressing my original questions. Much appreciated.
Firstly, for myself and anyone following I’d just like to make sure we’re all using the same terms in the same way.
condenser - converts a divergent beam from a point source into a parallel or converging beam.
collimator - converts a divergent beam into a parallel beam, a type of condenser.
In other words, it’s a rectangle/square thing. All collimators are condensers, but not all condensers are collimators. Some focus the beam into a small point, etc.
Do I have that right? Not trying to split hairs, just making sure we don’t confuse one another.
I’m trying to condense (pen intended) what we have into a way forward. Here are some thoughts…
Sphere vs. direct.
There actually isn’t a huge difference for me in terms of easy of build. they both require printing/making parts and assembling them with electronics and mounting them to Kinograph. I’d have to attempt to do both to see the real trade-offs. Which brings me to #2…
Design factors for each:
- light should bounce multiple times before hitting diffusion
- if we need to move the light source away from the diffusion plane, a collimator could help cut down light loss in the straight-aways.
- what type of condensor we choose (if any) is largely based on the beam spread of the LED and how far the light source is from the diffusion plane.
- maybe some a few tweaks for ease of assembly, mounting, and efficient use of material
c) both direct and sphere
- inner surface should be matte white
- both should be easy to assemble, and relatively easy to build/source in small batches
- Price - as far as I can tell, there still isn’t a huge difference here either. Again, it would take more tests and hands-on experimenting before we lock down the design and therefore the costs.
In sum, the sphere is actually pretty straight-forward from what we’ve discussed. We agree it’s a good light mixer. It just remains to be seen how it would integrate with the current design. I can help there. I have John’s CAD files which I can toss into Fusion360 tonight and see how it looks.
In the direct version, it seems like taking the simplest approach and building in complexity as needed is a good approach.
SO NOW WHAT?!
I say we pool our resources and start prototyping. If we want to have John test it with the same rig for comparison, we can ship what we make to him.
If anyone wants to source the LED and driver for their own experiments, I can front the cost of a few.
I can 3D print stuff and so can @junker. I can make runs to hardware stores for other supplies as well.
What say you, friends? What do you want to build and what do you need to do it?