November 13, 2024

Notes - 2024

As of November 13, 2024 I have downloaded Helicon, details on that elsewhere.

Lenses

I am adding a 5x Mitutoyo as well as a 20x. Jason says he uses the 5x more than any other, along with the Raynox 250 (he says he sees little difference between the Raynox 150 and 250). Storm says he takes 90 percent of his photos with the 10x. However Storm says that Travis likes to use the 20x with minimal bellows extension. Storm think the issue is that the rig Travis uses lacks rigidity (and Travis is aware of it). Storm can use the 10x with bellows extension to get similar results.

Diffusion

I need to get Lee 216 as well as 250 and 252. These come in 21x24 inch sheets and cost about $13 each.
252 is 1/8 white
250 is 1/2 white
216 is something or other
I have 216 and 250 on order.

FOV calculation

Travis invented a gadget that measures bellows extension and calculates FOV.

It is based on the VL6180X Time of Flight sensor. This measures up to 100mm (actually up to 200mm or so) with 1mm resolution. I bounces IR light off of whatever it is aimed at and has a narrow beam. I found an Amazon seller that gave me 4 little boards for $13. It is i2c.

It has a big brother, the VL53L4CM (also from ST Micro) that has a longer range (up to 1.3m), but no better resolution.


Feedback? Questions? Drop me a line!

Tom's Mineralogy Info / tom@mmto.org