Camera adapter & focus questions - Raspberry Pi Forums

so... i've tinkered off-n-on mounting rpi eyepiece of spotting scope - kowa tsn-661, either te-9z (20-60x zoom) or te-17hd (25x ler), if matters. kowa sells digiscoping adapters mount various digital cameras either directly to, or behind eye piece - spendy, , none of adapters seem go down small enough m12 or cs mount lens see typically used rpi cam.

assuming somehow find adapter, or pay 1 made, next step going focus. have generic camera mount assembly - rube-goldberg looking contraption designed position camera (via standard 1/4-20 mount screw) behind eye piece, coarse adjustments alignment. got set up, pi mounted in protoarmour case, never image focus regardless of positioning.

i've got cs mount adapter coming case, hopes of using other applications well... long , short of don't understand whole focusing thing, or numbers mean when i'm looking @ lenses buy. i've tried quick googling on matter, did turn wasn't helpful.

can give me (or point me towards) quick-n-dirty tutorial on need know digital camera lenses , focusing them things eye pieces or on specific point across room?

thanks,

monte

i have been struggling stuff time. i'll share i've found.

there's guy named richard kinch posts here, domain expert in stuff , you'd advised read through information @ http://www.truetex.com/raspberrypi

on alibaba can find cs/m12 zooming lenses you're looking for:

http://www.alibaba.com/product-detail/m ... 08168.html

or closer home:

http://www.m12lenses.com/3-5-8mm-f1-6-c ... -0358a.htm

problem these lenses me zoom , focus tied together. there no way focus without zooming or vice versa. still looking wide angle lens motorized focus doesn't zoom. let me know if find one!

once have lens, you'll need interface can talk whatever esoteric electronics control camera. it's been few months looking at

http://www.banggood.com/usb-to-rs485-tt ... 61537.html

and

https://www.adafruit.com/products/1749 way of controlling multiple camera motors.

once you've got camera connected, need able programmatically focus. 2 things come mind when considering you're describing.

first should remember you're not focusing on distance, you're focusing on optical finder close. sharpness , zoom should relegated scope optics.

second in general sense way focus digitally use fft calculation curves spike least. i've considered using real-time audio feedback based on fft focusing. however, there's non-trivial math required tackle stuff. check out opencv examples.

luck!

raspberrypi