Artcameraman Loc: Springfield NH

Just wondering if anyone uses a IR flashlight to focus a IR converted camera.

dpullum Loc: Tampa Florida

If mirrorless the focus is done in the sensor system you did not say what camera system you have... or so it is said about my DIY converted Nikon 1. Thinking I had to have equivalent thick glass to replace remove IR and blue filter caused me problem and expense. Using the sensor direct no pre-glass solved the problem of keeping the glass surface of the sensor clean. That integrated glass is tough.

Nikon 1 has a hybrid system... "have managed the trick of integrating small sensors for phase detection autofocus directly onto the image sensor. "
https://digital-photography.com/camera/autofocus-how-it-works.php

IR flash light? A heater? No Don... he means IR flash light ~! Amazon for $20..." IR Illuminator Flashlight,LED 850nm Infrared Flashlight,Adjustable Focus Night Vision Torch Light " Problem I see with that is the 850 um light is beyond what you would see even as a red glow...[perhaps?]

Artcameraman Loc: Springfield NH

Two cameras, Fuji ISP (you may not see this listed as it's a Forensic camera) and a Phase One with a "P" series digital back. I do use a Better Light Super 6k but all focusing is done before the back (scanner) is put into the camera.