Schlieren Imaging Rig

I salvaged a 12" parabolic mirror for a single mirror Schlieren setup. While a spherical mirror would be more forgiving, I've had to carefully design the imaging train and pinhole projector as close together as possible to sit in the axis of collimation. A laser central to the setup allows for acceptable collimation, utilizing the reflection of the laser as you would collimate a Newtonian telescope. The light source is a 530nm green LED, matching my camera sensor's QE peak, paired with an Edmund #36-168 condenser lens and a 50µm pinhole from National Aperture. The knife edge sits horizontally, coplanar with the pinhole, at 2400mm.

I repurposed the Crayford from my 12" OTA, with its fine-focus knob allowing tremendous control of the knife edge. A 3D-printed coupling mated the focuser to a 2-axis linear translation stage.

The camera assembly was initially designed for a single carriage block, but I decided to double up to increase stability. I chose the MGN12H carriage blocks on a 250mm steel rail, bolted to a PETG-CF armature.