Optec Lepus Camera Mounting Plate, M48 x 075mm

Starting Price: $75.00
Price as Configured: $75.00
Brand: Optec / SKU: OP-19394-X

The Lepus telecompressor has a design back-focus distance of 100mm on-axis. Each of the camera mounting plates below are designed to maintain that back-focus for the best overall image quality and a reduction of 0.62X. Varying the back-focus distance will alter the magnification (reduction) but may introduce undesirable optical aberrations as well. It is recommended to use the Lepus telecompressor only with the recommended camera-specific mount.

Each camera mount consists of a 2.1" ID tube of various lengths and a mechanical interface such as a T-thread, C-mount, or STL thread. This ID tube fits over the camera side of the Lepus telecompressor, which features the OPTEC-2100 male circular dovetail mount. The camera mount is held securely to the Lepus dovetail using three oval point setscrews located 120 degrees apart.

Tube Length (mm) (Required)
Price as Configured: $75.00

Product Help
Need help deciding?
Tell us what you're looking for, and we’ll point you in the right direction. .

It is important that the overall back-focus distance be set as closely as possible to the design distance of 100mm on-axis. Measured from the flange at the bottom of the OPTEC-2100 dovetail, the distance works out to 105mm as shown in the PDF in the resources section. 

Most of the mechanical camera interfaces require an additional 1/10th inch or 2.5mm of back-focus. The camera backfocus distance, BF, should be known to within about 1mm for best performance and should include the thickness of any filter wheel, off-axis guider or other adapter between the Lepus and camera sensor. Use the table below to find the appropriate mounting plate for many commercially available cameras and configurations. If your camera is not listed below and you know the optical back-focus, BF, and mechanical interface (i.e. T-thread) you can determine the stock number as with the following calculation:


Mechanical Interface Flange Thickness Stock No. Prefix
T-thread 2.5mm #19392
SCT thread 2.5mm #19396
STL 2.156" thread 2.5mm #19398
C-mount 2.5mm #19399
Canon and Nikon DSLR requires T-thread
and brand specific bayonet mount. Please specify.
varies with

Next use the TUBE LENGTH value calculation above for the suffix.  For example, nearly all C-mount cameras share a 17.5mm BACK-FOCUS value. The C-mount stock number prefix is #19399 and the TUBE LENGTH would be equal to 105mm - 2.5mm - 17.5mm = 85mm.  The Optec stock number for a C-mount camera would therefore be  #19399-85 as shown in the table below.

NOTE:  The minimum tube length is limited by the height of the OPTEC-2100 dovetail plus the press-flange of the mechanical mount (usually about 0.2" or 5mm).  The standard Lepus telecompressor minimum tube length is 15mm while the Edge HD specific Lepus telecompressor is 17mm.