CCD Technical Information - Backfocus & Adapter Attachments

All Series IV CCD mounts are calibrated to the backfocus distances below as supplied by the respective manufacturer.  This distance is measured in millimeters from the front of the M42 Universal mount to the surface of the CCD chip.  All Series IV units are calibrated to within .001mm of factory specification.

Adapter Attachments

Note that all Series IV CCD mounts are M42 compliant with a 1mm male thread and .75mm female thread. This thread is identical to that on all Meade and SBIG cameras.  For Starlight XPress cameras, the M42  mount has both a male and female 1mm thread which conforms to their specification (with the exception of the new SXV models which have a .75mm female thread ring on the CCD). 

A nosepiece is included with each Series IV for all models. These are manufactured to match the flange thickness of the manufacturer's original nosepiece.  Thus, removing the nosepiece we include, you can also attach the Series IV directly to other accessories you are using since the backfocus distance is preserved.  This is possible since the modular mount threads on the Series IV are identical to those on your CCD.

 As a rule, use the very same type of adapters on the Series IV and on your CCD camera  to preserve the backfocus distance.  The easiest way to do this is to just pretend that the Series IV is your camera and set up the very same way.

 For other accessories such as CFWs, AO7s, etc.,  STI  offers special adapters  to match the additional backfocus distances these add to your set up.  If you let us know exactly what accessories you are using, we can easily manufacture precision extensions and adapters to your specification.  This will guarantee a perfect swap-in, swap-out of the Series IV on your scope.  Many different combinations of accessories are possible, and we have seen nearly all of them.  If you think you have a very weird set up, you'll probably be surprised that we already have a solution waiting.  Just email us!

                      Backfocus Distances of Astronomical CCD Cameras(mm)                                                          

Meade	416XTE	201XT	208XT	216XT	1616XTE
bf	12.90	9.50	10.00	10.00	12.90
S.B.I.G.	ST-4	ST-5 STV	ST-6	ST-7	ST-8	ST-9/10	ST-237
bf	1.016	16.26	16.26	23.36	23.36	23.36	16.76
Starlight	MX5	HX5	MX7
bf	17.5	17.5	16.5
Apogee	AP1	AP2	AP260	AP7	SPH2	KX1/2	KX4
bf	29.46	29.46	29.46	29.46	29.46	17.53	24.89
Genesis	3200
bf	18.03
FLI	29.89