Sexy is back...

[LewisM]

After a little confusion at Starlight Xpress with the shipping of my SXVR-M25C after repair (faulty cooler, condensation in the sensor chamber), Gill sent it back DHL - it arrived just now (3 day transit). Great job from Terry - he fitted the Trius series 2 stage cooler and cleaned out the sensor chamber and resealed it.

Anyway, I need to recollimate the adjustable face plate - it's always been a bit off, but now with the f/5, it's REALLY showing up the tilt. So, oh gurus, what it the best method for aligning the tilt back to square? I was thinking to get the plate back to at least even spacing all around, and then start little tweaks, checking it with CCDInspector after each adjustment.

Or is there a better method to get the camera adjusted?

[Shiraz]

the SX website tells you how to do it.

Mine SX was misaligned after repairs, so I made up this Heath Robinson jig which worked OK when clamped to the table. beam the laser onto the chip surface and the reflected beams onto the wall. Lock the focuser and then tighten the draw tube locking collar so that it just holds the camera nosepiece while still allowing you to rotate the camera with a little force. I attached the focuser to a thick mounting block with a hole bored in it, but a thinner metal bracket would be even better.

the pattern on the wall will show the two reflections from the chamber window, maybe one from the chip cover glass and the zero order reflection from the chip surface. you can identify that one because it will be in a straight line with the two first order diffraction spots on either side of the central group. You have to adjust the faceplate alignment so that the zero order spot does not move when you rotate the camera. painstaking, but possible and way easier than just adjusting and testing with ccdi. Took me 30 minutes to align mine well enough to work OK with 4.54 micron pixels at f4. good luck.

Edit: just a tip - it is tempting to adjust everything one way, but you can end up with the grub screws hanging on only a little bit of thread and the o-ring loose enough to pass light. if you need to do a lot of adjusting, do it in both directions (this will make sense when you try it)

[LewisM]

Thanks Ray - a font of wisdom as always.

I have initially "zeroed" it using feeler gauges, so next step is in situ. Could have killed 2 birds with one stone your way, but too late ;-)

Will see how it goes. Was quite off on the FL102s at f/9, so f/5 will exascerbate that more :*)

[Shiraz]

all the best - interested to know how you get on.