2600m pro - Backfocus to Skywatcher Esprit 100? - Forums

Topic starter

Aug 8, 2023

Today I got my 2600mm pro with a 36mm filterwheel. Im not really sure if I have installed it correctly to fit my telescope...

I removed the tiltplate and screwed the camera directly to the filterwheel and then used the 16.5mm spacer to screw it on my fielflattner... but this doesnt get me 56mm backfocus? Do I need to install the tiltplate ? or have I missed something?

This is what I did, is it wrong?

or is this the correct way?

[ASI2600 Guide] 4 Connection methods to get 55mm back focus length – ZWO ASI (astronomy-imaging-camera.com)

Marc

Aug 8, 2023

you just need do use the 22.5mm extender instead of the 16.5mm you use at the moment and your good. if you only have the 16.5mm extender you have to use the tiltplate. the additional 1mm backfocus (56 instead of 55mm I guess for filter compensation) you can achieve with a 1mm spacer ring between one of the threads.

Daniel Renner

Topic starter

Aug 8, 2023

Marc:
you just need do use the 22.5mm extender instead of the 16.5mm you use at the moment and your good. if you only have the 16.5mm extender you have to use the tiltplate. the additional 1mm backfocus (56 instead of 55mm I guess for filter compensation) you can achieve with a 1mm spacer ring between one of the threads.

I tried to use the 22.5mm spacer but that didnt fit my fieldflattner...

Marc

Aug 8, 2023

make sure there is no adapter ring on the 22.5mm or the 16.5mm because they should be both M42M-M48F and there is an adapter ring included.

Tom Boyd

Aug 8, 2023

Daniel Renner:
Today I got my 2600mm pro with a 36mm filterwheel. Im not really sure if I have installed it correctly to fit my telescope...

I removed the tiltplate and screwed the camera directly to the filterwheel and then used the 16.5mm spacer to screw it on my fielflattner... but this doesnt get me 56mm backfocus? Do I need to install the tiltplate ? or have I missed something?

This is what I did, is it wrong?

or is this the correct way?

[ASI2600 Guide] 4 Connection methods to get 55mm back focus length – ZWO ASI (astronomy-imaging-camera.com)

Second way. Put the tilt plate back on the camera. Filter wheel attaches to the tilt plate directly via four screws through the back of the filter wheel and into the tilt plate.

Patrick Graham

Aug 10, 2023

The user manual for the Esprit 100ED calls for a 63mm back focus distance. Thru a combination of spacers and adaptors, you should be able to achieve this. I have a Esprit 150 ED that requires 96mm of back focus. It was a puzzle fitting the right adaptors and spacers to get that, but finally did it.

Patrick

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