OOUK OMC 140 Mak

[Altocumulus]

OOUK, Orion Optics UK.

 

Does anyone own the 140 Mak? I'm trying to find a solution that would allow me to use this with a remote focuser. The fit for the back is AP 2.7" and SCT thread. An OVL Dual Speed 2" Crayford Focuser For SCT Telescopes should fit, I use this on my Skymax, but there's not enough space on the rear of the 140 as the focus knob gets in the way!

It currently has a Baader adapter to fit a dslr - see image. The standard eyepiece fitting, in my humble opinion, mars the quality of the rest of the assembly.

 

 

[alex_stars]

Hi,

are you still thinking about using your Mak with a remote focuser. I also have a OMC-140 deluxe and currently work on understanding its mechanics in detail.

One suggestion I would have would be to open it up from the back and remove the micrometer screw. Then you could replace that with a fixed screw to hold the primary in place and mount your OVL Dual Speed 2" Crayford Focuser to use with no obstruction.

Just a quick question. Why do you want to do that? Is your primary mirror focuser broken or does it have some mirror jump/flip when you focus?

Cheers,

Alex

[Altocumulus]

19 minutes ago, alex_stars said:

Hi,

are you still thinking about using your Mak with a remote focuser. I also have a OMC-140 deluxe and currently work on understanding its mechanics in detail.

One suggestion I would have would be to open it up from the back and remove the micrometer screw. Then you could replace that with a fixed screw to hold the primary in place and mount your OVL Dual Speed 2" Crayford Focuser to use with no obstruction.

Just a quick question. Why do you want to do that? Is your primary mirror focuser broken or does it have some mirror jump/flip when you focus?

Cheers,

Alex

Hi Alex,

 

Why? Because I remote view from indoors. This would require some motorised focus unit attached.

My OVL focuser is of the correct fitting, but the position of the micrometer screw prevents it being put in place. Your suggestion of replacing the said screw with an alternative is, certainly, possible.

 

Geoff

[Peter Drew]

I would second Alex's suggestion, an alternative possibility would be to utilise a screw on the backplate to hold a bracket mounted focusing motor that could be coupled to the micrometer barrel with a drive belt.       🙂

[alex_stars]

1 hour ago, Altocumulus said:

Why? Because I remote view from indoors. This would require some motorised focus unit attached.

Thanks, I see. Well then you actually have two options. Either remove the micrometer screw or build the focusing motor rig. Do let us know what you end up doing, that is very interesting.

Alex

[Altocumulus]

I have a simple solution, just tested manually.

An 1/2 inch extension tube with sct m/f thread.

Quick test on solar just now. Not perfect focus, as slewing was manual at the time, but enough to show a motorised focuser will work, connected to the OVL Crayford. ( It works on my Skymax.)

At 1/2 inch there's a prevention on extending the mirror screw fully outwards, but as the Mak focuses about half way in it shouldn't affect operation.

Now to source a focuser. Probably pegasus. 

 

Edited May 21, 2023 by Altocumulus

[Altocumulus]

I chose a ZWO EAF.

Less pricey than the Pegasus.

Runs on 5V, so USB to PC or Cool Cam - one less power hub to worry on.

Does the trick and tests out OK through Sharpcap.