Multiple Attempts Unable to Focus 120MM

pfromero

Hi all,

With ASI Studio or AllSkyEye software ( both latest versions)connected via a 4’ USB cable to a USB 3 (blue) port on my Intel NUC computer running Windows 11 and the ZWO native Windows driver (latest), I have been unable to come to focus using either the cctv lens that came with it or a 120 degree widefield lens.

I have tried and tried n terrestrial objects hundreds of feet away or objects just 10’ away, but it will not focus!

Please see attached photos..I have heard that this could be due to the fact that I am running through a USB 3.0 port, is there any reason that this might be true? Other ideas/tips/tricks?

Clear Skies,

Paul[

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johnpd

The port would have no affect. If you were having connection problems, then the port or cable could be a reason. What model camera are you using?

JohnD

pfromero

Hi John,

I am using a 120MM with version 1.6 board and the latest firmware upgrade and drivers. I am thinking to try to look through the lens with my eye and check to see if IT is clear while attempt next focus.
Thanks for giving this post some time and consideration.

Clear Skies,

Paul

Tech@ZWO

pfromero What is model of the lens and the back focus length requirements of it?

pfromero

Hi Tech Support,

I cannot tell you the model and backfocus of the two lenses. I bought my 120mm second hand, and one was the original cctv lens..or I thought.. and the second was bought by me to get a 120 degree FOV.

I tested both lenses on a QHY5II camera, and I received similar results. So, I am confident the problem is with the backfocus or lens.

Looking at my configuration in the photo above, can you recommend a ZWO lense and spacer that will work for me? My goal is to use the camera as an All Sky Camera, so a 100 degree FOV or larger is preferred. Please no plastic lenses, as it gets very sunny and relatively hot here in the summer.

Clear Skies and Sincerely,

Paul