Mike Lewis
Staff Member
OK, so after a lot of lost imaging time and effort flat black painting the inside of my QHYCFW3L filter wheel, it was sent back down with the camera to AZ to be reassembled to the OTA. That was done yesterday, and a typical check was made to make sure all systems were connected properly and that I was able to control all the gear (computer, mount, camera, filter wheel, focuser, autoguder camera) from here in CO. Because I have been sick with the flu that check was done during the day with the caps on the main scope and autoguider. Too bad we did not think to run this same test before the equipment was brought back to Colorado, because the results were categorical for a light leak (as opposed to any internal reflections...) I suppose that having the inside of the wheel flat black is still a good thing (assuming no outgassing or particulate issues over time and given the warranty of the wheel is gone) but I am guessing now that was not required.
So here is the question for any of our users out there with the QHY268M (@CRTAstro? anyone else?) - what exactly is this hole on the side of the camera for? (I cannot examine it myself as the camera is obviously back down in AZ...)
Because on my setup, with that hole uncovered in daylight (with the OTA objective cap firmly in place) I capture this in a 1 second image:
And with that hole covered with black tape under the same conditions I capture this...
What the @#@%$#@!!? I cannot believe this is supposed to work this way. Is this the desiccant tube port? I thought that was covered by a rubber cap if not used? I certainly never installed anything there. Is my camera somehow defective? camera is bolted directly to the filter wheel per the assembly instructions. I appear to be able to solve the problem with tape (at least for now) but I am quite certain everyone is not needing to resort to this hack. I HATE mysteries like this, and this one has cost me quite a lot of time and effort already. I have upwards of 40 hours of data collected on 2 targets that is corrupted by this (see previous posts...)
Anyway, will be posting this same question on CN but thought I would check here first in case anyone had any comments on what this hole is for on a QHY268M camera.
ML
So here is the question for any of our users out there with the QHY268M (@CRTAstro? anyone else?) - what exactly is this hole on the side of the camera for? (I cannot examine it myself as the camera is obviously back down in AZ...)
Because on my setup, with that hole uncovered in daylight (with the OTA objective cap firmly in place) I capture this in a 1 second image:
And with that hole covered with black tape under the same conditions I capture this...
What the @#@%$#@!!? I cannot believe this is supposed to work this way. Is this the desiccant tube port? I thought that was covered by a rubber cap if not used? I certainly never installed anything there. Is my camera somehow defective? camera is bolted directly to the filter wheel per the assembly instructions. I appear to be able to solve the problem with tape (at least for now) but I am quite certain everyone is not needing to resort to this hack. I HATE mysteries like this, and this one has cost me quite a lot of time and effort already. I have upwards of 40 hours of data collected on 2 targets that is corrupted by this (see previous posts...)
Anyway, will be posting this same question on CN but thought I would check here first in case anyone had any comments on what this hole is for on a QHY268M camera.
ML
I have a local friend here who just bought the QHY version of the camera and I talked to him. Amazingly, he had seen this plug fall out loose when he unpacked his camera, did not know where it was supposed to go, and so had laid it aside. He was no doubt going to have gone down the same rabbit hole I have been living in with this, until I explained what was up. he was able to reinstall it (and I think he taped over it too to keep it snugly in place...) For me, I had my friend do a tape only fix with 2 layers of tape: