3 replies to this topic

[X1m]

hello guys, i have a very troubling problem. so i have a Astro tech rc6. i have made it my imaging scope, i bought a zwo oag small, not L and the upgraded focuser for it. i tested it during the day to see if i could get it in focus on a far tree and it went great, so once it became night time I went to m81 and tried to find a star there and focus, couldn't find a star there and began going all around the night sky look for a star, no matter what i did i could never find a hint of a unfocused star NOTHING. I was doing 7s exps and 70 gain. so i packed it up and did some research and i have some problems and conclusions that I would like to share. number 1. my oag is not getting enough light mixed with not very sensitive sensor. I Have a asi120mm mini that i use and my main scope is a F/9. so my thought was that with this lower end sensor and high f stop not enough light is reaching the camera. Number 2. way too out of focus, i measured my distance from oag prism and oag camera and lined it up with oag prism and main camera and got it pretty close, but maybe somehow i got it wrong? something in my setup is wrong. FIXES:: my fix for problem number one would be return my oag and get the L version and get a newer guide camera that is more sensitive. fix for number 2. well I'm not sure. ALSO i have my oag prism all the way in. i have a asi533mc pro so it does not block the sensor at all. i tried all the way sliding my sensor up and down the focuser and never found a hint of focus. My sensor is getting light, i can shine a light down the tube and it picks it up, i can even shine a flash light on a far tree and point my scope at it and my oag will pick it up. i liker in bortle 3/4 so I'm not to bad in that department. there is probably other things i have tried but forgot about at the time of typing this up.

[klangwolke]

Just so I understand, during the day you were able to focus the OAG on a tree and see the video from the 120mm installed in it. At night you were able to do the same by shining a flash light at the tree. So you could see an image from the OAG 120mm setup both of those times, right?

At that gain and exposure you should definitely be seeing stars. If you have it working during the day like you described, maybe wait a few weeks and try the moon when it’s fuller? Hopefully others have better ideas but since it’s working during the day I can only think it is a focus issue.

Anyway, you’re probably doing this, but just in case the main reason I responded was just to check if you are focusing the mini within the OAG separately also? Once you’ve got the scope focused, and the prism lined up, at night you are going to want to slowly move the mini up and down within the OAG to get the focus right.

[Eye stein]

well, I have a 120 mm camera i use for guiding and pointing also.

your back focus for the scope/533 camera should be about 55 mm.
you have me a bit confused as to what you are doing ,so here is my advise...
First..get your MAIN scope focused on that tree...then line up your finder scope w/120 mm camera with your main scope.

Until you have them lined up, don't do anything !!

Is the zwo 533 mc pro cooled? it will not work until you have it cooled (if it's a cooled camera.)
I strongly suggest you read the Quick guide that came with your 533 camera on how to set up to a scope.

good luck.
JL

[archiebald]

This is a double posting - The OP asked the same question here

 

https://www.cloudyni...am-new-to-oags/