No light after tearing down c11 and reassembling it

[Chrb1985]

Hi!

After opening up my c11 and cleaning everything and reassembling it again I did a number of upgrades: Celestron dewheater ring, new camera Zwo 290mm added a barlow : Baader VIP, Baader diamond track focuser, Zwo motor for the focuser and I use Zwo filter wheel. I also installed the primalucelab eagle 4, and everything is controlled through that device.

I have order a 60mm finderscope with Zwo 174mm camera too. Tonight I was taking it out just to try it out while I wait for the finderscope and after setting up and starting Firecapture I get NOTHING but black. After a while I tried to put a flash light in front of the scope, and still not hint of light at all....

At this point I'm starting to get nervous and i tried to adjust the collimation screws thinking I might have altered the secondary mirror position when cleaning it.. in my frustration I came to think of that I removed my flipmirror when setting things back together, so I guess after removing a that big/long part from the image train the focus will be WAY off.

My thought is MABYE the telescope was so out of focus that it don't even detect light.

So my question is this: is it even possible to defocus so much that no light is detected?  or Can  the secondary mirror be so out of line that it don't point any light down to the camera.

I might add that in my frustration I took out the Zwo and pointed it a light source and the camera picked ut up. No problem..and when I gaze down the tube I can see the filter through the shaft that holdes the primary mirror. I also can swear that after puting things back together I checked that it picked up light when holding flashlight in front of the scope inside..

Im starting to think I really shouldn't have opened it up myself.. even though I followed every steps to the teeth!

Anyway, I always get real good help in here so I hope you guys can get me out of this jam too.

[Nigella Bryant]

I have a C11, yes you can put it so out of focus that it's hard to detect anything. Focus on something in the distance during daytime and at least it'll help you complete focus during the night on a star, etc. I've just cleaned mine, corrector plate removed, mirrors cleaned and put back together. Even after focusing in daytime it was still way out on Jupiter. The focusing still had several turns to reach focus. 

Edited September 22, 2023 by Nigella Bryant

[Chrb1985]

Hmmm okay. I'm really really angry at myself for both thinking of focus first.. now I have to recollinamate. Oh well.. probably needed that after the test down anyway. 

Thanks buddy will try in daylight tomorrow.

Still think it's odd though that I did not pick up ANY light at all.

Guess I'll live and learn😂🤣

I'll post after having a crack at it tomorrow

[Chrb1985]

If really like more thoughts are this to if people have other thoughts. I will triy in a few hours to have a crack at it

[GTom]

Have you checked the c11 for visual, with an eyepiece? 

[Elp]

I would have thought you should still see some sort of illumination however faint by shining a torch through. You could remove the secondary and shine a torch directly through the centre to check easily if it's the fastar type scope.

No light usually means there's some sort of obstruction. You haven't been clear on what your imaging train consists of, all the equipment above, is that all new and you've put it all together?

I don't have a scope that size but with my C6 imaging straight through via the focal reducer in the back end requires around 105mm of backspacing. If you've used a Barlow you've likely pushed the focal point further back than if it had been connected without it. Focusing with an SCT takes time going through the whole range, and adding and removing accessories even a filter makes the difference from seeing stars/donuts to seeing nothing at all.

[Chrb1985]

When I used it last time it was as follows. Baader Diamondtracker crayford -> omegon flip mirror -> Zwo filter wheel -> Zwo 290mm all of these things are thread together (M2).

Last night It was as follows: baader crayford -> one spacer( 20mm I think )with the VIP barlow inside T2 threads -> Zwo filter wheel -> Zwo 290mm 

So flip mirror is gone and vip Barlow added. I guess that part takes away 90mm and the Barlow adds about 20-30mm.

[Chrb1985]

37 minutes ago, GTom said:

Have you checked the c11 for visual, with an eyepiece? 

No but I'm gomne check today. Just not sure when I get around to it. I will post as soon as I do.

[Elp]

2 minutes ago, Chrb1985 said:

So flip mirror is gone and vip Barlow added. I guess that part takes away 90mm and the Barlow adds about 20-30mm.

Think the Barlow adds more distance than that. Being an SCT it's also incredibly "zoomed in" so high probability it's not looking at stars, with a Barlow even more so and the image will be dimmer as you've doubled your focal ratio (if using X2 barlow).

I'd try it during the day on a far off object.

[JeremyS]

As others have said, it’s probably just way out of focus. Get rough focus with an eyepiece first, then use the camera