Attaching camera to coma corrector?

[turboscrew]

I've been trying to figure out what do I need to connect a camera to the telescope with coma corrector in place?
The HRCC has two adapters, one T2 and one 48x1. The camera has C-mount.
Getting T2 extension tubes/rings and a T2-C-mount adapter sounds natural, but if I wanted to add barlow?

What kind of adapters are usually used?

[turboscrew]

I also asked the Finnish URSA-site, and got the idea that coma corrector is seldom used with barlow. Usually barlow is used with smaller targets that fit well in the "sweet spot" around the optical axis that suffer very little from coma.
Moon was mentioned as an exception, but still no idea how to use both barlow and coma corrector.

[Larry 1969]

You need to remove the helical focuser from the CC to attach a camera adapter.
See pg 4 here: https://www.bresser.de/out/media/23b024 ... 38290d.pdf

[turboscrew]

You need to remove the helical focuser from the CC to attach a camera adapter.
See pg 4 here: https://www.bresser.de/out/media/23b024 ... 38290d.pdf

That's why you can't get the barlow in between HRCC and camera.
The helical focuser also has some free play. It's OK in visual, but not so sure about photography.

[SkyHiker]

I presume the Barlow would go on the scope side not the camera side. So if you would insert the CC in the focuser tube you would now insert it in the Barlow. This is, assuming that you have a 2" Barlow unlike the one in your signature.

[turboscrew]

I presume the Barlow would go on the scope side not the camera side. So if you would insert the CC in the focuser tube you would now insert it in the Barlow. This is, assuming that you have a 2" Barlow unlike the one in your signature.

Yes, looks like that. And instructions for PowerMate with Paracorr actually say so.
And yes, If I come up with the need of both barlow and CC, I'll get a 2" barlow. My current one is 1 1/4" and it was the cheapest available back then - not very good.

[SkyHiker]

I presume the Barlow would go on the scope side not the camera side. So if you would insert the CC in the focuser tube you would now insert it in the Barlow. This is, assuming that you have a 2" Barlow unlike the one in your signature.

Yes, looks like that. And instructions for PowerMate with Paracorr actually say so.
And yes, If I come up with the need of both barlow and CC, I'll get a 2" barlow. My current one is 1 1/4" and it was the cheapest available back then - not very good.

The 2x GSO ED Barlow that I have is quite good for the money. It can be used at 1.5 power too if you screw off some part. For planets, 2x would get you to well over 2400x since the CC extends the focus (mine goes from 1200 to 1380 with the Paracorr). It's hard to tell if the Barlow and CC play well together optically, if you need extra rings for instance.

[turboscrew]

I recall HRCC doesn't change the focal length much - was it 6%?
I think I'll get the extensions for just the HRCC first. Then, later, I'll upgrade the barlow, and then, maybe, get the needed extensions for the HRCC - barlow combination (what needs to be changed). I think the barlow is needed first. You can get different extensions, but if the barlow, you have planned to get, is not available, ...

Yep, 6%. https://www.astroshop.eu/flatteners-cor ... or/p,47657

[Larry 1969]

Yep, 6%. https://www.astroshop.eu/flatteners-cor ... or/p,47657

Mine actually changed from 800mm to 840 (as calculated in APT) so not much gain at all. 5% according to my math...

Larry