Image scale

[matt]

I'm currently using my ToUcam (with 1.25" adaptor) in conjunction with a 3x Televue barlow for my planetary imaging.

I'm chasing a little more image scale with this set-up rather than jumping straight to the 4x Powermate.

I need to get the ToUcam chip a little further away from the barlow's top lens. What's the best way to achieve this?

Is there an extension tube I can buy which will fit in the barlow (1.25") and accept the ToUcam at its other end, also 1.25"???

Otherwise, perhaps someone could machine a few of varying lengths (50mm, 100mm) with a set screw at one end, for which I'd be happy to pay

Cheers

[Dennis]

Is this what you want, what you really, really want ......http://www.scopestuff.com/ss_epe2.htm

Cheers

Dennis

[matt]

I really really don't know

I just know I need a couple of extension tubes (say, 50mm and 100mm) with both ends 1.25" (I think)

I can't make sense of the products in that link.

Which of those 5 products would I need, Dennis???

Many thanks

[gbeal]

Before you get too far down the track mate, perhaps just slip a diagonal in between, and see if the image scale you get is OK, and whether you have any focus issues. OK, the quality may not be flash, but it will give you a look, and also you could roughly measure the length of the optical train.
Gary

[matt]

Unfortunately I only have a WO SCT diagonal. The one which threads straight on to the back of the 9.25.

There's no way of placing the diagonal between the barlow and the webcam

[ving (David)]

2 ways to go... bintel sell extention tubes i understand or buy a cheap barlow and pop the lens out so its completely hollow, its exactly the same thing.

[matt]

Ving

I don't think Bintel have ext tubes which are 1.25" at both ends

Might try that barlow trick.

Cheers

[Harpspitfire]

i have a plastic junk barlow i gutted out for just these cases- i dont know how much f/l it adds- but it does add something

[Dennis]

Hi Matt

What you want, what you really, really want, is one of these:

http://www.scopestuff.com/ss_eex1.htm

It fits into a 1 ¼ tube and accepts a 1 ¼ tube. I had a look in my accessory box and I have one, which I purchased from Scopestuff some time ago, and it appears to fit the description of what you require.

From their website:

“1.25" and 2" Eyepiece Barrel Extensions
Extends eyepiece or camera out from the focuser. The 1.25" extension has 2.2" setback, 2" extension has 2" setback. 2" version has a brass compression ring and two screws. Can also be used with barlows to change magnification.
Both are threaded for filters, all metal construction”.

Cheers

Dennis

[matt]

You de Man... Big D...

De Maaaaaaannnnnnnn!!!!!!!!!!!!!!