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Baader Hyperion 8-24mm zoom - 1-1/4 inch nosepiece

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#51 ibase

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Posted 03 December 2012 - 06:15 PM

Thanks, looking forward to the findings; pretty clouded out here too; clear skies!

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#52 Bill Cowles

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Posted 10 December 2012 - 02:59 PM

This is the adaptor that I used to reach focus. The GSO 2" balow has a slot for the locking screw, so the 2" to 1.25" adaptor sits lower than a barlow without this slot. My TV 2" barlow also has a slot so it seems most 2" barrows have this slot for the adaptor. It allow for a lens to sit around 1/2 " or so, lower and in my case it allowed for focus. The top of the adaptor is slightly recessed instead of an extension with a locking screw.

Bill

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#53 Bill Cowles

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Posted 10 December 2012 - 03:06 PM

I forgot to mention I remove the locking screw or it would not sit low enough. Since I'm using this with a Solar wedge, I need to rotate the lens for brightness control, so don't need the locking screw.

Bill

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#54 ibase

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Posted 10 December 2012 - 07:56 PM

All good info, thanks for posting! :bow:

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#55 weinerat

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Posted 10 December 2012 - 11:51 PM

For those of you with the 2.25x barlow, I'm curious about the focusing issue (i sent this not to Bill, but now am asking others). I have the 8-24 mark 3 that I've used almost exclusively on my 12" dob, but earlier this year I moved to china for a couple years and didn't want to bring the dob, so I bought a 3" table top refractor (cheap, but easy to use for planets, doubles, moon, sun). It has a very short focal length (350 mm), so with the zoom at 8 mm, I still only get 43x power. I bought an OWL 3x barlow for it, but when I add the two, I can't focus (I need the combination to sit a little deeper in the focuser, it is just out of reach, which is why I asked the question about the recessed adapter).

So this is why I'm curious. One option is I can buy the 2.25 Baader zoom and see if that solves my problem (and then I have a usable zoom when I go home for my dob or an upgraded refractor), but I would hate to do that and find out that I have the same problem. My other option is just to buy a "cheap" 3.2mm ortho for the scope.

So for those of you using the baader barlow, are you having issues with focusing in certain scopes?

#56 ibase

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Posted 11 December 2012 - 02:36 AM

For those of you with the 2.25x barlow, I'm curious about the focusing issue (i sent this not to Bill, but now am asking others). I have the 8-24 mark 3 that I've used almost exclusively on my 12" dob, but earlier this year I moved to china for a couple years and didn't want to bring the dob, so I bought a 3" table top refractor (cheap, but easy to use for planets, doubles, moon, sun). It has a very short focal length (350 mm), so with the zoom at 8 mm, I still only get 43x power. I bought an OWL 3x barlow for it, but when I add the two, I can't focus (I need the combination to sit a little deeper in the focuser, it is just out of reach, which is why I asked the question about the recessed adapter).

So this is why I'm curious. One option is I can buy the 2.25 Baader zoom and see if that solves my problem (and then I have a usable zoom when I go home for my dob or an upgraded refractor), but I would hate to do that and find out that I have the same problem. My other option is just to buy a "cheap" 3.2mm ortho for the scope.

So for those of you using the baader barlow, are you having issues with focusing in certain scopes?


Hi,

If you haven't already tried it, see if this will work. Your Owl 3x barlow has a barlow element at its bottom that can be unscrewed, just like in the pic below:

Posted Image
Barlow elements unscrewed: Top - GSO type 2" 2x barlow; Bottom - Celestron EP kit/Omni 1-1/4" 2x barlow

Remove the barlow element & screw it unto the 1-1/4" filter thread of the BH zoom. The effective power in that case would be around 1.8x instead of 3x. See if it will focus in your 3" refractor.

With regards to the Baader 2.25x barlow, I tried it with my 2.5" refractor (388mm focal length) upon reading your post. Using a standard 2" OPT diagonal with no modifications, the scope will not focus with the BH zoom (required just a little bit more in-focus racking to be able to focus). Same thing when I used a TV 3x barlow with the zoom (required even more in-focus racking than the zoom alone). But when I screwed on the Baader 2.25x barlow onto the zoom, the scope came into focus.

Hope this helps.

Best,

#57 weinerat

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Posted 11 December 2012 - 10:14 AM

Gave the unscrewing a try. The leftover element wasnt long enough to screw into the BH zoom.

So herando, what you are saying with the second part of your post is that the zoom didn't work when you slipped it onto either Barlow but did work hen you screwed it onto the 2.25 BH Barlow.

#58 ibase

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Posted 11 December 2012 - 11:43 AM

Sorry if it wasn't so clear, it's the part of the barlow with the lens that gets to be screwed unto the 1-1/4" filter thread of the zoom, like this:

Posted Image
BH zoom w/ lens-part barlow element at right

Yes, you're right about the second part:

2.5" Refractor + BH zoom = no focus
2.5" Refractor + BH zoom + 3x barlow = no focus
2.5" Refractor + BH zoom + Baader 2.25x barlow = FOCUS

EDIT: Note that in tests above, the scope +BH zoom only was very near in getting into focus; that said, I doubt if adding the Baader 2.25x barlow would fix the focus problem if the zoom only in the scope was really far off from focusing; also, test conducted was for terrestrial objects only.

But with my other refractors - 3", 4", & 6", there's no focusing problem, it's only with the small WO66mm that's finicky about focusing with the zoom.

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#59 weinerat

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Posted 12 December 2012 - 08:40 AM

your picture helps, but neither of my barlow elements fit into the 11/4 adapter of my BH zoom. It would be the same as screwing in a filter, but it is too wide.

I'm surprised your refractor wouldn't focus with the BH zoom. mine is just fine. it's only with the barlow that it just misses

#60 ibase

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Posted 12 December 2012 - 11:30 AM

In that case, the 2.25x Baader barlow will work with your Mark III zoom & refractor because using the barlow with the zoom will require a little out-focus racking than just the zoom itself.

Wondering why the barlow element in your Owl 3x barlow won't fit the filter thread of the zoom because I've read in the Owl website here that "Lens cell screws onto the bottom of the eyepiece filter thread." Am assuming it's a 1-1/4" barlow, or do you have a 2" barlow?

Yes, my small WO66mm petzval refractor that came with a 2" OPT diagonal won't focus with the zoom that's why I had to have a 2" low-profile adapter fabricated:

Posted Image

But it's worth the trouble just so that the BH zoom will work with the scope.

Best,

#61 weinerat

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Posted 12 December 2012 - 07:13 PM

The owl is 1.25". So is my old Meade Barlow. But neither are close to fitting

#62 ibase

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Posted 12 December 2012 - 09:42 PM

Oh well, same thing with the TV 2x, 3x barlows, their barlow element nosepiece won't fit the standard 1-1/4" filter thread; but the Omni/Celestron, Orion shorty and GSO's are fine for this purpose.

Posted Image
Meade 28mm SWA 5K w/2" GSO 2x barlow element

Best,






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