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Baader prism diagonal...which one....

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#1 HowardK

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Posted 12 October 2013 - 06:33 PM

Should i buy for an 8" Edge and Baader mkv binos for the shortest light path.

Thanku

#2 Eddgie

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Posted 12 October 2013 - 10:33 PM

See the thread I made a day or two ago.

The only configuration that will give you full aperture in the EdgeHD 8" is the following one.

Baader 10mm SCT to T2 thread adapter.

Baader T2 standard prism diagonal (the $129 one, not the $270 Zeiss, but the standard prism).

Baader Maxbright.

No other configuration available will work with full aperture.

I use the Mark V in place of the Maxbright because you can get a much larger true field, but I am only getting 7.85" of aperture.

The problem is that the 10mm Adatper is not a good choice for an SCT on a GEM because you really can't rotate the diagonal.

The 15mm SCT to T2 adapter works more like a standard SCT diagonal with a collar that locks the diagonal and allows it to be rotated like a regular SCT diagonal. 5mm Light path penalty is not enough to worry about, but if you are mounted Alt-Az, I would go with the 10mm.

Ever 10mm of extra light path you add will take .1" of aperture from your system, so it is not that you can't use other configurations. You can use whatever you like. The shorter you keep the light path though, the better the performance will be.

#3 HowardK

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Posted 13 October 2013 - 03:07 AM

Edd

Is this a 1.25" diagonal?

#4 HowardK

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Posted 13 October 2013 - 03:48 AM

Edd

If the baader prism diagonal screws onto the 10mm sct to T2 adapter which in turn screws onto the visual back then how do u lock the diagonal down in an upright position on an altaz mount?

#5 Space Dragon

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Posted 13 October 2013 - 05:39 AM

The male T2 threads which go into the T2 prism are themselves on a rotating ring, so with a bit of manipulation, it's quite easy to lock it securely in an upright position.

I've never had it slip with an Earthwin and power/filter switch and 24mm Pans, so it's safe.

#6 HowardK

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Posted 13 October 2013 - 05:53 AM

Errrr,,....
U sure?

I cannot see this rotating ring on the baader 10mm sct to t2 adapter....

Maybe i should buy .......the baader 2" locking ring to lock down the prism upright?

#7 Space Dragon

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Posted 13 October 2013 - 06:56 AM

Is this the one you're referring to....?

http://www.tringastr...ashort-t-2-m...

If so, the male T2 thread itself actually rotates but is locked down when the whole adapter is fully seated and tightened down on the SCT threads.

That way by undoing the SCT thread slightly, you release the T2 thread and are able to rotate it until it's at the right position to hold the Prism upright.
So with about 15 seconds of manipulation, the whole thing will lock securely.
It's a bit hard to explain but I can assure you it works.

#8 HowardK

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Posted 13 October 2013 - 07:17 AM

Ok...yes thats the part.

I believe you.

Thanks

#9 Eddgie

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Posted 13 October 2013 - 10:04 AM

If you are GEM mounted, I think that you are making a good choice to use the SCT Lock Ring with the 10mm SCT to T2 adapter.

The 10mm connector can indeed be tweaked to come to a good landing position but it is not at all easy to rotate to either side because the tuning ring would have to be fiddled with every time you move the diagonal.

For Alt-az, it is not necessary to rotate the diagonal, but for GEM it is essential.

And the lock ring costs you 5mm of back focus, but I think it is a far better approach than the SCT 15mm to T2 with the old SCT type locking collar. I had the 15mm and still found it less secure than I would like unless you really crank down on the collar, which makes it hard to break free.

I went to the 10mm and changed to an Alt-Az mount. I used a lot of pressure to tighten the 10mm and it is rock solid, but makes it almost impossible to rotate. And of course that is why I went to the ALt-Az Go-To mount.

Expensive though for the lock ring, but had I stayed with a GEM, this is the way I would have gone. 10mm connector with the SCT lock ring.

This is why I love Baader stuff so much. There are so many configuration options that you can tweak to your exact needs.

I now have three three Baader T2 digaonals (two T2 Prisms, on Maxbright Mirror) and a forth T2 Prism on the way.

I have put Quick COnnect rings on all of them so that I can easly move binoviewrs bweteen scopes.

Yes, it is expensive, but to me it just made more sense.

I am binoviewing now almost exclusivelly and even have a second set of Mark Vs so I can have out two telescopes and once and have Binoviewers going in each of them.

And the Baader System allowed me to do that.

I know the Maxbrights are seen as expensive for "Entry Level" binoviewers, but honestly, when coupled with the T2 Prism (or Maxbright mirror for fast refractors) it really is the best entry level binoviewr out there and worth the extra money overa WO with a cheap pair of wide field eyepeices thrown in to try to sweeten the deal (which works for them, but then everyone complains about not being able to reach focus without a 1.6 GPC... Helps them sell binoviewers though).

#10 HowardK

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Posted 13 October 2013 - 11:34 AM

Edd

You are confusing me..

I am in altaz
Spacedragon insists that the locking ring is not necessary with the 10mm sct adapter.
Read please his post
.....

#11 Eddgie

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Posted 13 October 2013 - 01:23 PM

Sorry, but maybe you did not read my post fully.

Here is what I said:

For Alt-az, it is not necessary to rotate the diagonal, but for GEM it is essential.



This means that for Alt-Az, you will be fine with just the 10mm SCT to T2 adapter for an SCT.

For GEM, you would want either the 10mm and Lock ring, or the 15mm.

But for Alt-az, only the 10mm adapter is all you need.

#12 HowardK

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Posted 13 October 2013 - 01:45 PM

Thanku Eddgie






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