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Best Diagonal for 2" Eyepieces in an EdgeHD 800?

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#1 Sarkikos

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Posted 21 August 2014 - 10:23 PM

I recently purchased an EdgeHD 800. I'm mounting it on a NexStar SE 6/8. I want to minimize the light path behind the rear opening when using a 2" diagonal, not only to allow the diagonal to clear the mount when looking at zenith, but also to optimize the clear aperture.  I already have a Baader T2 1.25" Prism Diagonal and 10mm SCT-T2 adapter for 1.25" eyepieces and binoviewing.  At this time I'm not interested in binoviewing with 2" eyepieces or binoviewing deep sky at all.  But I would like to minimize the light path when utilizing a 2" diagonal and 2" eyepieces.

 

So far I've been able to clear the NexStar mount when the OTA is pointed at zenith, but the diagonal misses the mount by a mere 3mm! Too close for my comfort at a dark site. This is with the OTA pushed up as far as possible in the NexStar saddle.  To do this, I removed the 2" nosepiece from an Orion 2" Dielectric mirror diagonal and attached the diagonal to a 10mm Baader SCT-T2 adapter via a T2-2" adapter ring.  

 

I'd like to have a 2" diagonal setup that would give me more clearance between the EdgeHD 800 OTA and the NexStar mount.  I'm  thinking about this Baader T-2 Maxbright 2" Mirror Diagonal.  http://www.optcorp.c...onal-2inch.html  I would attach it to the rear opening of the EdgeHD with my Baader 10mm SCT-T2 adapter.

 

On the other hand, the Baader T-2 Prism Diagonal that I already own has a 34mm clear aperture. The Baader T2- Maxbright 2" Mirror Diagonal has a 35mm mirror surface, only 1mm larger.  Couldn't I use the Prism Diagonal for 2" eyepieces?  Why would I need the T2 Maxbright or any other diagonal besides the Baader T2- Prism Diagonal I already have?

 

It doesn't seem, though, that the T2 Prism Diagonal is recommended for 2" eyepieces The product description includes this:

 

 

A Note from Baader: "We do not recommend this housing for 2" eyepieces. The clear aperture is 34 mm. Only at the telescope side you can choose either a 2" (#16) or 1.25" (#14) nosepiece. At the eyepiece side we only recommend 1.25" eyepiece holders.

 

 

And yet another product description for the same Baader T2 Maxbright Diagonal says that it is a 1.25" diagonal, not a 2".  http://www.highpoint...-diagonal-max-1  What's going on here? I don't want to buy a diagonal that might vignette some of my wider field 2" eyepieces.

 

Mike


Edited by Sarkikos, 21 August 2014 - 10:58 PM.


#2 dotnet

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Posted 21 August 2014 - 11:37 PM

I don't think it matters whether you use the T2 Mirror or the T2 Prism, both will vignette with wide enough eyepieces (say, upwards of 30mm and 65 degrees). The T2 mount itself is the bottleneck, it lies in between 1.25" and 2". If you stick to eyepieces with suitably small field stops you should be ok.

 

Depending on the baffle size of the EdgeHD 800 it may not matter at all, the baffle may start to clip the field even before the T2 aperture does, I don't know...

 

Cheers

Steffen.



#3 Hesiod

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Posted 22 August 2014 - 06:24 AM

Maybe you could look at this: http://www.baader-pl...ion/s09/s09.htm (5th from top, Nexstar Locking ring 2"). The ring requires a star diagonal whose nose is screwed via a SC thread, like the good and pricey 2" Baader mirrors, or this way cheaper and more humble one, which I own (is sold also under Orion brand): http://shop.tecnosky...Kdiag90&Score=1



#4 Sarkikos

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Posted 22 August 2014 - 06:54 AM

I think something that can easily lead to misunderstandings is that often a diagonal is referred to by merely something like "Baader T2."  However, there are several Baader diagonals that could be called a "T2."  In some of the older threads here on CN, the posters too often get into the easy habit of not being specific. The context is lost during the course of the thread, and the result can be confusion on the part of readers. 

 

Please, everyone try to be specific in this thread. Just a friendly request before ambiguity raises its ugly head.

 

:grin:

Mike


Edited by Sarkikos, 22 August 2014 - 07:19 AM.


#5 Sarkikos

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Posted 22 August 2014 - 07:13 AM

I don't think it matters whether you use the T2 Mirror or the T2 Prism, both will vignette with wide enough eyepieces (say, upwards of 30mm and 65 degrees). The T2 mount itself is the bottleneck, it lies in between 1.25" and 2". If you stick to eyepieces with suitably small field stops you should be ok.

 

Depending on the baffle size of the EdgeHD 800 it may not matter at all, the baffle may start to clip the field even before the T2 aperture does, I don't know...

 

Cheers

Steffen.

 

This is a good point. According to Eddgie, the baffle size of the EdgeHD 800 is 37mm or 42mm, depending on exactly where you measure it. One inch inside, the inner baffle itself is 37mm, but then it opens out to 42mm.  T2 is 42mm.  So using T2 threaded diagonals should not make the situation any worse.

 

However, what eyepieces have a field stop larger than 42mm? The Nagler T5 31 has a 42mm field stop. It should not vignette in these T2 diagonals. An AT Titan-II ED has a 45mm field stop. It's on the border.  When the incoming light cone reaches the field stops of these eyepieces, shouldn't the cone be narrow enough that there is no vignetting?

 

The AFOV of the eyepiece per se shouldn't matter. It's the size of the field stop that's important. My ES 100 14mm has a field stop that's only 24.5mm. My Ethos-SX 3.7 has a 110 degree AFOV but only a 7mm field stop.

 

Mike


Edited by Sarkikos, 22 August 2014 - 07:24 AM.


#6 Hesiod

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Posted 22 August 2014 - 07:19 AM

Sorry, I make apology.

 

The "T2" are only one of the Baader's diagonal "line", 1,25" models* which were planned for their binoviewers; the Maxbright line of 2" high quality mirrors does not have a T2 thread, but an SC thread instead, albeit Baader offer the right adapters (they seems to love adapter at least as Takahashi engineers...).

 

 

 

*among them there is the notorious so-called "Zeiss" prism, which have a free aperture of 36mm and added some confusion because it can enlighten the smallest 2" eyepieces, and a Maxbright 1,25" mirror. The T2 has all a black housing, while the 2" Maxbright were usually white (but the 2" prism is black too...)



#7 Sarkikos

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Posted 22 August 2014 - 07:22 AM

No need to apologize. I think a lot of the confusion among these products is brought on by Baader themselves as well as by the vendors of their products.

 

:grin:

Mike


Edited by Sarkikos, 22 August 2014 - 07:23 AM.


#8 Sarkikos

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Posted 22 August 2014 - 07:42 AM

Hesiod,

 

It appears that the 2" NexStar Locking Ring would allow me to directly connect the SCT rear opening on my EdgeHD to 2" diagonals that have 2" threading with nosepiece removed.  This should work with my Orion 2" Dielectric Diagonal.  I wonder how much more clearance this adapter would give me than the Baader 10mm adapter I already have.  The 10mm adapter only gives me 3mm clearance between the diagonal and the NexStar mount.

 

I think I'm going to order one of these NexStar Locking Rings!

 

Mike



#9 Eddgie

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Posted 22 August 2014 - 08:21 AM

I'd like to have a 2" diagonal setup that would give me more clearance between the EdgeHD 800 OTA and the NexStar mount.  I'm  thinking about this Baader T-2 Maxbright 2" Mirror Diagonal.  http://www.optcorp.c...onal-2inch.html  I would attach it to the rear opening of the EdgeHD with my Baader 10mm SCT-T2 adapter.

 

Why not elimiante the 10mm connector and go direclty attached using the SCT Locking Ring?

 

This will give the absolute shortest 2" light path possible with an SCT.  There is no way to be shorter.  The diagonal screws directly on to the rear port of the SCT.

 

And the giant advantage that it has over the 10mm SCT to T2 is that the lock ring makes it easy to rotate the diagonal.  The 10mm SCT to T2 does not make it easy to turn the diagonal.  Not that this is usually needed on and alt-az mount, but if you ever change mounts, it can be a good investment just for that reason. 

 

You won't get  a shorter light path in a 2" diagonal, and the locking ring is a far better way to mount than using the 10mm adapter.

 

I am not positive about clearance, but it seems to me that someone did post that they used the Baader directly attached to an EdgeHD and that it worked fine.

 

http://agenaastro.co...nal-to-sct.html


Edited by Eddgie, 22 August 2014 - 08:21 AM.


#10 Eddgie

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Posted 22 August 2014 - 08:28 AM

And a note about the above.

 

This is probably the only 2" diagonal that lets the standard SCT (other than the C14) work at anyting close to stated focal lenght.

 

I would guess that the reason that the standard SCTs were shipped with a 1.25" visual back and a 1.25" prism diagonal is that this is the only configuration that allows a C8 to work at 2030mm (or as close as one can get anyway).

 

Even changing to a 1.25" mirror diagonal would increase the focal lenght to 2060 to 2070mm.

 

Using 2" visual back and 2" diagonal might further increse the focal lenght to as much as 2200mm or more, depending on the diagonal and visual back.

 

The light path lenght though the Baader 2" diagonal when mounted directly to the rear port is likley about 58mm to 60mm, and the added lenght of the eyepiece holder will add about 25mm or 30mm.  This means that vs a standard 1.25" visual back and prism diagonal, you are only about 25mm longer, so focal lenght is going to be closer to 2100mm. 

 

For those wanting the widest, best illuminated true field out of their SCTs with a 38mm rear port, the Baader mounted directly is the absolute shoretest 2" light path that I know of.  It will be at least about 75mm and parhaps as much as 125mm shorter than with most 2" visual backs and standard 2" diagonals.

The old fashined "SCT" diagonal was actually better suited to SCTs becuase it had a very short nose connection.  I think these were about 15mm.    This is between 15mm and 20mm shorter than the typical 2" visual back, and that translates into between 45mm and 60mm of focal lenght.

 

But not as short as the Baader directly mounted to the rear port.    Again, as best as I know, you can't get a shorter light path.

 

And last, this..  For someone wanting to use a focal reducer with their SCT, this is the most ideal way to do it.   The locking ring would be mounted to the rear port, and the focal redcuer would be screwed into the diagonal face.   This will give the least apeture reduction possible when using a focal reducer on an SCT.

 

I don't mono-view anymore with my EdgeHD 8", but if I did, the Baader with lock ring would be the diagonal I would go to.


Edited by Eddgie, 22 August 2014 - 08:48 AM.


#11 Hesiod

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Posted 22 August 2014 - 08:53 AM

The stated light path for Baader Maxbright 2" is around 10 cm, without "nose" and with a 2" eyepiece Clicklock eyepiece holder (http://www.baader-pl...clicklock_zeiss, look at the "M68" version).

I do not know if Celestron own 2" SC mirror is actually shorter.

Anyway, I have a vanilla C8 and judged the view with a 2" set too messy for a small gain in tfov; with an Edge model instead thing could have been different.



#12 RAKing

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Posted 22 August 2014 - 09:03 AM

Mike,

 

There are a few options for you to consider - and you should have been hanging around the Celestron SE Forum a few years ago! :lol:

 

First of all, I took care of the clearance issue by simply stacking another dovetail to the regular one. This allowed me to slide the OTA farther forward on the SE mount and eliminated any clearance issues.  This mod is known as "Ron's Rail".  :bigblush:

 

 

Attached File  8SE_Rail_022309.JPG   48.28KB   3 downloads

 

 

Second, I know Ed has done a lot of research into this, but I never had any issues with simply using a regular visual back on my C8-HD - and I also used a regular 2 inch diagonal. There was never any hint of vignetting or of aperture loss, etc. The visual back I ended up liking the most on my C8-HD was the Baader ClickLock.  It worked fine with 2 inch eyepieces, 1.25 inch eyepieces, and my Baader Mark V binos.

 

 

Attached File  C8_MkVb_022710.JPG   48.61KB   2 downloads

 

 

I enjoyed my C8-HD for several years. It is now with a friend in Arizona and is still doing a great job for him, too.

 

Cheers,

 

Ron

 



#13 Eddgie

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Posted 22 August 2014 - 09:46 AM

I tested my own EdgeHD 8" in a configuration similar to the one you show, with a 2" nose, 1.25" Standard Prism, and Mark V Binoviewer.

 

Measured apeture was 7.6".

 

True, this is not easy to see.  It represents only about a 18% difference in image brightness and only about a 1.5% obstruction increase. 

 

I felt that I could see the difference.. More so than changing from this or that Plossl to a "Planetary" eyepeice, but I am the first to admit that the difference is quite subtle.

 

I guess it only matters if it matters, but to me, using a scope at a higher power and narrower field, and with less perfect optical correction (increase in back focus can induce spherial aberration) is slighly less desirable than using the same scope at lower power with a wider field and better correction.

 

Every little bit helps.

 

Just my opinion of course.

 

But for the OP, if the desire is to use 2" eyepeices, there really is no better game in town than direct connection of the diagonal using the SCT lock ring.  Widest field, lowest power, and best optical correction.   While it may be only subtle, in telescopes and things like eyepeices, it seems that many strive for perfection, and the difference between pretty good and perfect is often only a matter of subtle improvements.



#14 RAKing

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Posted 22 August 2014 - 08:16 PM

I tested my own EdgeHD 8" in a configuration similar to the one you show, with a 2" nose, 1.25" Standard Prism, and Mark V Binoviewer.

 

Measured apeture was 7.6".

 

True, this is not easy to see.  It represents only about a 18% difference in image brightness and only about a 1.5% obstruction increase. 

 

I felt that I could see the difference.. More so than changing from this or that Plossl to a "Planetary" eyepeice, but I am the first to admit that the difference is quite subtle.

 

I guess it only matters if it matters, but to me, using a scope at a higher power and narrower field, and with less perfect optical correction (increase in back focus can induce spherial aberration) is slighly less desirable than using the same scope at lower power with a wider field and better correction.

 

Every little bit helps.

 

Just my opinion of course.

 

But for the OP, if the desire is to use 2" eyepeices, there really is no better game in town than direct connection of the diagonal using the SCT lock ring.  Widest field, lowest power, and best optical correction.   While it may be only subtle, in telescopes and things like eyepeices, it seems that many strive for perfection, and the difference between pretty good and perfect is often only a matter of subtle improvements.

 

Ed,

 

Are you sure about these numbers? 18 percent is hardly "subtle" - most of us can tell when we lose close to 20 percent of the brightness. The drop from 8 inches to 7.6 would cost me about 0.1 magnitude in reach, but I know that my atmospheric conditions can have a lot more effect on what I can or cannot see than a tenth of magnitude. It's been a while since I had the C8, but it was a great little scope and I used it with lots of different combinations at the back end.

 

But anyway, I don't want to argue with your numbers. Personally, if I was looking for 'perfection' or for something showing a wide FOV, I would not be looking for an SCT. :)

 

Cheers,

 

Ron



#15 Sarkikos

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Posted 22 August 2014 - 08:47 PM

 

I'd like to have a 2" diagonal setup that would give me more clearance between the EdgeHD 800 OTA and the NexStar mount.  I'm  thinking about this Baader T-2 Maxbright 2" Mirror Diagonal.  http://www.optcorp.c...onal-2inch.html  I would attach it to the rear opening of the EdgeHD with my Baader 10mm SCT-T2 adapter.

 

Why not elimiante the 10mm connector and go direclty attached using the SCT Locking Ring?

 

This will give the absolute shortest 2" light path possible with an SCT.  There is no way to be shorter.  The diagonal screws directly on to the rear port of the SCT.

 

And the giant advantage that it has over the 10mm SCT to T2 is that the lock ring makes it easy to rotate the diagonal.  The 10mm SCT to T2 does not make it easy to turn the diagonal.  Not that this is usually needed on and alt-az mount, but if you ever change mounts, it can be a good investment just for that reason. 

 

You won't get  a shorter light path in a 2" diagonal, and the locking ring is a far better way to mount than using the 10mm adapter.

 

I am not positive about clearance, but it seems to me that someone did post that they used the Baader directly attached to an EdgeHD and that it worked fine.

 

http://agenaastro.co...nal-to-sct.html

 

 

OK, slow down now and let's get our adapters and diagonals straight before we start throwing them around willy-nilly.

 

Is this SCT Locking Ring the same adapter that Hesiod linked to his post above?  From the description in his link, I thought it would connect the SCT rear opening to 2" threading that is on some 2" diagonals when the nosepiece is removed.  In other words, I thought the SCT Locking Ring had SCT female threads on one side and 48mm male threads on the other.  In that case, I could have used it to connect my Orion 2" Diagonal - without nosepiece - directly to the rear opening of my EdgeHD 800.

 

However, after reading the descriptions on the Agena website, if this is the same SCT Locking Ring - which apparently it is - it would attach the Baader Clicklock Diagonal without nosepiece directly to the rear opening of an SCT.  The Baader Clicklock Diagonal has SCT threads. So the SCT Locking Ring would be joining SCT to SCT. At this point in time such a ring would not help me at all, since I don't have a 2" Diagonal with SCT threads.

 

Sure, I'm interested in the SCT Locking Ring if it can give me the shortest light path in a 2" diagonal. But let me get this straight. In order to use the SCT Locking Ring, don't I need a 2" diagonal with SCT threads under the nosepiece? 

 

Mike



#16 Sarkikos

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Posted 22 August 2014 - 08:57 PM

And a note about the above.

 

This is probably the only 2" diagonal that lets the standard SCT (other than the C14) work at anyting close to stated focal lenght.

 

I would guess that the reason that the standard SCTs were shipped with a 1.25" visual back and a 1.25" prism diagonal is that this is the only configuration that allows a C8 to work at 2030mm (or as close as one can get anyway).

 

Even changing to a 1.25" mirror diagonal would increase the focal lenght to 2060 to 2070mm.

 

Using 2" visual back and 2" diagonal might further increse the focal lenght to as much as 2200mm or more, depending on the diagonal and visual back.

 

The light path lenght though the Baader 2" diagonal when mounted directly to the rear port is likley about 58mm to 60mm, and the added lenght of the eyepiece holder will add about 25mm or 30mm.  This means that vs a standard 1.25" visual back and prism diagonal, you are only about 25mm longer, so focal lenght is going to be closer to 2100mm. 

 

For those wanting the widest, best illuminated true field out of their SCTs with a 38mm rear port, the Baader mounted directly is the absolute shoretest 2" light path that I know of.  It will be at least about 75mm and parhaps as much as 125mm shorter than with most 2" visual backs and standard 2" diagonals.

The old fashined "SCT" diagonal was actually better suited to SCTs becuase it had a very short nose connection.  I think these were about 15mm.    This is between 15mm and 20mm shorter than the typical 2" visual back, and that translates into between 45mm and 60mm of focal lenght.

 

But not as short as the Baader directly mounted to the rear port.    Again, as best as I know, you can't get a shorter light path.

 

And last, this..  For someone wanting to use a focal reducer with their SCT, this is the most ideal way to do it.   The locking ring would be mounted to the rear port, and the focal redcuer would be screwed into the diagonal face.   This will give the least apeture reduction possible when using a focal reducer on an SCT.

 

I don't mono-view anymore with my EdgeHD 8", but if I did, the Baader with lock ring would be the diagonal I would go to.

 

And the Baader Diagonal that you are talking about that would allow the shortest light path when used with the SCT Locking Ring http://agenaastro.co...t-diagonal.html is the Baader 2" Clicklock Mirror Star Diagonal http://agenaastro.co...r-diagonal.html , correct? That was the diagonal Manish talked about in his article at Agena.

 

In the OP I was talking about Baader T-2 Maxbright Mirror Diagonal - 2" http://www.optcorp.c...onal-2inch.html.  Unfortunately, this diagonal is sometimes called a 2", other times called a 1.25", which confuses matters even more.

 

Sorry, but I've seen these types of threads (pun intended) lose context very quickly, so that soon it becomes unclear exactly what adapter or diagonal or other accessory is being discussed.  Baader makes a heck of a lot of different diagonals and adapters.

 

There might be difficulties with an EdgeHD when using a focal reducer. Don't they need a special FR made for the EdgeHD's, costing about $300?  Would they be compatible optically when set up with the SCT Locking Ring?  But the added expense of a special EdgeHD FR is not on my short list at this time.  First I want to see how my EdgeHD 800 will perform without FR, using some nice 2" eyepieces like the Nagler T5 31.

 

Mike


Edited by Sarkikos, 22 August 2014 - 11:26 PM.


#17 Sarkikos

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Posted 22 August 2014 - 09:22 PM

Mike,

 

There are a few options for you to consider - and you should have been hanging around the Celestron SE Forum a few years ago! :lol:

 

First of all, I took care of the clearance issue by simply stacking another dovetail to the regular one. This allowed me to slide the OTA farther forward on the SE mount and eliminated any clearance issues.  This mod is known as "Ron's Rail".  :bigblush:

 

 

attachicon.gif8SE_Rail_022309.JPG

 

 

Second, I know Ed has done a lot of research into this, but I never had any issues with simply using a regular visual back on my C8-HD - and I also used a regular 2 inch diagonal. There was never any hint of vignetting or of aperture loss, etc. The visual back I ended up liking the most on my C8-HD was the Baader ClickLock.  It worked fine with 2 inch eyepieces, 1.25 inch eyepieces, and my Baader Mark V binos.

 

 

attachicon.gifC8_MkVb_022710.JPG

 

 

I enjoyed my C8-HD for several years. It is now with a friend in Arizona and is still doing a great job for him, too.

 

Cheers,

 

Ron

Hi Ron,

 

Yes, I've read several threads about Ron's Rail. It's a great idea. But I don't have a drill press and I'm allergic to drilling holes in dovetails with a hand drill. I break out in a sweat just thinking about it.. :grin:  I want to try something like Ron's Rail, but with off-the-shelf stuff and no drilling. I ordered a 7" slotted dovetail from Astronomics. Unfortunately it's on back order - I wonder why? :thinking: - and there's no telling when I'll actually get it.

 

In the meantime, I'm working on making the light path behind the rear opening as short as possible.  I have my EdgeHD 800 on a NexStar SE 6/8 mount, so I need as much room as I can get between the OTA and the mount.

 

Mike



#18 ewave

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Posted 22 August 2014 - 09:33 PM

Mike

The best setup for you would just be to get the 2" Baader Clicklock diagonal + the locking ring:

read more here:

http://www.alpineast...nals.htm#Max-2c

 

clear skies



#19 Sarkikos

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Posted 22 August 2014 - 11:30 PM

Yes, that's what I'm thinking. 

 

But could someone please tell me exactly what is the threading on both sides of the Baader 2" Clicklock Diagonal?  The product descriptions are not very clear on many of these websites. Seldom is anything described in simple specs without a lot of verbiage and advertising patter.  Here is an example of clear-as-mud verbiage from Alpine Astro describing the Baader 2" Clicklock Diagonal: "SCT Users: The diagonal body's input 2" threading is compatible with the standard Celestron/Meade 2" rear cell threads, enabling you to directly thread it onto your SCT." So is the threading on the diagonal 2" or SCT? When I think of 2" threading, I'm thinking of the 48mm threading compatible with 2" filters, not SCT threading.

 

Since I already have a Baader 2" Clicklock eyepiece adapter, I'd rather purchase a Baader 2" Clicklock Diagonal without the Clicklock eyepiece adapter.  I don't need two of those adapters.

 

Does anyone know if I can purchase just the diagonal body for the Baader 2" Clicklock Diagonal without the 2" Clicklock eyepiece adapter?

 

Mike


Edited by Sarkikos, 23 August 2014 - 08:15 AM.


#20 Eddgie

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Posted 23 August 2014 - 07:46 AM

 

In the OP I was talking about Baader T-2 Maxbright Mirror Diagonal - 2" http://www.optcorp.c...onal-2inch.html.  Unfortunately, this diagonal is sometimes called a 2", other times called a 1.25", which confuses matters even more.

 

 

 

 

Well, the link you sent says the T2 Mirror is a 2" diagonal, but it is not really a 2" diagonal.    It can be configured with a 2" nose, but it is not a 2" diagonal.

 

There are often confusing ads for the Baader stuff.

 

I was just holding a T2 Mirror of the type in your link in my hand with a digital caliper.   The input side (where the nose screws on) measures 34mm.

 

The top side where the eyepeice holder or binoivewer screws on is 33.2mm.

 

This diagonal is clearly not a 2" diagonal, and it can't be mounted to the rear threads without an SCT Adapter.   The 10mm adapter can be used with the locking ring if you want, but the total light path would then not be much less than the Baader Clicklock 2" diagonal (comparing them both with eyepeice holders or without, as you like).

 

The Baader Clicklock 2" diagonal has SCT threads on the front.   You remove the 2" nose and screw the the mirror box directly to the rear port.  It is not M48 threads.

 

All of this is shown in the link I posted above, but I understand your confusion.  The ad you linked to the T2 Mirror is simply incorrect.

Again, I have one of these, and the measurements I gave you were ones I just too prior to writing this response.


Edited by Eddgie, 23 August 2014 - 07:47 AM.


#21 Eddgie

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Posted 23 August 2014 - 08:03 AM

Mike,

Look at the link I sent you above showing how the clicklock diagonal works with the locking ring.

 

It has pictures of all the threads and will answer most of your questions.

 

Again, the T2 Mirror is not a 2" diagonal, and the ad you linked was incorrect.   It can have a 2" nose, but so can the 1.25" prism.  That does not make it a 2" diagonal though.

 

Take some time to look at the link I sent you though, and it shows the front and top threads on the Clicklock.

 

And here is a Specification page on the Clicklock diagonal with some info on interface threading...

 

http://agenaastro.co...r-diagonal.html


Edited by Eddgie, 23 August 2014 - 08:06 AM.


#22 Sarkikos

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Posted 23 August 2014 - 08:13 AM

Unfortunately the Baader Clicklock 2" Diagonal is out of stock at Agena Astro. It is available at HPS and Adorama.

 

Mike



#23 Eddgie

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Posted 23 August 2014 - 08:20 AM

Only including the links for the data they contain.  Don't really care where or even if you buy it.  Just trying to help you with info on the differences between them to help you determine if it is the right solution for you.



#24 dotnet

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Posted 23 August 2014 - 08:24 AM

Maybe the T2 system chart and parts list help? The parts list also shows thread sizes, effective optical lengths etc.

 

http://www.baader-pl...m-grafik-en.pdf

http://www.baader-pl...-tabelle-en.pdf

 

Cheers

Steffen.



#25 RAKing

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Posted 23 August 2014 - 09:12 AM

Unfortunately the Baader Clicklock 2" Diagonal is out of stock at Agena Astro. It is available at HPS and Adorama.

 

Mike

 

Mike,

 

Try Alpine Astro. Bob Luffel shows both the diagonal and the SCT ring in stock.

 

He is a great guy to work with and ships fast.

 

Cheers,

 

Ron








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