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Meade UWA 24mm & 2" Dialectric Diagonal: $159

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#1 Sarkikos

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Posted 24 January 2013 - 09:01 PM

Today I received an email from Meade with some special offers. One offer is for a Meade UWA 24mm and a 2” 99% reflectivity dielectric mirror diagonal with 1.25” adapter for $159.

I pulled the trigger on this offer. I'd like the 2" diagonal for my new C6 SCT. According to Meade, it comes with "an adapter that allows the diagonal to be used with a standard SC thread screw-on attachment." I've seen this same diagonal advertised alone for around $159.

For the special offer, I'm getting the eyepiece as an extra "Wait! Wait! There's more!" :grin: I've read that the Meade UWA 24 has pretty much the same optics as the ES 82 24, but is not nitrogen/argon purged. I don't have this ES eyepiece, but it's one that I've been thinking about picking up. The ES 82 24 is on sale now for $199. I've seen the Meade UWA 24 advertised recently for $224. I may be confusing these Meade UWA with the SWA - now how is that possible? - but I believe both the UWA and SWA were on sale a couple years ago for much less.

Here is a link to this offer from Meade:

99% Reflectivity Diagonal and 24mm Ultra-Wide Angle Eyepiece Kit

I have no affiliation with Meade or any other vendor ... except as a customer!

:grin:
Mike

#2 bob midiri

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Posted 24 January 2013 - 11:08 PM

I got that email also. deal is pretty hard to beat

#3 Sarkikos

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Posted 24 January 2013 - 11:10 PM

I could not resist it! :grin:

#4 Sarkikos

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Posted 24 January 2013 - 11:16 PM

When I receive the Meade UWA 24, I will promptly put it on a diet. These eyepieces are a bit bulky.

How To Put a Meade 5000 on a Diet!

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#5 bob midiri

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Posted 24 January 2013 - 11:18 PM

I could not resist it! :grin:

Me either, its a sickness :roflmao:

#6 stevew

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Posted 24 January 2013 - 11:38 PM

I'd like the 2" diagonal for my new C6 SCT.
:grin:
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Does the C6 have a 2 inch baffle tube?

#7 mfromb

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Posted 24 January 2013 - 11:41 PM

Wow.. that seems like a crazy good deal. I have the ES68 24mm on backorder. I think I am somewhere around 100,459th in line. IF this Meade is largely the same as the ES82 24mm, then dang. The $159 for the EP itself is a solid price. I think that EP sells for over $200, normally.

Things that make you go 'hmmm...' at 11:30 p.m. Should I cancel the ES68 and jump on this. I have no use for the diagonal, but maybe I could mount it for display on the mantle?!?

I should stop looking at that offer now, before my credit card numbers mysteriously tap themselves onto the keyboard.

#8 bob midiri

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Posted 24 January 2013 - 11:47 PM

If it were I, I would cancel the ES order. You will be surprised that some day you can use another 2" diagonal ....or sell it. bob

#9 Sarkikos

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Posted 25 January 2013 - 12:43 AM

I'd like the 2" diagonal for my new C6 SCT.
:grin:
Mike

Does the C6 have a 2 inch baffle tube?


I'm not sure. The C6 is supposed to arrive tomorrow. But in any case, a 2" adapter and diagonal make for a more secure connection. I can always use it on my Mak if I don't like it on the C6.

Mike

#10 Scanning4Comets

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Posted 25 January 2013 - 01:16 AM

Here's mine that I used to own. Exact same performance as the ES 24mm 82 degree EP, and much better de-cloaked.

Attached Files



#11 csrlice12

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Posted 25 January 2013 - 09:31 AM

I have the old ES82 24mm, before they were waterproofed; and it's a beast at 2.2 lbs...And that eyepiece will not leave my grimey paws. Of ALL my eyepieces, this is my favorite (even over the Naglers). It sees more scope time then all my others put together...It was also my "first" premium eyepiece.

#12 REC

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Posted 25 January 2013 - 10:29 AM

That's a hell of a deal! If I didn't already have that diagonal and a 24mm SWA and a 28mm SWA I'd be all over it...you could buy it and sell them off separately and make $$$

#13 Sarkikos

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Posted 25 January 2013 - 10:51 AM

:thinking: :money:

#14 mitaccio

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Posted 25 January 2013 - 11:13 AM

I had to get it. I was ready to spend over $360 for a WO diagonal and the ES 82 24mm. Now I have funds to spend on more stuff! This is a great start to the day!

#15 dscarpa

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Posted 25 January 2013 - 11:25 AM

I agree it's good to have a spare diagonal. A month ago I dinged my OPT dialectric diagonal. I put a eyepiece in a 1.25" barlow into it thinking the adapter was in it when it wasn't. I replaced it with a WO dialectric diagonal for $129. I've got the Meade diagonal too and except for carbon fiber sides on the WO vs metal on the Meade they are the same and highly recommended. I've got 5.5 and 18 UWAs both of which are very good eyepieces. Thanks for the heads up! I'm going to get the diagonal-24 UWA. David

#16 SeptemberEquinox

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Posted 25 January 2013 - 12:01 PM

I just got Celestron Omni Xlt 150 refractor that came with 1.25" dielectric diagonal. I thought about buying Meade 2", but I wanted to save some money and buy an eyepiece. But wow what a deal. Thank you for sharing. Are there gonna be slight improvement from 1.25 diagonal to 2"?

#17 Starman1

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Posted 25 January 2013 - 12:51 PM

1) The C6 has about a 25mm opening in the back of the baffle. It's best with 1.25" eyepieces, but as long as you keep the field stop diameter smaller than, say, 30mm, vignetting shouldn't be too severe.

2) Meade used to source these eyepieces from Jing Hua (the source for Explore Scientific). Now they come from another company in China. That Meade is making this deal possibly means these were left-over eyepieces from before the company switch, in which case they might be from Jing Hua.

3) The primary advantage to the switch to 2", even if the scope isn't really designed for 2" eyepieces will be that only the center of the star diagonal's mirror will be being used. And, as many optical reports have shown--especially on dielectric-coated mirrors--there is often a roll-off of optical quality toward the edge of the mirrors. Using just the center of the mirror would improve the optical figure of the system over using a 1.25" mirror and utilizing most of the mirror.

4) These star diagonals may have a misaligned mirror. To test that, if you don't know how to do it off the scope, make sure your SCT is well collimated with a 10mm eyepiece straight through (no diagonal in place).
In the northern hemisphere, Polaris makes a good collimation star. Then, place the star diagonal on the scope and check collimation again. If you see a lack of collimation, try loosening the setscrew on the diagonal and tipping it slightly. If this improves the star image, sometimes a thin aluminum shim between the star diagonal body and the tube into which it inserts will do the trick. In this way, the scope can be as well-collimated with and without the star diagonal. Remember to always bring the test star to the center of the visible field before testing collimation.

#18 belgrade

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Posted 25 January 2013 - 12:59 PM

All of the above are great comments, especially (4) - advices like this are what makes stopping by these forums worthy our time!

#19 Sarkikos

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Posted 25 January 2013 - 02:30 PM

Don,

1) The C6 has about a 25mm opening in the back of the baffle. It's best with 1.25" eyepieces, but as long as you keep the field stop diameter smaller than, say, 30mm, vignetting shouldn't be too severe.


I had read on CN that the baffle is 28mm. But I measured the opening of my new C6 myself before I read your post, and it is about 25mm, or 1 inch. A good 1.25" eyepiece for low power would be my Ultrascopic 35mm, which would give me about 43x, 1.2 degrees TFOV, and 3.5mm exit pupil. It has a 29mm field stop, right below the 30mm limit that you suggested. :grin:

I don't plan on viewing everything - the big and the small - with my C6. I never really believed that SCTs are Jack-of-all-trade telescopes. I have other scopes and binos that I use for wide field. I wanted the C6 for views of the Moon, planets, the brighter DSO and double stars. Not every scope I own needs to give me a wide view of the Pleiades. :shrug: But this one should show the Double Cluster well enough.

The C6 appears light enough that I can take it out for grab-n-go beside my house, or even backpack it for a 20 minute walk to a nearby site away from the neighborhood glare.

Mike

#20 Sarkikos

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Posted 25 January 2013 - 02:38 PM

Don,

3) The primary advantage to the switch to 2", even if the scope isn't really designed for 2" eyepieces will be that only the center of the star diagonal's mirror will be being used. And, as many optical reports have shown--especially on dielectric-coated mirrors--there is often a roll-off of optical quality toward the edge of the mirrors. Using just the center of the mirror would improve the optical figure of the system over using a 1.25" mirror and utilizing most of the mirror.


Thanks. I had heard the same thing years ago, but had forgotten about this advantage to using 2" diagonals. I was thinking more about having a more secure and stable connection by going to 2".

Mike

#21 Starman1

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Posted 25 January 2013 - 02:54 PM

Don,

1) The C6 has about a 25mm opening in the back of the baffle. It's best with 1.25" eyepieces, but as long as you keep the field stop diameter smaller than, say, 30mm, vignetting shouldn't be too severe.


I had read on CN that the baffle is 28mm. But I measured the opening of my new C6 myself before I read your post, and it is about 25mm, or 1 inch. A good 1.25" eyepiece for low power would be my Ultrascopic 35mm, which would give me about 43x, 1.2 degrees TFOV, and 3.5mm exit pupil. It has a 29mm field stop, right below the 30mm limit that you suggested. :grin:

I don't plan on viewing everything - the big and the small - with my C6. I never really believed that SCTs are Jack-of-all-trade telescopes. I have other scopes and binos that I use for wide field. I wanted the C6 for views of the Moon, planets, the brighter DSO and double stars. Not every scope I own needs to give me a wide view of the Pleiades. :shrug: But this one should show the Double Cluster well enough.

The C6 appears light enough that I can take it out for grab-n-go beside my house, or even backpack it for a 20 minute walk to a nearby site away from the neighborhood glare.

Mike

That eyepiece yields 1.09 degrees. It's no accident the 5, the 6 and the 8 all have about a 1 degree low power view. This was considered the "standard" low power view for backyard telescopes a generation ago. We have proliferated our approaches so greatly since then that you can now buy amateur, backyard scopes with low power fields of view as large as 5 degrees or as small as 0.5 degrees maximum field. We live in amazing times, where amateur astronomy is concerned.

#22 Sarkikos

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Posted 25 January 2013 - 02:57 PM

Yes, indeed!

Mike

#23 Starman1

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Posted 25 January 2013 - 03:04 PM

I forgot to mention that using a 2" star diagonal on the C6 does lengthen the focal length and narrow the field of view some.
I estimate the adapter and star diagonal have about a 5" light path from the back of the scope to the focal plane at the end of the diagonal (it could be 6"). That length makes the focal length of the scope to 76 to 80", or really f/12.7 to f/13.3
That is one of the negatives of using a 2" star diagonal on the back of the scope.

#24 bob midiri

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Posted 25 January 2013 - 04:04 PM


4) These star diagonals may have a misaligned mirror. To test that, if you don't know how to do it off the scope, make sure your SCT is well collimated with a 10mm eyepiece straight through (no diagonal in place).
In the northern hemisphere, Polaris makes a good collimation star. Then, place the star diagonal on the scope and check collimation again. If you see a lack of collimation, try loosening the setscrew on the diagonal and tipping it slightly. If this improves the star image, sometimes a thin aluminum shim between the star diagonal body and the tube into which it inserts will do the trick. In this way, the scope can be as well-collimated with and without the star diagonal. Remember to always bring the test star to the center of the visible field before testing collimation.

Don thanks for this tip, but I'm curious, is this a common problem with this particular diagonal, or do you think these are "blems or seconds"? Thanks Bob

#25 Sarkikos

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Posted 25 January 2013 - 04:16 PM

Don,

I forgot to mention that using a 2" star diagonal on the C6 does lengthen the focal length and narrow the field of view some.
I estimate the adapter and star diagonal have about a 5" light path from the back of the scope to the focal plane at the end of the diagonal (it could be 6"). That length makes the focal length of the scope to 76 to 80", or really f/12.7 to f/13.3
That is one of the negatives of using a 2" star diagonal on the back of the scope.


On the other hand, if you're using the C6 mainly to look at the Moon, planets and double stars, increasing the f number could be advantageous. You could get to a higher magnification with an eyepiece that has a little longer focal length.

Mike






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