Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> Eyepieces

Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | (show all)
Starman1
Vendor (EyepiecesEtc.com)
*****

Reged: 06/24/03

Loc: Los Angeles
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5642745 - 01/25/13 02:54 PM

Quote:

Don,

Quote:

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.

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. 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.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5642751 - 01/25/13 02:57 PM

Yes, indeed!

Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
Starman1
Vendor (EyepiecesEtc.com)
*****

Reged: 06/24/03

Loc: Los Angeles
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5642764 - 01/25/13 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.


Post Extras: Print Post   Remind Me!   Notify Moderator  
bob midiri
Carpal Tunnel
*****

Reged: 06/17/04

Loc: pa 19320
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5642876 - 01/25/13 04:04 PM

Quote:



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


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5642906 - 01/25/13 04:16 PM

Don,

Quote:

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


Post Extras: Print Post   Remind Me!   Notify Moderator  
Starman1
Vendor (EyepiecesEtc.com)
*****

Reged: 06/24/03

Loc: Los Angeles
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: bob midiri]
      #5643027 - 01/25/13 05:35 PM

Quote:

Quote:



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



It's a common problem with ALL Chinese mirror diagonals in 2".
I don't think they're blems. I think they're surplus from what came standard on the larger SCT scopes.


Post Extras: Print Post   Remind Me!   Notify Moderator  
dscarpa
Post Laureate
*****

Reged: 03/15/08

Loc: San Diego Ca.
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5643361 - 01/25/13 09:06 PM

My WO and Meade diagonals of this type seem spot on collimation wise. I've used them a lot with very good-excellent seeing and nothings amiss. I like them better than the OPT 2" diagonal that has sharp edges anda funky set screw in a slot 1.25" adapter. The OPT's optiocs are the equal of the others. David

Post Extras: Print Post   Remind Me!   Notify Moderator  
Toddeo
newbie


Reged: 01/19/12

Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5643463 - 01/25/13 10:12 PM

Thanks for the info on the Meade deal, I just placed the order- cant beat a deal like that!!!!

Post Extras: Print Post   Remind Me!   Notify Moderator  
bob midiri
Carpal Tunnel
*****

Reged: 06/17/04

Loc: pa 19320
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5643967 - 01/26/13 08:43 AM

Quote:

Quote:

Quote:







It's a common problem with ALL Chinese mirror diagonals in 2".
I don't think they're blems. I think they're surplus from what came standard on the larger SCT scopes.




Thanks Don


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: bob midiri]
      #5644123 - 01/26/13 10:33 AM

"Order Status: Shipping Soon
Your order is being prepared for shipment and cannot be canceled or changed. Your order should ship within the next business day."



Post Extras: Print Post   Remind Me!   Notify Moderator  
faackanders2
Carpal Tunnel


Reged: 03/28/11

Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5644140 - 01/26/13 10:43 AM

Yes, this is a 24mm 82AFOV UWA eyepiece. The outer housing screws up and exposes some grease and it does freeze or get stiff in cold temps, so I just keep it up in cold temps when I am observing with it. Views are good in UWA, and the raised outer housing does block stray light.

ES version does not have the outer housing, which many consider a benefit (smaller, no grease).

Price looks very good for the combo sale. Enjoy!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5644141 - 01/26/13 10:43 AM

I always collimate refractors straight-through, without a diagonal in the focuser. Before I observe, I check the collimation with the diagonal. If I the collimation is off, I fiddle with the setscrews or wedge it if necessary to improve the collimation. If I can adjust the diagonal itself, that's even better. I suppose that's how I should proceed with collimating my SCT?

All of this would be easier if I didn't have to wait until I'm out in the dark to collimate. I can collimate refractors and Newts in broad daylight or in my house if I want to. Actually it's EASIER then. Isn't there some way to collimate SCTs accurately without a star test?

Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: faackanders2]
      #5644150 - 01/26/13 10:47 AM

faackanders2,

Quote:

Yes, this is a 24mm 82AFOV UWA eyepiece. The outer housing screws up and exposes some grease and it does freeze or get stiff in cold temps, so I just keep it up in cold temps when I am observing with it. Views are good in UWA, and the raised outer housing does block stray light.




I already have three Meade 5k UWA/SWA eyepieces. I never had a problem with the grease or with cold weather, but then I don't go out if it gets much below freezing. So far I've deshrouded all these eyepieces and put after-market eyecups and caps on them. I'll do that for the new UWA 24, too.

Quote:

Price looks very good for the combo sale. Enjoy!




Yes indeed!


Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
faackanders2
Carpal Tunnel


Reged: 03/28/11

Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: mfromb]
      #5644162 - 01/26/13 10:54 AM

Quote:

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.




24mm 68AFOV vs. 24mm 82AFOV. No brainer go for 24mm 82AFOV w/ free diagonal!


Post Extras: Print Post   Remind Me!   Notify Moderator  
faackanders2
Carpal Tunnel


Reged: 03/28/11

Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: REC]
      #5644170 - 01/26/13 10:59 AM

Quote:

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 $$$




bREAK EVEN AT BEST. Others in the know would prefer to buy new vs. buying used. But it is an excellent price!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Starman1
Vendor (EyepiecesEtc.com)
*****

Reged: 06/24/03

Loc: Los Angeles
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5644269 - 01/26/13 11:52 AM

Quote:

I always collimate refractors straight-through, without a diagonal in the focuser. Before I observe, I check the collimation with the diagonal. If I the collimation is off, I fiddle with the setscrews or wedge it if necessary to improve the collimation. If I can adjust the diagonal itself, that's even better. I suppose that's how I should proceed with collimating my SCT?

All of this would be easier if I didn't have to wait until I'm out in the dark to collimate. I can collimate refractors and Newts in broad daylight or in my house if I want to. Actually it's EASIER then. Isn't there some way to collimate SCTs accurately without a star test?

Mike



Mike:
Get a Christmas tree bulb ornament.
Hang it in a tree 200' to the north of you.
Focus the telescope on the reflection of the Sun in the bulb.
The image will be an Airy disc with diffraction rings.
Take your time to collimate. Seeing won't interfere, and you can use very high power eyepieces and get it accurate.
And you didn't waste one minute of nighttime observing.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Starman1]
      #5644357 - 01/26/13 12:54 PM

Easier said than done. I live in a condo. I don't have a back yard. Might seem a little unusual to see a middle-aged man shimmy up a tree in the common area to hang up a Christmas bulb.

Hasn't anyone developed a simple gizmo for collimating an SCT in the privacy of one's own home? We are not beasts. Are we not men?


Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
Starman81
Carpal Tunnel
*****

Reged: 03/06/08

Loc: Metro Detroit, MI, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 new [Re: Sarkikos]
      #5644513 - 01/26/13 02:35 PM

Wow, is that EP really 35 ounces!?!?

Post Extras: Print Post   Remind Me!   Notify Moderator  
Starman81
Carpal Tunnel
*****

Reged: 03/06/08

Loc: Metro Detroit, MI, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 [Re: Starman81]
      #5644537 - 01/26/13 02:45 PM Attachment (11 downloads)

I don't think that is a misprint after all--I found this thread in the archives and user 'acc' originally posted the picture below.

It makes the 35 Pan look downright anorexic!!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarkikos
Postmaster
*****

Reged: 12/18/07

Loc: Scotophobe Maryland, USA
Re: Meade UWA 24mm & 2" Dialectric Diagonal: $159 [Re: Starman81]
      #5644574 - 01/26/13 03:06 PM

35 ounces. That's virtually the same weight as my ES 82 30mm. At least you can put the Meade UWA 24 on a diet by getting rid of the bulky shroud.

Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | (show all)


Extra information
18 registered and 26 anonymous users are browsing this forum.

Moderator:  ausastronomer, droid, Scott in NC 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 10111

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics