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View the Latest Diagonals & Prism Reviews

Item
Submitted By
William Optics 2
William Optics 2" 99% Dielectric Dura Bright Carbon Fiber Mirror Diagonal for Refractors
4.0
Nice diagonal
First off, just so you're aware, this thing is not small. I put it on a Celestron 6SE with no problems at all. Removed the visual back, screwed this right on. Build quality feels nice and solid. The large thumb screws are nice and work well. The...
GSO 1.25
GSO 1.25" 90-deg Erect Image Amici Prism Diagonal # PD90
5.0
A TRUE BARGAIN
This 2" diagonal is an excellent quality device at half the price you'd pay for a "brand name".
Celestron 1.25
Celestron 1.25" 45-deg Erect Image Diagonal # 94112-A
2.0
small internal prism causes vignetting, reduces FOV
This 45* correct image diagonal prism actually has a clean, sharp image. The problem is that becuase of the small prism (20mm trying to feed 32mm eyepieces), the outer 10% of the FOV is vignetted... that is darker than the other 90%. For that reason...
GSO 1.25
GSO 1.25" 90-deg Mirror Star Diagonal for Refractors # GSST
5.0
Great buy
Exactly what I need for my late 50’s Tasco !
William Optics 2
William Optics 2" Push-In Nosepiece for William Optics Diagonals
5.0
Nose Piece
An excellently crafted piece. Most of all however I appreciated the time an effort that your customer service person spent in making sure that it was a compatable piece for my equipment.
William Optics 1.25
William Optics 1.25" 99% Dielectric Dura Bright Carbon Fiber Star Mirror Diagonal
5.0
William Optics 1.25" 99% Dielectric Dura Bright Carbon Fiber Star
A very beautiful piece of equipment! Can't wait until the weather once cooperates so I can finally use it. Solid and well built and I'm sure it'll perform beyond my expectations.
GSO 2
GSO 2" 90-deg 99% Quartz Dielectric Mirror Diagonal for Refractors
5.0
Better than I thought it
Better than I thought it would be, very pleased with it, would recommend to any one.
GSO 1.25
GSO 1.25" 90-deg Mirror Star Diagonal for Refractors # GSST
5.0
Great With My ST80 Clone
I bought this to replace the correct image prism diagonal that came with my ST80 clone, which is a Meade Adventure Scope. The prism was ok for lower magnification terrestrial viewing, but not for astronomy. This GSO mirror diagonal is lightweight and...
William Optics 2
William Optics 2" 99% Dielectric Dura Bright Carbon Fiber Mirror Diagonal for Refractors
5.0
Perfect
Quality and finish for this accessory.I rediscover the deep sky.Use on CPC 1100
GSO 2
GSO 2" 90-deg 99% Dielectric Mirror Diagonal for Refractors
5.0
Another great eyepiece from Agena!
Highly recommend!!!! 5-stars
Celestron 1.25
Celestron 1.25" 45-deg Erect Image Diagonal # 94112-A
4.0
Works as described for the right application
This does exactly as described. I did find, however, that it was les than ideal for astronomical use. I wanted a right view for public night and it worked just fine. Perhaps out of long habit, I felt the conventional 90 degree was more comfortable. F...
GSO 1.25
GSO 1.25" 90-deg 99% Dielectric Mirror Diagonal with Compression Ring
4.0
Nice GSO Diagonal
Needed another good 1 1/4" diagonal. I purchased a GSO 1 1/4" diagonal with a compression ring. This is a nice good quality diagonal and I use it all of the time.
GSO 2
GSO 2" 90-deg 99% Quartz Dielectric Mirror Diagonal for Refractors
5.0
GSO 2" diagonal
Works as advertised. Excellent views. Holds all my 2" eyepieces securely. Nice product at a very reasonable price.
GSO 1.25
GSO 1.25" 90-deg 99% Dielectric Mirror Diagonal with Compression Ring
5.0
GSO 1.25" 90-deg 99% Dielectric
very good
GSO 2
GSO 2" 90-deg 99% Dielectric Mirror Diagonal for Refractors
5.0
GREAT 2" MIRROR DIAGONAL YIELDING OUTSTANDING LIGHT THROUGHPUT
I HAVE OWNED MANY 'ENHANCED' MIRROR DIAGONALS FROM 1 1/4" TO 2". I'VE OWNED MOST ALL FROM EVERY MANUFACTURE YOU CAN NAME, AND SOME YOU CAN'T. THIS IS A STELLAR PERFORMER AT A GREAT PRICE! I USE THIS IN A GSO 6" CASS...
GSO 2
GSO 2" 90-deg 99% Dielectric Mirror Diagonal for SCTs
5.0
Heavy, but very good
I got this diagonal to be able to sin: to use my C6 with my 2" 20mm 82° Meade UWA eyepiece AND my Meade F6.3 reducer. It worked and I enjoyed the view of the Pleiades (it's so much better than with the equivalent 32mm Plössl). However, be...
GSO 2
GSO 2" 90-deg 99% Quartz Dielectric Mirror Diagonal for SCTs
5.0
Quality Quality Quality
Makes the stock diagonal feel and look like a toy...
GSO 1.25
GSO 1.25" 90-deg 99% Dielectric Mirror Diagonal with Compression Ring
5.0
Bright
Needed a new better diag than what came with the scope. Tried the GSO and it is every bit as bright as my Televues.