GSO 2" 90-deg Mirror Diagonal for SCTs

4.0 GSO 2" SCT diagonal

Quick service. Fit and finish are very good. Brass compression rings are a nice touch. Price point excellent. Threaded collar may be a wee bit out of round.

This review was provided courtesy of AgenaAstro.com

4.0 It is what I needed.

It is what I needed.

This review was provided courtesy of AgenaAstro.com

4.0 Good buy for a non-dielectric diagonal

Easy to Use,Compact,Quality Lenses,Strong Construction

Nice 2" diagonal that attaches directly to the SCT. Works well and the mirror seems very good. I also have a GSO 2" Dielectric model - would give the nod to the Dielectric one for fit/finish/brightness of image. But for the price the regular polished mirror model is very good.

This review was provided courtesy of AgenaAstro.com

5.0 I would buy this product again and again

QUALITY MIRROR,Strong Construction,Easy to Use

None

I find the 2" diagonal a great addition to my C6 sct scope. Many do not recommend 2" acessories for small sct's, but in my experience I find the 2" diagonal very useful. I can use 2" widefield eyepieces which are more comfortable to use. I realize TFOV is still somewhat limited by the sct design, but IMO viewing is easier.

I also find the larger diagonal to be much more stable and strong, much better than the original which contains more plastic.

By using the SCT type diagonal, I am not adding very much distance to the focal plane, so not adding to the focal length of the scope to any great degree.

I would buy this item again in a heartbeat and recommend it. I have not used a dielectric diagonal, but do not see how it can be much better. This one is terrific.

This review was provided courtesy of AgenaAstro.com

4.0 Upgrade to Classic C8

Quality Lenses,Strong Construction,Accurate

Adding this diagonal to a Classic C8 requires a little bit of skill to line up the threads. Apparently, a Classic C8 is not threaded like a later C8 - the threads are smaller. This will work, but know that you will only get a few turns. I needed to use a wrench to make sure it was tight. Not the fault of GSO.

This review was provided courtesy of AgenaAstro.com

5.0 None better at any price!

Accurate,Superb Quality Mirror,Solid - Built Like A Tank,Strong Construction

I'd put this 2" Diagonal up against any from the expensive name brands like TeleVue and Astro Physics any day of the week. It's that good!

Have another one for my 80mm f/6.25 refractor as well.

This review was provided courtesy of AgenaAstro.com

5.0 Best deal in diagonals

Strong Construction

Happy with the quality of GSO products. Threaded body allows additional barrels to be used making the product interchangeable between SCT and refractors.

This review was provided courtesy of AgenaAstro.com

5.0 Go 2", there's no excuses anymore

Accurate,Strong Construction

Heavy

It used to be a dream to go to those great 2" eyepieces. Not anymore. For this price you can get those wide fields your SCT can give you and have money leftover for the eyepiece!

OK, it is a bit on the heavy side and may upset your balance. It might also cause you not to clear zenith depending on your scope. However, machining is excellent; fit and finish is top notch; and a camera can be held very securely. This diagonal also brings the eyepiece up a bit so smaller profile eyepieces may be easier to see through if your head hits the tube.

This was an upgrade from a 1.25" dielectric diagonal, and I can not obviously see the difference between this, the dielectric, or even the original prism! If you're having trouble justifying the quartz or dielectric or carbon fiber, here is your diagonal.

This review was provided courtesy of AgenaAstro.com

5.0 Best upgrade for the buck for your SCT

High quality for a very reasonable price

none at all

I bought this to upgrade my 1.25" diagonal that came with my C8. My first impression taking it out of the box was how well the GSO was machined and how dust free the mirror was. I connected it to my GSO skylight filter. I had to add more weight to the front of the scope to balance it out a bit. The 2" diagonal give plenty of clearance to swing the scope 360 degrees (fork mount).

I could not see much of a difference between my 1.25" and the new diagonal with Jupiter but the Jovian moons were just a bit brighter. The big surprise came with finding M31. The GSO diagonal brought out much more detail in the spiral arms, viewing expanded them an arc second or so compared to my 1.25". I can't wait to try it out on some DSOs this winter. I rate this excellent as I can not see some $300 diagonal being any better.

4.0 Very well made, Nice upgrade

Accurate,Strong Construction,Quality Lenses

Purchased for C8 to replace a stock 1 1/4. The stock diagonal had visible distortion and smearing when attempting collimation - (sigh) disappointing but pretty much junk. If you are wondering why during collimation you get long rainbow looking smears (that disappear with no diagonal), get this product. This diagonal provides a view during collimation that looks equal to the lens installed with no diagonal. It is also very solid and enormous when compared to the 1 1/4 size. This product provides plenty of support for attachment of small SLR (Canon 400). A great price to benefit ratio on a budget, coming in at 35% less than a 99% dielectric model.

This review was provided courtesy of AgenaAstro.com

4.0 A 2" Diagonal that fits every budget

Strong Construction,Quality Lenses,Big Value

I wanted to get my feet wet in 2" eyepieces, but didn't want to spend a lot of money without knowing if I would really like the 2" formats. This is a great value for those of you looking to sample the benefits of 2" wide field eyepieces. Its a step up from the standard, plastic 1.25 diagonals that come with most scopes. Optically it performs as good as the other diagonals, with the benefit of wider fields of view, as well as adding some "attitude" to your astro rig, it just looks darn good on a SCT. A wonderful value in my opinion.

This review was provided courtesy of AgenaAstro.com

4.0 Solidly built, good images

Solidly built; Better than stock diagonal; Good value

None noticeable

I bought this to replace the stock 1.25" diagonal that came with my second hand Nexstar 8 GPS, and I'm happy with my purchase.

It seems to be solidly built, threads on very cleanly and I think the images are bit brighter than the stock diagonal.

I also like the fact that Agena Astroproducts sells the chrome refractor style end tube separately, and I bought that and a 2" SCT adapter at the same time so I could use it both ways (mainly for filters and threading the barlow from 20mm 80 degree Agena UWA eyepiece in before the diagonal).

Good value, especially for the price, and I love the versatility of using it with filters and the barlow element.