View Full Version here: : Which 2" diagonal?

20-09-2016, 09:05 PM
Hi All

The tax man supplied me with a little money and I intend to buy a dielectic diagonal to replace the stock Meade one on the LX90.

I am thinking of a Williams Optics one, but, have no idea which of these two I should pick D-DIG2D-C-DB DuraBright 2" or D-DIG2D-C 2".

I don't know what the difference really is. Both $199 from Andrews Communications.

Comments about these two would appreciated, as would suggestions for similar quality units upto the same sort of price.

Thank you


20-09-2016, 10:12 PM
I had both the Williams Optics Dielectric Diagonal and a GSO Dielectric Diagonal.

I found the Takahashi 1/10 2inch diagonal to be a lot better than either.

Also the Baader Diagonals are good too.

All depends on your budget .......but one thing to think about is that if you are planning to be doing astronomy for a while? and if you plan a future scope upgrade getting a very good diagonal and a few very good eyepieces will last you through many different scopes as they stay with you when you sell your OTA

22-09-2016, 08:31 AM
Thanks for the reply

Definitely can't justify the Takahashi, but, even the Baaders are just that bit to pricey. I would like a Baader click-lock.

I very much agree about trying to buy the extras that will be kept long term.


22-09-2016, 09:15 AM
I suspect the D-DIG2D-C-DB DuraBright is simply the latest version of the D-DIG2D-C, with a thicker mirror and "improved" coatings. The D-DIG2D-C is probably old stock.
I have the GSO 2" dielectric, which I use on my Celstron CPC 800: it was a big improvement on the stock diagonal- I saw textbook star images for the first time, instead of funny blurs with the original! ;)
I have also tried one with an LX90, with similar improvement in images.

22-09-2016, 11:06 AM
Hi Dean

Thanks for the info.

I am expecting at least a fair improvement, as I did try looking at the same star, same eyepiece - with and without the stock diagonal, that made quite a difference.


22-09-2016, 11:29 AM
Phillip, you will also need an adapter to convert the visual back to 2".
Some diagonals can be bought with them. Andrews charge $59 for an SCT adapter as it is not included with the diagonal.

22-09-2016, 12:14 PM
Good point Matt! Andrews also sell the GSO diagonals for SCT's for the same price as their normal GSO diagonal.

22-09-2016, 12:17 PM
if it were me id get the bintel / andrews GSO 2" or if you want the quartz version from the same maker..just a bit heavier than the WO but essentially the same