William Optics 1.25" Carbon Fibre Dielectric Diagonal

[Midpoint]

Evening,

Does anyone have any opinions on this diagonal? I'm still using the stock diagonal that came with my Nexstar 6SE so I was wondering if the claims that it "offers a noticeable improvement" were generally considered noticeable or not?

Any feedback would be greatly appreciated, thanks,

[Gadget]

I had one of these on my 8SE they are a great diagonal for the money deffo a big improvement in finish and build quality over a stock one and usually it is the first upgrade most make to their kit although the visual improvement wont blow your socks off it will be there but it does all add up by the time you add better quality eyepieces etc

Kevin

[brantuk]

Crickey - they've come down a lot in price - mine was a lot more 18mths ago. Very nice diagonals and more substantial for mounting 2" eye pieces. Great with binoviewers too, especially in a mak or sct

[CGolder]

I think this is the 1.25" version kim no wonder its gone down in price

[Midpoint]

Yeah, it's only the 1.25" version, sorry

@Gadget: It doesn't sound like you think it makes a huge difference visually. In your opinion, would the money be better spent on a nice eyepiece instead?

[Mike_F]

Yeah, it's only the 1.25" version, sorry

@Gadget: It doesn't sound like you think it makes a huge difference visually. In your opinion, would the money be better spent on a nice eyepiece instead?

The general consensus does seem to be that diagonals only make marginal improvements to image brightness / quality. However, that's missing a point when comparing the stock Celestron diagonal to the one you've selected there. One of the main benefits of upgrading is gaining compression ring clamping - rather than those damned grub/thumb screw things.

Personally, I would never put a "nice" eyepiece in a fitting that secures it with grub screws. Far too easy to mar / damage the barrel.

So, my answer would be: "get both"

Mike.

[michael.h.f.wilkinson]

I got the 2" and that did make a big difference, probably because the optical surface is flatter over the section "seen" by 1.25" EPs. The build quality is excellent. The coatings of these dielectric diagonals also appear to last longer than the bog-standard ones.

[Midpoint]

Ah, I didn't even factor in the compression ring. I never realised that it would be considered that important.

Thanks, now I've got even more for my little brain to think about!

[jgs001]

I've just recently got one of these myself second hand to replace a stock diagonal. Whilst I've not had an opportunity to use it as yet, I have to say, it feels very, very solid and built to last. Far more so than the stock diagonal, which I was always a little wary about putting the Hyperions into.

[red dwalf]

i boughrt one of these from Kelling last autumn, £40 second hand also to use on my 6" sct nexstar scope, build quality is brill, compression fitting holds eyepiece soild and does not mark eyepieces, i comparied it to the stock diagonal just by looking through each and the brightness and detail seen through the william optics is miles better, the stock diagonal looks dull and dim compaired to the williams version, well worth the upgrade in my opinion and these sell very quickly second hand.

[E621Keith]

I have got the WO 1.25" as well. It's nicely built and well blackened. It's a significant step up from the standard plastic 1.25".

The only thing I didn't like was it's smooth polished nose piece. Compression rings can't seems to apply enough grip on the barrel to stop heavy accessories (such as binoviewers) from rotating.

[alan potts]

I have used a friends WO, as Keith says very nice all round, this was the 2 inch version.

Alan

[M4lcs67]

I'm in the market for the "2 version to go with my C9.25 after Martin @ FLO recommended it. I had a situation a few weeks ago when the grub screw on my stock diagonal worked loose and it fell to the ground with my brand new Hyperion eyepiece still attached. Luckily it fell onto soft grass, so no damage was done. However if gave me a real shock and I thought that there must be a better way than a lousy grub screw to attach everything to the scope. After much searching and a recommendation from one of my buddies I found the Baader Clicklock system, that when locked into position grips the barrel of the diagonal all the way around and not at just one small area and also doesn't do any damage to the barrel of the diagonal as the one with just the grub screw does, where it just gouges into the metal and leaves scratches and marks.

And also With the 2" diagonal you have the opportunity to use 1.25 eyepieces with the supplied adapter as well as 2" ones and that is where I want to go. Wider views and I have the Baader Hyperion Aspheric 36mm on my radar and put the 2" end into it.

In any case there is plenty of time to get it all together, so I am in no rush.

[glowjet]

If it can be avoided I would never now use accessories with just a locking screw, the damage caused to the barrels of the various fitments can be quite horrendous, plus the fact that they have a nasty habit of coming loose when you least expect it. Brass marring rings, which are now fitted to most quality accessories should be your first choice and even better some of the self centering clicklock devices such as the Baader unit take things a step further, but come at a price, but most useful when used in in AP as it helps keeps the device on the centre of the optical axis. If you can afford the price of a 2" diagonal with a 1.25" adapter then do so, makes such as the Williams are excellent quality, when used with Hyperions they have a built in stop to prevent the 1.25" nose piece from touching the mirror when used in the 2" mode

John.

[cs1cjc]

I use the 1.25" and it is very nice and solid. My only reservation is that the barrel is tight internally at less than 25mm (compared with a 27mm field stop on the widest 1.25" eyepieces.

[John]

I use the 1.25" and it is very nice and solid. My only reservation is that the barrel is tight internally at less than 25mm (compared with a 27mm field stop on the widest 1.25" eyepieces.

Yes, I noticed that. Slightly annoying if you want to use such eyepieces as you get a little vignetting. The internal ring that holds the barrel onto the body of the diagonal is rather thicker than it needs to be.

Otherwise a nice diagonal.

[M4lcs67]

If it can be avoided I would never now use accessories with just a locking screw, the damage caused to the barrels of the various fitments can be quite horrendous, plus the fact that they have a nasty habit of coming loose when you least expect it. Brass marring rings, which are now fitted to most quality accessories should be your first choice and even better some of the self centering clicklock devices such as the Baader unit take things a step further, but come at a price, but most useful when used in in AP as it helps keeps the device on the centre of the optical axis. If you can afford the price of a 2" diagonal with a 1.25" adapter then do so, makes such as the Williams are excellent quality, when used with Hyperions they have a built in stop to prevent the 1.25" nose piece from touching the mirror when used in the 2" mode

John.

Hey John

So by using this set-up there would be no chance of the nosepiece of the eyepiece touching the mirror in either 1.25" or 2" mode?

[glowjet]

That is correct, with the williams 2" diagonal, the internal stop is set so that you may use Hyperions in "2 mode, so that the 1.25" nose piece is kept from causing damage to the mirror, as you will appreciate this gives a much firmer grip when the lenses are used in the 2" mode, especially with a camera screwed onto the eyepiece end, as in afocal photography. For 1.25" you would of course use the supplied 1.25" adapter. As far as I am aware the Williams body is identical to the Astro-Tech models which also has a similar stop and are quality made, with multi coated mirrors etc, but for some reason are now difficult to obtain in the UK but often come up on the s/h market. I had a 2" Astro-Tech for some time and compared with the same Williams unit, they were of similar manufacture. On one of those strange serendipity moments, however, I managed to part with my 2" Astro-Tech and obtain a Williams 2" Quartz model, which is about as good as it gets

John.

[M4lcs67]

Good call.

Thanks for that info. I think I am heading ever closer to walloping the credit card again for a few more bits. Good job it has been cloudy for an absolute age.

[Dunkster]

All the more time to window shop, Malc

[M4lcs67]

Absolutely right, Dunk.

[M4lcs67]

Trying to explain why I need a new piece of kit to the missus is nigh on impossible. But why do you need this? Doesn't it come supplied with that? Yes dear, but it is a rubbish basic item that the telescope manufacturers supply you with as a bare minimum. Barely fit for purpose, so as soon as you can, of course you want to upgrade various bits and bobs. I guess we are lucky in as much as it is possible to improve things at a pace that your wallet can cope with.

[Stargazer_00]

Absolutely and the less your wife is interested the quicker those upgrade can come

[Grotemobile]

The trouble is ,when she wants that new bag,

she has seen in the shop ,& you have spent

the money on a new piece for the scope.Ouch.

Lots of groveling.

Steve.