Bizarre-looking new eyepieces from Skywatcher

[emadmoussa]

FLO, how much does the 3.5mm weigh? Thanks!

[emadmoussa]

OK, I took the plunge and got the 3.5mm -- if weather allows next week I'll put it to the test ...of course, my review won't be near John's one - so don't count much on my objectivity.

Assuming FLO don't deliver over the weekend ?

[mdstuart]

I have never read so much excitement!

looking forward to your review John.....check the transparency for viewing faint galaxies!

Mark

what I need is an eyepiece that has the ability to correct astigmatism as well as coma!

[John]

OK, I took the plunge and got the 3.5mm -- if weather allows next week I'll put it to the test ...of course, my review won't be near John's one - so don't count much on my objectivity.

Assuming FLO don't deliver over the weekend ?

I may not look at the 3.5mm so your views will be very interesting

[russ.will]

FLO, how much does the 3.5mm weigh? Thanks!

I'd imagine the 1.25" examples all weigh a similar amount.

I could be off the mark here, but I imagine the difference in length is occupied by air as the different focal lengths are achieved by moving the leading Smythe doublet lens group (basically a negative doublet barlow) away from the other six elements to increase magnification, thereby shortening the effective focal length. The weight difference will simply be a bit of extra 2" barrel and therefore not a lot of weight.

Could be wrong though...

Russell

[Andrew*]

I'd imagine the 1.25" examples all weigh a similar amount.

I could be off the mark here, but I imagine the difference in length is occupied by air as the different focal lengths are achieved by moving the leading Smythe doublet lens group (basically a negative doublet barlow) away from the other six elements to increase magnification, thereby shortening the effective focal length. The weight difference will simply be a bit of extra 2" barrel and therefore not a lot of weight.

Could be wrong though...

Russell

I reckon you're right there Russ. That's usually the case.

[bingevader]

Hmmm, 2" fittings but not "true" 2" EPs, I seem to remember trying to have this discussion recently!

It's why I think including the field stop measurement would be much more useful than just giving the barrel dimension.

Cheers

[John]

Most of the range don't need to be "true" 2" eyepieces as the field stop can be accommodated within a 1.25" barrel. The 2" skirt is there to allow owners to get the security of a 2" drawtube fitting because these are quite heavy eyepieces.

[emadmoussa]

Im starting to think maybe the 3.5mm is an overkill for the 80ED?

[John]

Im starting to think maybe the 3.5mm is an overkill for the 80ED?

171x is a tad over the normal "top end" for an 80mm scope but the ED's have good objective lenses and, on the right subjects, you can really push things. I use 257x and even 300x with my ED120 more often than I expected.

[Stu]

It's probably at the high end of what's useable on a good night on planets. On doubles and the moon it would be fine I'm sure.

I use a 3.5 type 6 nag in my Stellarvue 80ED which is slightly faster at f7 so it gives x160 and that is about the maximum I normally use on reasonable nights. The exit pupil is pretty small too so floaters can start to be an issue

Perhaps a 4mm might be useable more often?

Stu

[Andrew*]

Personally I think you will be fine with a 3.5mm on the ED80. I used a 3mm when I had an ED80 and found the view fine.

[emadmoussa]

Thanks, guys. I guess like Stu said, it'll be good for double stars -- and perhaps planets.

Thinking about it, I once used a 2.5x barlow with the Hyperion 8mm and I could achieve focus despite the narrow field of view.

[Stu]

It'll focus all right, just really a question of how useable how often. What's your next ep below this?

[emadmoussa]

It'll focus all right, just really a question of how useable how often. What's your next ep below this?

That's the lowest number EP I've got - or will receive. Can't go any lower since it'll be a total overkill for my other scopes. I think I've got the range now: Hyperion 5mm / 8mm , Panaroma 15mm, Maxvision 20mm, ES 24mm, cheap 2" SW 28mm and Baader Scopos 35mm. I don't think filling the gaps will make much of a difference? I'm not counting the Plossls in that --

[John]

With a 3.5mm you will have a pretty comprehensive set - I can't see any further gaps myself

[Stu]

By below I meant lower mag, longer f/l ep, agreed that you wouldn't want any short than this.

You've got a pretty good range now, looks good

Stu

[bingevader]

Most of the range don't need to be "true" 2" eyepieces as the field stop can be accommodated within a 1.25" barrel. The 2" skirt is there to allow owners to get the security of a 2" drawtube fitting because these are quite heavy eyepieces.

Which, as I suggested previously, is the case for some of the big meaty TV EPs too!

What we have is a whole range of EPs with field stops varying from less than 1.25" to 2" which are accommodated in 2 standard barrel sizes for ease of use.

It would just be far more useful to include the field stop measurement as well as simply trying to classify them as 1.25" or 2" EPs.

Cheers

[emadmoussa]

My 3.5mm has landed today - thanks FLO.

I can give you few close shots in case you're wondering about the build quality, size and weight.

I have to say it's slightly bigger than I expected, almost as big as the Baader Scopos 2" 35mm, but much lighter. The rubber encasing is very nice and provides a better grip of the EP. All in all it's a high quality piece of kit.

First light is yet to come.

[Damo636]

Congrats on the new addition!

[AlexB67]

Love the shape, as I said earlier in the thread more as a joke, but it looks so aerodynamic, but also they made it light, really like a made in wind tunnel eyepiece design . I suppose thinking about going forward in future and constant development in materials, apart from some glasses perhaps to keep costs down, everything else such as the casing, the weight of these things can be minimised at lesser costs, the heavier beasts will become a thing of the past in time to come I suspect.

[Andy_E]

I'm still surprised they're quite so heavy. With WO UWANs, Nirvanas and naglers all coming in at below 300g (the 1.25" ones) at more than twice the weight for the equivalent EP it just seems a bit extreme. I know it's not really a fair comparison as the design of these EPs is fairly different, but still wonder if it will cause an issue. Having said that, if they perform optically I imagine they'll be a very popular EP. Out of interest, anyone got any ideas on the actual optical design of these?

[John]

Thats a massive 3.5mm

Makes my 3.5 XW seem dainty and I thought that was a clunker !

Makes you wonder what sort of glass is in there - the XW has 8 elements and a similar spec but is 405g

[Mr Spock]

Interesting. The LVW is only 452g and they are huge 8 element jobbies.

I'm looking forward to seeing a performance comparison with other similar eyepieces.

[luminova11]

I'm also looking forward to a review on these. I like the look of them but need to know if the optical quality is enough to outweigh the versitility of the hyperions.