Oh dear, green & black symptoms ahoy...

[TwoPi]

Hi folks. Looking for some more advice...

I've been thinking about upgrading the 10mm in my EP collection for a while (I have the standard SkyWatcher SP) as irritatingly it is the one that I use most frequently behind my 24mm UWA, and it is noticeably poorer & less comfortable to use than the rest of my eyepieces.

Given its regular use and having read countless threads about the wonders of those green & black jobbies you can get, I think I've just about convinced myself to buy a 10mm Delos to see what all of the fuss is about.

When I consider my eyepiece line-up as a whole, I'm fairly satisfied with the range I've got. However, I do sometimes wish I could push it beyond the 200x magnification I get with my WO 6mm, particularly when looking at the Moon, Jupiter & Saturn. Given that this will only be for particularly steady nights I'm reluctant to purchase another eyepiece (say a 5mm or maybe even a 3-6mm zoom - though that's probably over the top?).

After reading Russell's excellent review of the ES 1.25" 2x focal extender here, I'm drawn towards this kind of solution as for the price of one eyepiece I effectively would add 8mm, 5mm and possibly 3mm (though presume this last one wouldn't be much use) to my collection, plus a 12mm if I bought a 2" focal extender.

So my questions are:

1. If I was to go for a focal extender then is there any appreciable difference in quality between the TV Powermate and ES variants?

2. I can't make my mind up whether to go for a 1.25" or 2" focal extender - it would be nice to be able to use it with all of my eyepieces but not sure the extra weight and cost is worth it just for my one 24mm 2" EP, especially given the resultant 12mm will be very close to my 10mm. That said, if I wanted to go down the Powermate route then I guess I would have to go for the 2" as the 1.25" version is 2.5x and so will mean I don't get the 5mm / 250x magnification I'm after.

3. If I do end up going the ES option, can you buy them in the UK or Europe, or do you have to go to the US? Any recommendations on which retailer?

4. Would anyone recommend not going for a focal extender and instead just getting a 5mm or maybe the Nagler 3-6mm zoom for the rare occasions my seeing is good enough?

Thanks as ever for your help!

Cheers,

[Stargazer_00]

It depends on you really.

First off the 10mm Delos is simply sublime. Like you I've always found the 10mm slot is a good one to fill and it's great knowing that you have it filled with the best possible eyepiece in that focal lengh.

In terms of getting higher magnficiations, it depends on you really. You could get an 12mm Delos as well and get a powermate for 100x/200x, and/or an 8mm Delos for 150x/300x.

I'd expect the ESFE one to be not as good as a 2x powermate. Comparing the ES eyepiece quality to the TV Delos quality I'd expect the same quality differences between the ESFE and a Powermate. Personally

I just recently got a Nagler 3-6mm Zoom and it's perfect for me. I got it to use primarily in my 750mm focal length scope where it gives 125x to 250x, a lovely range of versatility from a single eyepiece here but it's also shown to be surprisngly fun in my 1650mm focal length scope too. Time will tell if it has much use in my main scope but I'd expect it to be amazingly fun on the moon and planets, I'd expect it to be might useful on Mars later this year when that rolls around into early evening view.

Personally having a parfocal zoom could be the most fun thing I've thing ever had in this hobby. You get the target in focus at the lowest magnification, get it focused then simply wind up the mag. Unlike other zooms where you need to refocus once you move the magnficiation, this eyepiece holds perfect focus across it's range making it the most fun. I wish there was something around 8-14mm that worked this way, I'd pay a grand for that fun/functionality.

[Moonshane]

I have used a TV 2.5x powermate and they are very good but I find it a faff changing around 'constantly' (it's not that bad really.

My recommendation for you would be a used 10mm Radian if you can get one and a 6-3mm Nagler zoom if you can afford one and assuming you are happy with the eye relief of your existing 10mm 'plossl'.

with what you already have you'd be pretty much covered.

[Damo636]

Personally having a parfocal zoom could be the most fun thing I've thing ever had in this hobby. You get the target in focus at the lowest magnification, get it focused then simply wind up the mag. Unlike other zooms where you need to refocus once you move the magnficiation, this eyepiece holds perfect focus across it's range making it the most fun. I wish there was something around 8-14mm that worked this way, I'd pay a grand for that fun/functionality.

There is....

http://www.apm-telescopes.de/en/Eyepieces/Zoom-Eyepieces/Leica-Zoom-eyepiece-Vario-8.9-17.8-mm-ASPH.-1.25.html

[TwoPi]

Well I suppose you did ask Graham

Regarding Shane's point on eye relief, I can manage with the SW 10mm eye relief but I do really enjoy the 20mm I get with the WO 6mm eyepiece; one of the reasons I am leaning towards a Delos. Plus if I did go down the 2x focal extender route then I'd be happily enjoying 250x views with the same comfort.

That said, two votes for the 3-6mm zoom instead of a focal extender already, not what I was expecting (but then that was the point of asking for your views)! Given it would be giving me 200-400x views, I was thinking I wouldn't get too much use out of it. But then again if I then used it instead of my WO 6mm then I would be using it a lot more, and could then sell the 6mm. Though again, I'd be going back to reasonably tight eye relief with the Nagler Zoom...

Hmm.

[Stargazer_00]

I woudn't say get the 3-6mm zoom before a 10mm Delos.

I'd probably say get an 8mm Delos instead of the 3-6 zoom as well in fairness. And probably the 12mm Delos!

Then, and only then, I'd think "do i want a 2x powermate or a 3-6 zoom. The powermate would give 4, 5 and 6 only but with glorious 72 degree afov, and the 3-6 zoom gives an analogue range of focal lengths between 3mm and 6mm but with a reduced afov" A much more sensible (and expensive) dillema.

[estwing]

powermate over the zoom everytime in this camp....

[Pig]

From what I have read in the forum the length of the Powermate together with the length of the eyepiece can be quite a stretch and a tad on the heavy side, this might be worth some consideration

[TwoPi]

From what I have read in the forum the length of the Powermate together with the length of the eyepiece can be quite a stretch and a tad on the heavy side, this might be worth some consideration

Yes, I am a bit worried about this, hence why I was leaning towards a 1.25" focal extender as it's almost a third of the weight (comparing the ES extenders). That said, mine's a GOTO so balance not as critical as a regular dob, though the motor still needs to be able to lift the bloomin' thing!

[TwoPi]

I woudn't say get the 3-6mm zoom before a 10mm Delos.

I'd probably say get an 8mm Delos instead of the 3-6 zoom as well in fairness. And probably the 12mm Delos!

Then, and only then, I'd think "do i want a 2x powermate or a 3-6 zoom. The powermate would give 4, 5 and 6 only but with glorious 72 degree afov, and the 3-6 zoom gives an analogue range of focal lengths between 3mm and 6mm but with a reduced afov" A much more sensible (and expensive) dillema.

So would I be right in thinking you like the Delos EPs? Following that line of thought, would I not be better off just buying a 10mm Delos and a 4.5mm Delos?!

Seriously though, my assumption is that there's not much point in me buying 5mm or less given 250x+ magnification isn't going to get a lot of use. With a focal extender I will at least use that a reasonable amount (unless it's too heavy or too much faffing to swap it in and out).

I think I'm just talking myself around in circles now.

[jetstream]

Hi 2Pi, get a Delos and give it a try,they have amazing light transmission,contrast,etc.I personally like what different eyepiece designs give me for viewing experiences,as an example I have the 3-6 Nagler zoom and a 6mm Delos,very different yet both excellent.Looking at ET the other night the 6mm Delos gave a fantasic immersive view of this object,and yet the zoom was great, just different.Each one in my growing collection has a role,even if mags are close in a few.Any of those Delos would serve you well,as would the zoom.What do you use for an eyepiece with your UHC & upcoming Astronomik OIII filter? Oh and the21mm Ethos are on sale....!

[John]

The Powermate 2.5x is a 1.25" device, weighs around the same as the ES focal extender and is around the same size. It's the 2" "x Powermate that adds a fair bit of weight and even more length. Optically superb though.

[russ.will]

1. If I was to go for a focal extender then is there any appreciable difference in quality between the TV Powermate and ES variants?

John would be good to ask on this one, as he has had TV PMs and I lent him my ES FE as I was interested to hear his thoughts.

2. I can't make my mind up whether to go for a 1.25" or 2" focal extender - it would be nice to be able to use it with all of my eyepieces but not sure the extra weight and cost is worth it just for my one 24mm 2" EP, especially given the resultant 12mm will be very close to my 10mm. That said, if I wanted to go down the Powermate route then I guess I would have to go for the 2" as the 1.25" version is 2.5x and so will mean I don't get the 5mm / 250x magnification I'm after.

I personally think that you're best off considering a PM/FE to generate focal lengths you don't often use and concentrate on gradually amassing EPs to fill the regularly used slots. I had a 2" Barlow that seemed like a good idea for the reasons you state, but ended up being ignored because of the continual hassle of swapping the Barlow, EPs and 1.25-2" adaptors back and forth.

In the end, I bought the 1'25" FE for simply generating the occasional use planetary focal length EPs. When I decide I'm going to go looking at planets, I insert it in the focuser and stick to simply switching between 1.25" EPs.

As such, I'd say an good EP in the 11-13mm range is a must, because it will get used a lot in a 1200mm FL Newt. My 11 & 14mm ES82s are by far and away my most used EPs on a wide range of subjects and I'd get reet hacked off if I had to keep faffing with a Barlow/PM/FE to get there!

3. If I do end up going the ES option, can you buy them in the UK or Europe, or do you have to go to the US? Any recommendations on which retailer?

I haven't tried them all, but Hands On Optics have been superb for me, with very good shipping charges. The one warranty issue I had resulted in the replacement being on my doorstep within a week, which beat both of my two UK warranty claims by 3 months - They weren't simple issues to be fair, but that's Skywatcher for you!

Russell

[alan potts]

Don't fight it give and buy the 10mm Delos, you will not regret it!

Alan

[rwilkey]

Hi Gav, the WO 6mm ep is a good one, one of my most used high mag, you would need to spend a lot of cash to better that one. Explore Scientific are sold in the UK by Telescope House and the 6.7mm 82 series is the closest spec to your 6mm suggestion, Here: http://www.telescope..._Eyepieces.html. Well worth the money though I bought the three I have s/h. Highly recommended, but bear in mind the eye relief is not great but passable in my view, not as bad as plossls. If all else fails then by all means go down the green & black route, which I have not tried except for the 32 plossl, a great ep I should say. Good luck in your choices!

[TwoPi]

Great advice as ever and plenty to think about. Still keen on the Delos 10mm (providing I either go for 2x FE or a dedicated

[TwoPi]

^^^

No idea what happened there, I'd written a longish reply but seem to be having trouble posting whilst on the move. Will try again later when not travelling...

[TwoPi]

Right, now I've stopped moving I'll try again!

Still keen on the Delos 10mm (providing I either go for 2x focal extender or a dedicated <6mm high power eyepiece option).

After reflecting on Russell's, Shanes' & Shaun's comments, I think if I go down the FE route then I want to keep it to 1.25" EPs only - effectively just using it for solar system viewing so that I'm not constantly swapping between 2" and 1.25" adapters AND the focal extender AND different eyepieces. As John says, that will also keep the weight / balance problems to a minimum.

However, if I go with a Powermate then this means a 2.5x FE rather than 2x, which in turn means slightly different eyepiece choices.

So I guess my remaining question on the FE front is whether the 1.25" 2.5x Powermate is a better performer than the 1.25" 2x ES version? It sounds like John, you might have a view on this?

Then I just need to make my mind up whether to go FE at all or go crazy and get something like the 3-6mm zoom!

Thanks again for all your help and views.

[TwoPi]

What do you use for an eyepiece with your UHC & upcoming Astronomik OIII filter? Oh and the21mm Ethos are on sale....!

Very good Gerry - stop trying to tempt me! It will be a least another couple of weeks before I succumb to your further suggestions...

[Pig]

The Nagler 3-6mm zoom is brilliant even with my 2350mm focal length mind you being able to focus at the 3 & 4 mm setting is down to my dual focuser, without it I would not find it possible to do without motorised assistance.

[John]

..... mind you being able to focus at the 3 & 4 mm setting is down to my dual focuser, without it I would not find it possible to do without motorised assistance....

Presumably really, really good seeing conditions are also required for 588x - 783x to be any use at all Shaun ?. My 12" Orion Optics dob has excellent optics but I don't find over 400x adds anything useful except on binary stars and then only under the very best conditions.

[TwoPi]

Hi John, any views on how the 1.25" 2x ES focal extender compares in terms of performance with the 1.25" 2.5x Powermate?

Cheers,

[Pig]

Presumably really, really good seeing conditions are also required for 588x - 783x to be any use at all Shaun ?. My 12" Orion Optics dob has excellent optics but I don't find over 400x adds anything useful except on binary stars and then only under the very best conditions.

Sorry I failed to mention the Moon was the target

As unbelievable as it may seem at 5mm+ the moon is as crisp as you could wish,despite the very high mag

[John]

Sorry I failed to mention the Moon was the target

As unbelievable as it may seem at 5mm+ the moon is as crisp as you could wish,despite the very high mag

I can believe it - the Moon seems to absorb very high power better than most things we view.

[Pig]

I couldn't believe it myself John it was pretty remarkable I had to check the magnification twice on the calculator.