A Market for Quality Orthos?

[jabeoo1]

It is amazing how many brands of Orthosopic eyepieces have been put to rest.  Why don't the successful modern brands engage in product lines to match the build quality of the discontinued Pentax smc xo 5mm?  When these rarely do come up they can change hands beyond the RRP price they were when new. 

So why does the 2nd hand market remain vibrant and at the potential profit of modern wider-field EP makers?

 

[michael.h.f.wilkinson]

Apart from FOV, the eye relief (ER) of the classic Abbe ortho is very poor at the shorter focal lengths. These shorter focal lengths have become more important because scopes have become a lot faster. When I started F/10-F/16 was quite normal, now scopes are easily F/4-F/6. The Pentax XO 5mm is actually a different design (5 element, three groups). What with (much) better coatings than in the past, the need to restrict yourself to just two groups has practically gone

[mikeDnight]

As Michael mentioned, in the short focal lengths the ortho's aren't so comfortable, also their edge of field performance can be pretty awful in a scope with a fast F ratio. So, in comparison to say a 5mm or 3.5mm XW, a similar focal length ortho in a fast scope would be a pretty miserable eyepiece to use. I love the orthoscopic but in my fast refractor I would use a barlow/ortho combination for best results. By using a long to medium ortho and a barlow, the field and comfort are much preferable. I use ortho's in my binoviewer but there's also a 2X Barlow screwed to its nosepiece. The resultant view is better in my opinion than the view through a first class 5mm XW. Without the Barlow the ortho's are not so good!

Another problem is that a high end ortho will cost as much if not more than an XW but without the comfort if its a short fl. Comfort counts for a lot when studying fine detail!

Buy a 1.6X extender Q for your FC100D and use it at F11.8 along with a cheap ortho set and you'll get stunning views. It's only money! £££££ (Certainly cheaper than a set of XW's).

With the evolution of some excellent eyepieces designed specifically for fast scopes, I think the ortho has had its nose shoved out, which is a real shame! These modern wide field eyepieces use internal barlows in their design, so why shy away from using a barlow along with a long fl ortho or plossl? Modern  barlows are great and don't have a detremental effect on image quality. 

Mike

[michael.h.f.wilkinson]

God points. I am sometimes amused by the people who bash modern planetary EP designs (like the Delos and XW) consisting of a negative Smyth lens in front of a group of lenses that functions more or less as a classic EP. They claim these cannot perform as well as (Abbe) orthoscopics, due to the large number of glass-air interfaces. They then happily add a Barlow (at least two air-glass interfaces) or a tele-centric lens like a PowerMate (4 interfaces) in front of a longer F/L ortho for more comfort. Really, a Barlow is just a Smyth lens, but the Smyth lens can be designed to be matched to the other lenses in the planetary EP, whereas the Barlow typically isn't. Yes, extra glass-air interfaces can yield more scatter, but my Pentax XWs and Delos EP beat my older orthoscopics, because the former have top-of-the-line multi-coatings, whereas my old circle-T had single MgF2 coatings

[John]

I've used lots of orthos and quite a few wider field eyepieces for planetary observing. With today's coatings and glass types the wider field, longer eye relief eyepiece can deliver performance to rival a good abbe ortho most of the time I reckon.

There was a surge in ortho availability a little while back. Shortly after the Baader GO production was stopped due (apparently) to the impact of the Japan earthquake / tsunami, the eyepiece design re-appeared again under brandings such as Astro Hutech, Fujiyama and University HD (2nd time around for that name !). They were really competant orthos and, IMHO, were virtually identical in performance to the Baader GO's. I'm not sure that they sold in great numbers though.

I suspect the abbe ortho design will always be around in some form or other though. The Pentax XO was not an abbe ortho design. It did share many of the performance characteristics of the design though:

I wonder if the Vixen HR Planetary eyepieces are an effort to fill a similar niche to the XOs ?. Just need some slightly longer focal lengths now !:

https://www.firstlightoptics.com/vixen-eyepieces/vixen-hr-planetary-eyepieces.html

[Timebandit]

I do like the Ortho but IMO the days are numbered for the Ortho being wanted in any significant way to make it worthwhile for manufacturers.

In the past  an Ortho was a great way to get a tack sharp eyepiece for your scope even though the fov was narrow and eye relief tight. But the Ortho was wanted due to its pure observation image quality.

With the technology and better manufacturing ability we now have eyepieces out there that can give Ortho tack sharp views but with fov of around 70d and 20mm eye relief such as the great Pentax XW . Therefore people do not now have to suffer the detrimental side of an Ortho, fov, eye relief to get Ortho like tack sharp image performance. And it's like everything that evolves that people will not suffer the down sides of an eyepiece if there is another eyepiece on the market that will "do it all  ".  Therefore IMO with all the high end tack sharp, great fov , wide eyepieces on the market then I consider the days of the Ortho are numbered. I personally do like the Ortho but that maybe on a sentimental side, as IMO the Pentax XW have tack sharp Ortho image quality but also they are so comfortable to use, something you cannot say about an Ortho especially at the higher magnification end of the spectrum.

In my opinion the only Ortho that may have a call for against the modern wide field of view with great eye relief eyepiece , is if a manufacturer makes a ZAO equivalent for sensible money. If a manufacturer did this then I am sure there would be a good demand, and  I would be first in the queue for such a eyepiece for detailed planetary and lunar viewing.

[jabeoo1]

21 hours ago, mikeDnight said:

Buy a 1.6X extender Q for your FC100D and use it at F11.8 along with a cheap ortho set and you'll get stunning views. It's only money! £££££ (Certainly cheaper than a set of XW's).

Mike

Interesting point Mike.  The option for a f/11.8 is enticing.  Did you revert back from the f/11 setup to the using the scope at f/7.4 for any particular reason?  

[jabeoo1]

14 hours ago, Timebandit said:

......the Pentax XW have tack sharp Ortho image quality but also they are so comfortable to use, something you cannot say about an Ortho especially at the higher magnification end of the spectrum.

I really do need to try a Pentax XW sometime.  Everyone seems to be very enthusiastic about them.  On recent reading up its a close call between a 5mm Delite and a 5mm XW these days. 

[mikeDnight]

2 hours ago, jabeoo1 said:

I really do need to try a Pentax XW sometime.  Everyone seems to be very enthusiastic about them.  On recent reading up its a close call between a 5mm Delite and a 5mm XW these days. 

I've not used a delite though I have used many TeleVue eyepieces over the years. So far I've not seen any of their eyepieces provide the same purity of image that the XW's do. Also, because I use a Tak prism, no TeleVue eyepieces locks down securely due to their stupid, unnecessarily deep undercuts. If you want to grab some XW's you'd better be quick, as I've heard the line is no longer in production which is very sad.

Mike

Mike

[alan potts]

I feel the one great thing that the likes of Hutech and BGO have going in their favour is the quality they deliver for the cost. The others with wider FOV mentioned cost well over 200 pounds new and even the newer De Lite models are in the same ball park area. Yes they do deliver very high quality views on like for like nights but cost more than twice the price. Whether Pentax XO's are that much better, I have never seen one to know but suspect the difference is minor. To some that small plus is worth paying for, personally I do prefer the wider view and longer relief but I am happy to keep and use my Hutechs and BGO's.

Alan

[jabeoo1]

45 minutes ago, alan potts said:

...........personally I do prefer the wider view and longer relief but I am happy to keep and use my Hutechs and BGO's.

Alan

What scope/s do you use these in Alan?  

Tracked or untracked ? 

James

[nightfisher]

Im still a great fan of the traditional ortho, yes i gave up my beloved circle T collection this was due to having a a good few that were just not getting used and i felt it was better to sell the lot as a set rather than splitting them up, i now have a very good Antares HD 9mm and this is being joined by its little brother, the 7mm

[spaceboy]

1 hour ago, alan potts said:

I feel the one great thing that the likes of Hutech and BGO have going in their favour is the quality they deliver for the cost. 

This is where I always had high praise for BGO. I always felt there was no beating the quality and contrast in the views for as littles as £50 used and even when they were available for £87 new they still gave the best bang for buck. Sure they are not the best feature packed eyepiece on the market and certainly not the most comfortable to use but as far as views go they are up there with the best.

[jetstream]

23 hours ago, John said:

I've used lots of orthos and quite a few wider field eyepieces for planetary observing. With today's coatings and glass types the wider field, longer eye relief eyepiece can deliver performance to rival a good abbe ortho most of the time I reckon.

There was a surge in ortho availability a little while back. Shortly after the Baader GO production was stopped due (apparently) to the impact of the Japan earthquake / tsunami, the eyepiece design re-appeared again under brandings such as Astro Hutech, Fujiyama and University HD (2nd time around for that name !). They were really competant orthos and, IMHO, were virtually identical in performance to the Baader GO's. I'm not sure that they sold in great numbers though.

I suspect the abbe ortho design will always be around in some form or other though. The Pentax XO was not an abbe ortho design. It did share many of the performance characteristics of the design though:

I wonder if the Vixen HR Planetary eyepieces are an effort to fill a similar niche to the XOs ?. Just need some slightly longer focal lengths now !:

https://www.firstlightoptics.com/vixen-eyepieces/vixen-hr-planetary-eyepieces.html

I am very satisfied with my current eyepiece selection, but, the 5mm XO is an eyepiece that I still have a big desire for.

John, could you please find me one?

[John]

4 hours ago, jetstream said:

I am very satisfied with my current eyepiece selection, but, the 5mm XO is an eyepiece that I still have a big desire for.

John, could you please find me one?

I've only been able to find the occasional 2.5mm for sale Gerry. The 5mm has been out of production for quite a while I think I've only seen one for sale in the past few years. If I find a couple for sale I'll get right back to you though

 

[alan potts]

13 hours ago, jabeoo1 said:

What scope/s do you use these in Alan?  

Tracked or untracked ? 

James

I have a wide selection of scopes from an 18 inch Dob right down to a 70mm APO that sits piggyback on the 12 SC. I use orthos mainly in the driven scopes. On the 12 inch SC the the focal length is a bit much for most of my orthos but I have used the 12.5mm and 18mm, this is also true of the 180mm Mak. Mainly though the range from 5mm ortho are used with the 190mm Mak/Newt and the 115mm APO, both being shorter F/Ls. I have tried a few in the Dob but the FOV is so small for my nudging skills, this is where for me Ethos is king and any other eyepiece rarely gets a look in apart from the 31mm Nagler.

Alan

[mikeDnight]

On 07/12/2016 at 12:01, jabeoo1 said:

Interesting point Mike.  The option for a f/11.8 is enticing.  Did you revert back from the f/11 setup to the using the scope at f/7.4 for any particular reason?  

Yes! Although the 1.6x extender Q was utterly flawless from an optical stand point and in no way proved to be detremental to the image quality, it was a fiddly  contraption with various extensions. The result was that if I wanted to change from F11.8 back to F7.4 for greater field, and more so back to F11.8 in the dark, it was a bit of a chore. So, I tested the scope at both F ratios to see if there was any advantage of one ratio over the other. What I found was that with the Q attached, there was no breakdown in image quality even at X474. Without the Q attached and working at its native F7.4, the scope was equally sharp and colour free. I could reach a max magnification of X296 without the Q which is more than adequate for my purposes, while retaining its rich field ability without fiddling around in the dark. The FC100DC proved to be as optically perfect at F7.4 as it was at F11.8 and so i felt I had no further use for the extender Q.

The Q did allow some magical medium power views of the lunar surface through my binoviewer though, and there are times I wish I hadn't sold it, but ultimately the FC is perfect with or without it. Perhaps theres a psychological slant to using the scope at F11.8. The only other advantage the Q had was to perform as a most perfect image amplifier, allowing higher powers to be used per given eyepiece. As a party trick and with the Q attached, I'd show visitors to my observatory Venus at X474, razor sharp and colour free when high against a twighlight sky. ?

Mike 

[jabeoo1]

On 12/6/2016 at 13:22, michael.h.f.wilkinson said:

The Pentax XO 5mm is actually a different design (5 element, three groups). 

Ah yeah, apart from that  .........oops