Orthoscopics?

[Dude_with_the_tube]

Circle T`s came as vulcano tops .

 

[Mak the Night]

58 minutes ago, Dude_with_the_tube said:

Circle T`s came as vulcano tops .

 

I think I've seen some of those. Some people prefer the volcano top with ortho's, although I suppose only the really short focal length ones really need it.

[Dude_with_the_tube]

i would say it is more of personal preference really. Some like vulcano tops,some flat tops.Circle t`s came as vulcanos,Meade Rg`s same,Zeiss Zao 1 and 2,BGO,Astrotech,UO as flat tops.UO(university optics)where also made as vulcano tops.There where quite a few other orthos made under different brand names,like Antares,Celestron,Vixen etc.Orthos where and i think still are very popular for planetary observers. 

[John]

I found that the "volcano top" shaped orthos made it easier to access the eye lens of the shorter focal lengths. Optically the more recent "flat top" Baader GO / Astro Hutech / Fujiyama orthos show slightly less light scatter and a little more transmission than the "volcano tops" to my eyes but the eye lens can be hard to locate and hold (for me at least) in 6mm focal lengths and below. My scopes are undriven though, which might not help with that !

The "volcano top" orthos used to be on the used market for rather low prices at one point which made them somewhat of a bargain. Their prices seem to have crept back up to closer to the more recent flat top designs now they are out of production.

 

[Mak the Night]

14 minutes ago, Dude_with_the_tube said:

i would say it is more of personal preference really. Some like vulcano tops,some flat tops.Circle t`s came as vulcanos,Meade Rg`s same,Zeiss Zao 1 and 2,BGO,Astrotech,UO as flat tops.UO(university optics)where also made as vulcano tops.There where quite a few other orthos made under different brand names,like Antares,Celestron,Vixen etc.Orthos where and i think still are very popular for planetary observers. 

There are a few ortho's now on the market. I think they may be coming back into fashion. Talking of Celestron ortho's, I've never seen one, but I found this online:

http://ensoptical.co.uk/celestron-7mm-ortho

[Mak the Night]

10 minutes ago, John said:

I found that the "volcano top" shaped orthos made it easier to access the eye lens of the shorter focal lengths. Optically the more recent "flat top" Baader GO / Astro Hutech / Fujiyama orthos show slightly less light scatter and a little more transmission than the "volcano tops" to my eyes but the eye lens can be hard to locate and hold (for me at least) in 6mm focal lengths and below. My scopes are undriven though, which might not help with that !

The "volcano top" orthos used to be on the used market for rather low prices at one point which made them somewhat of a bargain. Their prices seem to have crept back up to closer to the more recent flat top designs now they are out of production.

 

Yeah, I really find Plossls less than 8mm hard work, I should imagine ortho's are no easier even with possible better eye relief. I suppose anything rare that comes back into fashion will command high prices. 

[John]

Orthos had a surge of popularity a year or two back but I believe that they are not such good sellers now.

When they are unfashionable you can pick some lovely eyepieces up for low use prices

[jetstream]

I don't understand why they lack popularity at times, the views they give are superb and the better the seeing gets the more they can pull away IMHO. I have no problem with a 5mm ortho in my truss dob , and the views are worth the nudging.

[Mak the Night]

35 minutes ago, John said:

Orthos had a surge of popularity a year or two back but I believe that they are not such good sellers now.

When they are unfashionable you can pick some lovely eyepieces up for low use prices

And there was me thinking I was trendy with my new ortho's and I find out they're so 2014 lol!

[Mak the Night]

23 minutes ago, jetstream said:

I don't understand why they lack popularity at times, the views they give are superb and the better the seeing gets the more they can pull away IMHO. I have no problem with a 5mm ortho in my truss dob , and the views are worth the nudging.

You're in luck! They're on sale: http://www.firstlightoptics.com/japanese-made-eyepieces/hutech-orthoscopic-eyepiece.html

[jetstream]

Now if you could only find me a Pentax 5mm XO...  I have 5 ortho's atm and use them frequently, great views.

[Piero]

Interesting thread and nice review inside.

I have a TV 20mm plossl which is a very good EP to me. I find 50 deg a bit claustrophobic though.. This is the reason why I don't go for the cheap bco. On the other hand, I'm a bit tempted due to the constant positive opinions by members.

It's good to have multiple and affordable choices out there.

Enjoy your views!

[Mak the Night]

11 hours ago, jetstream said:

Now if you could only find me a Pentax 5mm XO...  

I can find a picture of one! 

Which is about the best I can do lol. They look nice and I believe they had 44° FOV's.

[Mak the Night]

10 hours ago, Piero said:

Interesting thread and nice review inside.

I have a TV 20mm plossl which is a very good EP to me. I find 50 deg a bit claustrophobic though.. This is the reason why I don't go for the cheap bco. On the other hand, I'm a bit tempted due to the constant positive opinions by members.

It's good to have multiple and affordable choices out there.

Enjoy your views!

The 20mm TV Plossl was one of my favourite eyepieces until it essentially got replaced by a 68° 19mm Panoptic.  My 8mm, 11mm and 20mm TV Plossls don't really see that much use these days but I think Plossls are still relevant depending on what you are viewing. For low power views of open clusters or objects such as M42 I sometimes prefer a 25mm Plossl over the 24mm Panoptic. I think the 50° FOV can be limiting although a lot depends on field stop and eye lens size. Plossls can vary a bit with this which is generally why I use TeleVues.

There isn't a huge difference between the 18mm AH ortho and the 20mm TV Plossl in overall size. The TV is a little bit more expensive (a few pounds Sterling) but you do get a rubber eye guard, a rubber barrel grip and a tapered barrel safety undercut. 

TeleVue claim: ‘Tele Vue Plössls deliver sharper images than any other brand of 4 or 5 element "Plossl" or Orthoscopic designs’ and though I don't deny their remarkable quality I couldn't detect any difference in sharpness between the Astro Hutech 18mm and the TeleVue 20mm. 

 

[jetstream]

14 hours ago, Piero said:

Interesting thread and nice review inside.

I have a TV 20mm plossl which is a very good EP to me. I find 50 deg a bit claustrophobic though.. This is the reason why I don't go for the cheap bco. On the other hand, I'm a bit tempted due to the constant positive opinions by members.

It's good to have multiple and affordable choices out there.

Enjoy your views!

Don't be fooled by the price of the BCO Piero, the glass in these things are superb as are the coatings. They give black and green more than a run for their money IMHO.... Sorry for the "heresy"

[alan potts]

17 minutes ago, jetstream said:

Don't be fooled by the price of the BCO Piero, the glass in these things are superb as are the coatings. They give black and green more than a run for their money IMHO.... Sorry for the "heresy"

I have the doll and the pins out now.

[YKSE]

3 hours ago, Mak the Night said:

 

TeleVue claim: ‘Tele Vue Plössls deliver sharper images than any other brand of 4 or 5 element "Plossl" or Orthoscopic designs’ and though I don't deny their remarkable quality I couldn't detect any difference in sharpness between the Astro Hutech 18mm and the TeleVue 20mm. 

I would like to think that Televue's claim are meant astigmatism suppression in the field (outer edge), especielly in faster scopes, since Televue has its patent in plossl design, USpatene4482217.

On the other hand, Televue plossls are not true plossls (just as all the other nowadays' plossl), they're symetric doublet (achromat pair), and from the pictures in the middle of this page

http://www.telescope-optics.net/eyepiece_aberration_2.htm

We can see that for the focal ratio, Monocentric has best on-axis sharpness, ortho comes second, thereafter come achromat pair and könig.

[jetstream]

40 minutes ago, alan potts said:

I have the doll and the pins out now.

May I please redeem myself by saying nothing out contrasts an Ethos?

[Mak the Night]

21 minutes ago, YKSE said:

I would like to think that Televue's claim are meant astigmatism suppression in the field (outer edge), especielly in faster scopes, since Televue has its patent in plossl design, USpatene4482217.

On the other hand, Televue plossls are not true plossls (just as all the other nowadays' plossl), they're symetric doublet (achromat pair), and from the pictures in the middle of this page

http://www.telescope-optics.net/eyepiece_aberration_2.htm

We can see that for the focal ratio, Monocentric has best on-axis sharpness, ortho comes second, thereafter come achromat pair and könig.

I honestly thought it was just advertising spiel by TeleVue. Although, the build quality of the eyepieces isn't in dispute. I thought a Plossl actually was an achromatic pair. I'm not that up on the history though. That link about optics is good though, I've bookmarked it. Thanks. 

I must say that I'm impressed with my new ortho's. 

[Mak the Night]

20 minutes ago, jetstream said:

May I please redeem myself by saying nothing out contrasts an Ethos?

Oh no ... you've got me jonesing for an Ethos again now lol! 

[jetstream]

They work extremely well.

[alan potts]

Well there is nothing like an eyepiece contrast, Orthoscopic and Ethos, bit like chalk and cheese FOV wise. Having both I do like the wide field E's on the Dob for just the user friendlyness of them but orthos come into their own on the driven scopes with planets. In fact the only thing I am not over keen on is that tight ER on the 5mm, so I don't know what the 4mm will be like. I then only find this is time limiting as to how long you can use them.

[Piero]

3 hours ago, jetstream said:

Don't be fooled by the price of the BCO Piero, the glass in these things are superb as are the coatings. They give black and green more than a run for their money IMHO.... Sorry for the "heresy"

Hi Gerry, I apologise, I should have clarified this better. I wasn't meaning that bco are cheap, likely not good. I know they are very very good, as one can read from your and other members' experiences. 

I was just saying that I feel 40-50 deg quite claustrophobic and therefore I feel that I would not appreciate them. Hence I prefer not to buy even the most affordable ones, the bco'. This is because I am not interested in having a large collection of tools, but just using a lot what I already have. This is a personal opinion and doesn't have anything to do with excellent eyepieces out there.

The good and the bad of being a minimalist!

[jetstream]

No need to apologise Piero- they are cheap lol! and that is one of the beauties of them. I just wanted to emphasize the optical quality of these eyepieces. Orthos are definitely not for everyone and with the excellent widefields out there many don't see the need for them. BUT on nights of excellent seeing out they come or if we need to keep bright stars away from those cherished faint nebs...

To each their own is my motto.

[Dude_with_the_tube]

many might not see the need of the "cheap" orthos,despite some of the orthos are not that cheap and actually can cost even more then Ethos,but in my opinion,if you are after some critical detail on planetary or even a DSO object and dont need to see those extra degrees of FOV,nothing can beat a good old ortho and that has been conformed by many observers many times over.

As for the Pentax XO 5mm mentioned earlier.I do have one,it does deliver what it says on the tin and i have had some breath taking views with it,but as always there is a spoon of sand  in this case its the eye relief of the Pentax XO. 3.8mm for 5 mm ortho is really tight.If you can live with that,you will be rewarded with some cracking views and i would love to see Pentax XO as a proper series of orthos and not only in 2 focal length`s. Would be prepared to pay the high price they demand,but this isnt going to happen sadly.

If you really are a fan of orthos and have the cash to burn and can get your hands on Pentax XO,get it and you will love it.it is truly a magnificent eye piece.