Orthos. Nostalgia or useful?

[Richard N]

5 hours ago, Piero said:

Well, I'm probably the black sheep here

I doubt that you are. I suspect that there is as much lore as there is science in eyepiece selection. It will ultimately be a personal choice that is likely influenced by many factors - the measurable fidelity of the eyepiece being just one.

Edited July 20, 2023 by Richard N

[JAC51]

On 19/07/2023 at 12:21, Richard N said:

My orthos are here - thanks FLO. Slightly disappointed that the Starbase just comes in a plastic bag. Hope to get time for a daylight look through them later (and yes I do know that is vastly different to using them at night).

 

Update: both work nicely in daylight. the 10mm BCO seemed exceptionally clear. Looking forward to star testing.

Congratulations on the 10mm BCO I was given one by someone who did not like it.

I found it to be a really good eyepiece  and still amazing value for money. Contrast is very close to the Brandon’s I have but at a fraction of the cost.

Let us know how you get on with   Both your eyepieces 

[stormioV]

I'm also drawn to  Masuyama Genuine Abbe Orthoscopic Eyepieces

[Don Pensack]

What is the best planetary eyepiece?

The one in the focuser when seeing is perfect.

[Mr Spock]

🤣 That’s another one of those daft sayings. Like people who say the best camera is the one you have with you, then post a crappy phone pic to prove their point 😁

[bosun21]

I can’t get on with orthos at all. Whilst admittedly they are excellent planetary eyepieces I just don’t like having my eye pressed up against the small eyeglass. I feel far more relaxed and comfortable with having plenty of eye relief.

[Mr Spock]

My circle-t orthos are surprisingly easy to use. Even the 4mm is useable. However, I do, as I said above, like the long focal lengths with a x2.5 Powermate though. 

[John]

59 minutes ago, bosun21 said:

I can’t get on with orthos at all. Whilst admittedly they are excellent planetary eyepieces I just don’t like having my eye pressed up against the small eyeglass. I feel far more relaxed and comfortable with having plenty of eye relief.

As I've got older I've increasingly felt similarly. I still have one ortho but hardly ever use it these days. They are still great optically but I value observing comfort now more than I used to !

 

[Don Pensack]

On 20/07/2023 at 10:19, Mr Spock said:

🤣 That’s another one of those daft sayings. Like people who say the best camera is the one you have with you, then post a crappy phone pic to prove their point 😁

Perhaps you haven't used hundreds of different eyepieces, so I'll repeat what I often say: There are differences in eyepieces, and I certainly prefer some to others.

But, in 60 years of observing with 31 different scopes, never have I encountered a non-defective eyepiece (I've encountered only 3 defects) that did not allow me to see everything the aperture was capable of seeing when the Seeing conditions were perfect.

I've done scores of eyepiece comparisons, and a few have had sharper edge focus, or perfectly flat fields, or better correction of chromatic aberration, or superb contrast, or better behaved exit pupils, etc., etc.

But, on axis, in a cooled and well-collimated scope, the difference in image quality among eyepieces is pretty small--a fly on the rump of a horse.

 

Take a look at the on-axis measurements of Ernest Maratovich in Russia.  I think of the few hundred tested, maybe 1 was less than a perfect image on axis.

We eyepiece aficionados tend to make extremely minuscule differences into a good/bad dichotomy and tend to forget how incredibly important the atmosphere is.

Edited July 21, 2023 by Don Pensack

[JeremyS]

53 minutes ago, Don Pensack said:

But, in 60 years of observing with 31 different scopes, never have I encountered a non-defective eyepiece (I've encountered 3) that did not allow me to see everything the aperture was capable of seeing when the Seeing conditions were perfect.

 

Just checking I follow you Don, with the double negative. So you have only come across 3 eyepieces that were defect free. Which were they?

[Don Pensack]

10 minutes ago, JeremyS said:

Just checking I follow you Don, with the double negative. So you have only come across 3 eyepieces that were defect free. Which were they?

LOL.  I'll correct the wording.  Thanks.

[John]

I'd be interested to know which one eyepiece managed to mess up the perfect on axis image in Ernest's tests 😁

 

[Saganite]

On 20/07/2023 at 19:26, John said:

As I've got older I've increasingly felt similarly. I still have one ortho but hardly ever use it these days. They are still great optically but I value observing comfort now more than I used to !

 

 

My feelings exactly  and for the same reasons. I coveted my collection of UOVT eyepieces but they have all gone now. I do however  still have a pair of 18mm BGO's for binoviewing but the eye relief on them is still OK for my ageing eyeballs.

 

[Pixies]

A few times when I've been trying to split a tight double and not sure if I have, I'll try an ortho and often that sorts it out.

Putting the ortho in the focusser does feel like "rolling up one's sleeves".

[Don Pensack]

20 hours ago, John said:

I'd be interested to know which one eyepiece managed to mess up the perfect on axis image in Ernest's tests 😁

 

Celestron X-Cel 2.3mm

[Richard N]

Still getting to grips with the eye relief on the 6mm ortho.