Choosing a Planetary eyepiece

[GazofCorra]

GB - No problem, non of us are perfect

John - As you say it was probably down to conditions and i agree, i have been outside for over 1 hour and it was absolutely terrible. Temp outside 12.2c and 64% Relative Humidity, looks fairly clear, but it was hopeless.

What i did manage to do was de-focus on a few bright stars and either side of the focal point the star looked like a donut and the more i de-focused the bigger the donut got but it was multiple equal fine rings with a hollow middle, boy you can tell i'm a newbie

[John]

What i did manage to do was de-focus on a few bright stars and either side of the focal point the star looked like a donut and the more i de-focused the bigger the donut got but it was multiple equal fine rings with a hollow middle, boy you can tell i'm a newbie

As long as the hollow middle is central to the donut either side of the focus point then you are OK

Mak's don't need much collimation attention I reckon.

[GazofCorra]

John, Yes it was smack bang in the middle either side of prime focus.

[russ]

John, Yes it was smack bang in the middle either side of prime focus.

Collimation is nailed

I'll be amazed if you ever have to touch it in the whole time you own it.

[neilmack]

Another vote for the Orthoscopic. Variously branded Baader Genuine Ortho, University Optics, KK, Circle T, and perhaps all coming from the same Japanse source. Relatively little eye relief, and field on the narrow side. But contrast, resolution, and light transmission are spot on.

[smudgeball]

Another vote for the Orthoscopic.

I'm glad to see that as I'll be purchasing a Baader 12.5 orthoscopic in a couple of weeks time.

Had thought about a Hyperion, but the ortho seems to get the nod from most planetary viewers.

With the Hyperion being a little more "general purpose" if that's not being too rude to Hyperion owners ??

Neil

[johninderby]

Another vote for the Orthoscopic. Variously branded Baader Genuine Ortho, University Optics, KK, Circle T, and perhaps all coming from the same Japanse source. Relatively little eye relief, and field on the narrow side. But contrast, resolution, and light transmission are spot on.

While many of the orthos do come from the same factory they do have different coatings. The Baader orthos do seem to have better coatings than the University Optics ones for instance.

John

[great_bear]

The Baader orthos do seem to have better coatings than the University Optics ones for instance.

Although this has been suspected, it's never been conclusively proved; whilst it's possible to find samples of UO-HDs that have demonstrably different coatings than BGOs, it's also possible to find samples that are completely identical.

With this in mind, I think it's more likely to be difference in batches over time rather than differences between brands.

[GazofCorra]

Collimation is nailed

I'll be amazed if you ever have to touch it in the whole time you own it.

Russ, I am so glad the collimation is spot on as i did not want to collimate a Mak and hopefully with some tender loving care it will never need it.

BTW - Alan at skies the limit is a really nice bloke and very helpful and he is now offering certain items on try before you buy, so you can try a certain eyepiece and if it is not to your liking you can send it back. I did ask if he had a 6" Tak refractor to loan me, lol.

I got my 4 & 6mm TMB planetary 2 EP's today and i must say that they look very well made, which surprised me a little as they are only £38. The box they come in is well made similar to my Televue EP box, also the eyecups rotate smoothly and the finish is excellent, i am very impressed.

[John]

I agree that the orthoscopics are excellent optically but I also feel that the tight eye relief can mean that they are not too comfortable to use for some people (like myself !) at least for extended periods (which is, IMHO, essential for detecting finer planetary details).

I have a theory that a relaxed eye is a perceptive eye so I would not dismiss eyepieces with longer eye relief - it might just be that you see a little more with them because of the comfort factor

That said, I've been giving orthos another chance lately, firstly in the form of the 4mm through 7mm University "volcano tops" and now with some Baader Genuine Orthos (5mm, 6mm and 7mm). It's a sort of experiment to see how I get on with them

[GazofCorra]

Good luck with the experiment and it would be nice to hear your conclusions when you have had time to get use to them.

[Revs]

BGO's every time IMO. I wear glasses, so it is a bit of a pain, but worth it. I've got a 12.5mm which Barlow's well and the 'hole' is big enough for me to manage pretty well (as long as I've not had too much beer )

I did a side by side comparison with the Nagler 12mm in my Dob looking at Saturn and much preferred the BGO, despite the smaller FOV and ER.

[smudgeball]

I take it the 12.5 ortho doesn't come with a rubber eyeshield ?

[Revs]

No, but saying that, I didn't miss it having one.

[smudgeball]

Thanks, not put off, just checking.

[John]

..I did a side by side comparison with the Nagler 12mm in my Dob looking at Saturn and much preferred the BGO, despite the smaller FOV and ER.

I found the 7mm BGO pretty much equal to a Type 6 Nagler 7mm when I compared them back to back a while ago over a number of nights. Last night the 6mm Ethos was showing Saturn's fainter moons just a little easier than the BGO 6mm but there was not much in it.

For their cost, the BGO's do offer really excellent optical performance if you can cope with the tight eye relief.

[Revs]

It was a clear night when I did the comparison, but seeing wasn't the best. I'm out again tonight imaging Saturn so I'll try again and report back, but this time with the Mak. But as you say, once you've taken cost in to consideration the ortho's really take some beating. The 12.5 is perfect for the Mak. I've not had chance to try the Nagler in the Mak so it'll be interesting

[GazofCorra]

Revs, i am looking forward to hearing your views on the BGO & Nagler, as i have the Nagler 13mm type 6.

BTW - The Nagler does not have an adjustable eye cup anyone find that strange, i gave mine a twist and the body unscrews from the 1.25" adaptor, oops.

I have a 2" Panaview and the eyecup rotates and adjusts your eye's distance from the lens which i find really nice.

[Revs]

Yeah the T4 has the adjustment. It's a notched slide as opposed to a twist and works very nicely. Good job too, because even with spec's on I can get too close. About 3 clicks does it I'm putting the Mak out to cool now and I'll report back in a few hours

[GazofCorra]

Revs, have you got the 14mm Type 4, i miss the adjustable cup on my Type 6 nagler.

[Revs]

12mm T4. Only had it a few days.

[Moonshane]

I think the BGO 12.5mm is a superb eyepiece for any target that will fit in the field.

[Revs]

I'm afraid the familiar high cloud has rolled in

[John]

Revs, have you got the 14mm Type 4, i miss the adjustable cup on my Type 6 nagler.

It shows how peoples feelings differ on eyepieces - many folks seem really to dislike the "Instajust" feature on the Nagler T4's, especially the earlier production runs where the friction was much less. I think T4's are the only Tele Vue eyepieces with adjustable eye cups.

Personally the T4 approach didn't bother me although I think the UWAN / Nirvana "twist up" version is a better implementation of an adjustable eyecup.

The Nagler T6's eyecup is as it is because eye placement is more critical on the T6's as they have less eye relief than the T4's. One thing you can be sure of with Tele Vue is, like it or not, the features are designed they way they are for a reason. That said I would personally liked to have seen a more flexible rubber eyecup on the T6's so it could be folded down if you preferred that.

[Revs]

I find it spot on. I was using it with the Dob and I found that it never slipped yet was adjustable without disturbing the scope. Really lovely bit of kit. The fov is astounding and the contrast superb. A real treat on clusters. But I still found the BGO sharper on Saturn