The Edmund RKE look good.

 

Yeah, you'll have to get all learned up on bandpass interference filters, then explain it all to me lol. Just remember I've had brain damage ... so explain it slowly with no big words ROTFL.

You won't believe this but I've had to return the 7mm Fujiyama as it has a flaw. That's six deficient 7mm eyepieces I have had to return now! I'm starting to think I'm cursed.



The 7mm Sky-Watcher (Barsta), which is perfect and unflawed, was the cheapest of all of them and is definitely a keeper.

 

I've got the 12.5mm Fujiyama, and I think it's aces - I agree with the comments that you made about it. And yes, I don't actually really, really know, but I am also very, very sure from reading other people's posts at CN that there's just one company in Japan that makes all the orthos out there, so that this and all others are made at the one factory.

I got my 12.5mm ortho for my 5-inch Mak specifically to Barlow it and keep the nice 10mm eye relief. Alone it gives me 123x, and obviously 246x Barlowed. I have a Japanese-made Orion Ultrascopic 3-element Barlow that works beautifully with this EP. It is among my most used EPs. And yeah, I don't mind that it's 42 degrees, because I'm just using it for lunar and planetary anyway.

 

I'm a great fan of Abbe orthoscopics and I regularly use a 6mm Astro Hutech (and 2x TV Barlow) to get 300x on the Moon.

I'm not totally sure but they may all be from Ohi Optical Manufacturing Co., Ltd, Japan.

 

Your tales of woe with the 7mm EP's is jarring loose something I read somewhere regarding the number '7' being an unlucky number in some culture or another. Perhaps in Japan? Hmmm..... Anyone heard of this? If not - maybe we should start one?

I don't have any 7mm EP's in my collection, so I have no personal tales of confirmation to add - Yet! But something tells me that I've just set myself up to look for 7mm ortho's on the market. I do know that any other EP's I ever acquire will be of the orthoscopic-flavor. I'm especially interested to find an older (used) Edmund Scientific (USA) orthoscopic. They were the equivalent of the 'TeleVue®' back in the late 1960's and early 1970's as they were expensive 'back-in-the-day.' Around $35 each - which was well over $100 in today's money. Kellners were popular, as they were a step up from the more often found Ramsden - which worked but left loads to be desired. Us astronomy-people were a rare breed back then. Often thought to be the same folk who were into astrology who started conversations with - "What's your 'sign' my Brother?" STOP!

So, MTN - you found the RKE's to be interesting/good? I do too. I've been toying with the idea of getting one for years - but never 'pushed the envelope.' Yet. I've read many reports from folk about them, and all of them were good. I'm notsure quite what to make of these. They seem to have a narrow-ish FOV, and their design isn't particularly noteworthy, yet people hold them as being special. If you ever break down before me - I'd be fascinated by a review from you. I'll do likewise of course. Last I looked they were still a main offering of Edmund Scientific here in the USA. Me thinks me have a bit of chasing down details and some research ahead for me.

Currently I'm cloaked in heavy clouds and rain. Not as bad here as in the deep South - where flooding is causing people to call for rescue from homes & rooftops. But we've got our spotters out watching our local rivers and streams. The fire-department and national-guard were practicing manuevers across the street from me. Likely we'll be sending assistance South from the look of things. Vermont is always front & center for that. Such has delayed my plans to test my GSO 5X 3-element Barlow on a few EP's in my ST80. Ruud from across-the-pond in Holland suggested this thing is surprisingly good, so I got one. It could be a game-changer for my ST80 F/5. We shall see.....

Never play 'Trivial-Pursuit' with me...'
Have fun,

Dave

 

I think I must have been born under a bad sign or something. It is weird to get six borked eyepieces all of 7mm. I've since discovered that the 7mm X-Cel is renown for internal debris and many have been returned. The DeLites were a bit of a shock though. The Sky-Watcher/BST 7mm was a bit of a relief and at least that's fine, but the Fuiyama is an enigma.

7mm is good for me as it will give me 128.5x and 257x with a 2x Barlow on the Bazooka.

The Fujiyama has a defect I've never encountered before. It isn't obvious until you use it with a telescope, especially with a Barlow, and appears like a bright white doughnut in the centre of field. At first I thought I was seeing the obstruction but I can see it now even if the eyepiece is placed into just a diagonal, then the EP inserted into a Barlow and the diagonal is held up to a light source. It's interesting that no one else is distributing 7mm ortho's under any name from the same factory.



I'm not sure if I can get RKE's over here and I'm not too sure about import charges. They do look good though. I have that 15mm Celestron Kellner which I quite like, and several Sky-Watcher giveaway 10 & 25mm MA reversed Kellners, which aren't that bad. The 25's aren't bad bino pairs or used as finders. I can get Vernonscopes over here, unfortunately, lol. I mean, who needs hand built eyepieces made to Pentagon military specification standards? If Vernonscope did a 7mm I'd be sooooo tempted lol.

Anyway, hopefully, I'll get the Fujiyama replaced very soon.

 

I'm pretty sure it's the same thing. I think they claim a 16mm eye relief but I think it depends on how you calculate it. Distributors/manufacturers often pork pie about these measurements lol. I like mine a lot anyway.

 

It depends what you want the eyepiece for. To me, these Barsta/Sky-Watcher EP's are predominantly for lunar/planetary as they're 58° FOV. I've read they're also good for separating doubles and binaries. Although there's no reason you couldn't use them on anything really.

I'd say they'd be good for anything between a 1mm and 0.5mm exit pupil. The trick is probably to buy one that can be useful on its own and with a Barlow. Therefore maximising its use and potential.

The reason I suggested a 6mm was that on its own it will give you 100x. A nice low 'high' power which also gives you approximately a 1mm exit pupil. A 2x Barlow will give you 200x obviously (and about a 0.5mm exit pupil). You may even be able to push 250x with a 2.5x Barlow for lunar viewing.

However, a 5mm will give you 120x on its own and 240x with a Barlow. So I think you're right and a 5mm sounds like a good bet. 120x will be useful on its own for some DSO's and a good magnification for double stars. Jupiter can be good at 120x as well as it doesn't always respond to high magnification well. 241x is the theoretical maximum resolution for a 102mm scope (about 60x per inch) so 240x will be a great lunar magnification.

In fact, if my sums are right, a 5mm EP for your scope does more or less the same as a 7mm does for me on the Bazooka.

As for eye relief, I find I have to place my eye carefully sometimes near the eye lens or a slight amount of kidney beaning occurs. This could be peculiar to the 7mm though. Overall, I'm quite pleased with the SW UWA. I'm even more pleased it isn't bloody flawed! lol

 

I was kind of hoping to see Schroter's Valley near the Terminator tonight. Looks like pants clouds though.

 

Hey MTN -

Do you have any tales about these 5X 3-element GSO Barlows? And regards the RKE-line, I'll be looking into their availability over there. I've developed a hunch that may work out. I'll see. As for these Barlows, I normally would - and did - think them to be atrocious with that sort of magnification. But Ruud's opinion is good enough for me. He also sent me a good rating on the GSO 2" 2X Barlow, and it passed my testing with flying colour - although the 2" to 1.25" adapter it came with promptly jammed and died on-the-spot. As fortune would have it, I had another on hand to avert a return, even though it was of a unique design with a odd placement of the bolt to engage the compression-band. I have no idea why GSO did this.

Heavy clouds up here in Podunk. But clear enough earlier for the yearly air-show featuring the Thunderbirds, an Air Force precision flying-team. The fire-station across the street from me were on full alert all day, including some military outfits should one of their jets hit a house or something else unplanned.

'Ta,

Dave

 

I don't have any personal experience of GSO 3 element 5x Barlows Dave. I have a 2.5x 3 element GSO (TS Optics) Barlow, that may or may not be apochromatic, which I think is pretty good for a 'shorty'. If Ruud thinks they're good they should be OK. GSO do make some quality stuff, even their less expensive achromatic Barlows (often rebadged by Celestron and retailers like TS Optics) are pretty good.

I moved the Bazooka mount in daylight to view the Moon better later tonight. I had to polar align it with the digital compass on my Nexus tablet. I actually checked it against Polaris in the night when the clouds allowed it and it was virtually smack on.



In the end though it was getting late so I viewed a very low Moon for a while with the MightyMak 90mm instead.



Schroter's Valley looked good at around 53x but I think the Terminator shadows will be better tomorrow night. I may try the 9mm X-Cel with the TV x3 Barlow for 300x with the Bazooka.

Speaking of Thunderbirds ...

 

Omegon 90mm Maksutov? Interesting! That looks like a fun, little scope. I'm so very glad I already have my Maksutov. Otherwise I'd be likely typing up my order around now.....

That 'Thunderbirds' thing is truly horrible! I've added it to my inventory of evil things to toss at people! Of course I'm someone who was under a barrage of those things screaming over my head while I was trying to get some sleep here prior to hoping for more 'clear-skys' for tonight - no go. Tonight was a 'teaser' as when the Moon was rising nicely, with each degree of Moonrise° - the clouds would re-double their number and thickness. I'll put you on my 'Borat - List.' *

So you do have a 3-element GSO in 2.5? And it's 'pretty good?' That's good to know! Ruud has never steered me wrong. The 5X looks to be a quality build. It's obviously nicely designed & executed 'piece-o-glass.' And you're quite right about GSO and it's 'POG' these days. Everything I've gotten of their's lately - aside from one 2" to 1.25" adapter - has worked better than I'd expect from previous experiences with similar critters some years ago. It's always no-fun when I've gotten around to running tests on certain recent acquisitions, only to be kicked-to-the-curb by changing weather-patterns.

Guess I'll try some sleep. I hope I'm not awoken by a forgotten 'Farm-Implement Machine-War' across the way here tomorrow!

Guten Tag,

Dave

* 'Borat-List' - a truly horrible movie I built-up to a friend of mine in Australia until she 'caved' and bought it to screen for her friends & family. They were utterly horrified by her hideous taste in film, and she called me up on the phone to scream her lungs out at me for setting her up! Her friends and family were in the background - laughing hysterically! !

 

The MightyMak is also marketed as the Kasai Pico Stateside I believe.

http://www.kasai-trading.jp/pico8.html

My 2.5x GSO Barlow is sold and rebadged by TS Optics.



I can't fault the 2.5x Barlow, plus, it hasn't got an undercut. On the TS Optics website it's shown with an undercut but when I asked them about it they told me that their partner manufacturer (GSO) has stopped putting undercuts on a lot of their products (hurrah!).



If rave isn't your thing, how about some shoegazing genre? The Ladytron video was filmed at a 5000 year old stone circle near the Scottish village of Callanish. It is astronomically aligned, and although we can never really know why it was built, is a strong contender for an ancient observatory.

 

Very true, Ray. This "hobby" of ours is great for removing the cobwebs from any bank-account we may have that's dormant at any given time! And worth every dime and nickel we spend, most certainly.

Count your lucky stars <koff!> you haven't found Astro-Photography - yet!

Have Fun!

Dave