View Full Version here: : Getting resolution parfocally

04-03-2007, 06:01 PM
Hello all,
I am deliberating as to which eyepieces to end up with. My main requirements are--1)parfocal 2)on axis resolution--3)of axis sharpness.
The main contenders are(drum roll) UO HD Orthos and Antaries elite plossls. The antaries are also sold by orion and celestron, about the only difference I can see is the price jumps. If price wasn't considered TAK's HiLe eyepieces would decorate my ep box. I am using mainly a 12" (white)light bridge and a 5" mak,soon to be 8" when it grows up. I personally like using off axis viewing with my dob instead of trying to keep the object centered. Which I feel efectively eliminates TMB planetary, might be wrong but I don't have all of them to use and short list. I recently got to sample a pentax XO 5mm, absolutely brilliant off axis and resolute oooo! But I want 4mm-12mm parfocal collection. Has anyone used the UO HD and elite plossls/ultrascopics back to back. They are both FMC, parfocal and the ultras offer slightly bigger FOV. Have I said to much. :help::eyepop:
Thanks Rod.

04-03-2007, 06:39 PM
Hi Rod!

:welcome: to the forum! Is parfocal really a requirement? The Pentax 5mm and 7mm (and 10mm) are brilliant eyepieces, with great on and off-axis sharpness.

04-03-2007, 06:48 PM
Um, yes but the pents are $445 and Tak's $215. I would just go Tak. I only wanted to spend $70-$125 as I would be okydoky with UO HD's and wanted feed back about the ultrascopics. I tend to find the obscure interesting. Big cheers for the welcome cheif.

05-03-2007, 06:10 AM
The UO HD's are excellent performers for the price. I've viewed through them on a number of occassions, but don't actually own any myself. I ended up getting the TMB Planetary 5mm and love it.

05-03-2007, 10:56 AM
I've read that they are the bee knee's, at the same time if your impressed with wide views you'll keep the TMB but if you like resolution UO HD are prefered, this is what I've been able to decipher from all text I've read. I live in good ship number 2---resolution wins. But that 3 for 2 is the carrot I can't resist.
Has anyone used the elite plossls do they hold up in good company. I had a look at the celestron version it had nice colour correction, In a perfect world I would have left with a full collection of MASUYAMAS not just the 2" diagonal I bought recently-My wallet was $2500+ short.(don't know were it went?) I'll keep using my 10mm long eye relief plossl with 1.5 barlow for star slitting, it works very well. But I would like a 7mm and 12/15mm parfocal pair mainly because of the cassigrain but it allows for quick comparison of magnifications (detail lost at high mag due to seeing conditions--but you still go there)
I want to make an educated decision and avoid collecting unused eyepieces. I have a pair of par focal UWA Meade 5000's 14mm and 4.7mm they work well for wide field and dso, planets cast up lots of internal reflections.

05-03-2007, 03:26 PM
I wasn't impressed with the 14mm Meade UWA s5000.. my s4000 version is far superior. Though I didn't use it on planets.

05-03-2007, 08:20 PM
The thing that interested me was TMB's look a lot like Tasco's and Babder offerings plus another that uses the same housing I didn't even bother remembering. Don't know the differences and I couldn't even speculate.
This sporadic weather leaves one with too much time to ponder and procrastinate. So far I have heavily modified my mak and baffled and blackened the elements in two ep's.
To much delight, these old plossls only suffer from quick assembly processes and still offer good views with a little TLC. Can't wait to be at the business end of my scope again.
I should say to, that every ones eyes are different and I don't intend on putting down any body else's choice or preference of ep, there all good on different objects.

Peter Bobroff
21-03-2007, 09:44 PM
It is relatively easy to bring a set of eyepieces to the same parfocal standard. Pick the one with the most in travel as your standard and measure how much out travel is required for each of the others.

Ask a lathe owning friend to make up the required spacing cylinders and glue them in place.

26-03-2007, 09:53 AM
Not having a friend with a lathe and being relatively poor (:sadeyes:), I found a cheap way that was good enough for me. My 9mm focussed quite differently to my 15mm (which was focusing close enough to the 2" 26mm - that's all my eyepieces :D). For fifty cents I bought a rubber O-ring from Clark Rubber which just slipped over the 9mm body. One o-ring was sufficient to get the 9mm focusing quite close to the 15mm.

26-03-2007, 08:20 PM
Thanks for your reply guys, what you have suggested is what I already do to a degree. The question was with out being painfully obvious, is that I intended starting a good quality eyepiece collection and figured to do this in a parfocal arrangement at the same time. Considering the use of these ep's will probably see their life span far exceed many a scope and be kept regardless well into the course of my hobby if chosen correctly. My mind is on par with two favorites one Takahashi LE's and University Optics HD range and one or two space walkers. I thought this thread fell into Siberia, it is good to know some one is out there to give you a tickle. Good advice- already doing it-what about those eyepieces?