LVW v Circle T Ortho - moon test

[Mr Spock]

A few nights ago I had the luxury of some good seeing conditions. It gave me a chance to test out my iOptron 150mm Mak on the moon. The eyepieces I used were:

Circle T Orthoscopic 9mm - x200
Vixen LVW 8mm - x225
Circle T Orthoscopic 7mm - x257

I concentrated my efforts on Montes Jura as they were right on the terminator. There was a thin bright link, which was finely etched, catching my interest, along with some humps and bumps.

Having tried all three eyepieces I can say that, while the 65° view of the LVW was appreciated, the 40°+ view of the orthos didn't really bother me; I know some people feel 'shut in' by them. They were also a little sharper, with the highlights being brighter. Gentle contrasts on the mare were also easier to pick out. The 8mm LVW is one of the better eyepieces out there, certainly better than a lot I've tried. On this occasion though the orthos were distinctly 'crisper' and gave the more enjoyable views.

Mars was a bit fuzzy by the time I got to it. The 7mm ortho was still able to pick out some complex surface detail though. It's a shame my scope and mount weren't operational to see it at its best.

I won't ever part with my LVW collection - they are too good - but, the small size and clean image quality of these orthos is very pleasing. Once I find a 5mm I'll be very satisfied.

[NGC 1502]

That’s very interesting. Although the only LVW I now possess is the wonderful 22mm, I always regarded the whole range as excellent, which of course they undoubtedly are.

One of my scopes is a 6” f3.8 and the 22 LVW holds its sharpness amazingly well towards the edges making a coma corrector unnecessary.  Not pin sharp at the edges but excellent, walks all over a 19mm Panoptic in that regard. The Pan is of course a lovely EP in many ways.

There’s a 13mm LVW currently available at a well known UK retailer of used kit.  It may look expensive but well worth it in my opinion.

Ed.

[Mr Spock]

I have the 42, 22, 17, 13 and 8. They are all excellent.

[michael.h.f.wilkinson]

I only have the LVW 42 which is great, and a 25 mm Ortho which is wonderful in solar H-alpha, and I used to have a 5mm circle T, which was very sharp indeed, but drove me nuts with its small eye relief. I will stick with SLVs or XWs for the shorter focal lengths

[Padtwo]

Thank you for this post. As a beginner I have managed to pick up a 9mm circle T eye piece as a first foray into orthos which was my main reason for reading the post. Just got to practice with it as I've got used to eye cups and it feels a bit strange without one!

However I've now realised I was also looking at the Montes Jura and saw the jewelled handle effect as well. Off to read up on the geography of the moon some more....

[NGC 1502]

2 hours ago, Mr Spock said:

I have the 42, 22, 17, 13 and 8. They are all excellent.

Sorry cannot agree.    They are superb 😁 hope you get the 5 previously mentioned.

Ed.

[Mr Spock]

5 hours ago, michael.h.f.wilkinson said:

I only have the LVW 42 which is great, and a 25 mm Ortho which is wonderful in solar H-alpha, and I used to have a 5mm circle T, which was very sharp indeed, but drove me nuts with its small eye relief. I will stick with SLVs or XWs for the shorter focal lengths

I used to have a 4mm NLV which was bitingly sharp. I had my best views of Mars with that and a 250mm f4.7 Newt a few years ago.

[michael.h.f.wilkinson]

4 minutes ago, Mr Spock said:

I used to have a 4mm NLV which was bitingly sharp. I had my best views of Mars with that and a 250mm f4.7 Newt a few years ago.

I can well imagine. I have the 5 mm SLV, and is superb on planets. It is every bit as sharp as the Pentax XW 5 mm, all it lacks is the FOV of the XW (but then you pay for that). I use the SLVs (5, 9, and 15 mm) as my travel set, along with a 24mm 68 deg MaxVision. Works really nicely with the 80mm F/6 as travel scope.

[jetstream]

On 27/01/2021 at 12:58, Mr Spock said:

They were also a little sharper, with the highlights being brighter

Glad you like the Circle T's, I love mine as well and have a mostly complete set, with many doubles.Missing the 25mm, if they made them.

[Mr Spock]

17 minutes ago, jetstream said:

Missing the 25mm, if they made them.

I have a 25mm  Lovely image quality.

[John]

When I tested the 6mm Vixen SLV I found that it matched the Baader Genuine Ortho 6mm in every way each time I used the two of them. The SLV was more comfortable to use of course. The Baader GO 6mm was a touch better than the Circle-T 6mm ortho that I had at that time too although I do prefer the ergonomics of the "volcano" tops in the shorter focal lengths. I have a flat top 4mm HD Ortho at the moment (Fujiyama) and while sharp as a knife it's not an eyepiece that I enjoy using. Finding and holding that tiny eye lens in the dark needs a steady head and patience.

I tried a couple of the HD orthos (Astro Hutech and Fujiyama) in 25mm and didn't like them much I'm afraid. Optically fine but the eye relief / eyepiece shape ergonomics just did not work for me - too much "eye hovering" involved.

 

 

Edited January 29, 2021 by John

[Mr Spock]

I don't think I could manage a 4mm Ortho, the eye relief is just too tight. 

I did some measurements on the 9mm and 7mm orthos with a Meade 140 apo barlow nosepiece screwed in directly to the eyepieces. I got 5.77mm and 4mm respectively.  Not bad at all if I need high powers. 5.77mm gives x312; the 4mm gives x450 which is a bit much.

[jetstream]

There were a couple of reasons I bought 2 of each Circle T- one for binoviewing and the other for deep sky very faint galaxy viewing. After buying a super 7mm KK ortho I bought a 5mm KK Fuji- and while good its not excellent. So after testing and sorting through my Circle T's I have some that equal the 7mm KKs performance on faint galaxies. These high transmission copies also happen to be very sharp lunar eyepieces. I'm glad I have them all!

[RT65CB-SWL]

I have the 6 & 12.5mm Circle-T Ortho's (images below) and are my most used lunar e/p's.

 

...and this is my 0.965" / 6mm Ortho e/p (shown with a 1.25" adapter) was my first upgrade when I used to own a Prinz Astral 550. 

 

[Pixies]

I have a 4mm Circle-T ortho, which I normally only use for star tests. However, last week during an evening of particularly good seeing, I used it to split the tighter pair of Tegmine.

My other Circle-T orthos are 6mm and 7mm (University Optics). I also have the 8m Vixen LVW. The  Vixen has a great advantage with it's wider FPV, especially with my dob. But the 7mm Ortho just pips it for sharpness.

[Mr Spock]

26 minutes ago, Pixies said:

The  Vixen has a great advantage with it's wider FPV, especially with my dob. But the 7mm Ortho just pips it for sharpness.

Exactly what I found. I'm not bothered about the FOV as my scope is driven.

[A McEwan]

Not at all surprising! A lot of us have multiple Orthoscopics specifically for lunar and planetary views. Why? Because they're so good at it!

Really really dedicated planetary perfectionists use monocentrics, but I've never tried one and 30 degree afov... nah, I'm quite happy with my more-versatile Ortho's!  

Ant

[John]

1 hour ago, A McEwan said:

Not at all surprising! A lot of us have multiple Orthoscopics specifically for lunar and planetary views. Why? Because they're so good at it!

Really really dedicated planetary perfectionists use monocentrics, but I've never tried one and 30 degree afov... nah, I'm quite happy with my more-versatile Ortho's!  

Ant

I did own a TMB Supermonocentric 5mm for a while. Probably the best eyepiece in terms of pure optical quality that I have ever used. But very hard work with my undriven alt-azimuth mounts !

I'm not really that dedicated or that much of a perfectionist

Today I could probably get about 3x what I sold it for back then !.