Meet my new Pentax family

[F15Rules]

I've been a long time fan of all things Pentax. I like the fact that they make superb products, and yet market many of them in a very low key way - almost only by word of mouth and dealer recommendations in the case of Astro equipment.

I owned a couple of their early achromats, the Pentax J80 and J60, and the J80 gave me some of the very best stellar images I've ever seen, through ANY scope. Another one I stupidly let go some years back (story of my life...).

Over the years I have tried most of the mainstream brands of eyepiece, with the exception of most of the uber-wides apart from a couple of Naglers, which I really liked but which were very tight on eye relief (I don't wear glasses to observe, but I do have long eyelashes, which can play havoc on the glass especially on cold nights). 

My own "sweet spot" for viewing comfort is around 60-70 degrees fov and 15-20mm of eye relief. My first experience of Pentax eyepieces were the XF range, which sadly only come in 8.5mm and 12mm sizes. I've owned both and was very impressed by both, in particular the 8.5mm which is just a superb eyepiece for the money (under £100 these days, new).

Earlier this year, I took the plunge on the Pentax SMC Zoom 8-24mm, having admired them from afar for a very long time, but balking at the (then) £405 retail price on FLO etc. I also had some reservations, despite good reviews online, having owned the "cheap" XF zoom, which I had the misfortune to own and found to be truly awful -  a real dunce of an eyepiece, with huge globs of CA in daylight and nighttime use - although, to be fair, I have seen good reviews of the XF zoom for solar observing. Odd.

Anyway, I did order the SMC Zoom (sometimes called the XL or XW zoom, as it was launched when the XLs were the top of the range Pentax eyepieces, followed by the XWs which replaced the XLs), and I have to say that although I haven't used it nearly as much yet as I would like, it is superb optically, and it's also superbly built. In my Vixen ED 103mm F7.7 refractor it only gives c x100 maximum at 8mm, but with a lovely 60 degree field. And, with the bottom of my APM x2.7 barlow, which gives when used solo a x1.5 magnification, that jumps to x150, which is often high enough in our turbulent skies. And, on all too rare very steady, clear nights, the full x2.7 of the APM gives x268, plenty of magnification for anything my Vixen can show well. I'm delighted with it. Mention also has to be made of the build of this eyepiece - it's BIG, but not too big. It is lighter than my late lamented, and much loved Meade 4000 14mm UWA, but not much heavier than most of the XL/XW range (although taller than some). 

So, having had a first, and very positive taste of a premium Pentax eyepiece, I started for the first time, to seriously consider some of the fixed length versions, with the aim of simplifying my arsenal, and spending more time viewing than changing out eyepieces. While having these thoughts, a used, but in good condition Pentax XL 5.2mm came up for sale, and after a few days was reduced to the point I could not resist. At 5.2mm it would slot in nicely above the 8mm max (without barlow) of the Zoom. So I bought it, and have to say I have been delighted with it. It gives x152 in the Vixen, a nice moderate-high power, and with a 65 degree field, just great. 

Originally I had thought I might stick at that. Then I made the mistake of watching ebay, and I came across an XL10.5 mm, on ebay Italy, and described (through Google translate) as "new old stock", complete with original packaging and all papers. It seemed too good to be true at the price advertised for Buy it now, and I watched it for 3  or 4 days, fully expecting it to be snapped up. Amazingly, it wasn't and I could resist no longer and pressed the button, not a little nervously! 

Well, it arrived this week, after taking 15 days to get across the channel via France no doubt, (you've got to love the Italian sense of urgency and "express post"), and I opened up the package with not a little apprehension. I needn't have worried though, it was indeed new old stock! Amazing, when you think that it must be 10-12 years since the XLs were discontinued. The plastic inner transparent square storage case was a little yellowed, as if it had sat in the shop window for a while, but apart from a little dust, easily removed with care and the wonderful Baader Wonder Fluid, the lens is now pristine again - and the views are all I could hope, in daytime (no night testing yet). 

All this time, I was reading up all I could on the XL versus XW debate. Most of the reviews I found said that there was very very little in it, apart from the extra 5 degrees of view for the XW, and some observers in the USA felt the XWs had very slightly improved contrast. We shall see. 

I had placed a wanted ad on SGL for an XL 10.5mm and had an offer from one seller for an XL, but then had another offer (having just bought the 10.5 online) for a 10mm XW at a cheaper price than the XL was offered at! So I got into correspondence with the seller of the XW and found that he had most of the range (apart from the 30mm 2", which he was offered an amazing £650 for!!), and he was looking to sell them all. So, after much deliberating and trying to figure out what I could sell to help finance the new purchases, I bought the 14mm and 20mm XWs via SGL.  I have to say that they both arrived looking totally as new - if I had bought these from FLO as new, I would not have suspected that they were used units! Amazing!

I felt that these would give a really nice distribution of magnifications, at 5.2, 10.5, 14 and 20mm, supplemented nicely by ES 24mm and 34 68 degree low power units, the APM barlow, and of course my trusty SMC zoom, which is just great for dialling in the best magnification on a given night. I often don't actually know at what exact magnification I am observing with the zoom or zoom/barlow combination, I just stop at the magnification that gives me the best view on a given night. 

Apart from the smaller field of view from about 12mm down to 24mm, the Zoom acquits itself really well against the XLs and XWs in daytime testing. I haven't tried them at night yet. 

All in all, I feel really elated to have put this little lot together, and am really, truly, going to try to stick with these to give them a good long field testing as my possible permanent eyepiece line-up (no chortling please!).

Hope you like the pics and thanks for bearing with my schoolboy enthusiasm.

Dave

[dweller25]

That's a very nice collection

[DRT]

Very nice indeed, Dave. I hope you will all be very happy together

[philj]

Very nice Dave

[Moonshane]

Lovely Dave. I have not tried bigger pentax but never got on with the cheaper zoom for reasons you mentioned and the xf 8.5 does not compete with my Delites. I think yours are a class or two above ones I have tried.

[nightfisher]

Dave, i dont usually suffer jealousy but at this moment i am, that is a superb set of ep`s and hope to hear how they perform 

[Pig]

I kind of got bitten by the Pentax bug also.... only I have the Leica zoom instead and Baader VIPBarlow 

 

[Saganite]

That is a beautiful sight !!

[John]

Very nice set Dave

I'm a great fan of Pentax gear myself - I have the 4 shorter length XW's.

 

[Highburymark]

Lovely - and clearly much loved - set of eyepieces Dave. The XLs look very nice indeed.

[YKSE]

A very nice set, Dave

It's not that often hat you post a picture of your set, I can really feel your enjoyment

[alan potts]

Congratulations Dave!!! It is the very first time I have ever seen the 5.2mm XL. In my view though, I have by no means had all of the them but if you are content with 70 degrees of field then they are difficult to better at the short end and every bit as good if not a tad better in some areas than Delos. I have always thought though the 14mm Delos was better and that is where my involvement with them stopped. Many thanks for the photos and very nice report!

Alan

[Transit]

On 7/05/2016 at 04:49, F15Rules said:

I've been a long time fan of all things Pentax. I like the fact that they make superb products, and yet market many of them in a very low key way - almost only by word of mouth and dealer recommendations in the case of Astro equipment. 

I am also the Pentax fan but arrive here from the photo side of the family

 have just bought a Pentax O-GPS1, the gaget will physically guide my DSLR sensor for up to 5 mins.

Their marketing is improving now Ricoh is in charge

cheers

Pete in NZ

 

[michael.h.f.wilkinson]

Superb set. I have three XWs (5, 7, and 10mm), and absolutely love them. I am seriously tempted to replace my WO 7.5-22.5 zoom with the SMC.

[Linda]

Good for you. I understand your enthusiasm for them.

I waited for too long for my chance... There was a used 10mm Pentax eyepiece for sale in my country, but at 2+ hours driving in one direction. I was sceptic to buy it unseen, because you don't know the quality. The seller didn't trust mail transport and I found it too far driving for just collecting an eyepiece. So I wanted to wait until I would ever drive in that direction and then buy it personally. It was for sale for 3/4 of a year or so. But I checked right now and now it is sold. 

[F15Rules]

Well, guys, I feel I need to update this original post..

My new "Pentax Family" has been changed...

I still have the 5.2mm and 10.5mm XL versions. I absolutely love this pair, they are in great condition, (one of them, the 10.5mm I found in Italy as a "new old stock" bargain, so it is literally like new). I could not detect any difference in optical quality between the XLs and the XWs.  The XLs have 65 degree field, the XWs 70 degrees, not a deal breaker for me. The claimed contrast  improvements I have read about on the XWs would be subtle, and at this time of year it just doesn't get dark enough to detect such small differences. I can say that the 5.2mmXL  in my Vixen F7.7 apo doublet gives very dark backgrounds, at a magnification of about x150 and I am well pleased with it.

The XW's were a different story. I was really disappointed with the 14mm. It had a lot of field curvature and kidney beaning, no matter what eyecup setting I used, and I could not comfortably use it for extended periods. I was really surprised at this. I sold it (it was in mint condition) readily enough, and I have replaced it with a new Baader Morpheus 14mm 76 degree field. I got this new for the price of a used XW14mm and although it's early days yet (due to the rubbish skies this summer), I am very pleased with it. I had a first good view of Mizar 2 nights ago and it was superb, great contrast, just as good as the XW, and sharp to over 90% of the field - bear in mind that the ep has a 76 deg fov vs the 70 of the XW, that means I was getting very sharp images across very nearly a 70 deg field. The field stop is pretty sharp, not quite XW sharp, but sharper than reviews had let me to believe. I do think the holster thingy is a gimmick and won't use it, and the eyecup is rather flimsy, although it has stayed in place ok, but apart from that, this is a wonderful eyepiece.

I also sold the XW20mm. This did not have kidney beaning, but the field curvature was much worse than I thought and I just could not get sharp to the edge views with it without refocusing the scope - in fact I'd say it was only really sharp to about 63 degrees or so. By contrast (sorry for the pun), my ES 24mm 68 is sharp almost to the very edge, has less field curvature in my Vixen, and is more comfortable to use, so I have kept that one  - for the price I paid it is my best bang per buck eyepiece. 

I also have the ES34mm 68 "hand grenade", a truly wonderful wide field low power ep, and that isn't going anywhere!

I sold the Pentax Zoom just because I couldn't justify keeping a £300 plus eyepiece for only occasional use, when the above selection works so well for me. It was a superbly built eyepiece, and lovely to use, but the narrow field of view at below c 16mm setting was a bit of a let down versus the XL/XW fixed length units.

I can also barlow the Pentax XLs at x1.5 and x2.7 with my APM barlow, so I can get up to x400 or so if we ever get a suitably good night - not holding my breath on that, although daytime views at x250+ hold up very well indeed.

I think my overall conclusion is that XW eps are wonderfully built, but they are best at shorter focal lengths. I have a friend who has 5, 7 and 10mm examples and he can only praise them in every respect. At the longer lengths. and based only on my experience, the Morpheus and ES competitors are darned near as good optically, better in field curvature and far better value. Just my opinion. But I am happy at 65-75 degree fields of view, they are just right for me 

Dave

[michael.h.f.wilkinson]

I have never looked through the XW14 or XW20, but I have (two) MaxVision 24mm 68 deg EPs, which have the same optics (it is said) as the ES 24mm 68 deg. I can only say the MV 24mm is excellent, and only in very fast scopes (like Olly's F/4.1 20" "Sir Isaac") does it show any problems (flocks of seagulls at the edges). The 22 Nagler fared fine, so it wasn't coma that was causing trouble. Having said that, the 24mm 68 deg is claimed to be good down to F/5, so the problems at F/4 are no surprise. A set-up consisting of ES 68deg, the odd Morpheus, and the XWs/XLs at the top end sounds absolutely great, especially if you do not have a fast Dob.

[YKSE]

Dave, thanks for the update, very informative as usual.

I understand the sky condition haven't been very favorite for more extensive comparison for Pentax zoom. Is there anything more you've observed? such as ER? lateral colour? possible vignetting in some focal length? etc

[F15Rules]

Hi Yong,

Regarding the Pentax Zoom, I'd say the following:

Plus:

Build quality, optical quality, eye relief (I would estimate similar to the fixed length Pentax EPs),  sharp field stop across range, sharp field at all magnifications. I also really liked the calibration markings on the zoom body showing both magnification (when used in a spotting scope) and focal length in mm for when used in an Astro scope.

Negatives:

Field of view..at 8mm setting its fine, 60/degrees. Below c16mm setting I estimate it at under 50 degrees, down to c38/degrees at 24mm. It never felt like a "tunnel" though.

Stiff zoom action when new: because this zoom has O rings to improve a water resistance, it must be very firmly held in the focuser, otherwise the whole eyepiece can turn. I found the best way to do this is to use a Baader clicklock. This really grips the EP body tightly and allows the zoom adjustment to operate smoothly. Used in this way its a great, smooth action.

Like all Pentax kit its a lovely thing to hold. Hope that helps

Dave

[Louis D]

I've owned the 5.2mm and 14mm Pentax XLs for almost 20 years now.  I still love the 5.2mm, but the 14mm now requires refocusing the edge because I've lost focusing accommodation with age.  I never noticed it until I needed bifocals.  I, too, am looking to replace it with either the Delos or Morpheus.  I will say that it has no kidneybeaning at all.  You just look in the eye lens, and there's the image with no fussiness about eye placement.  I guess Pentax screwed that up with the 14mm XW.

I have found myself enjoying the 12mm Nagler T4 which is flat and sharp to the edge with a coma corrector in a newt or field flattener in a refractor, and it gives a larger true field than the 14mm XL, but with tighter eye relief.  Used, they're the same price as the Morpheus new here in the states.  If you don't wear glasses to observe, check out the entire Nagler T4 line if you like wide fields with comfortable eye relief.  They're just usable with eyeglasses, but the view gets hard to hold.

I also have the 17mm T4 and find it to be excellent as well.  At 22mm, I'm quite happy with the Astro Tech AF70 which is sharp out to 95% of the field, has a nice flat field, and about 18 to 20mm of eye relief with no eye placement fussiness.  It's also available as the Olivon, Celestron Ultima LX, and various house brands.  The 13mm and 17mm versions are no where near as nice as the 22mm for correction, but good enough for outreach events.