Ex Sc 4.7mm UWA and Pentax 5mm XW

[alan potts]

Explore Scientific 4.7mm UWA and Pentax’s  5mm XW.

Firstly let’s hope this lays to rest any ugly rumours that I only write about Tele-Vue eyepieces, well at least I managed to get the Company name in the review once and will probably try again later.

Explore Scientific 4.7mm UWA.

This is a nice looking eyepiece which comes in a very nice box that doubles as a star chart, I would not go so far as to say that it is over the top but companies using JOC do seem to spend on boxes. Meade boxes were made so you could almost throw them from the top of buildings and now we have this very impressive folding affair and I have to say the nicest looking I have seen so far. The only problem with this is all of mine are in a black bin liner in the barn out of the way but I am sure some people keep them on shelves in their boxes.

The packing is more than adequate and the eyepiece comes with caps of course which look very much in the same vein as Meade’s caps but with a different logo. Many believe that Explore and Meade’s older 5000 series were the same glass in different trousers; personally I am not so sure.

The eyepiece is on sale in Europe for 119 Euros which I believe is about 100 quid, so very reasonable from my point of view and much cheaper than the eyepiece I have paired it against, though the cost on the British marketplace I understand it somewhat higher, which I will not go into. The Argos scales in the kitchen tell me it weighs 220 grams and the recorded eye-relief is 13mm, so may well be too tight for anyone wearing glasses. It was interesting that in use I found the reported eye-relief much tighter than claimed, this could be due to the eye lens sitting in a recess, I found the relief no better than 10mm. The whole thing looks and feels well put together but I notice a different approach to the machining of the barrel, most eyepieces I have ever seen are either straight sided or have an undercutting or recess in them, this seems to be slightly conical, may be interesting to see how it performs.

The other rather interesting feature of these eyepieces is the Argon purging and they are waterproof, so no problem putting them on a quick wash and spin cycle. I am not sure if there are any advantaged to be had from these two features but I guess the fact that you can wash it is a plus, though I am entirely sure I would want to try.

Pentax XW 5mm

This is one of the shorter eyepieces from, now Pentax’s only range of eyepieces and even that has been cut down from a couple of years ago. The 5mm XW comes in a simple sturdy box bearing the Pentax name with lots of fitted padding on the inside holding a bolt case, in which  the eyepiece is housed. I don’t know of another company that offers a bolt case with the eyepiece, the way I use my selection it is somewhat unnecessary but it is a nice little addition that just puts the icing on the cake.

The XW weighs in at about 400 grams, so more of less twice the weight of the Explore eyepiece, the eye-relief is 20mm which I believe is the same for the whole range and would be of interest to any one with glasses that had to use them whilst observing. Pentax favour the twist up type of eye-guard which has a very solid and profession feel about it, many prefer the Pentax type of system, one which Meade used on the UWA range but Explore went for the flip up rubber, personally I don’t really care which I use as long as it works. The barrel of the Pentax is the straight sided affair with a small recess cut out at the very top which I do not believe comes into play with my diagonals as I feel the compression bands are thicker, all in all the Pentax looks and feels like a quality eyepiece.

Telescopes.

This focal length range in eyepieces is mainly going to be used for planetary work, the tighter double stars, opening out globular clusters and hunting down faint and fuzzy galaxies.

I will be using my 115mm APO where the magnification will be X161 for the Pentax and X171 for the Explore Scientific, I do not consider a difference of X10 to significant I n this matter.

Slightly longer at 1 meter is the Sky-Watcher 190mm Mak/Newtonian where the powers are a little higher at X200 and X212 respectively, again not significantly different.

Targets.

Saturn

Messier 57

Messier 3

Porrima

Antares

Vega

The Moon

Messier 5

First light to the Explore came in the 115mm or 4 ½ inch in old money, F 7 APO refractor which even though it has taken a fall is still a fabulous telescope, just a little dent in the dew shield to show for its first and hopefully only case of concrete rash.

The Moon.

Now I rather like the Moon when viewed with around X160 and with this scope it is well possible to view the whole Moon surface at once with the right focal length of Ethos eyepiece but for this exercise we will have to be happy with most of the Moon’s surface. The Moon was at first quarter and I used the same two nights as on one of the other reviews, but just took a rest between to allow my eyes to fully relax once more. As said before condition were not text book but reasonable and at this power less of a problem.

Taking in different craters made a change for me, starting out with Aristillus, Autolycus and Theaetetus, all of which sit to the one side of the Mare Imbrium. At 15 miles across Theaetetus was the smallest and clean and sharp in the 4.7mm eyepiece and I could not detect any really obvious softness at the extreme edge though I could see it was not exactly the same as the craters on axis. Looking at the limb of the Moon at the very edge of field did reveal a little colour which looked like slight chromatic aberration which got worse at the very extreme edge. I did not consider this as awful and it was not apparent to me when the view was filled with Moon surface. It should always be remembered that I am going out of my way to find faults though Dobsonian users will allow the entire Moon to drift though the field of view before nudging the scope as they call it. People that have driven scopes will most likely not see such things as easily, I for one most certainly did not until I started writing these reports.

There was also a little but less chromatic aberration visible with the Pentax as well so both suffer from this fault to varying degrees, with the XW the aberration was at the very last 5% of the field, but it is worth noting the field is somewhat smaller than the Explore 4.7mm. I just felt the 5mm XW had a bit more bite about it in general with a better contrast and a little sharper at the edges, though on axis I can’t say I could see much difference. It was clear that this is a very fine eyepiece but being pushed hard by the much cheaper Scientific 4.7mm.

The Crab Nebula on the Moon, never.

This is from an observation that I made last night, I was looking at the Moon which was rather low and in great danger of being hidden by a walnut tree so a placed my scope as far down the garden as I could to allow me the most time. It is not just a case of getting the scope on an object, you also have to consider the heat dissipation from the surrounds ruining the view. Even though no one lives to the west of me until you maybe reach Italy, the land and trees still have to cool down, though it had not been so hot today. Anyway laptop and scope I was looking at a what was a Sea but could not find out the name of it from the map, then to my surprise up came the Messier 1, the Crab Nebula on the Moon, then Messier 3, a globular cluster as well. These were very small craters in this Sea of unknown name and difficult as it was in a sky that would never pass as dark, I could see them with the Pentax XW though visibility was drifting in and out with the tide of heat rising. I could also see them with the 4.7mm but only on axis and close to it; the fact that the Explore Scientific was showing more sky was not helping its case as it was having an effect on the contrast and I do not believe the scopes goto system can move the Moon.     

Vega

I picked Vega again because it is so high in the sky and in doing so almost definitely ruled out the chance of seeing atmospheric aberrations which you can pick up by selection of a bright star that is below about 40 degrees above the horizon; Vega was close to the zenith so could not get higher.

Viewing a bright star at X160ish is a tough test on any eyepiece and becomes harder when you place the start at the very edge of field. On axis the Pentax I though had the edge in overall control of the airy disc and at the edges the Pentax was a good deal better. There was a fair amount of lateral colour that could be seen in the Explore 4.7mm that got worse the further out you moved it, there could also have been a little astigmatism mixed in as well. It was interesting to note that while I could see an amount of faults with the bright Vega not at time could I see the same faults in any of the less bright stars that were in field periodically.  . The Pentax was clearly better here and I could only see the slightest amount lateral colour towards the edge covering the last 10% or so. Both eyepieces handled on axis light scatter very well though for me the XW was again in the driving seat giving a more exact point of light.

Messier 5

I sort of always forget about this fine globular and I don’t really know why, it’s fairly large at 17 arc minutes and bright too, given a magnitude of 5.8 though I can’t say I have ever seen it with the naked eye, one to try for that it for sure. I had to drop the eyepiece power to something more reasonable as the goto didn't find the cluster but in my trusty 35mm Panoptic there it was.

The Pentax framed it very nicely and I spent a good while just looking and taking in the countless stars wondering was there anyone on a planet around one of them, telling my Son he suggested giving them a wave or a little later flashing a torch and offered to run and get one.

No doubt the XW gave a beautiful clean and sharp view that would be difficult to better.

The Explore with its wider field also gave a stunning rendition of the globular but it just did not seem to have the same impact on me, nothing wrong with sharpness and the rest, just not as good. Feeling I was being unfair I moved elsewhere and came back to it and viewed the cluster with the two eyepieces the other way around, using the 4.7mm first and dwelling on it.

Nothing much wrong with the view, I could not see any edge problems of any type but when I put the Pentax in it just had more, it went to eleven.

I would like to point out this was based on only one nights observations, I normally like to view targets at least twice but weather has not been my best friend, this year that has gone to twelve.

Porrima.

A reasonably tight and bright double in Virgo and most of the time no test of a 4.5 inch scope; sometimes it can be tricky when it is getting low or rising.

Both eyepieces split the stars with ease on axis and a clear split was seen off axis though very near to the edge Porrima was bright enough for lateral colour to kick in and spoil the show in the 4.7mm UWA.

I had been formulating the opinion for a while that this Explore Scientific was not as good as my Meade 4.7mm series 5000 which after all cost a lot more, though I was only going on memories from about 18 months beforehand and that is not the best test criteria, it is valuable to have both under the same conditions. Still it really makes me want to lay my hands on a set of each and really have a good look for myself.

Again the Pentax was winner, for want of a better expression, but if you were to ignore the very edge performance then there was not a great deal in it and also consider the XW 5mm is over  3 times the cost.

 (Cost based on price available to me here, ExSc 119 Euros XW 5mm 369 Euros).

Sky-Watcher 190mm Maksutov/Newtonian F 5.26.

Saturn,

When I started this Saturn was very near to opposition and well placed in my sky and from memory a bit brighter than it appeared last night. Now it is almost ‘treed out’ as the great Sir Patrick would have said as soon as it is dark enough to view and will not be observable for a great deal longer for me.

I think the 4.7mm UWA was up against it from the start here as many consider the Pentax XW 5mm as an orthoscopic eyepiece with 20 mm of eye relief and as such made for planetary viewing. The image through the Explore was very good indeed and on the nights ( 4 of them ) viewed was bang on the money with the magnification though the seeing would have taken a bit more on two of the nights. The Cassini division was clear to see and was no better in the Pentax though if anything the XW was a light brighter and maybe a little whiter to, the transmission of the Pentax has always been legendary and I believe solely because of this the 4 moons on display were more in your face. It again was only once we moved things around that faults could be picked up, at the very edge I could not see Cassini in the Explore Scientific where as in the Pentax I could, this is of value to the Dob Mob though no doubt they all use Ethos or the like. The other thing was I had the feeling that conical barrel of the Explore Scientific was a little under sized when compared to the Pentax and a few other eyepieces I had at hand, not a major worry but I expected better.

Saturn on axis did not seem to show any more detail in one eyepiece or the other but the moons did show better every night in the XW 5mm but we are only talking a marginal degree here not black and white, my choice would be the Pentax, having said that though the 4.7mm is a good planetary eyepiece but is a little let down in my books by the very edge.

Messier 3.

This is not as bright as the Messier 5 globular but it very high up in the sky for me for a long period of time, it is 16.4 arc minutes in size and a little below the 6^th magnitude and is a fine sight in even a small scope. The power here is maybe what I would normally use on such a target at x200 plus, M3 whilst large is also tight and needs opening out. However the cluster looked really good in my dark skies and the stars stood out like the proverbial diamonds on black velvet, with no Moon in the sky it reminded me of the black album cover of Spinal Tap’s, Smell the Glove, ‘how much blacker can it be’, maybe one day I will get to somewhere like Namibia.

I digress, I think the thing I love about globular clusters is this twinkling against the black sky and there are a few in the sky where we as amateurs can really open them out and see them at their best. There is always one part of me that would love to see any of them through something really large though, 30 inches plus, what a site they must be. For this type of target the Explore did a fine job though I think the light transmission and very slightly less power helped the Pentax shine through, but it was a close call.

Antares.

I made a point of revisiting this star to see if I could split the double again, having done it only once before in hundreds of attempts, I was not about to hold my breath. In total I looked at Anatres 6 times in this test but on only two nights did I decide to stay on it due to poor seeing, it only gets 21 degrees above the horizon from here and that is not as much as you would think. As I said with 4 nights of a rolling boil and nothing very much in the way of point light source to look at this can be hard work, it is a morning split in my opinion and I really must get up and try it. Apart from spending at least two hours looking at this star with the two eyepieces and not seeing anything that even told or suggested to me it was even a double, I recorded a failure to see. The one thing that I did feel was that the star seemed redder in the Explore Scientific eyepiece, a feeling that I always had when using all of the Meade UWA’s that I owned, they always seemed to make colours more colourful which personally I do not have a problem with but fully understand that planetary observers want a neutral rendition of a disc. As a complete one off I turn the scope up to the famous double in Cygnus and sure enough the two did look more yellow and blue.

Messier 57.

This is something that I had great plans for this year and basically have done nothing, in fact I believe this is the first time I have viewed it. Being well below naked eye visibility and having low surface brightness I was wondering for our deep sky fans whether this was a good test target. Fully understanding that the scope was never going to show the centre star at magnitude 15.3, I wanted to see if there was mileage in the better transmission I believe the Pentax XW 5mm has. I think this is about as much power as I ever want to use on the Ring Nebular with this telescope but I would say after about a hour and half in a dark sky with very good transparency, the Pentax was better but to my eyes not by much. This then would be a clear choice for the deep space object hunter where every tiny bit of transmission is life blood. It may well be the case that orthoscopic eyepieces like the BGO’s have better light transmission figures but I believe many trade the small difference for the extra field of view and 20mm of eye-relief.

Conclusion,

Well after the shock of finding ‘ Mr Messier, the comet ferret’ as he was nicknamed on the Moon and seeing the crab nebula there as well, what do I think of these two eyepieces.

There is a large difference in the price of these, for me here the Pentax XW 5mm is more than 3 times the cost of the Explore Scientific 4.7mm UWA. This is itself is enough to say that they should not be compared, I disagree, the 4.7mm held its own very well indeed and should not be over looked as an addition to any collection of eyepieces. I do wonder though whether my old Meade 4.7mm UWA was not a little better, we will never know. The Pentax was stronger in almost every way but not by a massive margin and even this fine eyepiece had a few faults that I could pick up, so there is no perfect eyepiece. I would not be so bold as to say that everyone should have one of these but if you are looking for a top quality eyepiece then the XW 5mm would be very hard to better. If however you are on a tighter budget but still what a very good performer then you could do a great deal worse than the Explore Scientific 4.7mm, which for the money (119euros from Teleskop Services Germany) is nothing short of outstanding value.

I would again like to extend thanks to Dani in Sofia who was kind enough to loan me the Explore Scientific 4.7mm.

Alan.                    

[John]

Another cracking review Alan - great work again

I love my XW 5mm but I have to confess that I've only used the ES 20 / 100 and that was a super eyepiece so ES can obviously turn them out too.

[Damo636]

Very nicely done again Alan, fine work!

[estwing]

stunning report Alan, thank you..

[avtaram]

A very informative and detailed report Alan.

Avtar

[michael.h.f.wilkinson]

Nice report as ever. The 13mm eye relief of the ES 4.7mm is a definite non-no for me (still very good in comparison to an ortho of the same focal length). I have seen several EPs with the conical barrel you describe. My first was the TMB Paragon, and the WO zoom also has it. I quite like it, as it does provide a measure of safety without the annoying snagging of an undercut barrel on compression rings and the like.

[alan potts]

Michael,

The conical sleeve was just too small and really did annoy me at times but I know what you mean about snagging of the undercut ones. Strangle as it is I never seem to have problem with Tele-Vue eyepieces direct into a TV diagonal it is when one of the Chinese reducers comes into the mix I see the problems, I don't have a TV 2-1.25 reducer and they don't provide them with diagonals. Must buy another, I never seem to have enough of them, though 2 inch plastic dust caps could be cheaper.

Alan

[Fozzie]

Great report, enjoyed every word of it.. Makes for an interesting question for all those on a lesser budget then pentax and TV.. Is the jump in price the equivalent to the step up in quality?

[alan potts]

Fozzie,

I don't think there are too many horror stories on the market these days, customers will not stand it and why should we.

I was not able to test the two in my F10 and F15 scopes, If so I would be able to see little green men on the Moon. However I firmly believe the F10 performance of the 4.7mm would be good enough for even the likes of me, not that I am special or anything, to wonder if the extra money is worth spending. Then I would spend it anyway.

Alan.

[michael.h.f.wilkinson]

Great report, enjoyed every word of it.. Makes for an interesting question for all those on a lesser budget then pentax and TV.. Is the jump in price the equivalent to the step up in quality?

I have always abided by the rule that I only replace a piece of kit if I can see and am (mildy) annoyed by its limitations. I used decent but not TV Plossls for years, and only upgraded the 10mm to the Vixen LV 9 and 7mm due to eye relief issues. Only much later did I get a premium EP (TMB Paragon 40mm) and started upgrading to super and ultra wide-field EPs. First try to get the most out of what you have (and can afford) and only when it starts limiting you, get something better.

[Fozzie]

Apologies my question might be in danger of detracting from the excellent report.... i was mearly musing, in the hope of bringing some comfort to those on lesser budgets that maybe (even though we all aspire to the best) you can 90% of the performance for a very good budget if you do your research and buy wise..

[michael.h.f.wilkinson]

Apologies my question might be in danger of detracting from the excellent report.... i was mearly musing, in the hope of bringing some comfort to those on lesser budgets that maybe (even though we all aspire to the best) you can 90% of the performance for a very good budget if you do your research and buy wise..

Absolutely. I got a 4mm planetary EP for an absolute song for my kids' mini-Dob, and checked out the quality in my 80mm F/6, and it was really nice. Decent eye relief, good correction, especially in the centre, only losing a bit towards the edges with respect to higher grade EPs. In faster scopes, the differences are bigger. Don't forget, the observer is more important than the optics in this business.

[John]

There are eyepieces that deliver 100% of premium performance for a lot less cost if you are prepared to sacrifice a wide field of view and / or longer eye relief.

Orthoscopics such as the Baader Classic's and Genuine orthos, Astro Hutech and Fujiyama orthos and Tele Vue plossls can all be purchased for £50 or less on the used market but, within the confines of their narrower field of view, deliver as much if not a wee bit more in terms of pure optical quality as the Ethos, Delos, XW's etc. Worth bearing in mind if you want top quality eyepiece performance now and are happy with a 40-50 degree field of view.

[alan potts]

Fozzie,

Having a box or case full of top eyepieces don't make you a better astronmer. I have seen most if not all of the Sky ar Nights over the last 12 years and I never remember seeing a TV or Pentax in one of Sir Patricks scopes and I think he knew a thing or two.

As John says orthos and TV plossl give fantasic results but with a few small drawbacks which he covered, when I started back inthe 70's there were no 100 degree FOV, or 82 for that matter, othros and plossl were just about king and still sit well with me.

Alan

[Fozzie]

Having a box or case full of top eyepieces don't make you a better astronmer.

Alan,

Couldn't agree more, I think patience and determination are just as important if not more so in a number of ways.. everybody and every observation is unique, For instance the best view of Saturn I've had this year was with a evo90 and a stock 10 mm, but I was delighted and greatful to witness it..

to be honest I'm feeling a tad misunderstood with the original question. I was simply pondering whether that the performance offered on the high end eps really matched the relatively large jump in costs...

In no way I was advocating everyone should have this or that as it will make them more accomplished.

This is a great review, a pleasure to read and Ive enjoyed taking the time to think about the comments as I respect 110% the time, dedication and experience putting it together and then the desire to publish for the benifits of everyone here... looking forward to the next one.

Ta

Fozzie

[John]

.....to be honest I'm feeling a tad misunderstood with the original question. I was simply pondering whether that the performance offered on the high end eps really matched the relatively large jump in costs...

It's a perfectly good question. The answer from my experience is that an eyepiece that costs 2x or 3x as much does not deliver 2x or 3x the performance. Nothing like that in fact. The biggest improvement you will get is moving from the eyepieces supplied as standard with the scope to something like a BST Explorer / Starguider or similar. This step will cost a bit under £50 per eyepiece and the improvements are really tangible. From there on the performance gains get smaller and smaller even though the additional investment to achieve these small upward steps can remain large.

When you get to the differences between the two eyepieces featured in this report, for example, as you can see from Alan's report, the additional £150 (approx.) that a Pentax XW 5mm costs over the Explore Scientific 82 / 4.7mm buys marginal or subtle improvements at best.

In the light of this reality individuals can then make choices on how they spend their money in the hobby

[DRT]

I have an ES 4.7mm winging its way to me now and reading this report has made me excited about its delivery

I agree with the comments above in terms of the quality/price curve. It is true of most luxury products that the biggest jump in quality is at the low end of the scale and the improvements beyond that become marginal. I have mentioned before on this forum that abother passion of mine of wine. I have often paid the price of a Nagler 31mm for a bottle of wine but can still appreciate that the biggest jump in quality occurs between £5 and £10 on a supermarket shelf. Beyond that it is all about marginal gains, in the same way as it works with eyepieces.

[vlebo]

Very interesting topic. I have only ever owned ( and still have ) Pentax eyepieces .  Please do not think I am bragging but when I bought my scopes , 300p Flextube and a 120 Equinox , Pentax eyepieces were recommended because of quality and I am a spectacle wearer .  So amongst all the expense and excitement I purchased , along with my scopes a 30mm and a 20mm XW. I no longer have my scopes but still have the XW's to which I have since added a 10mm XW.

I am now looking for another scope and would like to finish off my eyepiece set with a 7mm XW. While it would be nice to finish off my set of XW's it would appear spending upwards of £255 may not be necessary. I am now wondering which eyepiece or two , maybe a 5mm also , would be good alternatives to my Pentax collection.

Chris

[DRT]

My ES 4.7mm arrived this morning. It's a very nice piece of kit. I only managed to get 5 minutes with it on the moon through my 150 Newt and was very pleased with the clarity of the view. I'm looking forward to spending a bit more time with it and hopefully my 6.6mm will arrive tomorrow

[John]

Congratualtions on your ES 4.7 Derek

Very interesting topic. I have only ever owned ( and still have ) Pentax eyepieces .  Please do not think I am bragging but when I bought my scopes , 300p Flextube and a 120 Equinox , Pentax eyepieces were recommended because of quality and I am a spectacle wearer .  So amongst all the expense and excitement I purchased , along with my scopes a 30mm and a 20mm XW. I no longer have my scopes but still have the XW's to which I have since added a 10mm XW.

I am now looking for another scope and would like to finish off my eyepiece set with a 7mm XW. While it would be nice to finish off my set of XW's it would appear spending upwards of £255 may not be necessary. I am now wondering which eyepiece or two , maybe a 5mm also , would be good alternatives to my Pentax collection.

Chris

I've tried a lot of eyepieces Chris and my current feeling is that you won't find a better wide angle, long eye relief eyepiece than the Pentax XW, certainly in the focal lengths of 10mm and below. The Tele Vue Delos seems to have matched the XW's but I don't feel they have surpassed it.

My advice would be to stick to the XW's if you want more eyepieces. I've used the 10mm and 7mm and currently own the 5mm and 3.5mm XW's and they are really superb. I used to have Naglers in these focal lengths but the XW's are a small step up even on those I feel.

[vlebo]

Congratualtions on your ES 4.7 Derek

I've tried a lot of eyepieces Chris and my current feeling is that you won't find a better wide angle, long eye relief eyepiece than the Pentax XW, certainly in the focal lengths of 10mm and below. The Tele Vue Delos seems to have matched the XW's but I don't feel they have surpassed it.

My advice would be to stick to the XW's if you want more eyepieces. I've used the 10mm and 7mm and currently own the 5mm and 3.5mm XW's and they are really superb. I used to have Naglers in these focal lengths but the XW's are a small step up even on those I feel.

You are probably right John and i probably will stick with the XW's but it will be nice , at some point , to be able to compare  a few less expensive eyepieces to the Pentax and see if there is a significant difference.

[alan potts]

I hear what you say John and if you cast your mind back to the review I wrote on the 3.5mm Delos and Pentax in the end I would have kept the Pentax, and I think you know how difficult that is for my keyboard to type.

Delos are excellent there is no doubt but as you have said many times how good would Pentax be if they had set out to make an astronomical eyepiece and not a birding/hunting scope range, I think we know the answer with the XO even though I do not have one..

I can see myself dropping the 7mm Nagler in favour of the XW in the near future, but I want to assess the new scope line up first, there are some of my eyepieces that now stay in the case since I sold the GSO 150 RC, it is funny how you have little groups for different scopes. At least now I am making an effort to give the 21mmE some scope-time.

Alan

[John]

Your 21mm Ethos will really come into it's own when you have your big dob Alan. If you can get hold of a Paracorr the eyepiece should be sharp right across and the exit pupil will still be a very useable sub 5mm. A match made in heaven I'd have thought

[alan potts]

John,

It was one of my many question to Sumerian, with it take a 21mm E and Parrcorr, the answer was yes without issue even horizonal.

I have taken Moonshane's Parrcorr, it is an older one but the scope isn't F 3.5 of something like that, even I do look to save money when I can. I can always up-grade at a later date. The good thing about buying TeleVue is you are never going to lose much when you move it on.

Alan.

[Dude_with_the_tube]

Hi Alan,

i few heads up for your questions/queries.

pentax Xo 5mm will not be miles ahead of Delos or Pentax XW.visual gain will be very marginal,this is the area where people are trying to squeeze out that tiny little gain in detail what for us day to day users will be practically impossible to see(UK skies limit).We are talking literally a very small increase in detail of something.If you have and I assume you do,Delos or Pentax XW,i wouldnt even worry about getting pentax XO.Also keep in mind that Pentax Xo has very tight eye relief.And i mean very tight of 3.8mm only.If you have been used to Pentax or Delos generous eye reliefs,you will be in for a shocker.

As for the paracorr,you are correct,type 1 is meant for scopes with F ratio down to F4 where type 2 is for f3.5,again,type 1 will work with ANY eye piece you through at it and will work splendidly.you can rest assured,optically there will be no difference between them.Actually type2 has longer barrel what has caused issues for some users.type 1 is easy to use and there are setting tables available from Televue home page for both type1 and type2.Again upgrade from type1 to type2 is questionable and i would say not worth the money,unless you can find one super cheap and want an up to date equipment.

thats my 5 p