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F15Rules

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Posts posted by F15Rules

  1. I once owned a really interesting and very rare Unitron Polarex 4" F15 refractor..at the time I didn't know what it was, or it's rarity, and I posted a while ago on SGL's "Show us your refractor" thread the story of how I came by the scope..and how, unwittingly, and in my ignorance, I had the scope modified in a way that destroyed it's historical and rarity value. You can read all about it here:

    In the post above, I included the only photo I have of the scope in it's "post modification" stage.. 

    Well, today, going through some old family videos, I came across a short (c 28 seconds) sequence in which I had filmed the scope sitting proudly in our lounge. I thought it might be of some interest to colleagues on SGL, so I am posting this below. Please bear in mind that the original video was recorded almost 30 years ago, by me, on a home video camera in the living room of the house we then lived in..it was part of a video of our two young children playing, which of course I've not included. So today I simply filmed the video showing on our TV with my Android phone, so I apologise in advance that the quality of the film isn't the best..but I think it's good enough for you to see what the scope and mount looked like after it was modified with the new, long tube..

    Also, I now know that the scope in it's original, folded short tube form was known as a (extremely rare!) Unitron Polarex Model #132c. This is where the memory starts to hurt more! - I found a very interesting video on YouTube of my exact scope, as I bought it in either 1990 or 1991, from the Scope City shop in Liverpool. You can see the video of the original short tube folded refractor, identical to the one I had, here:

    I believe it was in c late 1991 or very early 1992 that I had the scope altered by Orion Optics (at that time based in Crewe).

    I should stress that OO did nothing wrong..they actually made a nice job of the conversion, (including the UNITRON and Polarex tube decals), and offered back to me the original parts which were removed as part of the conversion..but I told them to skip most of them as I a) had no idea of the rarity of the original folded design and b) I had no intention of ever restoring the scope to it's original state! 

    Anyway..I've attached the above link to the YouTube review of the original folded design scope, as I think it will be of interest to refractoroholics like me, so you can see the scope in it's "before" and "after" states.

    I should also add that the equatorial mount and tripod were never modified and remained original. That mount and tripod were an engineering work of art as I hope the videos will show..the machining and design was just beautiful, right up there with Takahashi IMHO.

    I hope you can make sense of all of  this and enjoy the story🥴😊.

    Thanks for reading.

    Dave

    • Like 5
  2. Magnus, thanks for starting this thread, it's been a while since good Maks were the subject of a decent conversation! I think perhaps they sometimes get mistakenly identified with an SCT design and yet in their optical performance I feel they approximate much more closely to a high quality refractor.

    I've owned 2 M603s, one each of MK66 and MK67 and a wonderful Lomo Ylena 150..all were excellent scopes and I truly wish I still had one now. The Ylena was F14 and the Intes/Intes Micros from memory were I think F10-F12.

    All were very solidly built, with superb optics and beautiful purple coatings on the corrector plate.

    Here's a link to a thread I posted about a comparison with my Ylena 150 and an excellent Lyra Optics 4" F11 refractor. 

    Also a few shots of the Ylena.

    Great scopes, last for years and put up the closest views to a fluorite apo I've seen👍

    Dave

    Ylena 150 Mak2.jpg

    Ylena 150mm Mak1.jpg

    Ylena 150 Mak 3.jpg

    • Like 3
  3. It's a similar story for me, John.

    All of my 4 scopes are 12 years old or more, in order as follows:

    Carton 60mm F12 achromat - c34 years - I'm at least the 3rd owner, probably more

    Vixen 102M 4" achromat - c30 years I'm at least the 3rd owner, probably more

    Tak FS128 F8.1 apo - 22 years, I'm the 2nd owner

    Long Perng 80mm F6 achromat - 12 years, I'm the 2nd owner

    The Tak is in mint condition. I'd describe all the others as being in very good used condition.

    The great thing with refractors is that they are relatively low maintenance, and with care for the optics they can last almost indefinitely 🙂👍

    Dave

    • Like 1
  4. 9 hours ago, John said:

    Like the term "Super Apochromat" which is being applied to a few refractor lines now ?

    Back on the Morpheus range, does the actual AFoV of the 17.5mm Morpheus match the spec of 76 degrees ?. Has it been measured independently ?

     

     

    Hi John,

    Only just seen your question, and of course it's now been very fully answered by Don Pensack👍.

    He clearly likes the eyepiece, regardless of whether it truly delivers a full 76 degree field. Visually, it's very difficult to detect relatively small differences versus other similar eyepieces even if exactly the same focal length..I guess you need to use a drift method or similar, and I've never looked through either a Delos or ES.

    I do think that the contrast and edge of field performance of the Morpheus range stand up very well to comparison with my own informal  "benchmark" range, the excellent Pentax XWs..the latter of course are "only" 70 degrees, so whatever the Morpheus' actually measure, they are comfortably wider than the Pentax's..

    And still much cheaper than any of the other competitors 👍.

    Dave

    • Like 4
  5. 1 hour ago, Sargares said:

    So, thinking about future additions to the collection. 
     

    I may add the Morpheus 6.5 and 12.5 as that’ll give me magnifications around 200 and 100x which are gaps I have right now. The 6.5 would be the most powerful eyepiece in the stash. I think 203x is enough to get reasonably regularly use. (1200 focal length + 1.1x Barlow from coma corrector) 
     

    How do those two fit into the set? I know the 9 and the 17.5 are a lot of peoples favourites. I’d be more inclined to go over budget at the 12.5 size IF that one is one of the weaker ones in the set as it’s a magnification that’s likely to get a lot more use. 

    I have the 9 and 17.5 and I like them both very much. I've owned the 14 and used the 12.5, and I wouldn't describe any of the above as a "weaker one", other than possibly the fact that the 14 shows a little field curvature ( but it's better than the Pentax XW 14 in that respect, which is why I swapped my XW for the Morpheus). 

    At the 12mm point I have a Nagler T2 12mm which is a great ep, and there's not enough difference in the Nagler 12 and the Morph 12.5 to justify having both. But of the 12.5 and 14 Morpheii I would go for the 12.5 if I already had the 9 and 17.5 as you and I do..I'd also get the Baader 2.25x barlow (either of them, they are both optically great, although the zoom 2.25 has much better build), and you would then have 3 great Morphs each offering two worthwhile differences in magnification.

    To illustrate this, my scope has a focal length of 1040 mm..so...using the above 3 eps (9, 12.5, 17.5 plus the zoom 2.25x barlow) I could get the following powers:

    55x, 83x, 115x, 133x, 187x, 260x

    To me, that's a great spread of available powers that could cover most needs on most nights👍.

    Dave

    • Like 2
  6. 13 hours ago, RobertI said:

    Vega a double? I had to check this but you’re right!  Not sure whether I could get this in the 4” frac but will try for sure

    Thanks Robert..

    I've often seen Vega's optical companion with a 4" refractor..

    image.png.e3b5bf6ee007b7ae94d8bd228e157530.png

    If you look at the position angle graphic above ( courtesy Wikipedia), I think the companion is at a position angle (PA) of about 220 degrees..however, with a refractor and diagonal, north is at the top but east and west are reversed, so looking at the graphic above, if Vega is at the centre, the faint companion would be at about the 8 o'clock or 140 degrees position..( I hope that makes sense!). 

    Jock, Nick,

    Thanks for your kind remarks🙂..and I'm quite relieved that I'm not alone in struggling to see the Propeller!

    Dave

    • Like 1
  7. Thanks Magnus..your reaction made it worth writing down my thoughts from last night's session, as I had been feeling rather frustrated myself about my recent lack of  "skytime".

    As I locked up last night, the last thing I saw, peeping up to my east, was the Pleiades..much as I love the summer and it's constellations, I always find the first glimpse of the Pleiades very exciting as a portent of the arrival of mighty Orion, most magnificent of all IMHO..now that's worth getting excited about!👍😊

    Dave

    • Like 1
  8. Well, last night was the first proper session I've had for some time, and having started with low expectations at 11pm with 50% cloud cover, the skies gradually improved and I ended up staying out til 1.30am👍.

    Conditions: light breeze, warm, with 50% cloud cover to begin with and moderate seeing (good transparency though), improving steadily to good seeing between c midnight and 1.30am. By midnight I could see structure in the Milky Way with the naked eye, and by session close the visible M Way arc extended over 50% of the way to each horizon.

    Equipment used:

    Tak FS128 F8.1 apo and (briefly) Vixen102m F10 achromat

    Celestron Axiom LX 31mm 82 deg

    Celestron Axiom LX 23mm 82 deg

    Nagler T2 12mm

    Morpheus 9mm

    Vixen LV 10mm and 5mm

    Baader Zoom Barlow 2.25X

    I should say that this was not at all a planned session, and so I just decided to firstly look at Jupiter and Saturn, fully expecting the skies to cloud over soon after I got set up.

    At 11pm both planets were fairly low down (we sit at the bottom of a steep lane), and seeing was only moderate at best to begin with.

    Jupiter was very bright, but as is so often the case, the view became quite mushy at much over 100x, such that anything more actually diminished the details visible: however, Io's disk was clearly visible close to the planet. 

    Saturn, although much fainter to the naked eye, looked sharper, and I got an early glimpse of the Cassini Division and I think 3 moons (Titan of course, plus 2 others).

    I then decided to use my relatively new to me UWA Celestron Axiom 31mm 82 degree for its' first extended session. This is by some margin the largest eyepiece I've ever seen and weighs in (I kid you not!) at 1.4kg! Fortunately the 2.7" Tak focuser is very robust and once I'd rebalanced the OTA I had no issues and the rig worked flawlessly. For a good 20 minutes I just cruised around Cygnus, starting with Albireo (beautifully defined colours against a sparkling sea of innumerable stars as the Milky Way readily resolved in all directions). The Axiom is extremely sharp right from the centre of the FOV, right out to a good 97/98% of the 82deg FOV - and, thanks to the very smooth and solid rotating eyecup, very comfortable in use. I could see the sharp field stop and whole FOV very readily: I think that for me, 82 degrees is as wide as I'd want to go, but there's no denying that for low power widefield views, this eyepiece delivers wonderful views. In the FS128 it provides a 2.45deg FOV and magnification of 33X, lovely.

    I moved along the Northern Cross, to Sadr, perhaps the "densest" part of the Northern Sky Milky Way in terms of individual stars, and I just enjoyed the classic "diamonds on velvet" effect. 

    Switching soon after to my (again new to me) Axiom LX 23mm, again 82 degrees, so delivering a respectable 1.82 deg FOV, I was really reminded of my much missed Vixen LVW 22mm 68 degree unit, just as sharp, but with a noticeably wider FOV than the c1.51 degrees of the Vixen.. the latter gave me my best ever views of M42, bar none, and I am quite excited to see if the Axiom can match or exceed the LVW in a couple of months when Orion returns 🙂.

    Dropping down from Cygnus through Vulpecula, I was delighted to chance upon the Dumbbell nebula, and was very pleased at how bright it looked in my modest 5" aperture (it's quite bright at c mag.7.9).

    I then turned to Lyra, such a small but rich group. I love to checkout Vega as it was one of the first stars I ever observed back in the 1970s as a teenager: like many others, I used a 60mm F15 achromat at that time, so to see a bluish tinged Vega was quite normal, and rather attractive. Seeing it now though, as it really is, through an apochromat, as a flawless white diamond, is almost a spiritual experience..I immediately looked for Vega's mag 10.5 optical double companion, and there it was, very clear in the Tak with direct vision, in the c.7 - 8 o'clock position (refractor view with diagonal). It's readily seen in a 4" scope, but may take a moment to "pop out", until the observing eye adjusts to the overwhelming brightness of Vega herself.

    From Vega on, inevitably, to the double double, Epsilon Lyrae. As soon as I aligned them in the Axiom I popped in the Nagler T2 12mm..this is a cracking eyepiece, useable in both 1.25" and 2" focusers, and it has wonderful contrast. At 86x I was presented with two lovely pairs of small, but distinct "bullseye's" each pair at right angle to the other, and perfectly white mini "headlights"..adding the Baader zoom Barlow to the Nagler ramped up the magnification to 195x. This pair will really reward higher powers on a good night, the extra power increases contrast, and you see very clear, black space between each pair, wonderful!

    Before leaving Lyra I had to check out M57, The Ring Nebula. As I know just where to find it, I left the Barlow in the Nagler, aligned the scopes' finder with the expected position of the Ring (I always struggle to see it directly at c mag 9 in my RACI 9x50 finder) and there it was, actually quite a bright and large "ring donut" object, with a clearly visible (with averted vision) faint star to the 3 o'clock position, outside of the Ring. I estimate this star to be between mag 11.5 and 12 - does that sound about right? I've never seen the central star of this planetary nebula, I believe it's mag 13 or fainter, so probably visually beyond the Tak (and my ageing eyes!).

    I find that M57 eats up the magnification, and have used 300x on excellent nights with little deterioration in the image.

    I couldn't go back to the planets before first checking out M13 in Hercules: easy to spot in my finder scope, I went straight in at 195x..at this power, and even with an 82deg fov, the object appeared large, and unmistakably as a large ball of individual stars..I'd estimate that between at least 30 and 50 individual points of light were resolved, quite a few directly and many more with averted vision, stunning. I am one of those, however, who just cannot see the Propeller asterism -even in photos with it outlined, I struggle with it. What's your experience at 4-6" aperture?

    Finally, and by now getting tired but also elated at the views I'd been seeing, I spent the last 20-25 minutes of the session on Saturn and Jupiter. I'd put up my recently restored Vixen 102M F10 achromat next to the Tak (see photo below), and I was keen to see how it would be on the gas Giants. I started with Saturn and was delighted to get a nice clear view of Saturn and Titan close by..by now, Saturn was well past due south, and partly affected by a nearby streetlight overspill, but I could see, partially, the Cassini Division, and a very nice, sharply defined creamy coloured main disk of Saturn itself.

    I then turned the FS128 to Saturn for comparison, and the difference was startling..don't let anyone tell you there isn't much difference between a 4" and a 5" objective - especially when the 5" is a fluorite doublet! I could clearly see the sharply defined Cassini division all the way around the ring, as well as a darkish band on the planet itself, and at times I suspected the shadow of the rings on the planet but couldn't be completely sure..the dual focuser of the Tak did make fine focus easier, and the Tak took 195x magnification no problem - and might have taken more if time had allowed.

    Finally, to Jupiter (with the Tak only, I was getting tired, and with the last ten minutes or so I wanted all that time with the better scope).

    I went straight in with the Morpheus 9mm at 115x..the view was pin sharp, and almost too bright, but I could immediately see the shadow of Io to the far "right" (west, I think, refractor view with diagonal) at c 4 o'clock position and approximately 10% of the way across the planets' disk, just stunning. I could also see at least 5 bands. I tried the Morpheus with the zoom barlow at 260x..the image actually held up quite well, but I did start to see floaters, which I found rather distracting..a hazard of getting older, sadly.

    But all in all, a most enjoyable, even exhilarating night, and I feel very much more motivated to welcome the autumn and winter, knowing my scopes are at their best and raring to to go!😊.

    Thanks for reading..

    Dave

    IMG_20210813_010916407.jpg

    • Like 25
    • Thanks 1
  9. On 20/07/2021 at 10:36, John said:

    Here is a little info on the main features of Jupiter:

    Jupiter_belts.jpg.b982b95cb65706b4186219265c6023bb.jpg

    jupiterfeatures.jpg.53afcbb376462bb262d278699eeb2a1d.jpg

     

    I also use the Virtual Planet Atlas (freeware), Stellarium and Cartes du Ciel for moon and GRS positions.

    Thanks for these images John, very useful reference points.

    It's a sad fact that since I had my FS128 services and lens cleaned by Es Reid on 7th June, I have not had one session with the scope since that time. 3 main reasons:

    - lousy night time weather here, even after the day might have been sunny!

    - a plethora of short breaks, 5 in all, due to family commitments (catching up post Covid lockdowns etc), leisure breaks , 3 of 4 nights each, two of which had been postponed due to Covid, so had to "use them or lose them"..

    - and this past week, 3 good nights, during which we have been home but my wife caught a nasty bug (not Covid) and had to go to bed early on 2 nights ( didn't have the heart to disturb her by moving about, she's a very light sleeper), and one night after I'd been working hard in the garden all day, up ladders, using chainsaw etc etc - and I was just too dog tired to stay awake!

    Not moaning (honest!) but I have felt a little unlucky in astro matters, but very blessed to have had some very nice trips around the country, both seeing family and also having some nice leisure tours of Devon, Sussex and Surrey..I know many people who have yet to leave our village for the first time in over 12 months due to the pandemic!

    Sorry to go off topic John, that ED120 of your sounds like a cracking scope, and really delivers for you in a way that the two I previously owned just didn't. Great planetary report!

    Very glad you had such a rewarding session👍😊

    • Like 2
  10. 4 hours ago, Nakedgun said:

    F15Rules,

    When I "downsized" some years ago, selling my 18" newt, two triplet refractors and G-11 mount, I also, quite foolishly, included my FS-128 with that group, regretting the decision to this day. Not wanting to buy used,  Agema has come to my rescue.

    Sometimes, one must learn the hard way.

     

    .

    I totally get that, NG..there don't seem to have ever been many FS128s in the UK - I'm aware of 3 people who have owned one and sold one, and each of them said they bitterly regretted selling them.

    I was lucky to find mine 4.5 years ago, a 1999 model in like new condition and hardly used, complete with a lovely '98 Tak EM2 mount. For me, it was hoped to be an all round scope, for the rest of my life. 

    In these days of, it seems, reducing interest in visual and more in AP Astronomy, it's great to see a manufacturer believing so much in the value of excellent high end, visually targeted doublets, that they will bring a new model like yours to the market - and made in the US, too!

    Many thanks for sharing your lovely new instrument with us.

    Dave

    IMG_20210804_200856572.jpg

    IMG_20210804_200906877.jpg

    • Like 3
  11. 4 hours ago, Andrew_B said:

    Is it heavy relative to other scopes that size? It looks so solidly made that I'd expect it to weigh a lot

    Andrew, my FS128 weighs 7.5kg, about 2kg less than the Agema I think?

    The Tak has a large tube, about 165mm at the dewshield and c 145mm for the OTA IIRC, but is actually very pleasantly lightweight, but solid.

    And of course the other big difference optically is that my FS128 has the fluorite element at the front of the doublet, hence the FS (Front Surface) moniker.

    The Agema looks like a lovely, high end scope and I wish them all success with it👍..but my FS128 will not be going anywhere 🤗😊.

    Dave

    • Like 3
  12. On 03/08/2021 at 14:54, JeremyS said:

    For amusement, here’s the Pentax XP 3.8 next to my Tele Vue Nagler 26 T5

    8EFE653E-D92A-452A-BD28-F7E073372929.thumb.jpeg.0bbcccebabdd39b3f262b8d4de210e87.jpeg

    Well,at least you won't need a handle to lift that little beauty, Jeremy:rolleyes2::)..

    Joking apart though, it looks to be in mint condition..I imagine the eye relief is tight, and fov small ( 30-40 degrees?), but I could also imagine it being a great double star splitter too?

    Nice find!👍

    Dave

    • Haha 1
  13. That's a lovely restoration/creation Steve, just looks the business!

    I will watch with great interest for your first light thoughts..

    Where would we be without Es Reid and his magic, eh??👍

    On 01/08/2021 at 20:10, Stu said:

    Looks absolutely fabulous Dave! Look forward to hearing how it performs, should be fun 👍👍

    ...that's what a combination of moving house and keeping count of Johns' posts does to you Steve, oops, STU!!😂🤣😂

    Steve..sorry, Dave🥴😊

    • Haha 3
  14. 7 hours ago, Pixies said:

    Congrats John. Thanks for all the helpful posts over the last year. As well as all the advice, your observing reports are often drivers for me to try new challenges or just even get out there.

    Still not sure about the lens-licking though!

     

    Agree with the first paragraph 100%👍..

    As regards the "lens licking" though, I think we have Jeremy to blame, er, I mean, thank, for that though..also @MikeDnight too

    "But would its mirror make your mouth water and your heart skip a beat? Looking at the lens below, don't you feel the need to lick it, or am I just weird?" - quote by Mike in a thread that "inspired" Jeremy's Pearl of a Thread!!

    John is far too sensible to encourage such disgusting habits!!😱😂😂

    Dave

    • Like 1
    • Haha 3
  15. 4 hours ago, rl said:

    Thanks for putting up this post. I saw the advert and was not sure whether to be sympathetic or suspicious; others with a similarly cynical disposition as myself may have had the same dilemma. 

    Let's wish him and his wife well and be grateful for what we've got.....

    I can vouch for Denis' reputation and quality of his work..he cleaned and serviced a pair of binoviewers for me about 3 years ago, and made a lovely job of it too.

    Denis is better known on Cloudy Nights in the USA and enjoys an excellent reputation. Put it this way, if I could afford this last pair, I'd buy them without hesitation.

    With regard to his exit from his binoviewing work, it is our loss but definitely the right decision for his family..we can only wish him and his wife and children well, and pray that his wife can survive this awful disease🙏.

    Dave

    • Like 8
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