Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_lunar_landings.thumb.jpg.b50378d0845690d8a03305a49923eb40.jpg

johnturley

Members
  • Content Count

    148
  • Joined

  • Last visited

Community Reputation

80 Excellent

About johnturley

  • Rank
    Star Forming

Profile Information

  • Gender
    Male
  • Location
    Dronfield, Derbyshire
  1. I think its actually about 35 mm outward travel with a digital SLR (I must check with mine), were you meaning with an eyepiece. John
  2. The current price of a new TOA-150B with tube rings and 7 x 50 finder at Rother Valley Optics is £14,500, there appears to have been a recent price increase. John
  3. Finally picked up my Esprit 150 from Es Reid in Cambridge on 21 September after a 7 week wait, Es tested both the scope and the field flattener last week and found them to be excellent. Interestingly Es also checked over a second hand Tak FS152 the same week, and was able to compare the two scopes, in his opinion there was no discernible difference between them. John
  4. Ordered one from them to fit my Esprit 150 last Friday having read 2 favourable reviews, it arrived today (Wed 9 October), and would agree that they appear to be well made and of good quality, superior to the Kendrick ones of which a have a couple. I wouldn't however give them 10 out of 10 on customer service, I initially asked by email what size I should purchase to fit my Esprit 150, which has a dewshield 8in or 203 mm in diameter, but didn't receive any reply after several days. In the end I decided to order the 8in model, but found that it is a bit on the big side, and could have probably saved myself a bit of money by going for the 6 or 7in version, however I'm not bothering to send it back to exchange for a smaller size. John
  5. I finally managed to get the Esprit mounted up and operational Wednesday of this week. It took longer than expected as unfortunately, due to a misunderstanding, the local engineering firm made the forward support bracket 6 mm shorter than it should have been, so that although I could mount up the Esprit ok, it wasn’t possible to align it with the 14in Newtonian so that the same object appears in the centre of the field of view through both instruments at the same time. As can be seen in the photos the rear support bracket has a small amount of sideways and up/down movement to enable alignment of two scopes. I was a bit nervous about how easily I could balance the scope on my 14in Newtonian, but despite the 12 kg weight of the OTA (around 15kg including tube rings, finder and star diagonal), I managed to balance it up ok (see photo), and with the slow motions working fine. In fact it made wonder how large and heavy a scope I could actually mount on my 14in Newtonian which is on a massive fork mount, maybe the absolute maximum would be a 180 mm f7 refractor such as the CFF and TEC which both weigh around 18 kg, but cost around £16k and £21k respectively, so don’t think I’ll be going that way anytime soon if ever at all. I’ve actually installed my ES 8x50 erect image straight through finder (see photo), rather than the Skywatcher 9 x 50 right angle finder that came with the scope, as the former appears to be of better quality, and has an illuminated reticule, although I know some prefer right angle finders. I’ve also utilised a Baader click-lock diagonal rather than the included Skywatcher one for the same reason, and although there was sufficient travel on the focussing mount to reach focus without the need for extension tubes, I preferred to utilise a 50 mm Baader click lock one, so as to avoid racking out the focuser towards the end of its distance of travel. It also makes it easier to remove the diagonal and fit an additional extension tube for straight through viewing. Although some have posted stating that they did not like the capstan wheel type arrangement for rotating the focuser, I actually quite liked it, and think that it provides a much more rigid arrangement for locking the focuser in a particular position than that on the ES scope. The focusing mount tension screw on recent models has been replaced by a spring loaded locking leaver, and whilst this may please AP enthusiasts, I think that I would have preferred the former. The lens cap which unlike that on my ES Refractor, fits over the dewshield rather than the lens cell, being made out of fairly thick gauge metal is quite heavy, I’m surprised they don’t use a thinner gauge metal or plastic, but it does roughly balance out the weight of the main mirror cover. I can see the pros and cons of either, fitting over the lens cell is probably better for keeping out dust and moisture, but depending on the rigidity of the lens cell, maybe continuously removing and replacing over a long period could possibly effect collimation. I also needed to fit a handle to the one on my ES Refractor to remove or replace it as, because of the way the scope was mounted, I could not fully retract the dewshield to do so. I also find it useful that, unlike on the ES Refractor, the dewshield (which is quite a sloppy fit) on the Esprit can be locked in position via 2 knurled knobs. I ordered the matching field flattener with the scope, but found that it is a bit fiddly to fit, as you need to unscrew the 3in to 2in reducer on the scope, fit an adaptor, then the flattener, then fit the matched extender tube, and then the 48mm to Canon (Nikon or Sony) adaptor, not ideal in the dark, hence I wonder how often I will actually use it in practice. The ES field flattener (which is actually an Ascension branded product from Opticstar designed for triplet APO's in general), came with a ‘T ’thread to Canon adaptor which fitted directly into a 2 in drawtube, and although obviously not a good as the Esprit matched flattener, it might still give quite good results with the Esprit, at least better than using no flattener at all. The larger size in the case of the Esprit matched flattener is because it has a clear aperture of around 60 mm, which I assume is necessary to provide the 44 mm image circle. I looked at a few objects Wednesday (one of the very few clear nights recently) including Saturn, viewing conditions were not ideal, but as expected the Esprit gave much sharper star images than the Newtonian, and under the prevailing conditions also on Saturn, plus as free from any false colour. I could just make out Cassini’s division through the Esprit, but not through the Newtonian (although it does show up clearly through it under good conditions), obviously the Newtonian gave a brighter image, and more moons were visible. The image through the Esprit 150 was though as expected, noticeably brighter than through the ES 127, and Titan showed up clearer. I find it useful having a refractor piggybacked on the Newtonian, as depending on what you are looking at and the viewing conditions, one instrument or the other will give the better view. John
  6. I have bought a number of items from Rother Valley Optics, who are my local supplier being situated just 15 miles (30 mins drive) away, these include two telescopes, a number of eyepieces, filters, and several other items, coming to around £5,000 in total. I have always selected the option to 'collect goods from shop' as this saves on shipping charges, plus I can inspect the goods before taking them away. I have generally found them to be very helpful and have offered good advice, but I was a bit disappointed with them when it came to obtaining a Seymour Solar Filter to fit my Skywatcher Esprit Refractor. According to their website they stock Seymour Solar Filters in a large number of sizes, but not apparently the correct one to fit my Esprit 150 (which appears to be the SF 8376). However when I asked them about obtaining one for me, they were not willing to do a special order, and informed me that I would need to order it myself direct from Seymour in the USA which will involve additional shipping charges, plus probably also import duty and customs clearance charges. Bearing in mind the amount I have spent with over the years, I really thought that they could have been more helpful. John
  7. Classic 1980's Vixen (made in Japan) 4in (102mm) f10 Achromatic Refractor on altazimuth mount with slow motions and wooden tripod, 6 x 30 mm finder, also included Vixen Prism Star Diagonal, 40 mm Kellner eyepiece, and accessary tray. The scope accepts either the classic Vixen screw 36.4 mm eyepieces, or with the included adaptor standard 1.25 in (31.7 mm) eyepieces. In addition there is a lot of travel on the rack and pinion focussing mount, with enables the scope to be used with or without the star diagonal without the need for extension tubes. I have owned this telescope for many years and is in good condition (no chips or scratches on the lens), but I now reluctantly need to sell it to make room for new telescope. Now Reduced to £325 ono Payment by cash or bank transfer (I don't do PayPal) Buyer to collect Contact <private contact details removed>
  8. Finally picked up my Esprit 150 from Es Reid in Cambridge yesterday after a 7 week wait, Es tested both the scope and the field flattener last week and found them to be excellent. Interestingly Es also checked over a second hand Tak 150 the same week, and was able to compare the two scopes, in his opinion there was no discernible difference between them. However when it came to price there would have been more than a discernible difference, the new Esprit 150 (which comes with tube clamps, 9x50 finder, 2in star diagonal, and 28 mm eyepiece) plus field flattener cost me around £4,300 (from FLO), whereas a new Tak TOA 150B (from RVO) with tube clamps and finder, plus field flattener would have cost around £14,500, similar also to the cost of a TEC 160 (and approx. 6 month wait). The scope was very well packed in a substantial case, which in turn was packed into a cardboard box with extra packaging, I gather from Es that it is very rare one suffers from transit damage. The whole scope appeared to be well finished and engineered, substantially better than my Explore Scientific 127 APO, and also an 1987 vintage Astro Physics Refractor that I used to own. In particular the focussing mount was very smooth, and provided 85 mm of travel, as opposed to the totally inadequate 45 mm on the ES Refractor, and think the majority of users won't find the need to upgrade to a Feathertouch focuser, which appears to be no longer offered as a factory fitted option. Surprisingly the tube length was shorter than I was expecting at around 75cm with the dewshield fully retracted, and only some 2-3 cm longer than the ES Refractor despite the extra 9.5 cm of focal length, most of this it appears is taken up in the focussing mechanism. The tube diameter was also greater than I was expecting at around 180 mm (with some scopes the tube diameter is only around 5 mm greater than that of the objective), the larger tube diameter should help to reduce tube currents. Although it is quite a heavy scope for its size, as I was half expecting I measured the weight of the OTA (without tube clamps, diagonal, finder, etc.) to be lighter than stated in the literature at 12 kg rather than 14.5 kg , similar to that of my AP Refractor (which I also mounted piggyback), and is not too difficult for one person to lift. My only criticism (so far at least) was that the layer of felt liner on the tube clamps was very thin (compared to that on the tube clamps of the ES Refractor), and can understand why some people may have had problems with the clamps gripping the scope sufficiently, I do however have some self adhesive felt which I can add on if necessary. I haven't however has the chance to try it out yet, as apart from the weather, I need a local engineering firm to machine some modifications to the tube clamps before I can mount it piggyback onto my 14 in Newtonian, and have spent part of today making a wooden template for a new support bracket for them to machine in aluminium. Will post further after I make my first observations. John
  9. I've never been able to see Triton visually even through my 14 in Newtonian. John
  10. If you are using a full frame digital SLR the 48mm is better, as you can get slight vignetting with the 42mm T thread, with a crop frame sensor it probably doesn't make much difference. John
  11. Brian How much does the filter draw and base, plus the other bits you need, add to the light path. In the case of my 14in Newtonian I have only about 28 mm to spare, and I suspect it will be more than this, in which case I wouldn't be able to reach focus with some eyepieces. John
  12. I think that you need to buy both the base (£54) and the filter slider (£44), and maybe some other bits. I had some thoughts of buying a Baader coma corrector and filter slider, but was put off because I found it confusing trying to work out which bits you actually needed to buy, and instead went for the ES version, which comes with the eyepiece holder as standard. John
  13. Mart Hope you mount arrives ok this week, do let me know how you get on with it, send me a PM if its easier. Having read Johninderby's comments, I am now increasingly thinking of getting the AZ-EQ5, like you from my local supplier Rother Valley Optics, especially as it is already belt driven. Ideally I would liked to have a look at both versions before making my mind up, but as I expect you are aware, they don't have either version in stock or on display, did you have to wait long for yours. Cheers John
  14. That's good, if you add on the cost of the belt modification this reduces the price gap between the two mounts to less than £100. John
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.