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John

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Posts posted by John

  1. 14 hours ago, Littleguy80 said:

    I have the MEF3 micro focuser upgrade on the my wish list for my Tak FC100DF. I’ve gotten on well with the Tak standard focuser though would like the dual speed for fine focusing. There is still a bit of me that wonders whether it would be worth the wait and extra pennies for a feather touch though. 

    I was quite happy with the single speed Tak focuser on my F/9 FC100-DL but the FT micro pinion came up at a good price and I fancied trying one.

    I have read mixed reviews about the MEF3 but many do really like it. With these user fitted add-ons I think the care with which they are fitted can impact how well they work. As I said in my earlier posts, it took me 3 attempts to get the FT micro pinion fitted and working really well and that one does come with quite comprehensive instructions 🙄

    I've never used the More Blue one so can't comment on that. 

    In the past I have found dual speed crayfords (or all brands) rather variable but the Feather Touches that I have used have been "above and beyond", which Is why I started this thread 🙂

    Pity that their retail prices seem so high now but isn't that the case with most really good equipment ?

    • Thanks 1
  2. My 12 inch F/5.3 dob weighed 26kg / 57 lbs in total. About the same as a chinese 10 inch. My base was 18mm ply rather than MDF and the tube was aluminium. I didn't have GOTO fitted though. 

    I had a Meade Lightbridge 12 inch a few years before and that weighed over 80 lbs in total. Again, no GOTO.

     

    • Like 1
  3. 14 minutes ago, Franklin said:

    No one in their right mind would try to observe Venus in a dark sky and most will try at twilight but even then, being so close to the Sun, Venus will not only be very, very bright but also quite low in altitude, not a good combination for high power, high contrast visual astronomy. The best thing to try is to find Venus during the day, when the Sun is still well above the horizon. That way the sky brightness will reduce the glare of bright Venus and the high altitude will help with atmospheric dispersion and unsteady seeing conditions from a low altitude. You don't need fancy setting circles or goto's to do this, as long as you know the general area of the sky where Venus will be it's quite easy to spot. A little trick is, at the end of a nights observing put your lowest power, widest field eyepiece in your scope and focus on the stars, pack up and don't alter the scopes focuser. Next day or next clear opportunity sweep around the general area of the sky where you expect Venus to be and do this when the Sun is still 25deg above the Western horizon at least, be careful NOT to let your scope go near the Sun. An alt-az mount works great because you can start closer to the Sun than you expect Venus to be and just keep panning up and down and AWAY from the Sun till you find Venus. Whilst staring at a bright blue sky and seeing only floaters can at times make your eyes go out of focus and you'll miss Venus when it enters the fov, concentration and practice helps with this and panning low down to a cloud or the horizon for example will help keep your eye focused.

    Best views I've ever had of Venus have been in full daylight. (Wratten #21 Orange works well)

    Of course, when Venus is a morning object all of this is much easier. Using an equatorial mount, set up on Venus and leave tracking till the Sun is up and then you can observe Venus all day long if you wish.

    Great post here from @Franklin 👍

    I don't observe Venus against a dark sky if I can help it. Jupiter also looks at it's best with plenty of light still in the sky. 

    • Like 3
  4. Got SN 2023xif again with the 70mm here on Jersey. Brighter, higher moon plus more blustery wind made it a little trickier and I needed a little more magnification to tease the SN out but it was definite and probably about the same brightness as it was last night, give or take.

    Iota Leonis and Izar were also split at 131x with the 70mm scope showing decent optics I think. 

    • Like 6
  5. I'm on holiday on Jersey currently but I have a small (70mm) scope with me and tonight is nice and clear without the thin high cloud layer that has been present over the past few nights.

    I didn't think the supernova SN 2023xif would be visible in such a small aperture but the transparency is very good here and I was very pleasantly surprised to get a nice view of both the Pinwheel Galaxy, Messier 101 and SN 2023xif shining faintly from it's outer regions. I reckon the SN is around magnitude 11 tonight. I can see stars down to around mag 11.8 or so with this little scope. I'm using a 20mm SWA eyepiece so 21x magnification.

    By far the smallest aperture scope that I've seen a supernova with - previously my ED120 held that distinction. 

    Very pleased to get this SN just in case it starts to fade before I get back home to my larger scopes 🙂

    Also lots of nice views of the Moon, Venus and doubles plus globulars and some of the brighter galaxies (including M 101 of course). 

    Nice little holiday session 😁

     

    • Like 21
  6. 3 minutes ago, Mr Spock said:

    Same here - a full sized bearing. That and strengthening the base has given me a scope that is a joy to use. 

    I need to flock it too, but the size of the tube is putting me off :sad2:

    When I had my 12 inch dob, I flocked the area of the tube opposite the focuser (an A4 sized area) and a strip of the inside of the tube for about 10 inches above the primary surface. Possibly not quite as good as a "full flocking" but it seemed to make a small difference to light scatter and if nothing else gave me some assurance that I had done "something" positive 🙂

    • Like 1
  7. 1 hour ago, Alan White said:

    Focusers make or break a scope in my experience.
    I too see the point in enjoying the interface.
    Do I own a FT, well no I don't, but await one for my Ha scope, its taking its time, been months so far.

    I also happily use a single speed focuser, but its how that focuser works that to me counts.
    China, Taiwan, German, Japan or where ever made is no fuss, as long as it works well.

    One day my Vixen will be decked out with a nice rotatable focuser, but the stock R&P single speed actually work very well,
    its far more rigid than the Tak ones I have used in the past. 
    The Altair 152 5.9 has a very nice, smooth and rotatable focuser, stock with the scope made in China I presume.

    I do think the upgrade path in this hobby can become a hobby in itself and adding bling becomes part of that as well,
    however if that upgrade improves the experience, then why not.

    I understand that FT had a cahnge of ownership due to i think I recal a death, this has intereupted supply,
    hence why I an d I expect other have a long wait.

    My incoming FT is single speed.



     

    I had the Lunt 50mm HA scope with the single speed FT focuser on it a few years back. Bought from the late, great johninderby. A very nice combination.

    It is interesting that the quality of focuser comes one step higher in Richard Suiter's "wobbly stack" than the eyepiece.

    • Like 1
  8. 9 minutes ago, Captain Scarlet said:

    Thanks John that’s a useful chart, and with 90 degree ACW rotation and L-R reflection does correspond to what I saw. Where is it from?

    No problem but I'm afraid that I can't recall the source. I found it on the web quite a few years back and copied it into my "resources" folder. Here is a similar chart which David Knisely posted on the CN forum a few years back:

    post-3169-14074316931971.jpg.b258af1697975042e11ae59d069ac0d9.jpg

     

    • Thanks 3
  9. Really great report Magnus - what a night !

    I have used the chart (below) of M57 and vicinity below to see how faint I could go. The exact magnitudes seem to vary depending on your source. Some are actually variables of course ! With my 12 inch dob from my back yard I got to magnitude 14.7 but I've not reliably seen the central star even with that aperture. I did have some elusive glimpses at times though. I have to be able to repeat something consistently to be confident of having "got it" and I have not got there yet on the M57 central star.

    Refractors can often surprise on just how well they do though - you do feel that you are getting just the best that the aperture / conditions / observer can get with that design I think 🙂

    m57stars.png.3aef8aceea169bb961d70519ee5d9de0.png

    • Like 2
    • Thanks 1
  10. Thin cloud has masked the stars here this evening so I'm having a play with the focuser on my TMB/LZOS 130mm refractor. I've not paid too much attention to the focuser on this scope - it has just worked and worked very well. I don't know the Starlight Instruments Feather Touch focuser range too well but having consulted their website, I believe the model of focuser fitted to my scope is the FTF2025BCR:

    Feather Touch Rotatable 2.0" Diameter Dual Speed 2.5" DTT, Brake, Compression Ring (starlightinstruments.com)

    Looking at the focuser closely I can see why these things have the reputation that they do. I used to think that Moonlite focusers were pretty well put together but the Feather Touch takes things to another level of refinement. 

    I was a bit shocked to see the model that I have listed at one UK dealer (not FLO) at over £900 though. I thought that they were around £500 - has there been a price rise recently ?

    I know that some folks use the lightweight version of this focuser and also the 3 inch versions which are well over £1K on that basis, I would think.

    tmb130trex10.JPG.1ebb6381ddddde889c192da9082b94ca.JPG

    A couple of months back I picked up a pre-owned, but mint condition, Feather Touch micro pinion assembly for my Tak FC100-DL. That scope uses a 2.5 inch diameter focuser rather than the 2.7 inch that a number of other Tak models use so finding the correct pinion assembly can be tricky. When one popped up on UK AB&S at a fair price I thought it was worth a punt. There was nothing wrong with the stock Tak single speed R&P focuser in all honesty but now I have the Feather Touch pinion fitted and adjusted (which took a few tries to get right I ought to say) and I've taken the opportunity this evening to fine tune it's action to emulate as closely as possible that of the full Feather Touch on the 130mm refractor, I'm pleased with the upgrade. The 10:1 reduction ratio of the dual speed does seem to make finding that "best spot" of focus when using high magnifications on targets such as tight double stars just that little bit easier I feel.

    takFTug01.jpg.9ef2aa26a5ea84feb47af90c9e7acfa7.jpg

    In the past I've not been too fussy about focusers and have taken the line that if it moves the eyepiece in and out smoothly and holds it steady at focus withough shifting then that is enough for me. That is still generally true I guess but I can now also appreciate why these Feather Touch units are sought out for use with fine telescopes - they are beautifully designed and made things 🙂

    The Chinese made alternatives have come a long way as well though. I recently bought a nice little 70mm ED F/6 travel refractor and the 2 inch crayford fitted to that is really smooth and impressive - especially considering that the price of the whole scope was a little less than the Feather Touch micro pinion upgrade for my Tak !

     

    • Like 11
  11. This is from a review of the GSO made Meade Lightbridge 12 inch dated June 2006, by the late Tom Trusock:

    "....I’ve owned truss dobs for many years now, and collimation is typically a 5 minute process when everything works well. The Meade took me about an hour to get acceptable collimation the first time, and while it got easier with practice, I never did get down to the 5 minute mark. A close examination of the workings revealed why. Ultimately I discovered that the springs Meade uses simply weren’t strong enough to correctly support the weight of the 12” mirror. Since it wasn’t properly supported, it didn’t move as freely in the cell as it should have, collimation was a real pain, and exacting collimation was nearly impossible. Frankly, I’m not sure that I ever got to see the best images this mirror was capable of producing.

    New bolts and springs would be an improvement....."

     

     

     

    • Thanks 1
  12. Although they don't cost much and can be fitted relatively easily, when I see threads like this I can't help asking myself why such a basic upgrade is necessary to a simple component that is critical to the successful optical performance of an instrument ?

    With GSO newtonians (and maybe other brands) the need to upgrade the sub-par stock primary springs has been documented for many years by reviewers and yet we are still having to do it.

    Collimation is one of the big issues that can put people off newtonians - I would have hoped that by now manufacturers could at least install stable support for the primary so that, once achieved, collimation is maintained in a reasonable fashion. 

    This isn't a rant, just a rather puzzled and slightly exasperated comment 🤔

    In most other respects these scopes are excellent of course 🙂

     

     

    • Like 5
  13. I have an AZT6 which I use with an 70mm ED F/6 refractor which weighs 2.2kg. The mount seems to work well with that scope without a counterweight. Alt-az mounts can be very sensitive though and sometimes a relatively small increase in the length / weight of an OTA or it's balance can upset the smooth motions. The 70mm F/6 is the only scope I use with the AZT6. With the tripod the whole setup weighs just under 5kg which is really very portable.

     

    • Like 2
  14. It's quite milky here tonight so doubles rather than fainter far off stuff make more sense.

    I have spent a happy 20 minutes with my 4 inch Vixen on the Hercules globular clusters though including the one that I often overlook, NGC 6229.

    This one is much further away than M13 and M92 at around 100,000 light years hence it's fainter and smaller than it's more famous companion clusters. Worth finding though, between 42 and 52 Herculis. It is classed as one of the outer halo globular clusters which are the most distant objects associated with our galaxy.

    The age of NGC 6229 is given by several sources as a staggering 14 billion years old 😲

     

    • Like 8
  15. 57 minutes ago, Mr Spock said:

    Just had a look at Venus with the 4". A bit wobbly at x185 but the blue filter helps tease out a bit of cloud detail.

    Can't really tell at the moment as it's still light but transparency doesn't seem too bad at the moment so hopefully I'll get the doubles session in I'd planned for the other night.

    You have tempted me into popping my Vixen 4" out Michael 🙂

     

    • Like 1
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