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Piero

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Posts posted by Piero

  1. I have a N13T6 (my second, lesson learnt!) and also had a 12mm Delos in the past. Optically the Delos is a touch clearer and for this reason possibly more suitable for planetary observation. It's a medium size eyepiece though and for that size I found that I want more FOV from an eyepiece. The Nagler T6 is a very powerful little tool which fits in my eyepiece pouch nicely.

    My Delos 12mm was sold as replaced by the docter 12.5mm. If I didn't have the docter, rather than getting a Delos 12 I would get for a 13mm apm xwa.

    Note: I don't observe with spectacles and I tend to observe DSOs mostly.

    • Like 1
  2. In my 4" f7.4 I like the set: 24 Pan, 13-9-7 Nagler T6. The 3 naglers are then barlowed with the baader qturret or VIP. They offer plenty of FOV and don't affect the balance of the telescope.

    Other times, I use the set: 30mm, Zeiss zoom +/- VIP Barlow. That's my 2" set for that telescope. It's largely used when I feel lazy or for observing planets and the Sun.

  3. 15 minutes ago, josefk said:

    thanks @Paz - it's tricky not being able to thumb through it but i can imagine it from how you describe it. I may take the leap anyway (to use standalone) because i can still see a few copies available new and that situation is probably time limited (when its gone its gone).

    I have Sky Safari Pro so possibly do have all the info it provides but i prefer using books at the weekend after spending all week starting at a screen 🙂

    Cheers

    It contains a rich amount of tabular data. Descriptions are minimalistic and I agree that it works best when combined with the atlas rather than standalone. 

    It's a great guide.

    • Thanks 1
  4. My 12" was designed by Lukehurst. The original mirror and rocker boxes were quite tall and in my opinion the rocker was not particularly sturdy  although it worked. 

    I updated it quite a lot last year and now it's much sturdier, lighter, more portable, but most importantly more predictable in terms of performance particularly due to the new mirror cell.

    Here's a summary of the changes.

    12_f6_main_changes.thumb.jpg.17cbd04953ae1edb081482951e560243.jpg

  5. The rockerbox of my 12" f6 has a thickness of 3/4”. It works but I think it is better now after decreasing the centre of gravity.

    In my 16" f4 the boards have these thicknesses: bottom: 1", sides: 30mm, front/back: 15mm. I used dowel joints for the RB.

    Personally, I'd go for 3/4” for a 10" and then cut off wood without affecting sturdiness.

    IMG_20220529_135624_resize_4.thumb.jpg.167a8e590577f7db5b9750bced8d8a64.jpg

    • Like 3
  6. 1 hour ago, flyingdutch20 said:

    No proper first light yet, but yesterday it was dry for a couple of hours so took the opportunity to build it up completely.

    Note: beginners mistake, the eye piece is on the wrong side 🙂

    Movement is like butter - very happy with it.

    Put a 30mm eye piece in and found something just far enough to focus on - impressive. 

    Forecast for this week might give me a couple of hours under the stars one evening

    IMG_20230107_140656816.jpg

    Nice telescope, congratulations!

     

    Btw there isn't a right / wrong side of the focuser. Personally, I much prefer the focuser installed to the right when the telescope point to the south (like on your photo). In the north hemisphere, this means that the telescope is pulled towards the observer - which is a safety bonus if a ladder or step is used. If one is left eye dominant, it can also be easier to switch between focuser and finder.

    I fitted the focuser to the right side in both my 16" and 12" dobs for these reasons.

    • Like 3
  7. 15 hours ago, Ratlet said:

    Another winner for pretty telescope.  Lovely finish on the wood.  Reminds me of an old TV set.  

    Would rather a picture of this on my wall than a tak.

    I can satisfy your request Sir! :) 

    Here are the Google Photos albums. They show the building process from the most recent to the oldest photo:

    • Like 1
  8. 2 hours ago, F15Rules said:

    That chair is certainly a work of art, Piero!👍

    Do you wear a parachute when observing at the top of it?:glasses12::)

    Dave

    Thanks Dave :D 

    That's a good question actually! The chair was designed taller than necessary, so that a child with adult supervision can sit and observe. With the 16" f4 dob, an adult would sit at about half height when the telescope points to the zenith. With the 12" f6, the seat needs to be placed higher but I generally stand when observing with that dobson. In conclusion, yes, for an adult, the chair is taller than necessary. It is comfortable for the back though.

    • Thanks 1
  9. 2 hours ago, Ratlet said:

    Another winner for pretty telescope.  Lovely finish on the wood.  Reminds me of an old TV set.  

    Would rather a picture of this on my wall than a tak.

    Thank you.

    The second dob was finished with Ronseal yacht varnish. I finished the chair with Smith's CPES and Ronseal polyurethane. The finish was pretty and a bit easier to work with, so I applied it to the first dob too one year later.

  10. 15 hours ago, niallk said:

    I certainly consider them pretty ;)

    The 2nd one is all your own work, isn't it?  Beautiful job! (+on the observing chair too!)

    Thank you 🙂

    That's correct, the second dob and the chair were built from scratch.

    The first dob is a substantial redesign of a Lukehurst dob. Here's a summary of the changes side by side. Not sure how noticeable is, but the mirror box is quite shallow too now (15").

    12_f6_main_changes.thumb.jpg.3facdf5bb93a3a4a8108931394014128.jpg

    • Like 5
  11. 18 minutes ago, Louis D said:

    If you already swapped a Delos for an XWA, why haven't you swapped the 22mm NT4 for a 20mm XWA?  You'd have some extra cash in your pocket as well.

    I had a 20mm XWA in the past but decided to sell it as I tend to prefer a more comfortable eye relief at low powers. The 20mm XWA was also a bit soft at the edge and this is noticeable compared to the 9mm and shorter focal lengths whose edge is sharp. I find the N22T4 very comfortable and the AFOV presentation is similar to the docter, which is an outstanding ep in my opinion.

    With my 16" I don't need that extra FOV at low power, particularly considering that I tend to use 12.5mm or 9mm for finding targets anyway.

    The delos are fine eyepieces, but at ~230x, ~307x and ~415x a larger FOV helps, and the difference between 70 and 100/110 is massive.

    I can also use the APM XWA in 2" mode.  The same can be done with the delos using a baader pushfix adapter, but this adds extra weight to an already heavy-ish eyepiece for what it delivers.

    • Like 1
    • Thanks 1
  12. 2 hours ago, Andy ES said:

    Hey, this is great. It’s like going to confession with everyone “fessing up” to what the’ve really got.😳

    Especially when everyone tells you that you only need 3 eyepieces, Low, Medium & High power! 😂

    My meagre 7 are detailed below. I’m actually lying  about the ES 28mm though, as still waiting for it after placing an order 18 month ago.

    Enjoy your collections.

     

    3 eyepieces or 1 low power + zoom + barlow are the very minimum.

    However, when you have multiple scopes or the focal length is long enough, more eyepieces are needed to cover a wider range of targets.

    For instance, my 16" + pc2 has a focal length of 1868mm. I want something around 400x for PNs but also a low power for about 1 deg FOV (80-100x). Between these magnifications, I want 2-3 eyepieces to cover galaxies, globular clusters, small open clusters and planets (although the latter ones not my main targets).

    Another reason for having different types of eyepieces is the size / type. 100 deg eps are very handy for long focal lengths scopes, but these can be heavy and cause balancing issues with refractors (although the views can be breathtaking!). Naglers T6 are powerful but compact - an excellent compromise I'd say if eye relief is not an issue. I store mine in a pouch so that it is attached to my waist: no eyepiece case, pure grab and go. They are also parfocal, which is a great feature for my 12" f6 which now fits an helical focuser to slim down the UTA as much as I want to without affecting sturdiness. This eyepiece choice allowed me to reduce the size of telescope components, making it more manageable.

    In conclusion, there are many aspects to consider. That's why choosing eyepieces can be hard and a long going process - which inevitably affect the wallet!

    • Like 2
  13. In my previous post I should have added that those eyepieces are used with 5 telescopes as their focal ratios are not too different.

    To be explicit..

    In Italy I have a SW 8" f6 dob which is used with 25mm, 10mm plossls and 5mm ortho.

    In the UK:

    - TV60: 24 Pan, N9T6, Nikon mc1 zoom and baader q-barlow (1.25" set)

    - tak100 f7.4: 1) 24 Pan, N13T6, N9T6, N7T6, VIP Barlow (1.25" set); 2) 30mm APM UFF, Zeiss zoom, VIP Barlow (2" set)

    - 12" f6 dob: 24 Pan, N13T6, N9T6, N7T6 (1.25" parfocal set)

    - 16" f4 dob + pc2: N22T4, 12.5mm Docter, 9 7 and 4.8mm APM XWA (2" set)

     

    These are the eyepieces I use. Then I have 3 TV Delos (which have been dethroned by the APM XWA) and a broken TV 20mm Plossl which likely has the lenses reverted (I need to contact televue as I cannot take it apart due to cemented barrel).

    • Like 1
  14. Great report, Stu, and happy to read that the Moonlite CR2 works well!

    It happens to lose a bit of motivation in this hobby. It is not like reading a book on the sofa! It's a rather tough hobby, outside, often in damp conditions, in the night, equipment to lift, etc.. as you said though, the sky has unique wonders to show. To me, this and the direct interaction with nature are driving forces, which take me out when I can and feel like.

    I work mostly remotely and will hopefully continue doing so. That said, work has been literally crazy since Dec 2021, due to a tender (which was won, but forced me to work insane hours). In my free time, I bought a new house and moved into just a week ago. Finally, over the past few months I redesigned my 12" f6 whenever I had some spare time too. Despite all of this, my biggest problem is and remains insomnia, which does not allow me to recharge properly..

    Anyway, I only wanted to say that it happens to be busy and exhausted, but the sky is (and will still be) there, waiting for people like us. :)

     

    Regarding whether installing the focuser to the left or right in a Newtonian telescope, it's a personal preference.

    In my 16" and 12" dobs, the focuser was installed to the left when the telescope points to the South. The reasons are:

    1) I prefer to pull the telescope towards me, rather than push it away. (It is also safer with the 12" as I need a step to observe near the zenith with that telescope).

    2) I'm right hand and I use that hand to move the telescope. 

    3) I'm left eye and find it easier to move my head between focuser and finder, as well as turn my head to the Telrad/Rigel.

    My skywatcher 8" dob has the focuser on the other side instead. It's okay, of course, but I just find it easier when it is to the left.

    • Like 2
    • Thanks 1
  15. I'm not sure why you need a bag.

    For a small/medium dobson like that, I would simply put the rocker box in the boot and the tube on the back seats of your car. If you are worried about scratches on the metal tube, you could wrap it up with a blanket.

    In any case you will need to check the collimation before using the telescope and dust won't enter in the tube due to the front cap.

    • Like 2
    • Thanks 1
  16. 2 hours ago, Paz said:

    I use a telrad on big scopes and prefer a Rigel on small scopes. I wish though the Rigel came with a contraption to allow mounting on a universal shoe mount, it would be so much easier to use flexibly.

    (Scopes n stuff in the US do one but it's not worth the postage to order one on its own).

    The Rigel finder is quite light.

    You can simply drill and tap the shoe mount of the Rigel (where the screw would pass) so that you can install a bolt. Then you just need an aluminium plate and job done.

     

    Btw I use a telrad on my 16" and a Rigel on my 12". Originally, they were reversed, but while redesigning my 12" I decided to minimise the UTA weight as much as possible and so the two units were swapped. Between the two, I prefer the telrad, but the Rigel is a great alternative if weight is a concern.

    • Like 2
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