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CraigT82

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Everything posted by CraigT82

  1. Quick update on this mod... Have swapped out the 2mm steel flat for some 2mm ally angle (asymmetric 20mm x 5mm). Much lighter and stiffer than the steel (which had started to rust before I got around to painting it). Also secured the 'sliding' ends of the ally to the OTA with a couple of screws for better rigidity but now I have to remove the two screws in order to collapse the tube, which to be fair I'll only really do when packing it up for holiday. I've had this setup out under the stars a couple of times now and I'm really pleased with it
  2. Yes I did, I should probably update that thread as I've actually had a chance to test out the mod in anger
  3. This is my travel set up... Heritage 130p ota, modified with 2" crayford focuser. On top of a Astropro 187 tripod ball head/ pan plate combo inspired by Fozzie! I must say the movement in alt and az is lovely and smooth but with about 4kg hanging off the side the tripod will tip over fairly easily. Saying that the more extended I have the legs the better it gets. Larger base area and all that. I could remove the tube rings and have the dovetail attached straight to the ota to shave a bit of weight off and reduce the lever arm by about an inch.
  4. Nice start! The baader 2.25x Barlow really is an excellent piece of kit.
  5. Thanks! I think the tube struts as they are are just about stiff enough to be used with my current EP's. If I wanted to use something like a 30mm ES82 I'd have some problems as they are weighty beasts, though saying that the struts can be stiffened up nicely by retracting them a couple of inches. The problem then is that you may get some light loss from the secondary as it could be too far forward to intercept all the light from the primary, plus you'd be bringing the edges of the secondary into play which may not be as flat as the center of the mirror. I haven't done any testing to see exactly at what point of retraction the light loss starts but I'm planning to do it. The secondary mirror was easy to realign, just loosen the central screw then turn it around ad re-collimate.
  6. Yes I wondered about that, I think I read somewhere that the field stop diameter is broadly similar to the focal length but I might be wrong. Actually thinking about it some more that's not quite right, as a 32mm plossl will have a much smaller field stop than a 31mm nagler. I do have a plastic vernier caliper at home which I could use to measure the actual diameter without risking scratching the glass I will report back once I've used it in anger!
  7. Thanks Stu, I did worry about that before starting out with the mod, but as far as I can tell it should be fine for use with longer FL EPs. The secondary is actually oversized by some margin, it's 40mm (31% CO). The image below show that with a 28mm EP there will be a 0.3 magnitude drop at the edges, which I think is acceptable (however I've only guessed at the 'diagonal to focal plane distance', I need to measure it and re-run the chart). I think with this F5 scope 28mm EPs are about as long as I'd go, my current 32mm panaview gives a 6.4mm exit pupil which is a bit too much.
  8. Thanks! There are still some issues with the mod that needs sorting out, the focuser drawtube is quite long as needs cutting down a bit as it intrudes into the lightpath when my EPs are at focus (the other option is to collapse the trusses an inch or two to shift the focal plane further out - but then I'd be worried about light loss from the secondary being too far forward). Also as the drawtube protudes into the OTA it prevents the trusses from collapsing fully, the last photo shows how much the focuser has to be wound out to allow the bottom of the drawtube to clear the OTA. I think for airline travel I'd remove the focuser and store it within the OTA with suitable foam padding and protection for the mirrors. Once I'm happy that the whole thing works, I'm going to cut off the original focuser and move the new focuser around to take up the original position, that's simply a matter of drilling 4 new holes for the ends of the steel strips to attach to the UTA.
  9. Hi all, been busy this afternoon adding a 2" Crayford to my heritage 130p. My idea is to turn it into wide field DSO travel scope for airline transport to very dark skies (I'm visiting Tasmania I'm January - very excited about super dark southern skies there). I've always thought it's a great little scope which punches about its weight, just let down by its primitive 1.25" focuser. I bought a TS 2" single speed Crayford to fit to the OTA, this particular focuser is relatively lightweight (500g) compared with other aftermarket crayfords which are closer to 1kg. The weight matters as the trusses will only take so much added before it begins to twist and flex (about 1.3kg by my testing before the collimation is affected). I can now use weighty 2" widefield EPs (up to 750g) with this scope, and with a bit more fettling it will be a superb travel scope.
  10. Swung by Maplins on the way home tonight and they had the swish grey cases on sale. Since it's payday I treated myself (and my EPs!).
  11. I've never seen tha Vixen HAL tripod in the flesh... Does it come with the wooden inserts at the bottom of the legs or is that something you've done? It's genius if it is!
  12. Why isn't there an 'opens can of worms' emoji?! I'm not sure there is such a thing as 'the best' EP. Only 'the best for you'.
  13. Looking good! What do you use to power your fans?
  14. My own modded 200p skyliner tube, on a poor old CG5 struggling under the weight. Note water bottle hanging off cw bar for extra weight. You also get an idea of the LP I have to battle!
  15. Here's my newly acquired Opticstar AR90S.... A nifty little 90mm f5.6 achro set up as a wide field companion to my skyliner on my skytee. Im actually quite impressed with this little Frac. I bought it purely ft widefield viewing with my ES68 34mm EP giving a 4.5 degree TFoV (and also to use as an airline portable travel scope) but I've jest been out checking it out on Jupiter with my 6.5mm Morpheus and it shows a good deal of detail, there's also plenty of CA as expected but not so much as to detract from the detail I feel.
  16. The dob base of the bresser also looks like it's been designed for disassembly, which would be good for storing/transporting the scope when space is tight. However, the sheer number of skyliner owners means that if you ever have a problem with it or need advice on modifications then there's plenty of people to offer help. The bresser is relatively new so not to many of them around. If you want to add the skyliner to an EQ mount you can pick up a pair of tube rings for £30-40 (plus another £30-40 ish for a dovetail)
  17. Nice job! That's a really professional looking finish you've managed there Any half decent scope really deserves a good focuser, it's such a critical part of the scope and so many new scopes ship with sub-par focusers its criminal really. But hey-ho... At least it leaves those of us who like to fettle, something to fettle with! (And synta scopes are ripe for a bit of self improvement as they usually are a bit shoddy but have good quality optics, which is what counts at the end of the day).
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