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Ricochet

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About Ricochet

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    Hertfordshire
  1. Which 130p? If it is one with a 1.25" only focuser then I would start over budget with a 24mm ES68 to max out the field of view. The shorter lengths he can save a bit on by going with Starguiders, BCOs or SLVs while FLO have them on offer.
  2. Easier to put a star in the centre of the FoV and time how long it takes to drift to the edge. Do it a few times in mono view and a few times inserted into the binoviewer/barlow and then divide one average by the other to get the multiplication factor. So long as there is no vignetting of course.
  3. You were out of focus and essentially looking at the inside of your telescope. Always focus your telescope to make the object as small as possible. For your telescope I would guess that actually a 10mm is about optimum for planetary observation. A Baader Classic Ortho would be a good and relatively cheap upgrade over the kit lens, if you don't need glasses and can put up with the short eye relief.
  4. Your current dob has a large radius of curvature so the combined fc might be acceptable. I've got a 14XW and 8" dob that are ok together, but focusing slightly off centre does help. However, if the Tak you are possibly getting is a doublet then it will have a very small radius of curvature and the combined fc will be higher. I would estimate that approximately 99% of the people who complain about fc in the 14/20mm XWs are trying to use them in doublet fracs.
  5. Is that all of the SLVs? I thought that was supposed to be an issue in early examples, but later corrected.
  6. Rotate the Cheshire in the draw tube and see if the crosshairs are centred on the doughnut at all angles.
  7. You say "we" so does that mean your husband is in on it or is it a surprise? Could you visit a local telescope retailer or astronomy society to look at a variety of telescopes and get an idea of what sort of instrument he could manage? A 130mm Newtonian or 127mm Maksutov on an alt-az (not eq!) mount would be my initial suggestions. With regards to brands you can't just go by brand name as the major brands produce everything from excellent to terrible. You have to look for feedback and advice on the specific model or line of telescopes that you are considering.
  8. What has not been pointed out is that the response of the eye to light intensity is not linear. In fact you have to double or halve the light in order to even notice the difference, so while technically a binoviewer halves the light to your eye, as far as the eye/brain is concerned the drop in brightness is only "1". This is the exact same reduction in brightness as changing from a 14mm to a 10mm eyepiece, for example, and I don't think there are many people advocating only ever using one length of eyepiece. For lunar and planetary observation where the objects are very bright to begin with, a small drop of light is not going to be an issue anyway. In addition, there are the advantages of binocular summation. From wikipedia:
  9. That is correct. Really you should adjust the centre screw, which pulls on the mirror, and the outer screws, which push on the mirror, sequentially so that it does not rotate. As you have found it is sometimes easier to hold the secondary support with your hand, but you must be sure not to touch the mirror itself. You should get the secondary support centred as a starting point. The offset should be built into the support and not something you need to worry about. Align the Cheshire cross with the mark on the primary mirror. Not true. If the orientation of the Cheshire makes a difference the Cheshire is faulty and should be binned. The only consideration is to angle the face so that it reflects a suitable amount of light.
  10. This is wrong. The centre screw determines the "height" of the mirror up and down the tube. If you have twisted the screw to turn the mirror then it is most likely no longer facing the focuser properly. Once you have the height set using the centre screw you use the three outer screws to make the secondary appear circular.
  11. I've not used it but I would expect it to perform quite badly. Wide angle eyepieces require lots of elements to get good correction at low focal ratios and using 2" glass the cost adds up quickly. You might find that quite a proportion of the field is lost to distortions.
  12. They've always been very good when I've used them, both in the shop and online. I've had a couple of issues with equipment failing and they were very quick to sort replacements.
  13. I think that the instructions for the Baader wonder fluid do actually say that you can use it for cleaning mirrors, but the suggested method is to entirely submerge the mirror in the fluid. Cost wise it would probably be cheaper to buy a new mirror/scope.
  14. Contact Bresser. They have a good warranty department and are quite likely to fix the focuser if you let them know you have a problem (and the receipts!).
  15. I believe there is a decent 60mm in the classifieds. As to the original question of what defines a serious telescope I have three proposals to be argued over discussed: A telescope sold by a "proper" astro retailer rather than by department stores. A telescope packaged in a brown cardboard box (or several brown cardboard boxes) A telescope not bundled with a 3X barlow and SR4 eyepiece.
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