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Ricochet

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About Ricochet

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  1. 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!).
  2. 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.
  3. Are you collimating the secondary using your Cheshire first? If you ignore the reflection of the primary and just look at the secondary it is too low. You can raise it using the secondary collimation screws but if the second step of aligning it with the primary takes it back to that same position then I think you need to adjust the spider vane lengths. Of course, that assumes that the laser is accurate. I bought a Hotech but found that the self centring was not consistent and I could not get repeatable results with it. These days I just use a Cheshire and collimation cap as the batteries in my cheap laser (for barlowed laser method) need replacing.
  4. This is not right. I believe that the stalk is threaded both ends and just screws into both the secondary holder and the side of the telescope tube. Check when the secondary support swivels if it is turning on the stalk or if the stalk itself is actually rotating as well so that you know which joint is faulty. Once you have determined that, turn the loose part to tighten it up. If you can get one full rotation you may be fine, but if it is always loose in the correct orientation then I would suggest going back to your retailer and see what solution they suggest (probably replacement). Edit: looking at photos down the barrel of the H130p it appears there is a nut where the stalk enters the tube side wall. If this nut is not fixed to the wall of the tube as the mounting point then it is a lock nut and you should tighten the nut to stop the stalk from turning.
  5. This is almost exactly what I do for DSOs with my 8" f6 dob. 28mm Nirvana, 14mm and 10mm XWs and a 2X Focal extender. Planetary is a different matter because then it's time for a binoviewer and pairs of small eyepieces.
  6. Alternatively, the Celestron X-cell LX/Meade HD60 ranges are pretty similar to the BSTs if any turn up on the second hand market. There are also the Baader BCOs in a similar price bracket, which are better optically at the expense of field of view and eye relief.
  7. This is correct. For visual use the barlow goes in the focuser and then an eyepiece goes into the barlow. This will double the magnification that you get from the eyepiece. For example the 25 mm eyepiece normally gives 1200 / 25 = 48X magnification. With the barlow added you will get 2 x 1200 / 25 = 96X magnification. This will be most obvious on planets and the moon. Stars are point sources so they will never appear any larger, but the space between stars will increase. With regards to better eyepieces for visual use the previously mentioned BST Starguiders are a good choice at a relatively low cost. If you just want to get some quick snaps of the brighter objects that you can see through your eyepiece then you will probably have more luck with a mobile phone camera. To use the Canon you would have to find a way of mounting it so that the end of the camera lens is the same distance above the eyepiece as your eye would be. If you are actually more interested in serious astrophotography then you will likely have to buy a new mount, telescope and camera as visual and photographic setups have different requirements. That is not how you unscrew the lens cell from the barlow. The black part that you show still attached to the silver part is the part that should be unscrewed. Once that part has been removed it can be screwed into the bottom of an eyepiece for approximately a 1.5X increase in magnification.
  8. What sort of budget are you thinking of? If you are looking for second hand equipment then the best place to look is the classifieds section on this website. Alternative places to buy second hand directly from other astronomers are Astrobuysell , ebay and some Facebook groups, but you will have to be more careful with those places. There are also a few of the established astro retailers who have started dealing in second hand equipment, but you will pay higher prices for the security of buying from a business.
  9. In my experience a neodymium filter is absolutely useless on DSOs but the filter to use for lunar and planetary viewing. The only light pollution filter I have used that is useful on DSOs is the Astronomik CLS, but this will probably become less effective as LED lights become more common. There is a new (ish) IDAS light pollution filter designed for use under LED lighting that might be useful, even though it is targeted more at photographic rather than visual use.
  10. No chance. The type of thing you describe is usually caused by water vapour. The possibilities that I would look at are: Observing when it looks clear but there is actually a layer of high cloud and/or general water vapour in the atmosphere. (Judging from clear outside this will be the case on 3/7 days this week) Dew forming on the eyepiece Poor coatings on a cheap eyepiece A low quality filter Internal reflections from the side wall of an extension tube/barlow/eyepiece Light scatter from the mirror edge
  11. A 3X barlow is unlikely to be of much use in such a long focal length scope. A 2x option, such as the Explore Scientific 2x Focal Extender is a good choice, but it depends what your budget is. However, given that you only just got the telescope I would start by just using the eyepieces that came with it for a while before looking at other eyepiece options rather than a barlow. More magnification is not always better and many new users try to push beyond the limits that either their scope or atmospheric conditions allow. You're probably not going to need anything shorter than about 5mm with that scope and for DSO viewing an eyepiece around 10-12mm is probably going to be the most useful, as well as longer focal lengths for objects that require a wider field of view and/or filtered nebulae. To give suggestions we really need to have an idea of budget and whether you need to observe wearing glasses. You haven't mentioned collimation tools, but I would suggest investing in a good quality Cheshire/sight tube and learning how to use it.
  12. Nice one John. The focuser baseplate has 4 little hex screws around the perimeter (2x 1.5mm and 2x 2mm I think). If you loosen those off you can rotate the focuser 45° so that it is in a better position no matter the altitude you're using it at. Also, I always use those big round holes in the base as handles.
  13. I think your most expensive eyepiece should probably be the one you use the most, so I would start with the 16mm.
  14. You want to get it so that everything is circular and everything except the secondary shadow is centred under the crosshairs. I would give it another go tomorrow and see if you can improve.
  15. Yes, it is the difference between the mirror temperature and the air temperature that causes the problems. I think a fan should work both ways, in that when the air is warmer it will help warm the mirror and when the air is colder it will help cool the mirror. Perhaps you can get better results simply by not using the ac in the car on your drive to the observing site (if that is bearable for any people in the car).
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