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sophiecentaur

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About sophiecentaur

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    Nebula

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    Male
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    Baking
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    UK
  1. eBay advertises a number of these eyepieces at just over £20 from China. That's half the cost of the cheapest obtainable elsewhere. IS it really worth spending out on a good quality EP if you don't want to spend your time looking at stars with a red cross in there too. (I think I partly answered my own question because, with the illumination off, you don't see the cross easily.) The question remains as to how accurate the placement of the cross hair needs to be - as long as it's consistent.
  2. Getting a solar image in focus

    Thanks. That is useful information. Next time it's sunny and I have time, I will have an interesting time with the more straightforward things that have been suggested.
  3. Getting a solar image in focus

    I can see some jerkiness in the live view mode so that could certainly be relevant. I will try alternative modes during focussing. Where would I get a "chipped adaptor"? Also how much would it be? Sounds like an expensive, one-off device to make the camera think it was using an f8 stop. The camera knows when it has no focal length info - you have to enter that in at switch on. There is also a control for lenses with no aperture control ("Aperture ring" setting) so I would imagine that one could use a false aperture lever which is what the camera uses with non-auto lenses. A clever bit of machining could be needed there. Possible, unlike the electronic solution, but beyond me, I think. I still might try a cut out temporary stop for focussing, though. But what do astro cameras do about this problem? Is there software control, perhaps?
  4. Getting a solar image in focus

    The ED80 is a fixed aperture and the only way to 'underexpose' is to use the minimum ISO (100), which of course I did. A proper exposure time gives me a good saved image but it's the situation with the sensor exposed during live view that gives the problem. I would guess that I could either use another filter (I did try adding my Moon filter, which is 13% neutral) but that was not enough. Perhaps a cardboard circle would give me a few stops down - say f16 - but then the focal depth is less critical. I have to 'apologise' that I want to do this without too much investment in solar imaging - it's obviously not a problem if very narrowband (and unbelievably expensive) filters are used as they only let in a smidgen of light in the first place. Perhaps stopping down would be the best way and I don't think there would be a diffraction limit at f22 or so. Thanks. I will try playing with that but the displayed image really looks burned out as if it's just too much light landing on the sensor. Needless to say, it's cloudy all day . . . . .
  5. I really did try a search for this info but it was beyond me! I have been viewing some really impressive sunspots with a simple Baader (silver) solar filter. My 80ED scope gives brilliant results and the spots are really crisp even with a 4.7mm EP. However, when I try to image it with my DSLR, the live view image just burns out and I can't get a convincing focus. With a 1/200 exposure through the filter, the pictures are not bad but I needed to use a suck it and see / repetition and chose best of the possible focus settings . That's obviously not satisfactory. Is the only answer to use an even heavier filter or to stop down the 80mm aperture? I guess you'll say I should get on my knees and focus through the viewer but it is so much easier to use my tiltable view screen. Also, if I were to use an astro camera, I wouldn't have that option.
  6. NEQ6 Elevation Manual Adjustment

    I am in the middle of this situation and it seems that different people have had very different experiences. My second hand mount has been used with quite a heavy load and I think this is to blame for what has happened to me. People seem to blame ham fistedness and not using the two bolts properly but I don't think that's always fair. My North bolt hole has just distorted so that the bolt points downward a tiny bit; enough th be skidding across the face of the lug and off the end at around 48 degrees setting. Not surprising as there is a immense length of overhanging bolt, supported in about 1 cm of hole depth. Neither bolt nor casting material were designed for that amount of torque. I am working on a form of cuboidal 'follower' (as in cam-follower) to support the far end of the bolt and transfer force to the right place on the lug. It worked with a crude wooden model and I have ordered some steel for a stronger version. At least that will transfer the force as pressure on the floor of the casting and spread force over the lug face. A couple of problems that will need to be solved. The profile of the face of the follower needs to be thought about and I will need a method of keeping the follower in place if the counter-acting bolt is loosened too much and the lug moves away.
  7. NEQ6 Elevation Manual Adjustment

    Upgrading would be an attractive solution if I could do it for an attractive price. There are a couple of mods which I have found and they effectively bring the angle at which the south side bolt engages to more like perpendicular. It limits the range of latitudes that it can be used at but that's not a problem. I have the thing in pieces now and it is a sorry sight. When I think of the many ways such a control could have been achieved I really can't understand why they didn't find a better one. It does worry me about the potential for finding more lunatic problems with the NEQ6. I guess a decent worm / gear drive would have added a few of hundred quid to the cost. For the want of a nail, a shoe was lost etc.
  8. NEQ6 Elevation Manual Adjustment

    The "thing to have gone" is the face of the 'peg' that the bolts push on. I notice you are in Portugal and that could well mean that you have a different experience of the mechanism. I took it apart this afternoon and - The first thing was a broken piece of bolt that hadn't been taken out. The previous owner had obviously not removed the mount and shaken it because the length of thread just fell out when I moved the Elevation. The second thing was severe graunching of the peg; so much so that the bottom edge was chopped away and the bolt passed through the resulting groove and had no effect at my latitude at 40N the thing works ok but 51N is too far for reasonable operation, apparently. The bolt is almost at a tangent to the peg end! Anyway, I shall order one of those pretty anodised gizmos and fit it. I have ground the bolts so that they have rounded ends. The rough put ends were very savage as bearing surfaces. (More bad design) Henceforth, it will get treated with respect and last for ever. - till the next thing falls apart.
  9. NEQ6 Elevation Manual Adjustment

    Thanks for the replies. The Astro-Babt link is good for the RA and Declination mechanisms but not for the Alt/Az system, unfortunately. I have found pictures of what it's like inside the mount and it really isn't a very good engineering design. It's particularly true for UK latitudes because the design pushes laterally against the North screw, causing severe graunching of the heavy 'peg' that controls the altitude, over time. The mount was second hand and the damage was already there when I bought it because it was very stiff and there was a replacement hex bolt for the South end. Its really is a shocking bit of design, to say the mount is a favourite for so many users. There are a couple of mods available, I have found, that basically shift the problem from high latitudes to low latitudes. The naffest motor car would not have such a poor mechanism for steering or tracking. No excuse at all for it. That's an interesting comment - what's it based on? The seller gives them an excellent write up. (Haha)
  10. The polar alignment elevation adjustment on my s/h Skywatcher NEQ6 is very stiff and the 'rear' bolt seems to have become 'bent'. I would like to get inside and see what's wrong. I have tried to get hold of a workshop manual but the ebook source I tried didn't turn out to have it, despite advertising it. They also stung me for a short membership fee. (I kicked up a fuss and they are refunding me in full - yesss.) I imagine it should be possible to remove the black side-discs on the casting but I don't want to scratch or graunch it. Has anyone done this job? Life is bad enough when I try to do a polar alignment without having to struggle with stiffness in the works. PS I have looked for the Astro Baby link, which would probably have what I need but the links seem to be dead. Any ideas?
  11. Polar Alignment on static pier

    The arrangement of four parallel bolts does rely on the shear strength of the bolts and their holes through the plates. It looks relatively easy (?) to shorten them. The bolts appear to be threaded along their whole length - in particular as they go through the holes in the bottom plate. That arrangement may not be as strong as it looks and they could perhaps be rocking slightly and there is no inherent strength in a parallelogram. Some very fat rigid washers on either side of the holes could perhaps help or a thick block between the plates to reduce the angle change if there is horizontal movement.
  12. How do you see screen in warm room??

    If you already have a mains route out there why not just run a Cat5 Ethernet cable out there alongside it? A cheaper solution and Ethernet travels quite well compared with USB (which was a 'Bus' system for connecting peripherals together locally and not really as long distance data link). USB can be a good solution in some cases, though - as is wireless.
  13. Best way to Barlow DSLR on 200P

    I realise that results will be limited but I should be able to get at least something better than I have managed so far. I take your point about the Bayer matrix but the element size is around 4 microns, which is not too glubby. There is no anti alias filter either; the sensor is jiggled around if you have moire problems. And, of course, once I am hooked on Imaging, my spending priorities may change and who knows what I will 'have to' buy.
  14. Best way to Barlow DSLR on 200P

    Thanks for the response. My dslr is 20Mps and the sensor is half frame. I don't understand how a webcam would do better than that. Have I missed something? The camera is a pretty new design; no change to the filtering on it though as I want to happy snap the family too. I wasn't planning on imagining faint DSOs at high magnification - just what should be attainable with an 80/500 scope. (According to what I have found on SGL etc.) I have no problem with planning to spend money on advanced things, once I have seen the inadequacies of what I have and the DSLR has produced some very nice images of 'easy' stuff so far. Problem about other cameras is that I don't use a laptop and I use Apple computing stuff. Bit of a double whammy at present.
  15. Best way to Barlow DSLR on 200P

    I have been trying to get pictures of Jupiter with my DSLR. Not big enough with my 800mm refractor and X2 barlow. From what I am reading, the idea of eyepiece projection seems to be out of fashion. It's even worse in my case because I only have 2" eyepieces and the hardware doesn't seems to be obtainable except at huge cost. So I need a more powerful barlow (x5) which would fill the sensor better. The question is whether to buy a much cheaper X5 1.25" barlow or a 2" X5. With a 1.25" I would need a different T Ring adaptor for that - but they aren't too expensive - and couldn't use my 2" eyepieces. Also, the Powermates seem to be highly recommended but pricey. Any opinions about that?
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