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About sophiecentaur

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    Star Forming

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  1. @vlaiv Thanks. That makes sense and I will try both positions. Aamof, with the existing layout, focus is only just possible by pulling out the tube past the detent position - not the best thing. It could also account for why the image I get is a bit larger than the image that Stellarium predicts.
  2. I use two extension tubes for connecting my DSLR and wanted to use my 2X barlow for a moon image. A field flattener position relative to the sensor plane is critical and I was wondering what difference it would make to fit the barlow right on the focuser or to fit it between the two extension tubes. It's a 2" barlow so balance could be an issue in some circumstances.
  3. Ye Gods. As simple as that!!!!? What a Durrbrain. And I found the Bayer problem too. Thankyou.
  4. Actually. I am now using an ED120. Also I am using the ZWO driver and selected that camera. The control sliders are very short and the trackpad is pretty rubbishy so it's hard to make fine adjustments. I normally use Apple stuff and the user interface this Dell with W7 running feels prehistoric.
  5. That's interesting. I don't think that theres a cat's chance of setting the exposure / gain to get that sort of range. I think I need another app for driving the ZWO - just to see if there's any difference. No chance of getting out there for a while, tho'.
  6. Layered composites - that would explain the moons problem. Too big a contrast range to deal with everything. I wondered about de-Bayering but I couldn't find the button. Well- I must have found it once 'cos I broke it in the first place! Thanks guys and I will contact Robin if I get no joy when I am next taking pictures.
  7. I think I must be doing something wrong, trying to drive my ASI 120 colour camera with sharp cap or with PHD. The display sometimes seems to show no stars at all until I increase the exposure or gain right up and then I just get a lot of noise. I can see Jupiter ok and the bands but its moons don't show up until the features on Jupiter are burned out. It seems as if the dynamic range of the sensor is narrow but that's not what people seem to be saying. Could it be something to do with the 5V the USB connection is giving the camera? Or is there a setting that I haven't yet spotted. Also, despite having managed to get a recognisable colour picture using Registax, I now get a monochrome rendition with a grid of dots. I have obvs, tinkered with a control and I can't seem to get back.
  8. I'm a bit of a newcomer to astronomy (i.e. actually owning telescopes) but I do see some amazing inconsistency in quality. A lot of attention is paid to the optics and I believe that is pretty good value because people are aware of that aspect of the subject. But I keep seeing instances where the mechanical ( and software ?) aspects aren't as convincing. People seem prepared to make allowances in that direction and blame themselves rather than the equipment. Only this afternoon, I was playing with the mount and Parked it a half a dozen times in the process. Each time, the Show position in the parked position seemed to get nearer and nearer to NCP. It finally told me it was at 90/360. What could have been going on there, I wonder? What could (should) have been changing? I think your idea of going back to Factory Settings is probably the right thing to do. I guess that the digital arithmetic may run out of precision and the errors can just add up. The processors in the Synscan are probably a bit limited and that could account for a lot. A raspberry pie would probably be a good replacement but we'd all end up paying through the nose for something as extreme as that.
  9. Haha - so much for fixed stars! I wouldn't insult you about your time entering skills?? The SW has that crazy US format option fixed which I can only have confidence in when the day is 13th or more. Last night I went out and set everything up carefully (with the 80mm ED) - except that I couldn't actually see polaris so I assumed alighment hadn't;t changed. iPhone levelled and az/el scales zeroed and weights down in the home position. Starting from Parked option. Show position gave declination of 89.9' (best I have ever seen) and some random RA number. It went directly to the first alignment star (right in the middle of my not too well set up Telrad) and the other stars were pretty easy to centre up on. Then the mist came in (Humidity 99%) and I couldn't even see the Moon. But at least I proved to myself that the system can work. I have no idea what has been going wrong. Perhaps there is some intermittent in the encoders. I will have to repeat things with the heavier Newtonian. Fun fun fun.
  10. I mean that, at some angles (of the mount) the clutch doesn't seem to hold the load but in others it does. (I can get a reasonable balance) I think I will have to remove the barrel and look at the bearing surface to see if it is scored in some places. I don't seem to have any problem when I hang my ED80 Equinox plus other kit on it. Whilst I was generally cleaning the mount up in an attempt to make balancing a smoother operation, I noticed another really poor bit of Skywatcher Engineering. The dovetail clamp has a fundamental flaw in its design. There is nothing inherently keeping the sliding part in place except the two adjusting bolts pressing on one side of the scope dovetail. Even the cheapest form of bench vise has some taper to keep the moving jaw from jumping out of line when the screw is turned. You tighten it up and the dovetail just jams into place. To release the dovetail to adjust its position, the bolts have tightened up and there's an inevitable clunk as the jam is released. There is no excuse for that. On the mount, there should be a dovetail to keep the clamp properly down on the bed. I guess it was designed by the same guy who decided to go for the peg and bendy bolt design for the azimuth adjustment on the wedge. These things are well over £1k and the mechanical design should reflect the price. I presume the (even) more expensive mounts do it properly but doing this properly involves no extra cost - just a bit of thought.
  11. They tighten or not, depending to the position - which could be worrying. But I will have to go out and look again, now that you have given me some input. If necessary, I can do the dismantling and re-assembly as I have done 'most things' on cars and electrical equipment. I avoid it these days unless there's no option. I find that some of the mechanical design quality in my astro equipment is really quite disappointing, compared with the Marine equipment that I coped with on my sailing cruiser. It was always expensive stuff, though - but so is a lot of the astro equipment. Not safety of life though!
  12. Thanks very much for those pictures. I now know what's inside that barrel without dismantling it all. If I remove the brass button I should be able to see the state of the brass barrel. One reason I suspect that it could be slippage here is that it was used for a long time by a previous owner with the 10" Newtonian plus a lot of other stuff on it and I already found that the Wedge Alt mechanism was really mangled. I have solved that problem with a mod which behaves very smoothly at 52 degrees of Latitude (That peg and bolt system really is the pits and the design must have been made and approved by someone resident much nearer the Equator). I could imagine that I will find some load related carnage when I take a look at the clutch. The design of that clutch is not impressive, though. Such a small area of contact for what has to be a pretty low mechanical advantage mechanism. I guess you could argue it limits the possible load on the worm but there are many better ways to achieve that. I have to admit that the s/s tripod is amazing. It sits on three slate pads and maintains polar alignment over weeks without attention - no need for a pier at my level of operation.
  13. I think I may have found the source of the problem. Going through the exercise this afternoon (Sun helps the brain a lot) I found that things go ok with the mount not loaded. I have a feeling that the problem is not software but hardware based and that it could be the clutches slipping with my very heavy 10" Newtonian. That could easily be introducing random offsets. I will have to investigate and perhaps clean up the clutch mechanisms. Is there any expertise in that direction around? Thanks for the contributions to this thread, everyone. It managed to convince me to look elsewhere for a solution.
  14. I don't find it hard work to polar align or to set the mount up with clutches released and using a level in the normal way to do the initial setting up. This is really not the issue. Whatever the accuracy of any alignment process, if I turn off the power then the mount cannot be sure what I have been doing with the clutches (they could even be left disengaged). Does it not have to assume it is starting from Home and that the display when I Show Position should show NCP co ordinates? It is a very simple question which I'm sure can be answered in isolation from all the other alignment questions. If, at the Home Position, the show position gives a value that's nothing remotely like the NCP, how can the mount have a chance of pointing any where near the first star in the star alignment process? Any other system for measuring anything at all, starts with the origin being set to a 'zero' position. This is true for a stop watch, a barometer or an oscilloscope so why doesn't this seem to apply on my mount? Also, why does no one else seem to have experienced (or considered) this sort of issue? Some of the posts above seem to imply that, even with the clutched disengaged, there are additional encoders that measure the position. That is even more confusing.
  15. I mean loose the clutches and move the mount to that position by hand. So the number I set into the position memory and the actual mount position should agree. Logically, when it's told to go to the Park position, the Show Position should be NCP plus or minus a little bit. PS I can't seem to get the four direction pads to get to NCP directly. They all interact in a way that I am sure they shouldn't but RA can be 'anything' at the Pole. The crosstalk between the two pairs of pads makes no sense to me at all.
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