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Everything posted by rwg

  1. I suspect that these are 'USB Video Class' devices, so they don't need a specific driver on Windows - they will just pick up and use the Microsoft Webcam driver. Proprietary drivers like those for Altair/QHY/ZWO cameras will not work as those drivers are designed to talk to the special firmware code on the cameras of the same make. UVC devices appear in Windows as DirectShow webcams - this means that they suffer all the limitations of webcams such as limitations to how accurately you can control exposure (powers of 2), no access to high bit depth modes, no RAW mode, etc. If UVC has been done properly by the manufacturer then you should be able to control the exposure in powers of two - ie 1/16s, 1/8s, 1/4s, 1/2s, 1s, 2s, 4s, etc. This will appear as a standard exposure control in SharpCap or other programs capable of controlling webcams. Somewhere the manufacturer will have set limits on the min/max exposures, which will obviously limit the range available. cheers, Robin
  2. I guess you are using a webcam (DirectShow) driver for this camera - in which case your experiences with PHD2 aren't so surprising... PHD2 doesn't attempt to adjust the exposure length of webcams at all - if you set an exposure to (say) 1s, all it does is add up all the individual frames that the camera delivers in 1s and uses that mini stack as it's frame. That explains why it only spots the bright stars - the dim ones don't even show up at all in the 1/30s exposures (or whatever the default exposure length is) that are being stacked, so they don't show no matter how many frames you stack... If you are lucky then you will be able to adjust the exposure from the camera settings dialog (just to the right of the brain). The white frames are due to PHD stretching each individual frame as far as it can (which it does by default). When there are no bright pixels, that means a very large stretch is applied, giving the whiteout issue. cheers, Robin
  3. @Atreta until yesterday there was a donation button on the SharpCap web site. I've removed that because with the release of 3.0 in the next week or two there will be a 'Pro' option available for those who wish to support SharpCap. cheers, Robin
  4. If you are up for a good read then everything from SER file format to Altair camera controls is documented in the new SharpCap User Manual - http://docs.sharpcap.co.uk. cheers, Robin
  5. Ooops, copy-and-paste error on the link... fixed now. One of the things on my to-do list post 3.0 is what I'll call 'Dynamic ROI' for now - this is for high speed planetary imaging and it will automatically move the ROI around to keep the planet in the ROI region (but no mount guiding). Actually guiding the mount for planetary/solar/lunar/live stacking will follow on from that. cheers, Robin
  6. Just an update to say that there is now a SharpCap User Manual available - you can find it here http://docs.sharpcap.co.uk/2.9/ I want to say thank you to the SharpCap users who have helped get this manual written - particularly DavidR(@turfpit) who has spent countless hours on the project and without whom the manual would certainly not exist today! I am posting fewer updates here about SharpCap new releases, but they are still happening. To keep up with SharpCap news and updates, you could follow SharpCap on Facebook at https://www.facebook.com/sharpcap/. The best place to get support for SharpCap is now the SharpCap Forums at http://forums.sharpcap.co.uk. (Hopefully the admins will forgive me for including that link just the once!) The reason for a dedicated forums site is to try to reduce the amount of time I spend answering questions and therefore increase the amount of time spent writing new features! Having questions spread across this site, various other forums and Facebook meant I would end up answering the same question more than once. There will very shortly (next few days) be a new release of SharpCap 2.9 which will include the user manual and have numerous bug fixes. The release of SharpCap 3.0 will also happen soon - probably within the next couple of weeks. SharpCap 3 contains a whole range of new features including improved focus assistance, live flat frame correction, improved polar alignment, plate solving and much more. cheers, Robin
  7. Hi @Atreta, you need to be able to see the region around the pole (north or south) for the polar alignment to be able to work. I have an idea for a version that will work without seeing the pole, but have had no time to even test out whether it works yet, so it's a far while off even if it does work. cheers, Robin
  8. The solve status for the most recent frame is there - in Stage 1 and Stage 3 it's to the right near the 'Next' button and in Stage 2 it's to the left (I think that was the only space for it in stage 2). The actual plate solving procedure is fairly quick (fraction of a second usually) as it works over such a limited area of sky. Actually the first solve can take a few seconds as it builds it's search index at that point, but subsequent ones are fast. Anyway, as soon as the exposure finishes the frame gets passed to the plate solver and only when that is done does it get displayed on screen - if you see only stars on a frame and no NCP circles then that means the frame has already failed to solve, not that it's waiting for the solver to run. cheers, Robin
  9. @frugal Are you using the 2.10 beta? That has improved star detection and more tweaks to it too - it seems to have fixed issues in 2.9 with faint stars not working well for a number of people, particularly with lodestar cameras which seem to have no gain control Set a digital gain of 2x if you have no camera gain control and see if that helps. With a camera gain control (QHY, ZWO, Altair, etc) I'd usually advise exposures in the 1-4s range and a high gain. cheers, Robin PS. Don't forget to use the trial license key with the latest versions of the beta to unlock the adjustment phase!
  10. Personally I've never tried PE correction and just relied on guiding. cheers, Robin
  11. Look at the PHD guide logs - if it's mostly RA corrections then it's almost certainly periodic error. Polar misalignment would show up as DEC drift being corrected. cheers, Robin
  12. Are you sure that isn't periodic error? Two reasons I suspect this - 1) the trails are stronger at each end, suggesting it's spending longer with the star near the end than with it in the middle of the trail - that doesn't fit with a PA problem which should be a straight line 2) The trails look like they are almost due E-W (see http://nova.astrometry.net/user_images/1569527#annotated ) so it looks like you are getting trailing in RA, not DEC. Again this doesn't fit with a polar alignment issue, but does with periodic drive error. cheers, Robin
  13. Ah, good point - I didn't think of the auto-upgrade path when putting the license on the download page. I *think* I put something in the release notes that you see when you install a new version of SharpCap, but very few people read those I suspect... cheers, Robin
  14. If you look on the beta download page there is a license that you can use with the beta for now. This will continue to be available and updated during the beta period. So yes, you can still use the features for the beta period, but we've got to the point that the license entry/checking code needed to be turned on to make sure it didn't have bugs in it! cheers, Robin
  15. PHD does a strong stretch on every frame before displaying it which can make it's brightness onscreen misleading. There is a way to turn this off somewhere in PHD, but can't recall where. cheers, Robin
  16. @al-alami Have you turned up the gain? That's usually necessary to see a decent selection of stars with 2-3 second exposures. cheers, Robin
  17. Other possible causes of error that I am aware of * Bad plate solve on either the first or second stage - this could throw out the whole process - I think this is very unlikely and haven't encountered a case yet * Atmospheric refraction - only significant below 30 degrees of latitude, probably not going to be a problem in NE Essex! I would advise that if you are having problems, then at the end of the PA process (once adjustment complete), spin the RA axis again and watch the screen - the stars in view should appear to move around the point marked as the NCP. If none of this helps, then I am (for now) baffled. It would be helpful to have an image captured (saved using the snapshot button in SharpCap, not a screen grab) for each orientation of the PA process and also if possible an estimate of the PA error from an independent measurement such as PHD drift alignment. cheers, Robin
  18. One case where there was a similar problem was tracked down to a mechanical problem causing the view to shift as the scope is rotated - this led to inaccurate results. The user's view of polaris as they rotated the mount was like this As you can see at a certain point in RA, something shifted which then ruins the calculation of where the telescope's axis is pointing. Another (unconfirmed so far) suspicion is that there may be flexure in some mounts due to weight distribution changes when moving the telescope from the pole pointing position used for alignment to a more ordinary position for imaging. This might be a particular problem if you are using a tripod on soft ground. cheers, Robin
  19. Hi Sean, only supported in the 2.10 beta builds, not in 2.9 or earlier versions. If it's still not working when you try 2.10 please let me know. cheers, Robin
  20. Could it be that you have this option checked in DSS? that would turn your FITS files colour as DSS loads them. Still not sure about the spidersweb pattern. cheers, Robin
  21. Weird that all of your sample images have colour in them when you have the mono (1600MM) camera. Is Apt perhaps somehow treating the mono image as RAW? (but then I'd still not expect to see colour!). I'd suggest testing with another application (I can say for sure that SharpCap works well with the 1600 cameras ) to rule out software problems. Could the top image be the effect of some sort of contamination on the sensor? It would seem unlikely in a practically new camera but I can't think what else it looks like. cheers, Robin
  22. @Crose01 I think it ought to work - a side offset of a few inches (or feet for that matter) isn't going to make any difference as the stars are effectively infinitely far away... @spillage 2.10 (in beta) is better at picking up faint stars than 2.9, also there are tweaks to the star detection parameters that may help. Much more info here. cheers, Robin
  23. Hmm, once you have polar aligned with SharpCap, you have your mount axis well aligned with the pole. If you then set the correct orientation of the polar scope and then adjust the polar scope collimation to put Polaris in the circle I would have thought that you have then successfully aligned the polar scope correctly with the mount. Was that what you were thinking of? cheers, Robin
  24. Welcome, and if you haven't already pop along to one of the Abingdon Astronomical Society meetings - they are usually quite good, although I must admit to not getting along very often this last few months. cheers, Robin
  25. How about some of these? http://www.astrophotographycourses.co.uk/courselist.html Robin
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