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kens

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  1. And/or use the Z-filter algorithm which lets you adjust the guiding response as a multiple of the exposure time (or, more correctly, a multiple of the sampling rate). But it is best suited to mounts that can make small, precise corrections.
  2. PHD2 operates the ZWO cameras in single shot mode rather than in video mode. The single shot mode has a latency per shot of a few hundred milliseconds (up to 500 from memory). This is a function of the hardware and ZWO driver. So if you choose a 1s exposure then the time between shots is going to be 1.5 seconds. On top of that you add the time taken to make corrections as you dont want to take a guide image while the mount is moving (and probably why single shot mode is used) and any download time. In my setup I can just get a 1s sampling rate if I choose an exposure time of 0.5 seonds.
  3. Avalon make a guide scope extender but its a bit pricey https://www.avalon-instruments.com/products-menu/accessories/extender-for-finder-guide-scope-detail
  4. One possibility: As you know the PA error can be broken down into an Alt and Az related component with the Alt component dominating near the horizon and the Az compnent dominating near the meridian. If one causes drift south and the other north then in between there is a crossover point where there is little or not drift. With the mount rotating you will encounter that point somewhere during the evening.
  5. Also tell us where your scope was pointing when you di the calibration. If it was in the home position pointing near the pole then you wont get enough movement in RA for the calibration to work. You should also try the manual guiding tool to check that the mount is actually responding to guide commands. To do this, point near the celestial equator and select a star. Then choose the Manual Guide option on the Tools menu. Use the maximum pulse duration (5000 ms) and click the west button. You should see the star move steadily on the screen for 5 seconds. Click East and you should see it move the other way for 5 seconds.
  6. Just FYI, the ASIAir is basically a Raspberry Pi and you can install Astroberry, StellarMate or a DIY INDI/Ekos/KStars onto it. These are open source are not restricted to ZWO hardware and there is even an INDI driver that lets you continue to use the ASIAir power ports. Plus you get the fulll blown versions if these and PHD2 rather than the de-featured versions implemented by ZWO.
  7. Have you got PHDLogViewer installed? If not you can download it https://adgsoftware.com/phd2utils/ The first thing I noticed is that your guide rates are set at the EQMOD defualt of 0.1x sidereal (or 1.5"/s) which is way too slow. Incerase the guide rate to somewhere between 0.5x and 0.9x sidereal. You will need to recalculate the calibration step size as a result. The other thing to check is the focal length of your guide scope. It has been entered as 50mm but I think that is the aperture, not the focal length. As a result, your guide RMS in arcseconds would be way off. The guiding RMS of 0.3 pixels is quite reasonable. Overall, I would suggest that you sort out the guide rate and guide scope focal length and create a new profile in PHD2 with the wizard. Then try again.
  8. Quite right. Should have had my morning coffee before responding 😬
  9. Then I'd suggest to use the profile wizard to create a new profile. When it is finished check the calibration step size on the Guiding tab of the brain. It should be around 400ms for a target around dec 0. In the calculatoryou need to enter the declination for each target as that adjusts the step size accordingly.
  10. Well I guess now, nobody is going to be game to recommend a HEQ5 to this guy 🤣
  11. It wont make any difference in your images. PHD2 works on pixel measurements and the focal length is only used to convert that to arcseconds for display purposes. Increasing the focal length value will make your guiding appear worse (assuming identical circumstances) as the longer length translates the pixel RMS value to a larger displayed arcsecond RMS value
  12. Your problem looks more like dec backlash. Your calibration is also not great. Did you calibrate on your target? The rates indicate not but that could be due to any number of things. The dec rate vs RA rate indicate calibration at a declination of around 33 degrees A good calibration is essential for guiding. Yours is orthogonal (good) but based on only a few data points. Ideally you want about 10-15 points along each leg. That is determined mainly by the calibration step size. If you use the profile wizard to set things up it normally calculates the step size correctly as long as you input the correct guide rate. If you didn't use the wizerd then set up a new profile using it and try again. Otherwise, recalculate the step size in the brain. You should be using a step size of around 400ms (vs 1200ms) to get a reaonable number of calibration steps. A reasonably good polar alignment is also needed for calibration but I don't see the telltale signs of very poor polar alignment in your calibration (a vee shaped RA calibration leg). Since you have both Astroberry and PHD2 you can ditch the polar scope and use any of the excellent PA methods in those tools. As a starter I'd suggest using the Polar Drift Alignment (PDA) in PHD2 as it is quick and easy. The EKOS PA too in Astroberry is also very good and more accurate but a little more involved. Both are easier and more accurate than using a polar scope and do not rely on a good calibration to work. After you calibrate then run the PHD2 Guiding Assistant including the backlash measurement. That will tell you more about what is going on.
  13. Could it be due to misting of the sensor cover? Would that behave like a giant dust mote?
  14. You may need to turn on debugging and capture the full logs for both camera and focuser. On your screen shot the message says "image received" which means an image was acquired - at least when you did your screen shot And tangentially, why is the focuser reporting a temperature of 33C in Canada in winter!
  15. Its so long since I used setting circles that I forget. And it might depend on the type of mount. But use whatever gives the right result. Namely, if you rotate the mount from east to west the pointer mark should point at decreasing RA values. Note that if you use the HA technique, that HA increases from east to west.
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