michael8554

If it's not on your Flats, it is on the lens or sensor. Is your mod Ha or Full Spectrum ? If Ha, then the #LPF-1 I.R. and Sensor Cleaning filter remains, so you can't clean the sensor, only the filter. Did you clean with a puffer, or with the Sensor cleaning function ? As Peter suggested a daytime AV image of a plain background with the stock 18-55mm should eliminate the Samyung. Michael

Hi Robin In the second image it looks like a dewdrop that has slid down from top right to bottom right. So might have been gone when you did your Flats - why don't you post a Flat ? Michael

I think that PHD2 will show the Dec error line even with Dec Guiding off, it does in a Guide Assistant run, where both RA and Dec are off. So I'd be worried about the Dec line "drifting off" - but he doesn't say if it's continuous drift, or just normal movement above and below the line. so who knows ? If he's happy with +/- 3arcsec guiding, then we can close this one off. Michael

Have you read the PHD2 Manual, particularly how to use Manual Guide ? https://openphdguiding.org/manual/?section=Tools.htm#Manual_Guide Each press of a Manual Guide button sends a 5000ms pulse in your case. Holding it down doesn't send any more pulses ! Particularly when trying north or south, it may take several presses before the guidestar moves, because of Dec Backlash. You mention EQMOD, you might not have set the Pulseguide setting higher than the stupid 0.1 default. That setting will mean PHD2 is sending much much smaller pulses than 5000ms would send with a correct EQMOD setting. Michael

The spec says for guiding "short to medium length scopes". You might find that the 6.44arcsec/pixel image scale a bit too large to guide a 750mm FL ??? scope. Michael

Hi Jonathan I would securely mount the WO setup on a plate between the 6" scope's rings. Michael

Hi Ashveen We're all assuming that you're guiding your SA. And we don't know if you have a telescope, or a DSLR, or astro camera plus lens, you haven't said.......? Two of the PA routines in PHD2 were written by an Australian, specifically because southern PA is so difficult. Static Polar Alignment (SPA) and Polar Drift Alignment (PDA). https://openphdguiding.org/man-dev/Tools.htm#Polar_alignment_tools If you aren't guiding, then classic drift align, using an eyepiece if you have a telescope on the SA. If you have only a DSLR and lens, then point it south in your case and around Dec=0, centre a star using LiveView and x10 display and grid display (LiveView menu). 5 minutes later fire up LiveView again and look for how far the star has drifted north or south due to PA error. Adjust mount azimuth. Repeat for a star to the west or east and adjust mount Alt. Very tedious, so hope you have guiding ! Michael

This is a DIY section, so prefer your zip-tie solution to spending money . Michael

Hi Paul Some contradictions here. If your PA was "perfect" then Dec wouldn't be drifting out of sight ? It's best when looking at problems to be specific, so better to quote PA error in arcmins, rather than "perfect". Again "perfect" 300 second exposure images at 600mm FL probably means that your +/-3arcsec RA was matched by a similar Dec error. Yielding round but bloated stars. A guidescope and camera on a DSLR hot shoe ? In theory that is not "securely fitted". But I should follow my own suggestion and ask you to post a sub, and the PHD2 GuideLog, rather than making guesses ! Michael

If the Calibration is going wrong for reasons as yet unknown, then the PHD2 DebugLog might point to what's going wrong with the mount. Michael

Centreing a target with the handset then SYNCHing will improve the mount's skymap. Centre and Synch a star near your target, then a GoTo the target should be spot on. Or you can PlateSolve. Michael

Ah darn it, missed that ! I'd stick with 3.27, except the colour scope will struggle even more. But 30 steps to Calibrate means something isn't right, maybe EQASCOM guide rate ? Michael

From your GuideLog: You should Calibrate at Dec=0, not Dec = 38, Dec = 41, etc. PHD2 has been told your guide image scale is 6.45arcsec/pixel. I calculate it to be 3.27arcsec/pixel, so you have a wrong entry somewhere. (I notice you did the first Calibration with Guide Rate at 1.5arcsec/sec, but you corrected that for subsequent Cals. ) So Cal on later runs is taking about 30 steps instead of about 12. Colour guidecam is struggling, many Star Lost situations. So get your image scale and Calibrations right, do a Guide Assistant run on Target, to set Minimum Moves and Dec Backlash Compensation. Then post the GuideLog. You don't seem to have read any PHD2 instructions, there are plenty of Help and How To guides in the Help menu. Start with this one: https://openphdguiding.org/phd2-best-practices/ Michael

Forgot to say - you must Dither too ! Michael

Guidescope Aperture = 500.0 m ? Arecibo Lives !! Shouldn't matter if FL is correct. Michael

If it's cloudy tonight you'll have plenty of opinions to read on the subject of DSLR Darks with different temperatures ! I load Bias subs as Darks in DSS with my 6D. Michael

Hi Nigel Upload your GuideLog and DebugLog to the PHD2 Help Forum. Instructions in your PHD2 Help menu Be careful to select files with the correct dates in the filename. https://groups.google.com/g/open-phd-guiding Michael

I expect you meant 2arcsecs, not degrees ? Dec drift is due to PA error, but poor Dec guiding will be down to Dec Backlash, Dec balance, and PHD2 settings. It sounds like you want to spend money instead of gaining experience. Read some of the PHD2 Help and How To guides in the Help menu. Michael

To save time faffing with those too-coarse adjustment bolts, be aware that the PHD2 Developers say you only need 5arcmins (yes MINS) or better PA to guide with PHD2. Obviously for non-guided you'd go for 12arcsecs. When you get Pole Master you'll doubtless find different results to SharpCap PA. That's because PA error is an incredibly small angle to measure with any hope of consistency. I'd of thought SharpCap was more than adequate, and speedy. Cables dragging on the lawn ? Not a good idea. Loop them to a point near the top of the tripod. Michael

Just a small detail. The screenshots become more meaningful if the Settings are arcsecs instead of pixels on the Y-Axis. Michael

So he does. Nowhere in the description of the problem, only in the title. My bad. Is that in Ekos ? Doesn't seem to be doing the job then. Michael

PHD2 logs are stored every night in the PHD2 folder on your PC, so you can post now, no need to wait for the next night. GuideLog, not the DebugLog, and check the date in the filename. Michael

If guiding errors were definitely the same during the trailing episodes (check the guidelog at the times of the exposures), then it's differential flexture from who knows where. If the guiding errors increase (were the trails in Dec or RA ?) then that's your culprit. Michael

If removing the battery cures this, than it's not a camera setting that's wrong. Same with no lens ? Not connected to a PC ? I read somewhere it could be "Canon's way of telling you to buy a new camera".................. 😆 Michael

Does your mount have its own Dec Backlash Compensation, and is it switched on ? Michael