michael8554

The clue's in the description: M48X0.75 0.75 being the spec of M42 and M48 extenders. Back in the days of film cameras there were many lenses with M42 x 1 threads, which often caused mating problems. Strictly speaking M42x0.75 is T2, M48 isn't T2. Michael

Not according to the GuideLog. Both Cals were at 750ms. Post the Log where you tried 15000ms. Michael

Although your Log doesn't include a Calibration, it appears to have been okay - no error message, Orthog okay, and RA and Dec guide rates close to the mount setting. But that Cal was done on the day before - did you do a new Cal on the 22nd ? PA from the Guide Assistant run was good, 1.9arcmin. There was an advisory to improve the guidescope focus. But the identical RA and Dec moves suggest the Cal from the 21st didn't match the scope setup of the 22nd. Follow wim's instructions. Michael

Yep

The mount is moving and incrementing in a roughly linear fashion. But it's failing to move enough after 60 steps. The PHD2 Calibration Step is 750ms. So as I have already suggested, keep increasing the size of the Calibration Step until Calibration takes about 12 steps. Try 2000ms to start with. Your Guiding Image Scale is Pixel scale = 8.94 arc-sec/px, Which is too high, and is contributing to your Cal problems. Due to the large pixels pixel size = 5.2 um, and the very short guidescope FL Focal length = 120 mm You need either a 3.75um pixel guidecam, or a f/4 50mm or f/4 60mm guidescope. Michael

Dec is short for Declination. So remember Declination / Inclination / incline / up and down Michael

The ASI120mini has 8.5mm flange distance. The focal length is f/4 x 30 = 120mm. So measure about 110mm back from the scope objective. That's roughly where the black front of the 120mini needs to be to get focus. Michael

It's Catch 22 that you need high-mag to accurately collimate, which you don't get with the camera, but do with a high-power eyepiece. But risk the camera setup not having a similar collimation, as in your case, due to tilt. Perhaps you need a Zero Shift Focuser, so that the Primary doesn't have to be moved. Michael

I would stop trying to get 1280mm FL, and concentrate on getting the best Back Spacing, based on images. Image 1 Best right hand side, Image 2 worse, image 3 worst right hand side. Image 1 Poor left hand side, Image 2 worse, image 3 best left hand side. So image 1 (105mm back spacing) could be the best if the tilt were corrected. I'd say you have varying Tilt, or the primary mirror is very sloppy. What magnification are you using for those Airy disks ? You need around x400 for the final tweaks. Michael

Mine's permanently mounted. You can PARK in the default position, or in a Custom Position. Note the Dec reading on the Dec scale, and make a mark on some sticky tape stuck to the mount next to the RA alignment marks on the forks. Then you can loosen Dec and RA if helps with dismounting. Then next time remount, reposition RA and Dec, and switch on. Input Time, Date, and then PA. GOTO, centre on a star near your Target, and SYNCH. Michael

A comprehensive analysis from wimbv of the problems. But you can't specify the Dither based only on the GuideLog. You need to know the image scale of the imaging setup, and Jon has three very different OTAs. The guide image scale is 3.3arcsec/pixel. If the imaging setup is 1arcsec/pixel, a typical Dither of 12 pixels requires the guidecam to be dithered 12 x 1 / 3.3 = 3.6 pixels. For 2arcsec image scale it's 12 x 2 / 3.3 = 7.2 pixels Etc Michael

Hi Francesco According to the GuideLog the Minimum Move setting is 1.5arcsecs on RA and Dec. So PHD2 will not start correcting until guide errors exceed that figure. So no chance of sub-1arcsec guiding :-< Imaging at 1600mm FL with a 900mm FL guidescope is asking for Differential Flexture. I suggest you get an Off Axis Guider (OAG). Michael

If in August the scope was showing correct year with GPS on (not something crazy like 2099) then firmware is up to date. But as you now have GPS off the firmware version isn't relevant. ScopeBoss faithfully replicates the Autostar II handbox. I have my LX200GPS Parked, and GPS off. So with GPS disabled, when you power up and connect with ScopeBoss: Next screen in ScopeBoss is DST. I always have DST off. Next is Time. The mount doesn't remember the time, so you have to input if GPS is off. HH:MM:SS, then ENTER, I input GMT as I always have DST off. Next is Date. You have to input if GPS is off. 20 February 2020, then ENTER. There's an option in ScopeBoss to reload the menus from the mount, takes about a minute. RESET at your peril, it wipes ALL your mount settings, the mount thinks it's location is back at the factory in USA. Michael

Have you updated the firmware since 2019 ? Is GPS enabled ? Michael

Does it work okay with the Autostar II handbox ? If GPS is enabled it may override your attempts to manually input. And have you updated the firmware to overcome the 2019 GPS Rollover ? Michael

Hi Mike, "i saw some advanced guys with some really detailed moon photos that I just could not get near." The ZWO ASI 462 is a good choice for detailed close-up moonshots. But no good for whole moon images without mosaicing. Michael

Hi Mike Perhaps you could explain your choice of the ZWO ASI 462 with a tiny 5.6mm x 3.2mm sensor, to replace the 650D with a 22mm x 15mm sensor, for "moon and andromeda" ? You'd need a X0.50 Reducer (if such a thing exists for the 150PDS) to completely frame the moon. Michael

Hi Ian Not sure what this is you've posted ? I'm guessing these are switches to change the direction of slews. An intuitive thing: When I press the UP button I want the OTA to move up. OR When I press the UP button I want the stars to move UP in the eyepiece/finder ie the OTA moves down. (All depending on any flips due to the optics) Shouldn't have any affect on guiding, PHD2 will work out which way the mount is moving by the Calibration results. Michael

Good point. That would make your guidescope f/5.9 x 2 = f/11.8 !! I know the LodeStar is sensitive, but that's pushing it. An OAG on the FSQ85 would have the same problem, so ASI 120MM mini it is. Michael

I don't remember the reason, but choosing ISOs that aren't whole-stop increments is not recommended for long exposures. So use ISO 800 or ISO 1600, I would say 800. Michael

Your image scales aren't unusual, so I would look elsewhere for the cause of your guiding problems. Is it RA or Dec that is suffering ? Post a GuideLog that includes a Cal and a Guide Assistant run. Michael

The guide and imaging cameras don't have different Binning, they both have the same Binning, X2 ? The factor takes into account any amount of Binning, if you include that in the calculation of the respective Image Scales. Michael

!05mm from the rear of the f6.3 Reducer to the camera sensor is the recommended starting backfocus. You should post a short-exposure jpeg of a sub so we can see if that distance is too much or too short. Without the FR, the distances that Celestron recommend in that link are probably the result of extensive tests, so very Real World. But I'm not sure what you will prove by testing without the FR. Post an image with the FR. Michael

PHD2 gives up trying to Calibrate after 60 steps if insufficient movement has been measured. 1. Perhaps it's as simple as you are asking PHD2 to Calibrate Dec ? The Star Adventurer doesn't have a Dec Drive, so you should deselect Dec guiding before Calibrating. 2. You have a ZWO 30mm f/4 guidescope. What focal length did you enter in the PHD2 Equipment Profile wizard ? 30mm is the aperture, but the focal length is f/4 x 30mm = 120mm. That's explained at 14:40 in the video you looked at. 3. If you have 120mm entered, then perhaps the Guide Rate is too low. If the Star Adventurer doesn't have a way of setting the guide Rate, experiment with the size of the PHD2 Calibration Step. Cal should take about 12 steps Try doubling to start with and see how many steps Cal took. Videos are only good if the author knows what they're talking about. Best to read the PHD2 Instructions in the Help menu. And post the GuideLog. Michael

The sensor is buried inside the blue casing a distance that ToupTek don't show in their dimension diagrams. Is focus failing because you can't rack the focuser far enough out ? Try pulling the camera out of the focuser. Or does the focuser bottom out ? Have you removed any unnecessary spacers from the focuser ? Michael