michael8554

Then at the bottom of the page are what appears to be the instructions and links to the downloads - but I haven't tried to download them. Michael

I use dumbells on my 3D balance system. Cut 25mm diameter "cotton reels" with a 27mm Holesaw from appropriate thickness wood. "Penny Washers" either side and jubilee clips to secure. Not very secure, you might think of a better fix than the jubilees, mine are on threaded rod so are held tight with nuts either side. Michael

It's gratifying when one's long range detective work turns out to have been helpful. A final thought. I reported on Saturday that your RA had a 13.6 sec component. It has been suggested on the PHD2 forum that down the road you rotate the current mesh position of the intermediate gear in the RA gearbox (5). I would look before and after at the Analysis section of the Log Viewer to see the effect, finding the sweet position will be hit or miss. Michael

That's like asking what day we will leave the EU...... Several have said the combination works fine, I'm just suggesting you avoid possible problems by using clamped rings. Michael

You can up the ISO to silly figures, but a bright star nearby is better. Same here, which is why I can't get my head around PemPro, SGP, PixInsight etc, Still a worthwhile read. Successful Calibrations first try - what did you do ? Scond guide session - outstanding ! Now you can offer advice to the next problem poster ! Canon Utilities comes on the CD with your camera, or you can download a CD image from Canon USA Michael

And here's a good pdf on how to analyse your guiding: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=2ahUKEwjiqvny3rviAhUwVRUIHXCbDFkQFjABegQIAxAC&url=https%3A%2F%2Fopenphdguiding.org%2FAnalyzing_PHD2_Guide_Logs.pdf&usg=AOvVaw208LGfOpq-qd2bYGZi_iQL

Here's what a PHD2 Help File says about Differential Flex: "Many imagers go into denial about this and say “I’ve got everything clamped down really tight, nothing is moving, it can’t be differential flexure.” Yes, it can be. Every single mechanical interface on the system - clamped, threaded, geared, set-screwed, whatever - has some possibility for movement. And all you need is a movement of a few microns to create a problem." A few microns is a fraction of the thickness of a hair. Your guiding may look perfect, because PHD2 is failhfully following every move of the guidescope. Unfortunately the Diff Flex means the perfect guiding is in fact wobbling the imaging scope ! So the flex of adjustable rings is a problem that will not be apparent in your guide graphs. Michael

This my Focusing setup: The Canon Utilities Zoom View is showing the magnified LiveView image The red circle in Bahtinov Grabber hovers over the centre of the cross when correctly focused, with focus error text to the left. The small Canon Utilities remote has most of the camera settings available, the red circled icon opens a small long exposure sequencer that fits nicely in the space under the remote. As each sub downloads it opens ZoomBrowser full screen and displays a large image and a Histogram. Nice and simple and relatively uncluttered. Michael

Go into the Setup menu and under GPS there are 3 settings. Select OFF Power off and on again First time only check in Setup / Targets / Sites / Edit that your location has been stored, not sure if you needed that info when GPS was on. Daylight Saving No? You can toggle to Yes if preferred. Time and date then only take a minute 😆 to enter. If you get around to applying the fix, the Star GPS guy's fix saves a lot of your settings, Meade doesn't. Michael

Can't comment on the cameras but their mounts are not optimum. No need for adjustable mounts with current sensitive cameras, soft tipped screws lead to differential flexture and elongated stars. Clamp the guidescope down to the mount as rigidly as you can - micron size flex in the guidescope leads to pixel moves on the imaging camera. Michael

The dumbell shaped stars are due to backlash. The mount has spent some of the 120 secs at one end of its backlash, then flopped to the other end, giving two stars joined by a trail. On some shots this hasn't happened, so balance must be right on the edge. Could also be Periodic Error, with the good shots coinciding with the PE peaks where RA change is least, but I prefer Backlash as the cause. Balance slightly heavy in one direction. Michael

I've looked at the screenshots of BYE and APT and found them to be too complex for my needs, filling the display with unwanted tools and info. I use Canon Utilities which takes up little space on the screen. Good luck with your next session Michael

HFD 1.5 might be inappropriate for your setup, I still think it's the best way to avoid autoselecting hot pixels: "Minimum star HFD' - specifies the minimum half-flux-diameter (roughtly the 'size') of a suitable guide star. This is probably the best way to prevent PHD2 from mis-identifying clumps of hot pixels as usable guide stars. You can determine a suitable value for your system by manually selecting some small stars that you know are not just hot pixels, then use the star-profile tool to see the HFD values of those stars. You'll want to specify a minimum HFD value that allows selection of legitimate faint stars but not hot pixels." Star Profile is in the Tools menu. A saturated star will have a flat top to the profile, and you'll get a red SAT message on the bottom of the PHD2 window. (You can refine your guidescope focus by getting the lowest HFD figure in the Star Profile window as you focus.) I don't believe you can have too high a snr, but you can have too low, the SNR message at the bottom of the PHD2 window should be green, it goes brown if getting too low. I noticed the other night you focused on Vega, then slewed over to M51. Remember my concerns over micron moves in your guidecam mount ? Well the same applies to your dslr, I always set focus on or near the target because the heavy dslr will sag differently after a slew to a different position. Worth doing if you're picky about star shape 🙂 You should continue with your sub rejection process because you are the best judge of what's suitable. But you should aim to improve your guiding to lower that reject rate. Michael

For the reasons I stated ! As you say, a good qualty tool will crimp to the correct depth, but the temptation is to buy a cheaper tool which may crimp too deep or too shallow. How do you decide how much to spend ? If in doubt buy a made up cable. Michael

The right size for mounting a PST solar scope on a mount might be useful for some. Michael

Look on the 'bay for a 4P4C cable of the required length. DIY cables can be problematic. The crimping is either too soft, which gives poor contact to the wires, or too hard, so the gold contacts are sunk too far into the plastic. Is it 100 minimum order ? You'll have enough to 'practice with. Michael

Pinched shouldn't matter as you said, but you could look at the star shape and Profile as you tighten, back off a tad if you see signs, and decide whether it's tight enough to eliminate flexture. Michael

The LX200GPS ASCOM driver has exactly the same problems, so that one next please ? Michael

Primaluce Eagle wireless control box ? https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.primalucelab.com/astronomy/eagle-control-unit-for-telescopes-and-astrophotography.html&ved=2ahUKEwi46YmP87biAhUvQhUIHQtYD_QQFjAAegQIBRAB&usg=AOvVaw1wx6a0twNJ4AHW7UXI3Krw You'll have to sell two of your mounts to afford it though .......... 🙂 And presumably one of those micro pc's would do ? Michael

Here's what the PHD2 developers said about your Guide Log: "Guiding appears to be limited by the 13.6s period RA error component. I think that the RA guiding could be improved by using shorter guide exposures, like 1s, or 1.5 s at most. I'd also suggest upgrading to the latest version of PHD2 (or better, the latest dev version), and running the Guiding Assistant with 1s exposures to get recommendations for the RA and Dec min-move settings. The ~765mm focal length of the imaging scope should be relatively forgiving and the above-mentioned RA guide error may not even be visible in the main camera subs." So set exposure to 1 second or thereabouts BEFORE running GA, not after as an experiment as I suggested, my bad. Latest dev version at https://openphdguiding.org/phd2-2.6.6dev1-installer.exe Just download and run it, don't uninstall the older one. Without seeing your subs, thay too don't think there will be appreciable drift. The largest component of your PE has a 13.6 second duration, this can be seen in the PHD2 Log Viewer if you select a smoother section of the log graph and click on Statistics, that's why a faster exposure is suggested. Michael

1) To avoid locking on a hot pixel try setting the HFD to 1.5 in the Brain button/Guiding tab, and untick Star Mass Detection. You say you are choosing good unsaturated stars, but you should allow PHD2 to select a star, it knows what's good for it ! Tools tab/auto select star 2) In the left-hand pane of the GA results is Drift-Limiting Exposure, which was 0.8 seconds. But then it also always says to use 1 to 3 second exposures too in the right-hand of the display ! 3) All I'm suggesting is to try a faster exposure, say 1.5 or 2 seconds, for 5 minutes without changing anything else, and see if it gives faster reactions to the excursions, and a smoother guiding graph as a result. If the graph starts to yoyo then reduce the Aggression until it settles. As I said, time to experiment a bit, but allow enough time for each new setting to stabilise. Did you try balancing to take up the Dec backlash ? Easing into my thoughts on your results, I didn't think your "poor" exposures were drifting that much, I'd be interested to see if others agree. What is your criteria? Is it the Score for each exposure in DSS ? Try stacking all your subs and comparing with your best stack, if you're unhappy then ignore me ! Michael

Before I reply fully, some questions for you, but I would say that you are at the stage of fine tuning your PHD2 settings. 1) I notice the 4 failed Calibrations before your final good one. Are you allowing PHD2 to autoselect a suitable star, or choosing your own? 2) The GA suggested 0.8 seconds exposure, which suggests very choppy Seeing, but you used 2.5 seconds - is your camera not sensitive enough to use faster exposures ? The GA is saying that to keep around the 0.10 Min Move, you needed fast corrections, and 2.5 seconds was too slow to catch the RA moves. 3) However I'd say 0.8 seconds is a bit excessive, but what are your guidestar exposures like at say 1.5 seconds ? Michael

With a very basic motor drive, speed would vary with voltage. A better designed drive would only rely on the supply voltage to power a circuit that self regulates the speed irrespective of the supply voltage . I don't know which you have. Michael

The Full-Frame camera may well be vignetted, but you can always crop, down to where you would probably crop with a APS-C. Yes EF lenses may well be expensive, but Chaz is hoping to use his EF-S lenses, so maybe Full-Frame is out. Michael