michael8554

Perhaps you're right, my quick look suggested the error was diagonal. If everything is screwed then that only leaves the focuser. I know from modding Canon DSLR's that they adjust the sensor tilt to 0.03mm tolerance. That's not a lot of movement ! What kit are we talking about, you haven't said ? Michael

Assuming that your video covered a wide range of sky and so different camera orientations. looks like there is a fixed tilt, not image train droop. If in doubt take an image, then another of the same target, with the camera rotated 90 degrees. So one of these may help: https://www.firstlightoptics.com/adapters/astro-essentials-m42-t-tilt-adjuster.html Michael

Here's what I don't get - why a new 3556mm FL scope and immediately look to reduce the focal length ? The 12" is 3048mm FL and £3k cheaper ! Michael

I believe any mount without a GPS unit will require you to enter time and date. I'm more familiar with Meade mounts and that's the case for all the non-GPS mounts. You can probably buy a plug-in GPS for your mount, but the manual method takes less than a minute. Michael

IMO this is impossible to guess. Get some 400g, 200g, and 100g cans from the larder, put them in a bag, and hook them onto the front of the OTA. Add or subtract until you get balance. Then weigh the package on your kitchen scales. Michael

For it to fully work you need the handbox : It's called a Meade 497 handbox/handset/controller, you can get a pre-owned one for 50 bucks or so. The scope can be powered by internal batteries, but these deplete very rapidly, giving strange behaviour. Don't use rechargeble batteries, they only give 1.2V instead of 1.5V of alkaline batteries. Even better use a Mains Brick power supply. Michael

Hi Scott You'll have to post one of your subs so we can make a judgement . Michael

I'm afraid there's so little data in your stacked image that stretching it like Davey did is not going to give you anything meaningful. Can you tell us what your equipment is, and details of your exposures ? Could be due to Flats robbing all the data in the subs like Davey says. But I think you're going to have to increase your individual exposure time significantly, as there's a limit to what you can get with hundreds of very short exposures, and this looks like it. Michael

Hi Stu jambouk beat me to it ! I'd be very happy with these star shapes on my setup 🙂 But to be super-critical: You should look at single subs, stretched if necessary, because Stacking will have merged the star shapes to an extent. So there's a hint of distortion on the left side of the image, which could be due to tilt. Try shooting the same image with the camera and CC rotated 90 degrees. If the distortion moves to the top or bottom of frame it's tilt, if it remains to the left its probably in the optics and not correctable. Michael

In terms of quality and lack of compression artefacts, the best cropped movie mode for the 600D is LiveView 5X: https://www.astropix.com/html/i_astrop/eq_tests/canon_one_to_one_pixel_resolution.html Michael

Roughly speaking there are three shapes of stars due to guiding: Small round stars, fat round stars, and elongated stars. So if you want small round stars you'll have to work on your guiding. RA RMS is 50% to 70% higher than Dec, which means elongated stars. I was in the elongated stars situation. Best RA I could consistently get with OAG was below 1arcsec at 1280mm focal length, , but Dec was even lower, so I set a small drift in PA and set Dec Min Mo to up the Dec RMS to match RA. Michael

You can't get a meaningfull Calibration "near Polaris". Best position for Calibration is pointing near south and at Dec 0 (that's not the horizon) The calibration moves should be at 90 degrees to each other - the RA Cal moves the scope "horizontally", the Dec Cal moves the scope "vertically". Instead they are superimposed on each other, and RA and Dec commands in Guiding are mirroring each other. That could be due to a faulty ST4 cable - they are incredibly unreliable for some reason. Or the NINA setup, I'm not familiar with that, hopefully Kens will decipher the Debug Log 🙂 Most of the Calibrations end before Dec Cal starts - is that PHD2 stopping it, or you ? Try again at Dec 0 and post your Logs - zip not rar, I had to download an extractor for rar. Michael

Full Version of 4.2.5 has been released, might fix your problem 🙂 Michael

Can you post a jpeg of one of your subs ? If the 1300D is Baader modified then bloated stars due to Infrared reaching the sensor shouldn't be occurring. Michael

There have been a few problems with 4.2.3 over the past few days, they're up to 4.2.5 with the test builds. But your problem may just be settings. Michael

Google is your friend ? You said in Europe, here's a firm in Germany: http://www.klaushelmi.de/en/ Michael

All those settings look correct. Why don't you post the PHD2 Guidelog, hopefully it includes the Calibration ? Michael

Yes, that's what I was trying to describe. Despite being held by the 3 screws I don't see them being a source of flex. Michael

Hi Craig The non-filter carousal version of the ZWO OAG has M threads on all three interfaces once the 1.25" guidecam adapter is unscrewed from the periscope. The three screws are to hold the Image Camera Interface in the OAG body, and can be tightened and forgotten about. They allow the adapter to be positioned in 3 positions 120 degrees apart. It's a large version of the camera-specific adapter in the T ring, and no more wobbly than those three tiny setscrews in the T Ring. You can buy identical no-name OAGs for less than the ZWO one.

That large 10 second component is a worry often reported on the PHD2 Help Forum. Their suggestion is to use the PHD2 PPEC as you are doing, but set the period to a fixed 10 seconds. Also 3 seconds exposures seems slow ? Long-term I would look at your guidescope in adjustable rings, which can lead to Differential Flexture. Have you ever needed to adjust them ? Probably not, so clamp rings are better. Also I guide at 1300mm with a 200mm guidescope, you could save weight too. The two wires coming off the mount control panel could do with supporting. Michael

You could split your image into RGB in your editing software, convert them to layers, shift R and B to correctly superimpose on G, then flatten to one layer. Michael

The MPCC is suited to Canon DSLRs which are 44mm Back Focus + 11mm for the T Adapter = 55mm Nikons Back Focus is 46.5mm I believe, have you accounted for that difference ? The Barlow makes it difficult to judge what distance to set the MPCC to. But the charts often shown on SGL suggest the camera is too close, as Mark has suggested. Michael

Google is your friend ? Loads of short ones if you look: https://www.ebay.co.uk/itm/Topiky-2-Inch-to-1-25-Inch-Telescope-Eyepiece-Adapter-Ring-Lens-Mount-Adapter/223893785881?hash=item34211c0d19:g:cvoAAOSwUOReOcF1 Michael

We had a garage clear-out recently. I can confirm we can now see Space. Michael

The link from Tenor Viol isn't for PA in my opinion, it's for Star Alignment. After Rough Align, you will have to carry out a Drift Alignment or DARV Alignment, using the wedge controls only. THEN you can carry out the EQ North Align, using only the handset controls to centre each star, and ENTER to confirm each star is centred. Michael