Starwiz

Thanks both! I identified it as a font from the Nirmala UI font family, Malayalam from the Indian sub-continent. For reasons unknown, this was set to the default language in CdC and I have no idea why??? It was only in CdC as none of my other applications have been affected and uninstalling and re-installing CdC didn't solve it. I ticked the en - English box, then applied the settings and it seems to have solved the problem.

Has anyone else seen this issue with the CdC menus? I have: Run a deep virus scan - no issues found. Downloaded and re-installed CdC, but the problem remains. I thought it could be a FONT problem on my laptop, but then I would expect to see the same issue with all the menu tabs. As you can see, File; Telescope; Update all look fine. Thanks John

To take the flats, I used the Flats Aid in DSS. For the light, I used 3 white pillowcases and a Yaufey A3 Copy Board. Thanks.

Here's a stretched image of the master flat for the red filter created using 30 flats in DSS. The dust mote I've highlighted is still visible in the Red image I've stacked when I stretch the image. I've used 30x flats, 30x dark flats, 30x darks and 40x lights. So, the dust mote isn't being fully cancelled out by the flats in DSS. Does this mean there is something wrong with my flats, or could it be something else? Thanks John

I learned to solder through 12 years in the R.A.F. as a ground comms engineer. Although, I have to say I've barely picked up a soldering iron in the last 30 years or so. Writing software came later, although mostly in high level languages. Well done on the brick laying. John

Thanks. So do I. 🙂

Just to report, I've now re-soldered the connector joint while pushing on the top of the connector. There is now a leg visible on the underside. Not my best soldering as I couldn't get hold of any solder today. The connector doesn't quite line up with the rectangular hole in the plate any more, but I can live with that and have put a piece of insulation tape over the gap. I've powered up the mount with a laptop connected and used CdC to slew the mount. All is looking good so far. John

Ha ha ha. I do now. My other two soldering irons are in the loft of our UK house which we're renting out. We could only bring so much stuff over with us when we emigrated in 2019 and I haven't been back for more than a year due to the CoVID situation.

Yes, no doubt. Tin lead solder is more compliant so less likely to fracture (lead being a softer metal). I went through all the pain of switching over to a lead-free process as an electronics production engineer. 🙂 John

I've just bought a soldering iron, so hopefully I will find out soon. John

Yes, I've just double-checked and it's the way the light is reflecting. Thanks John

Many thanks for the suggestions. UPDATE: This morning I tried tracing the power with my multimeter, powering the mount with the battery pack. Still no power on the PCB. And then, the LED came on as I probed the back of the power connector. I had a closer look at the joints at the power connector and I have to say the soldering standard would fail inspection in most electronics companies. The through-hole component has been soldered without one of the leads being through the hole. This would make sense, as the power connector is taking a force each time it is plugged / unplugged, so if the soldering standard is below par, it is likely to fail at some point. Time to go and buy a soldering iron. John

I set up for an imaging session last night, switched on the mount and there was no red LED showing. Further investigation showed the power supply was dead. I tried powering up the mount from my battery, so using a completely independent power source. When I switched on there was still no LED and the power supply LED also went off. This tells me there is a short somewhere. I've had a look, but can't see anything obvious. I'm surprised there's no conformal coating on the PCB, given the environment the kit is used in. Does anyone know if it's possible to buy a new control board? I really don't want to have to send the mount away for repair as the cost of postage will be huge from here given the weight. John

It depends what you have in your image train and the thread sizes. I was able to make up the 58mm (optimum 57.5mm) from the sensor to the CC by using a combination of EFW, 16.5mm spacer and the OAG that I already had. But you should be able to calculate what you need and find them online somewhere. e.g. https://www.celestron.com/products/m42-spacer-kit I'm looking forward to trying it out on the stars now. John

SUCCESS! I didn't know that bit came off. Both cameras now in focus. Thanks for the recommendations, I've been thinking of getting a better guide camera for a while as the ASI120mc isn't the best for this. Many thanks again for your help. John

Thanks, here it is. With the focus position as shown, the main camera is in focus with a back-focus of 58mm from the sensor to the CC. The guide camera focus can be adjusted by loosening the screw and moving it toward or away from the OAG. As shown, it is fully inserted into the OAG with no more play, but to get the guide camera to focus, I need to move the main focus barrel inward another 5mm towards the telescope, which of course puts the main camera out of focus with the 58mm back-focus distance. John

Many thanks for the suggestion. I couldn't do it with the barrel collar as the CC wouldn't fit, but I got it working by pushing it straight into the focuser with no collar. I've achieved a back-focus of 58mm by using the following: Camera = 6.5mm EFW = 20mm Spacer = 16.5mm OAG = 15mm Unfortunately, the OAG camera won't focus with this arrangement. The OAG is mounted next to the CC but even with the prism adjusted fully inwards, it still requires another 5mm inward travel of the focuser to get it in focus, which of course puts the main camera out of focus. How essential is it to hit 58mm back-focus? If there's not much leeway, I'll be going back to using a guide scope with a rather expensive spacer in the main optical train. Thanks John

Thanks, I will have another look at this tomorrow in the light. John

So, without the CC in place, my set-up is as follows: ASI1600mm-pro Camera (6.5mm) ZWO EFW (20mm) 12mm Spacer 16.5mm Spacer Distance from sensor to focuser = 6.5+20+12+16 = 55mm Focusing on a distant building on the horizon - without the CC it's in focus with the focuser about mid point in the available travel. On inserting the CC, with the same spacing as above, the focuser had to be wound fully in, but it was still not enough to obtain focus. Image with the CC and focuser wound fully in. Thanks John

Thanks. I will try another experiment in the daylight tomorrow. John

Without my new CC, I've not had a problem achieving back-focus of 55 mm. I've just checked it again. So I need 57.5 mm back focus from the CC to the sensor as I'm not using the lock-ring. I can achieve focus with a back-focus distance of 36.5 mm from the CC to the sensor with 12 mm of inward travel left in the focuser when it's in-focus. To get the required back-focus for the CC, I need to add an additional 21 mm of spacing, but I have only 12 mm of inward travel to focus with if that makes sense. Thanks John

I can't focus with either. John

Thanks. With that spacing, I can't focus. Does that mean I have to move my primary mirror forwards somehow? John

Many thanks. Now I can start playing with spacers. 😀 John

I have the Baader Mark-III MPCC Coma Corrector. It says it requires a back focus of 55mm. Does this mean 55mm from the camera sensor to the coma corrector or 55mm from the camera sensor to the telescope's focuser? Thanks John