jif001

Had a go at this for the first time this month. Previously I had no chance because I can either see Polaris or M16, but not both, so polar alignment was not possible. Then I discovered NINA’s three star alignment and it was game on. The other problem is its low altitude and - a common theme! - trees and houses in the way. I managed to get an hour on it as it drifted through a gap, but on three nights, so 3 hours of Ha integration so far. If there are no more clear nights very soon I won’t see any more of it this year and it will take me years to get a colour image!

Problem solved. According the Third Law of Sod, despite all of my efforts checking the cables and connections for continuity, I today found a broken wire in the ‘Dec out’ DIN socket. I soldered it back and now everything is fine again. I just wish that had revealed itself before I bought a new motor controller … Well we learned one thing from this sorry tale - a new (MC019 RevD) EQ5 controller with the above DIP switch change will drive an EQM-35. It seems to drive it at a different rate, but I suspect that’s due to an error in the firmware that is said (on the Skywatcher website) to affect the controllers with the USB port (as in this case). There is new EQM-35 firmware there but I’m not inclined to flash it - might try returning this new unit, or selling it on. IMG_0478.MOV

Ah well, no luck with that. The new controller works but the problem persists. Now I’m stumped. I’ll have to go right back to the beginning and check everything again. It’s clearly not the controller after all!

Whoop! DuckDuckGo to the rescue!

I went for it and bought the controller. It’s a different board from the ones pictured above, having no jumpers but instead it has DIP switches. Any idea what the switch settings should be for an EQM35? Google isn’t helping!

Ha! It did strike me as odd that they would put a USB socket on it and still rely on an arcane method of updating the firmware. I should have listened to myself!

No. As I said early on, I’ve been using it for 18 months and it’s given me some great images. It’s only this past week that it’s failed on me.

Well that worked. And at the same time it didn’t. Connected to the handset ok and updated the handset firmware. Connected to the mount ok and updated the motor firmware. But the problem persists - suggesting it’s a hardware problem. The only option now is a new motor controller

Interesting. I found this https://olegignat.com/sky-watcher-synscan-v5-hand-controller-firmware-upgrade/ - see his rant about the USB connector. I must admit that based on this I didn’t try it but I will now. I’ve been using an EQDIR cable and a mini PC for imaging - I’ve never used the handset.

Yep. Tried the handset from my EQ6R-Pro. Tried both handsets and both cables in all combinations. No change.

It’s definitely an EQM-35. The M stands for ’modular’ meaning the dec axis can be removed completely turning it into a tracker (Star Adventurer style). As a last resort I can delete the dec axis altogether, although I’m hoping that because the dec motor runs at top speed I’ll still have something of a GOTO function on it. No idea about its history though. The firmware update is proving more problematic than I expected. Little did I know that the USB port on the handset can’t be used for that. I need a USB(FTDI) to RJ11 connector. The ‘Skywatcher’ labelled ones are (of course!) outrageously priced so I’m looking at cobbling one together out of an RJ11/RJ11 cable I have, and a USB(FTDI)/RJ45. Just trying to establish the connections needed … if I end up with a new board I’ll be happy to let you have the old one, but if you manage to fix it I wouldn’t mind having it back as a spare, just in case!

Here’s some video - first on rate 9 then on rate 2. When connected to the RA output the motor works normally. IMG_0450.MOV

Tried a different PSU. No difference. Swapped the cables. Same. No connection problems. The issue must be with the board. Pics attached confirming it is the type you posted above. However, as you can see, there is a jumper in place. I think I’ll pass on replacing the IC - there’s no guarantee that’s where the problem lies, and my soldering skills are mediocre at best! I’ll have a go at flashing the firmware. If that doesn’t work I’ll bite the bullet and buy the new unit, then report back here good or bad!

The PSU can deliver up to 10 amps and has been running this rig for about 18 months without issue. I have another 10A PSU on an EQ6R-Pro rig that I’ll try just to check though. A connected power distribution box reports 13v. I don’t know the retailer or the age of the mount as I bought it second hand. It’s given me good service until now. All I know is that it must be over 2 years old. I had a look at the board yesterday just to see if there was anything obvious (broken connection / evidence of a blown component) and there was nothing. When I found this thread I noticed that the picture you posted above (preceded by ‘I was half right’) is of the same board. The hand controller reports no errors. With nothing else connected the motors both operate, but the dec motor will only turn at high rates. At low rates it just twitches back and forth. I’ll do a few more tests today to be sure it is the controller at fault (recheck the connections / try a different PSU /…). I’ll get some pics of the board too. RVO have the EQ5 unit in stock, but maybe I’ll try OVL first.

I’d like to resurrect this thread if I may. I have an EQM35 and the dec motor stutters before starting up on rate 9, and doesn’t manage to move at all at most of the lower rates, basically just twitching, meaning it can’t track in dec. I suspected the motor so tried a new stepper only to find it sufferers exactly the same problem. I tried the dec motor on the RA connection and it worked fine, so the motor isn’t the problem. I checked all of the solder joints and cable continuity and it’s all fine. That leaves only the control module. Sourcing an EQM35 control module seems impossible, but I’ve found an EQ5 module in stock. So, the same question arises - could I replace my EQM35 module with an EQ5 module? From this thread I’ve understood that the hardware is much the same with some jumpers configuring the mount type. Skywatcher does have EQM35 firmware available on their website. Before I blow £120 on it, is it likely to work?

I thought about mounting it on the OTA - much better for cable management - but I change OTAs occasionally and re-configuring it all can be a right royal pain. As a result I had a USB-3 hub fixed to the leg and a cable loom running to that. It’s now been replaced by the mini PC.

Same problem, different solution. I made this to mount one on the leg of my EQ6R. The PC mounting plate (red) fits into the slot and bolts in place, leaving space all around for air circulation and cable connections.

I modelled a Samyang 135 and built a mount around it which also houses a focus motor. It borrows from existing designs I found, but I heavily modified it. I made a similar thing for a WO SpaceCat 51 (now sold). Those two items alone saved me more than the cost of the printer. I’ve also made Bahtinov masks, replacement alt/Az adjustment knobs for my EQM35 and EQ6R, a carry handle for my 102mm refractor, polar scope adapter, polar scope illuminator … and much more besides. Yesterday I printed two brackets to securely attach mini PCs to my mounts for wireless remote imaging. Have a look on Thingiverse - there’s a lot of Astro stuff there freely available.

Manually, using the controller that comes with the motor (just 2 buttons and a speed dial) and a 5m RJ10 cable. With a bahtinov mask and live view on the laptop screen, focusing is a lot easier than going back and forth making small adjustments!

Won’t necessarily use it much myself, just an interesting experiment.

Here’s an earlier test with 1mm vanes (rather than 2mm used for the Pleiades). Interesting how the lines are broken - some destructive interference going on?

I took an existing .stl file and modified it, creating a hole to delete the Bahtinov pattern then adding the vanes

The whole process of astrophotography is about changing the record of those photons that we carefully capture. If we didn’t then all we would have is a bunch of linear images that would offer very little interest. No two images of the same target will be the same as a result of different ways of ‘post processing’, and let’s not forget that SHO is a complete misrepresentation of reality. There’s also a certain aesthetic appeal to star spikes in an image. The real point here is that if you want them with a refractor, you can have them: you could think of this mask as a form of optional ‘pre-processing’. Overall, what you do to capture and process your images is a matter of personal taste and preference. 👍🏻

The effect is the same, but tweaking an image in software doesn’t really fit under the heading ‘DIY Astronomy’ 🤷🏻‍♂️

Why not just take a blank image and paint some stars on it? 🤔