symmetal

With many people singing the praises of Kstars/Ekos, I've been dabbling with Linux again. Many years ago I had tinkered with Red-Hat Linux so have some knowledge. ? Does anyone know of the easiest way to do dual scope imaging with Ekos and INDI. The latest windows version of Kstars works fine (many posts recommended running Kstars in a linux VM on Windows). I installed INDI on a Pi3 running Ubuntu Mate and it all communicates fine using the indi-web Manager on the Pi. Not having USB3 on the Pi I installed Ubuntu Mate on a cheap Mini-PC I had lying around (Intel Atom, 2GB ram, 32GB SSD) as it had USB3, and it works well apart from not detecting the WiFi hardware. For dual imaging I assume two instances of Kstars have to run on the Windows PC. It would be nice if you could run 2 Ekos sessions with 1 Kstars but it seems not. On the scope mini PC, could the INDI server communicate with 2 Kstars/Ekos sessions at the same time so that you have 2 scopes and 2 focusers communicating through INDI. I assume not as searching the web the two scope solution seems to be a 2 Pi setup with the second Pi 'chained' to the first so all communication is via the 1st Pi. Another thought is would it be possible for the scope PC to run 2 separate INDI servers with one server linked to each Kstars/Ekos session. I could have the Pi 'chained' to the Mini-PC at the scope but thought there would be a more elegant solution using just one computer. Currently I have a more powerful Windows 10 mini-PC at the scope running two instances of SG-Pro, PHD2 and CdC and that works well. The Mini-PC, USB3 hub, dual focus controllers, dew heaters etc are all in a box attached to the dual scopes to minimize long, flexing cables so space/weight is at a premium. ? Alan

If you haven't already got it the SGP update patch is now released for version 3. Alan

Ken & Jared (developers) have responded apologising for the late reply but they've been away with limited web access. Ken has said he's fixed the problem and should release a patch later today. The problem was an upgrade made to the Skyview servers. Alan

If the frame/mosaic images are in your cache from previous requests it works OK. Have you tried it from a new target? If it works for you, you could charge people 5p a go to get the cache images for them. Alan

Up until yesterday neither had I. Have you tried it in the last 24 hrs Steve? There's a lot of posts on the SGP forum reporting the same problem. Still no response from the developers. Alan

The wizard returns a blank 'Error' when fetching the image. There are reports on the SGP forum of this and it seems SGP is not handling the image response from NASA properly. Pasting the failed image request listed in the error log into a web browser returns the image OK. It seems the format might have changed such that SGP doesn't accept it. No response from the developers yet. Alan

I've opened up the Synscan controller from my EQ3 Pro and it is the same PCB. U9, just above C55 is a 5V, 1A regulator. It's marked 17-50 with a 'Diodes Incorporated' logo. Here's the data sheet. C55 is most likely the output electrolytic (writing on it is too small to read). If it was a 6.3V capacitor and the regulator failed and went in/out short that would explain it smoking. U10 is a 3.3V regulator and if its input was the 5V rail that could explain C3 smoking too. If the 5V actually did rise to 12V then unfortunately several other ICs would also likely have been damaged. ☹️ If the fault was just due to C55 going short circuit and smoking, U9 would have gone into current limit so it's unlikely C3 would have been damaged. Alan

My EQ3-Pro GOTO had exactly the same issue with the RA setting circle. It had been tightened up too much when I got it as I had to use some pliers to release it. When tightened up there is a grinding noise at some spots when rotating the scope in RA. I assume the screw has punched through what it tightens against and is fouling something inside. I just leave it undone and there is no problem. The DEC setting circle does seem to have been set wrongly on yours. With my scope at the home position the arrow does point to 90. You can easily alter it by loosening the hex headed grub screw in the side of the DEC circle and resetting it. That's the only thing I use the DEC circle for, setting the home position, so it makes sense to have it reading 90 at the home position and be useful. The setting circles don't have any other use on a GOTO and they're not much use on a non-goto either. Alan

That's how I did my 125, but all the isopranol containing the dissolved seconary glue was collecting around the edge and seeping around the 'rubber' ring holding the corrector plate. In the end I decided to remove the plate from the cell as it was much easier to clean. Alan

Just concentric with the secondary mirror circle as best you can. It's not critical as only the centre portion of the secondary is actually used. I used a couple of tiny dabs of araldite to hold mine back on. Probably not the best solution but it's not coming off again. Alan

It's just the plastic light baffle which was stuck to the secondary mirror which has fallen off. The secondary mirror is the reverse side of the silver spot in the centre of the corrector plate and can't come off or move. You'll need to glue it back on. The front corrector plate can be removed by inserting a tool in the two holes on opposite sides of the corrector plate surround and unscrewing counterclockwise. Make a note of the corrector plate orientation with respect to the tube by marking the edge with a permanent marker or similar. Edit: Oooh! beaten to it. If it's like the ETX-125 the baffle was held in place by a ring of double sided foam tape which has now failed. You'll probably have to remove all the sticky stuff left on the baffle and secondary mirror. For the secondary mirror I used copious amounts of isopropanol.

Hi Shibby, yes I checked on a photography site and the DOF is stated as about 1m as you say. They use 'circles of confusion' as a limit for being in focus. I would have thought that a star would be seen as out of focus before the circle of confusion limit but the actual limit should hopefully be manageable. I did use the same star field for each test centred on Shedar in Cassiopeia as there are a mass of Milky Way stars to use as a test, 3000 stars on a 10 second exposure. I have tried it before and after a meridian flip and the tilt was the same in both tests implying everything was tight and not flopping under gravity. I've measured with digital calipers around the rotator and the Baader spacer and there was a slight error in spacing around their circumference of about 0.2mm in some tests. I think all the errors in all the spacers are on the same side at the moment so they're all adding up. The ball bearings arrived today so I can do a test indoors at about 10m to see if it works. The draw tube is only half way out at 10m so that shouldn't be too floppy when testing. Can't do it outside as pouring rain and 50mph winds for the next 24 hours. Alan

Glad it's now all working Jay. I wondered if you'd given up and it was all in the bin. The correct FTDI driver is built into Win 10 so you wouldn't have needed to download one. No snow here but very wet and cloudy almost all the time. Alan

Giving further thought, the centre of the board is closer to the scope than the corners so it will cause 'field curvature' of sorts. A curved board is too difficult to make. Tilt should still be visible though with the flat board. Squareness of the board to the scope could be checked by mounting the scope on a tripod and panning to the corners and checking they are the same focus. Alan

Thanks 'Stub Mandrel' that would certainly work, but I was hoping to let CCD Inspector do the hard work by analysing the 'stars' reflected from the ball bearings located at the crosses in my diagram. Thanks Peter, good point. My initial thoughts of a frame of perforated foil would certainly be tricky getting set up but the thick board with the ball bearings stuck on suggested by AKB would hopefully be easier. A plumb line would do vertical and a non-stretch line for horizontal might work. I don't know what the distance accuracy is needed at that distance to still be within the depth of focus at the sensor. Random would work AKB, but I believe CCD Inspector needs a good sample of stars in an area to get a good value on the actual focus. The 25 in the 100x100mm squares may still be too far apart for this. Randomly sticking them on would require lots more ball bearings to get a good density and the cost would shoot up. Spending £20 or so to make this prototype will I hope show if the idea does at least work. It shouldn't take too long to make and I certainly have plenty of time at the moment. main() { do { cloud(); rain(); wind(); } while (moon != blue); } Alan

Thanks newbie alert, but the video is using flat frames to centre the sensor whereas my sensor is tilted causing varying focus across the frame. Here's some examples using the 3D view in CCD Inspector as I was adjusting sensor distance to remove curvature by altering the Baader spacer and using the camera rotator to put the camera in the same orientation each time. The curvature is not bad in the last one but the tilt is awful and unpredictable, with everything done up tight. Here's a prototype diagram of the artificial star field at 1000 x 750mm size. This is OK at 20m for the ZS61 and ASI1600 (my initial calc was a bit off). I've ordered 500 5mm chrome ball bearings off ebay for £16.20 which seems a good deal and a large tube of black sealant to spot stick them down. The diagram needs 625 ball bearings but the 500 should tell me if it actually works and is worth pursuing. My initial thought of flood filling it with ball bearings would require 30,000 bearings. Does anyone know if the field flattener will still produce a flat field if not focused at infinity so that I could use the star field to correct curvature as well as tilt? Alan

Good idea, that seems a more practical solution. Cover the board with black silicone sealant and pour a bucket of small ball bearings over it. Spread them out and before the sealant is fully dried gently go over the surface with a cloth dampened with white spirit to remove any sealant on the top surface of the balls. It would be nice and rigid with a thick backing board, and as a bonus, when you're not using it to test your setup you could hang it on the living room wall as an art piece. Also you'd only need to cover spot sections of the board and not the whole surface to get a usable result but it might not look so good on the living room wall then. You could then use double sided black foam tape to stick the balls to the board. Alan

I've been having trouble with correcting sensor tilt on my ZS61 + FF + ASI1600MM. I thought it was due to the manual camera rotator which comes with the FF or the Baader variable T2 spacer. It's a lengthy job making adjustments putting it all back together slewing to a good star field, taking a few exposures, running them through CCD Inspector and repeating. The tilt seems to be random and doesn't follow any logic to the adjustments I thought I was making. The weather has been very poor for the past few weeks and I've managed just a few tests between the clouds in that time with no improvement. I was wondering if it's feasible to make a back lit board with some foil sheets in front covered in tiny pin holes to simulate a star field. At the FOV of 2 degrees the board would have to be about 2m across at a distance of 30m. I don't know whether the field flattener would perform correctly with non-parallel rays entering so it might cause field curvature, but I though the tilt error would still show the same using this method. It would be much easier having the scope on a bench looking at the board at the end of the garden and could be done during the numerous dull cloudy days. Does anyone have any views on whether this is a viable method. CCD Inspector doesn't require pin point stars, just ones it can measure the 'roundness' on. Alan

Jay, Unplug your FTDI cable from your Beelink and display Device Manager and select Ports (COM & LPT). You should see something like this. There may be extra Com Ports shown on your display (for focusers etc) but that's OK. With the above screen still open plug in your FTDI cable and an extra entry called 'USB Serial Port' should appear like this Note the COM port number next to the new 'USB Serial Port' entry. This is the number you need to assign in EQMod. On your EQMOD screen it's probably displaying COM error or similar. Click on the wrench icon as shown The EQMod ASCOM Setup screen should display as below. Click on the drop down box highlighted and select the same COM number you got from Device Manager. You might need to restart EQMod to get it to work with the new COM port. Hopefully it'll all work now. The Eqmod screen shots I got from the web and the layout is now slightly different. Good luck. Alan

I have a Beelink BT3 Pro Mini PC attached to my mount to control imaging from 2 scopes and have no trouble connecting to the mount using Eqmod with EQdirect. Are you using an FTDI chipset EQdirect cable. Device manager->Ports(COM &LPT)->ComX->Properties. The Prolific chipset EQDirect cables are a pain with Windows 10 as the built in Win 10 drivers won't work with them. FTDI chipset cables remember what COM port is assigned to it. Perhaps when you swap from your laptop to the Beelink the COM port the FTDI cable assumes it uses isn't available. Check the COM ports assigned on your laptop and the Beelink and ensure the ASCOM port assignments match for the software on each PC. I've never found the EQmod 'auto' COM port search function to work very well so have to check Device Manager to get the right one. Alan

The main reason I suggested having everything powered by a leisure battery rather than a UPS is it seems unnecessarily complicated and not very efficient to have during a power cut, a 12V UPS battery driving an inverter to generate mains voltage which can switch without glitches which then feeds a power supply to generate 12V which powers all the astro equipment apart from possibly a modest PC. A UPS is designed to power PCs for short periods only and not to generate 12V. A simple inexpensive float charger (constant 13.6V) connected to a leisure battery to power all your astro gear and a small inexpensive inverter to power a PC (if a laptop isn't available) achieves all you want. No problems with having to have clean switching, and no problems with extended power cuts that may last all night. A 12V battery is the best filter there is against power spikes, glitches and power supply noise. Alan

You're right Ray so you need to be careful. The Ctek 'Multi' chargers can be switched into 'Supply' mode so that it gives out a constant 13.6V to enable the battery to be used while connected to the charger to keep it topped up. It effectively forces it into 'float maintenance' mode. The battery needs to be fully charged using it's normal charging mode before switching to 'supply' mode as it's not the best way to charge a flat battery. Other charger makes probably have this mode too but I only have experience with the Ctek one. I should have explained it more in my earlier post. Alan

As most of your equipment is 12V you could run everything of a leisure battery with the battery permanently on charge using a Ctek charger or similar which won't overcharge the battery. If you have a desktop PC get a 240V inverter to run it off the battery all the time. It needn't be a large capacity battery if it's only needed for 20mins or so, but a 100AH battery you can still use it if your power is off all night. If it's a laptop then you won't need an inverter for a short outage. Alan

Yes, with the mount turned off just manually put it in the home position using the spirit level, setting rings as you prefer. Connect your eqmod cable and power on the mount and eqmod will assume it's in the home position, which it is, so all's well. Alan

I developed a large floater in one eye about 4 years ago (had smaller ones for as long as I can remember) and had it checked as it can be an indication of retinal problems but it was just a floater and was told to live with it as they are not treated under the NHS. A year later a similar one appeared in the other eye which made reading or using a computer very tiring as every time you moved your eyes my vision blurred as the floaters drifted past. I researched treatments and laser surgery had had some success with certain types of floaters so I paid for several sessions of treatments but to be honest it made little difference. I contacted an eye surgeon as to whether a vitrectomy (removal of the vitreous jelly in the eye) was a possible solution and he said it was if I was willing to pay for it. He said it's the only treatment that really works on removing floaters. I had one eye done and it was amazing having perfectly clear vision in that eye. I had the other eye done six months later so I'm now floater free. It's done under local anaesthetic as an outpatient and took about 45 mins. Three incisions are made in the white of the eye to insert three instruments, a light, an ultrasonic cutter incorporating a suction pump and a third tube to pump saline solution into the eye to replace the vitreous jelly as it's chopped up and sucked out, maintaining a constant fluid pressure in the eye. It's a bit uncomfortable while it's happening but that's all you feel. After a cup of tea and biscuits you're allowed home. The following day you go in to have the eye patch removed and given eye drops to put in for about six weeks. The only after affect from the surgery (apart from a very red eye for about two weeks) is the sensation of a bit of grit in your eye from the suture put in to seal the hole made for the cutter. The holes for the other instruments are small enough that they self seal. This sensation fades over a week or so as the suture dissolves. Hope that helps anybody who has wondered what's involved.