Aargh! Multiple set-up issues

[Padraic M]

I had a very frustrating time last night trying to set up for imaging. Nothing worked for me! Hard to know where to even start to resolve the various issues. Here's a summary. I will open separate threads on each of these issues as and when I get the time.

The purpose of setting up last night, even though the forecast was only so-so, was to test out guiding on my HEQ5 Pro, having just astrobaby-tuned it, and before I install the Rowan belt mod. Problems:

1. The weather. Nothing any of us can do about this I suppose, but the actual weather was a harsh interpretation of the CO forecast to say the least. I found myself at 2am trying to decide which was better - rain damage or mechanical trauma - as the night was getting very blustery with a few drops of rain. Eventually got sense and decided to risk neither, and had a realtively early night with no results to show. @Gina is currently working on a read-only weather station. I've no doubt that when she has that done she will do a version with full update functionality so we can actually change the weather conditions at will.

2. The HEQ5 Pro mount, post astrobaby strip-down and tune-up. Certainly no quieter than it was before; a noticeable ~2mm of play in the RA axis once loaded with scopes and cameras. All obviously not well from the start. Sharpcap polar alignment worked fine, with Excellent PA result. However, Phd2 considered PA to be 13.2 arcmins. Seriously? But then, phd2 errored 'Unable to move mount in RA....' so guiding was not possible. Worth adding that manually the RA axis moves very smoothly with the clutches off, or with the Synscan handset. I can also control it fine using the scope controls in APT, so mechanically it's working, and the connection to mount is working. 

Could the excess play in RA be preventing guiding? Testing today in daylight suggests that the worm gear alignment was at fault; the RA worm shaft float adjuster was loose.

3. Had some head-scratching minutes trying to sort out my camera until I noticed that APT had automatically connected to the guidecam (290mc) instead of the imaging camera (1600mm). Used the name of the imaging camera alright, but the sensor dimensions were obviously from the guidecam. Resolved this by reconnecting until the imaging camera was selected. No problem cooling to -20C.

It looks like APT's CCD 1 and 2 slots are being allocated 'randomly' to the two cameras; so while I can set APT to always connect to camera 1 or 2, is there a way to consistently allocate the camera numbers to specific cameras? Otherwise, it's hit and miss every time.

4. Focus. I installed the Celestron electronic focus motor on the C8 SCT recently. Didn't realise at the time that you lose all manual focus capability with this focuser unless you have a Celestron mount handset. I couldn't find any out-of-focus star to start the autofocus routine, no matter how hard I searched. Pure black image with each capture, with the odd completely white image. Spent ages focusing with small steps to try to find a donut somewhere, but failed except for one short period. I now think that the camera connection was not working for some reason, and I was not getting an image at all. No errors reported from any part of the imaging chain.

I didn't manage to get focused before the clouds rolled back in, so had to finish up for the night. I wish I'd gone for a PLL ESATTO, although they're very pricey, but at least I would have coarse focus under manual control. Has anyone made a focus hand controller for the Celestron SCT focus motor?

I can't reproduce this today. I'm working on the assumption that there is USB contention somewhere along the line; my hub is USB2.0, but the ASI1600mm imaging camera is USB3.0. Always worked before, but with imaging cam, guide cam, focuser, mount and efw all on the hub, maybe there's too much traffic.

5. Mount LED flashes when the mount is slewing. I noticed this previously but hadn't paid much attention to it, although it didn't seem right. I did some experimentation with it today and unfortunately I think I have a power issue.

I have a 10A 12V power brick with a cigarette socket output. I also have a 4-way cigarette splitter, so that I can power the mount, camera cooler and dew heater. 10A should be plenty of juice for that combination. If I connect the mount only, directly to the power brick output, the input voltage as measured by the handset is 11.4V. When slewing both motors, it drops to around 11.2V, and the LED stays on constantly. If I connect the mount through the 4-way adapter into the power brick, the voltage drops below 11V, and the LED sometimes drops out. Lastly, if I also connect the dew heater to the 4-way, the voltage drops down to 10.5V and the LED flashes like a Christmas tree.

This isn't a mobile setup, so the power brick is plugged directly into the mains. Any suggestions on how to power such a setup? I'm assuming that I will need to power the mount directly from mains with a separate 12V converter.

 

Apologies for the long rant. Any or all suggestions on these topics greatly appreciated!

[bottletopburly]

I have a 10A 12V power brick with a cigarette socket output. I also have a 4-way cigarette splitter, so that I can power the mount, camera cooler and dew heater. 10A should be plenty of juice for that combination. If I connect the mount only, directly to the power brick output, the input voltage as measured by the handset is 11.4V. When slewing both motors, it drops to around 11.2V, and the LED stays on constantly. If I connect the mount through the 4-way adapter into the power brick, the voltage drops below 11V, and the LED sometimes drops out. Lastly, if I also connect the dew heater to the 4-way, the voltage drops down to 10.5V and the LED flashes like a Christmas tree.

 I have 13.8v on my pier your not getting enough juice .

 

 

 

 

 

 

 

 

 

 

 

i

[Merlin66]

Suggestion..

One power brick for the mount say 5A or 10A and fit a 120w car convertor 12V -15V setting. This gives a target 15V at the HEQ5 mount and also maintains >12V. No more flashing red light issues.

Use a second independent brick for the cameras (no need for the additional convertor) and finally a third brick if you use dew heaters etc.

I use a 10A set-up for my mount (NEQ6pro) to run everything (no dew straps) - no issues.

[Padraic M]

@bottletopburly and @Merlin66 thanks guys, yeah I thought so, time to beef up. I suspect my ebay power brick isn't quite as advertised. Difficult to source 15V 10A converters. 

[Padraic M]

Huge Nevada 13.8V power supply on the way! 10A through the cigarette socket, can supply up to 20A in total. That should be enough!

[Padraic M]

This chap arrived today. 10A through the cigarette socket, up to 30A out the back. With all equipment connected, mount slewing in both axes, three dew straps on, camera cooling to -20c, I'm drawing around 4A. Voltage output stays solid at 13.8V.

The handset on the mount shows 12.8V at rest, down to 12.5V when slewing. No more flashing leds, and a nice bright orange handset backlight!