Camera stuck at "Reading"

[Mike Dodd]

I'm continue to have problems with my camera. Sometimes MaxIm won't download an image after an exposure, and gets stuck at "Reading." I bought a new active USB 3.0 cable, and have tied-down all the cables to the camera so there is no way any strain is placed on the connectors during mount movement or camera rotation.

The only thing I can figure is that something in the camera is affected when the Pyxis rotates the camera. Vibration, maybe? Perhaps it's time to open up the camera and apply some conformal coating to all the electronics, like I used to do for some mil-spec stuff I built years ago.

The problem has occurred twice on the first exposure after the meridian flip. So I'm thinking I will not rotate the camera 180 degrees after the flip.

Question: If I do not rotate the camera after the flip, will ACP frame my target so it matches the east images, only upside-down?

If so, I'll omit the post-flip rotation, and rotate the west-side images during processing.

Thanks for any information on this.

--- Mike

[Colin Haig]

Mike, I think you are barking up the wrong tree, and DO NOT put coating on the electronics.

There should be enough heat in the camera to keep any moisture off, and this isnt behaving like a moisture problem, this is behaving like a USB problem.

You need to go about this step-by-step, methodically. Process of elimination.

Start by posting a photo of your whole setup, showing how you've run the cables and secured them.
It could be as simple as the camera power cable and USB cable is flexing and disconnecting/reconnecting during movement.

Take a short, passive cable, and connect the camera to the PC on the "workbench".
Download 100 images or so in MaxIm on its own.
Once you know that works, turn the camera over - and then run test again. Will simulate your rotation.
There is no vibration during the rotate as the camera isnt doing anything but cooling.

Make sure you have turned off Windows Power Management - USB Selective Suspend on the USB Root Hubs, the USB Hubs, and that includes the USB 3 extender cable. And any devices such as serial power / usb adapters etc.

Suggest you also download Microsoft USBView and make sure that the camera is not sharing a USB bus with other devices.

I looked through a bunch of your threads and could not figure out which camera you have. Which is it?

If it's a ZWO ASI 1600, get the latest ASCOM driver for it as there are fixes for that camera - v1.0.3.22 and the camera driver v3.0.0.5.
Also, for ZWO, lower the USB bandwidth to 40%.

Good luck.

[Mike Dodd]

Start by posting a photo of your whole setup, showing how you've run the cables and secured them.
It could be as simple as the camera power cable and USB cable is flexing and disconnecting/reconnecting during movement.

Exactly my thought when I tied-down the cables last night. I think they're immobile now. I have attached a photo.

Take a short, passive cable, and connect the camera to the PC on the "workbench".
Download 100 images or so in MaxIm on its own.
Once you know that works, turn the camera over - and then run test again. Will simulate your rotation.

I'm currently taking hundreds of 1-second images with the camera on the OTA, at the end of the new active USB cable, and rotating the Pyxis while exposing. It's performing perfectly (except the first image; see *** below).

Make sure you have turned off Windows Power Management - USB Selective Suspend on the USB Root Hubs, the USB Hubs, and that includes the USB 3 extender cable. And any devices such as serial power / usb adapters etc.

Thanks for the tip. I did it, and that might explain why it's working so well now.

Suggest you also download Microsoft USBView and make sure that the camera is not sharing a USB bus with other devices.

I will look into that later today.

I looked through a bunch of your threads and could not figure out which camera you have. Which is it?

ZWO ASI1600MC Pro.

If it's a ZWO ASI 1600, get the latest ASCOM driver for it as there are fixes for that camera - v1.0.3.22 and the camera driver v3.0.0.5.
Also, for ZWO, lower the USB bandwidth to 40%.

Just checked and, yes, I have both of those installed.

*** I wonder if my camera is defective. I powered-up the observatory this morning, chilled the camera, and began taking 1-second exposures. Maxim displayed Reading for 4-5 seconds before actually displaying an image. Worse (as I determined after 400 images) the image was the same flat frame I exposed last night before shutting down! It was only after I disconnected/reconnected the camera were the images current. I can check this by switching the light box on and off while the images are exposing. Now Maxim instantly downloads each image, with no Reading displayed after an exposure -- only a very brief Downloading. I think it's time for another email to ZWO (my sixth in this saga).

[Bob Denny]

One thing to try for diagnostic isolating problems is to turn on (checkmark visible) "Disable Slew During Image Download" (ACP Preferences, General tab). This uses a different (synchronous) read/download process in MaxIm.

[Mike Dodd]

One thing to try for diagnostic isolating problems is to turn on (checkmark visible) "Disable Slew During Image Download" (ACP Preferences, General tab). This uses a different (synchronous) read/download process in MaxIm.

Welcome back, Bob. I hope you enjoyed your family visit.

I now believe the camera is defective, and I am in email contact with an engineer at ZWO in China. He asked me to run a few tests, which I did yesterday.

MaxIm downloads images fine at ambient temperature, at 0C, and at -20C. The problem occurs after a 180-degree camera rotation at -20C (only). It does not occur after rotating with the sensor at 0C or ambient temperature -- only at -20C.

The mount is parked and powered-off, and ACP is not running -- just MaxIm alone.

After looping and tying-down all cables to the camera, there is no chance that rotating the camera puts any strain on any cable connected to the camera.

I suspect (and so does the ZWO engineer) that there could be a cold solder joint inside the camera. He wants me to do one more test using ZWO's ASICap imaging software, and tapping the camera when cooled to -20C vs. rotating it. I will do that tonight or tomorrow when the rain quits. I also will do this same test with MaxIm, since that's where the problem occurs, and is the program I must use with ACP.

Another part of the problem is that sometimes, when MaxIm does download an image, it is the previous image! Yesterday, I was imaging my light box when the problem occurred. I switched the light off and on during the 1-second exposures. After each exposure, MaxIm displayed "Reading" for 8 seconds, then downloaded the same light-on image every time. Very strange.

The camera has a 2-year warranty (bought new in July), and ZWO has been quite responsive. They even asked me where I bought it. Sounds like they're planning for an exchange.

...a different (synchronous) read/download process in MaxIm.

Is there a way to set this mode within MaxIm, independent of ACP? Might be worth a try.

--- Mike

[Bob Denny]

Is there a way to set this mode within MaxIm, independent of ACP? Might be worth a try.

No, MaxIm always uses the synchronous read/download mode. The asynchronous mode was put there by Diffraction waaaaayyyyy back in the beginning so ACP could overlap slew to next target with download last image of current target.