Thanks for the confirmation that it is a power problem. I realized that I hooked it up in the wrong order. I connected a powered hub to the computer and then connected the daisy-chain of extension cables between the hub and the camera, figuring it would at least start out with lots of power. I can see though that the powered hub would be much more effective at the camera end of the extension cables.

I was noticing on USBgear.com that there are some extension cables with various ways of providing power at the far end. One of them is set up with a B end on the cable to plug directly into the hub. Another has a second male USB connector for power. I was also thinking that I could rig up a separate heavy-gage 5V DC cable to run along with the USB cables and splice it in at the end, but it might be easier to just run 110v AC out there to power a hub.

OK, so here is how I ended up getting this to work: I am now running a Logitech Orbit/Sphere MP 16 meters (48 feet) from the computer. I have a powered Linksys hub connected to the computer with the 6 foot wire to the hub through the wall of the house to a large j-box outside to hold the hub. Then I have a 36 foot active A to B USB-2.0 extension I got from USBGear.com plugged into that hub. The active extension has the active electronics in a little pod about half way along the 36 foot cable. That cable must be used to connect a powered device at the far (B) end, so it is plugged into a second (cheap off-brand) mini-hub with a second power supply in another j-box (mounted near the bottom of the tree on which the webcam is mounted). Of course, that meant I had to run 110v AC out to the tree to power the hub's power supply. I tried a different hub with a smaller power supply but I kept getting a message saying there was insufficient power to the camera. There is a 6ft passive USB extension cable plugged into the second hub, and then the camera is plugged into that passive extension. It has been running just fine that way for a couple of weeks without any problems. The picture from the camera is online & listed here on AbelCam ("View From The House At Sunset Trail") during daytime in the US Central time-zone when it is light, or go directly to the webserver at http://sunsettrail.no-ip.biz:8080. The MP is on the long extension. If you pan the MP to the right and tilt up, you can see the side of the house with the gray j-box where the cable penetrates the wall, just above the bend in the rain downspout. You may be able to just make out some of the cabling running down alongside the downspout. Then the cable runs along the ground to the tree and up the tree to the webcam, about 12 feet above ground (mounted in a home-made weather proof enclosure). Power for the hub in that upper j-box comes through the wall with the USB cable. Power for the hub on the tree comes from the outlet box you can see on the side of the house down below the red siding.

So, in summary, the web cam is on the far end of this series of stuff:

1) Linksys powered hub with 6 ft cable.

2) USBGear 36 ft active A-B extension

3) Off-brand powered hub

4) 6ft passive extension

5) MP camera's own cable.

Of course, your footage may vary and results may not be typical, but it is working so far. The powered hub at the far end near the camera seemed to be the key to getting it to work.

It only seems to run 2 to 3 frames per second, but I think that is a problem of the slow computer to which it is connected rather than the cabling. It doesn't do significantly better on a shorter cable.

p.s The second (AF) webcam is mounted in the upper (dormer) window visible in the picture from the MP. If you switch to the AF and pan to the far left and down, you will see a branch of the tree on which the MP is mounted, but the trunk of the tree with the webcam on it is just out of sight farther left than the AF can see before it is blocked by the eaves. The AF mainly looks toward Chicago from the Lake Michigan south shore. The large field of white at the moment (Jan 7, 2010) is Lake Michigan iced over out to the horizon. The AF runs on one 16 ft active USB-2.0 extension cable connected directly to the computer.

The moderator on the Logitech webcam forum suggested yesterday that the low framerate may be due either to having more than one camera on the same USB controller, or to having them connected to a low speed usb 2.0 port instead of a high speed usb 2.0 port. Until he said that, I never knew there was such a thing, but he says most computers have 2 or three usb 2.0 controllers, but that only one of them is usually high speed. He said that to get the best speed, I should get an add-on PCI high speed usb 2.0 controller card and make sure the cameras are on different high speed controllers. I'll have to look into that.

Also, since yesterday, I added a third camera, which is one of those binoculars with the digital camera built in. I have it aimed across Lake Michigan at Chicago (about 30 miles away) and on a clear day the Chicago skyline can be seen. I think it's snowing at the moment, so it doesn't show much right now. It is not a ptz camera, but I have it set up for virtual ptz.