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[disaster]

So I'm now resolved to the fact that my 920 will disconnect a few times a day no matter what I do.

But I think the disconnects last less than a minute each & so my system availability is above 99%.  Actually quite good for a budget system.

Anyway I started playing around with the image & frame choices.  I had left things in the default mode & was trying to solve a focus problem by using the lens ring.  Didn't know about the pixels.  Changed from 320x240 to 640x480 & wow, much sharper image quality.  Solved the focus problem.

Unfortunately the video quality suffers at the higher pixel counts.  The video isn't as smooth as with the lower pixel count.  I'm playing around with frame rates & "image quality" but haven't really found a compromise I like.

At 30 fps & 640x480 I get video that is almost smooth, but not quite.  When someone walks through the scene their little legs are constant blurs - like little floating bodies floating above colored blurs.  In auto fps & 320x240 their legs actually show smooth motion & look like legs moving - whole people walking.  They just aren't in sharp focus.  I'm told that 70mm motion picture video is based on 24 fps so I would think 30 fps would give similar results.  I believe that 640x480 should be "interlaced" images (not sure though), which is supposedly Superior for video.  Since the images are MPEG I'm assuming MPEG2 or 4 which are supposedly superior for video images.

So it seems a paradox: sharp image & questionable video OR fuzzy image & smooth video.  How can I solve this?  Or is this just one of the limitations of digital video?

Thanks for your help.

[Mackerel]

I solved this by going wired. The actual max speed on 640x480 is 20 fps...
When going at that rate you will expect something like 4.5 Mbps per camera. Wifi cannot take that kind of punishment when connecting multiple cameras, including inter-camera interference when placed near enough to each other. But when using it wired you can get quite a quality stream at 20 fps. Cars zipping by and legs are good, unless it gets a little dark.

[disaster]

Thanks for the reply.  Unfortunately wired isn't an option for me.  I have to go wireless.  I'm only using a signle camera for the moment, I plan more as I figure things out.  Currently I'm getting data rates in the 4+ Mbps, so that agrees with what you're seeing.

You say that the wireless rate just isn't up to the frame rates.  Bummer.

My Router claims upto 300 MBytes/sec.  I'm assuming that's per link, not the combined total.  Since it's a Gigabit ethernet router that seems to make sense.  It supports choices of 54, 130, & 300 MBytes/sec for wireless.  I think I have it set at 130 currently, but I should check.  I was fooling around trying to fix the disconnects so I'm not sure where I left it.  I also have 2 independent channels in the router - one 2.4G & another at 5G.  Since my only camera is at 2.4G that's where I'm operating.  As I add more cameras I'll have a mix of both 2.4 & 5 so I'm hoping that the data rates won't be a problem.  I will probably connect the PC to the router with Gigabit Ethernet which will tripple the 300 Mbyte/sec wireless rate.  Still lots of data transfer, but I'm hoping my little network is up to the task.  The data rates will limit the number of cameras I can support at the higher bit rates though.  Realized that when I started this little experiment.......

thanks for the reply.

[Mackerel]

The 920's only go up to wireless-g, so 300 Mbps is not there. Only at wireless-n (930 can do that theoretically)...