Thanks for your comprehensive answer re. image scaling. I've reflashed the firmware and there's no change in the System string. Could I trouble you to confirm that the latest firmware that you have for the 6510 is:
General_HZXM_IPC_HI3518E_50H10L_S38_RT3070_V4.02.R12.20150317_ALL.bin
and the...
Thanks for your help.
I had already installed the latest firmware linked from the page you gave
https://pan.sohu.net/f/MTY2NzYsaGRkaWQ.htm
Which is: General_HZXM_IPC_HI3518E_50H10L_S38_RT3070_V4.02.R12.20150317_ALL.bin
The build date shown in under Setting -> _Info -> Version talies with...
Let me start by thanking Don for this gold mine of information on these amazing little cameras!
I've searched the thread, but can find no mention from anyone about the dimensions / aspect ratio of the snapshot stills.
I'm using 4.0.2.R12.00006510.10010.1303 and the stills (704x576px 1.222:1)...