Which goes where...confused about wiring....

[Gina]

1 hour ago, SkyBound said:

Well all I know is that 12v DC supplies for these cameras, were available, and came with crocodile clips for battery connection, so I guess it is possible to do..!

Yes, it's possible to do if you're familiar with electronics but it isn't easy.  There may be ready made units out there that do it but I can't find any.  Maybe someone else knows.

[Gina]

I have one suggestion.  Since the -12v only needs 100mA you could use a separate battery to supply that.  It wouldn't need to be anything like as big as your main battery.  There are plenty of small 12v rechargeable batteries available.

[RayD]

Unfortunately you would definitely still need the -12v on pin 4.  The DC ground is 0v which is why the "-5v" (actually 0v) leg of your DC-DC convertor gets put here.  If you don't have a regulator, which is what I'm assuming their 12v power supply is, then I  don't think you'll achieve this very easily from a battery alone as it would need a voltage divider circuit to get the -12v.

Your pin configuration in your plug as per that table is correct, but the supply to it would still need to be as the pins suggest, with the -12v actually being -12v and not 0v.  As Gina notes, you would only have +12v on pin 2 with respects to common, but would have +24v with respects to -12v on pin 4.

iI guess it's a little bit like the yellow site transformer boxes which are 110v centre tap, so only 55v per leg with respects to earth so reduced risk of shock.