heh, that Canadian looks like a big lad - he's practically towering over the two Brits :evil:
Anyhow, yeah, those are precisely the sort of photos I look for; official photos are all well and good, but as you say, they tend to be staged, and as a result, tend only to show what the official line is (normally at the hands of the relevant units' RSM!): Personal photos (which I primarily look for, along with news photos, for the same reason) are not normally posed with such an emphasis on correctness of kit, etc, and for that reason give a better idea of the actual situation at a given time.
You can, as you can see, with a little thought and knowledge, tell a heck of a lot from such photos...
Your photo, for example, shows the two Brits wearing different kit - the lad nearest the Humber Pig (I thought it was a Champ at first, but note the angle of the roof!) appears to be wearing BD trousers (note placement of leg pocket), whereas the lad in the foreground (who I think appears to be wiping his hands on a cloth or bar of soap) appears to be wearing 60-pattern trousers (leg pocket and belt loops refer); both are wearing headovers, which most troops hate, so I'd hazard a guess that they're playing "red forces" (later exercises, such as Lionheart in the 1980s, renamed that into "orange Forces" as while it's alright to use all manner of nastiness in killing the enemy, you can't call it rude names, oh no :nut:).
I also notice that they've gone well over the top in camouflaging their Pig - it's a veritable wheeled bush! Just look at all the foliage on the top and sides!
Anyhow, thanks for the photo - it's useful in showing the changeover from BD to OG in the early 1960s