I live in Camberley and drive along that part of the A30 daily.
I am inclined to the view that the pic is contrived.. Asa has been pointed out the aircraft is some way beyond the famous (well locally famous) white elephant and would be over the A331 dual carriageway just south of the Meadows roundabout. Neither there back in the day. If you were headed west from the point where the picture was taken you drive mostly up hill until just short of the airfield which suggests the DC8 would be very close to the ground very quickly.
Also the weather is poor and at least today anything of any size going into Blackbushe usually joins the extended centre line a mile or more back over Camberley so to me unless the DC8 crew are really having a risky business day I have doubts about the picture . I mean did airline pilots back then really look to make 40-50 degree turns 1.5 miles from the runway in bad weather with slow to spool up first generation Prattt and Whitney JT3s at an airfield they had almost certainly never seen before with a runway of very marginal length for a dc8??