Rob,
It is certainly possible that some of the photographs were taken on the 17th, 18th or 19th. Looking at the the landscape in the selection I have posted, it seems to me that the images were captured at at least three different locations. However, it is difficult to know which shots were taken when.
Reading Dickson's account of this period, it appears he did not film the guns on the post-Colenso dates. The 17th was so unbearably hot that his team hardly left their tents, and the 18th was spent in Durban, ensuring that the footage already captured was safely loaded onto a Castle Line steamer bound for England. He briefly mentions the destruction of the wagon bridge on the 19th, but does not describe any filming. I therefore suspect the photographs that include the Biograph camera were taken on the 13th or 14th, and most probably the 14th, as correspondents (apart from Dickson) were barred from attending the bombardment until after firing had pretty much ceased at noon that day. This would explain why the Naval Brigade are stood down in these shots:
"After the shooting was all over and things comparatively safe, a stream of war correspondents could be seen making their way towards us from Frere Camp".
The photograph you posted was taken from the exact same spot as the first image in this thread, which includes Dickson's camera. Burleigh's presence in the latter shot again suggests that it was taken during the afternoon of the 14th, once the press corps had at last been released from the bounds of the camp perimeter, and after the shooting had all but ceased. The grey overcast weather also fits with Burleigh's observation that, unusually, "Thursday broke raw and cold".
The ground upon which the guns were placed for the actual battle is described as a slight rise, which indicates that those images showing the 4.7s on the tops of hills were not taken on the 15th. Indeed, I suspect none of the photographs show the guns in action during the main engagement.
This is what watching the actual battle looked like (Pakenham, p. 119).
Here is a photograph showing the result of Lieutenant England's "fluke" shot. It is noteworthy that Burleigh, unlike those writers with allegiance to the Naval Brigade, states:
"Excellent as the weapons of the bluejackets are, their shooting is not always what it ought to be".
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