When an Indian sneaks into the Fort at night and stabs a guard he is chased out of the Fort by the Captain and lieutenant. The Fort has a big iron spiked gate that the groups enter through in several shots and yet the Indian attacker enters the compound over a short fence they all jump over.
Night scenes were filmed in daylight hours using a filter to darken the scene. But this technique fails to make daytime appear to be nighttime. The sky is usually either bright or blue and the night sky is always black. Further, distant objects are fully distinguishable with great detail (as they are in full Sunlight), whereas at night they would completely disappear into shadows or darkness.
When there is a party for the engagement there are a number of senior officers in attendance but the fort has only the Captain and the three young lieutenants so where did all these older and over dressed officers come from?
On the night before the final battle: around the campfire, bottom right, ribbed shoe-prints are clearly visible in the dust. They were obviously made by modern footwear with synthetic soles.