Al, further to Mike Snook's observation, these photos date from a little later then the Indian Mutiny period- and fairly clearly were not taken in India.
They appear to show two civilians, the left hand gentleman apparently a member of a rifle volunteer unit in the 1860s. His low, rigid bonnet indicates the early phase of the civilain Volunteer movement before standardised 'Scottish' military uniforms were adopted, most units favouring the glengarry bonnet as worn by the other subject. His doublet might be rifle green, given what look to be bronze buttons; the rank stripes on his sleeves are probably a gold colour, showing up dark grey as a result of the photographic process of the day. His kilt appears to have an overlay of white stripes( yellow stripes would also show grey-black). This might suggest a connection with the 78th Ross-hire Buffs, later The Seaforth Highlanders, whose military Mackenzie tartan was the Goverment sett with a white overstripe. I can't comment on the sporran. The low gaiters or spats of grey or khaki also reflect the Volunteer setting. The broadsword is a prop.
The second man, Cousin Alfred, is in formal Highland costume from possibly a little later, perhaps, say in the 1870s or maybe even the 1880s. From his broad, decorated sword belt and plain glengarry it is possible he was a piper. His clothing has no obvious military connection but examination of the insignia on his bonnet and on his belt buckle might reveal otherwise.
I hope that is of help.