During my webinar yesterday for Findmypast - which I must say I enjoyed very much - I showed a slide which I called "A tale of two sergeants". I showed the two images above and below of two different seregant in the Royal Sussex Regiment. The photo above dates to between 1881 and 1902 whilst the one below dates to between 1902 and 1913, and probably to between 1911 and 1913 when the 1st Royal Sussex was stationed at Rawalpindi where this photograph was taken.
The sergeant wears - I believe - a serge, five-button tunic and the white piping around his collar tab marks this as a tunic no earlier than 1902. I also made pointed out that from 1913 the shoulder tabs were white. I didn't illustrate this in my slides but do so now via the Harry Payne illustration below. The solider here is an Essex Regiment corporal - and marksman, to boot - and wears the QSA and KSA on his left breast. He wears a seven-button 1902 pattern tunic with the pointed cuffs; very different from the jam-pot cuffs seen on the uniform of the sergeant in the first photo.
The Essex Regiment - an English infantry-of-the-line regiment -wore white facings, unlike the Royal Sussex Regiment which, as a "Royal" regiment, wore the blue facings. Note the thin red stripe on the Essex corporal's trousers and compare this with the thicker red stripe seen on Royal Artillery and Royal Engineers' uniform.
I research soldiers!
Contact me if you need help with your military ancestor.