Yes they can be though I'm not good with uniforms of the Imperial Service Troops. Some are in field service dress others in ceremonials. Every subject painted by AC Lovett normally has their signatures at the bottom of the painting. A friend has an original painting of his GG father done by Lovett.

The colours on this copy of the book on archive,org are darker and duller than the original paintings. Most of the colour plates are also on The National Army Museum's website and the colours there appear to be truer. http://www.nam.ac.uk/online-collection/results.php?searchType=simple&resultsDisplay=list&simpleText=lovett

Sushil Talwar are these parade or battle uniform and can you identify each ?

Thank you for the link. Useful share.