[2] According to the history of the Ray family, one of their ancestors, Shri Ramsunder Deb, was a native of Chakdah village in Nadia district of present-day West Bengal, India.

He became an eminent expert in interpreting old land deeds written in Persian and in helping the landowners get the best deal from the newly introduced British legal system in India.

[10] In his own lifetime, a printing expert from abroad commented that Upendrakishore's contribution was far more original than that of his counterparts in Europe and America, "which is all the more surprising when we consider how far he is from hub-centres of process work".

Even the building plans were designed by him [13] He quickly earned recognition in India and abroad for the new methods he developed for printing both black and white and colour photographs with great accuracy of detail.

It was with the intention of running this business that his son Sukumar Ray spent a few years at the University of Manchester's printing technology department.

[10] In his own lifetime, a printing expert from abroad commented that Upendrakishore's contribution was far more original than that of his counterparts in Europe and America, "which is all the more surprising when we consider how far he is from hub-centres of process work".

[11] He invented several techniques related to halftone blockmaking, of which the "screen-adjusting machine" for the automatic focussing of process cameras, was also assembled in England following his design.

[13] The British handbook of printing technology, the Penrose Annual, Volume X, 1904–05, mentioned about him in an editorial note that, "Mr. Ray is evidently possessed of a mathematical quality of mind and he has reasoned out for himself the problems of half-tone work in a remarkably successful manner ... (His printing developments) enable the operator to do uniform work with the fullest graduation and detail in it and with the minimum amount of manipulative skill in the negative-making and etching.

He further wrote Gupi Gyne, a fantasy novel (later adapted into the film Goopy Gyne Bagha Byne); essays like Daasotto Pratha (regarding slavery in the United States), Sandow (on Eugen Sandow) etc and travelogues like Puri, Abar Purite (on Puri, Odisha), Megher Muluk (on Darjeeling).

These were published by Dwarkin & Son, which was a famous music firm of the times, established by Dwarkanath Ghose, the inventor of the hand-harmonium.

[15] Upendrakishore's eldest daughter, Shukhalata Rao, became a social worker, children's book author, and editor of a newspaper, Alok.

She founded the Shishu-o-Matri Mangal Kendro (Centre for the Welfare of Children and Mothers) and the Orissa Nari Seva Sangha.