1. What does it mean?
홈마 abbreviates 홈페이지 마스터, homepage master. In fandom it commonly refers to someone who runs a fan-focused site or social account and regularly photographs an artist at events, rather than a general website administrator.
Also written or said as 홈마스터, homma
2. The nuance
The label does not make an account official or grant permission to photograph anywhere. A 홈마 and a 사생 are not synonyms; privacy-invasive behavior is a separate issue.
3. Examples
“홈마가 올린 공연 사진에서 조명이 잘 보였어.”
The concert photos posted by the fansite photographer captured the lighting well.
“그 홈마는 사진 재업로드를 허용하지 않는대.”
That fansite photographer says reposting their photos is not allowed.
Sources
References support the meaning and usage. Example sentences are written for NoCapWiki.