[Wade]

sanjay, in the case of prefixes, like un-, it is generally accepted in most
writing style guides that if the word you want to combine the prefix with has
not yet been formally accepted by the "community of speakers/readers/signers"
with the prefix on it (i.e. it is not yet in the dictionary), you can still
use the prefix with the word, but hyphenate it to indicate that you have done
just that.

So the short answer is just write "un-photogenic."

--Wade
[no Ph.D. in Linguistics]

"sanjay" wrote:

what is antonym of photogetic? unphotogenic is not a word.