Maybe it would be better if it was "the picture from" instead of "the picture of the party", because it could be a picture of someone who was at the party and not of the party itself.
And maybe a "photo" instead of "picture" for "fotka"?
A "picture" is a less formal version of a "photo" as well as "fotka", so I think "the picture" is ok. Probably, it would be even better a "pic". But anyway "the picture" or "the photo", it doesn`t change the meaning.