I often use photos to teach vocabulary but I'm not sure about the best verb tense to describe the events captured by a photo yet. If I use the present continuous and the photo contains some time reference to the past ( an event they know has happened in the past) this would be confusing. If I use the present simple, as it is often used by journalists to write photo captions, most students would think that this tense can be used to talk about events as they happen. How can I solve the problem and avoid misleading my students?

Thanks.