When I was photographing a theatre production recently, I had a quick conversation before the dress rehearsal, which went something like this: "Hi Robert, I'm the designer on this show - could you make sure you take some wide angle shots for my portfolio?"

Now, that's a perfectly normal, common and reasonable request - and one that raises an interesting question in terms of this sort of work: who exactly am I working for, or responsible to, when I photograph a show? And, how can I make them happy?

Well, it's not necessarily an easy answer - as (often) the only visual record of a show, there's a lot of responsibility on the photographer to document it for a range of purposes, many of which aren't mentioned or anticipated ahead of time.

Here are a few to consider, in order of immediate need:

• Social media, usually needed same-day or overnight;

• Print / web media, usually needed overnight to go with reviews the following day, or with preview articles if I'm photographing an earlier rehearsal;

• Advertising placement, ranging from newspapers to buses;

• Awards & nominations for individual performers, designers and / or overall production;

• Sponsor reports after a show has closed, & proposals for future shows;

• Pitch documents to venues or festivals in other cities / countries;

• Designers' portfolio use once the show has finished;

• Venue / festival management & technical producers' archival use and possible re-stagings in future - these can be vital for touring productions;

• Marketing use by the venue, suppliers or even manufacturers of equipment used by the show, as well as for tourism & promotion by the city / state / country where it took place;

• Future publication of the script in book / ebook form (for first productions of new plays);

• Future articles, histories, or biographies of the company, cast, director or designers;

• Archives and histories of the company, venue, city, and/or country where the show is happening;

Now, of course, some of these needs are overlapping - what makes a good publicity or poster image can also make a good magazine or book cover image - but what makes a good social media image can depend on whether it can be cropped to a square, and whether the image is tight enough to be strong at a small size when viewed on a phone, rather than the back of a bus. (Which is pretty much the exact opposite of what the designer needs, for their portfolio!) And what works for a Facebook cover image often doesn't for a magazine cover in print. Plus, if specific companies have provided product for the show, images of those in use may be needed - props, hats, shoes, flooring, paint, you name it.

So: how to prioritise between these many, varied and often contradictory needs, at any moment?

I try to approach a production like a cinematographer might:

Taking that approach usually makes sure I have what cinematographers call 'coverage' for all the many possible needs, a varied range of images from a production, and images that both document and glamorise the show.

But to answer the big question - who am I responsible to? - to me, the real answer is history.

Whatever I'm doing, however I record a production, that will quite likely be the main visual record of how the show happened. Where, when, with who, how it looked, how the lighting changed over the course of time, all of it. So, while of course the immediate needs are for social media, marketing and PR, that too is creating the history of the production. If it sells well, if there's a buzz around it, it gets talked about and written about; and that makes it historically significant.

So maintaining my archive of past production images also becomes vitally important, as often these future needs don't become clear immediately, and often the photographer is the one taking the most care to guard their digital archive.

Image files get deleted or lost, hard drives crash, companies change, fold, or move on - things happen, and valuable archives can turn into an old second-hand drive that doesn't work any more very easily. (Remember when people used to deliver image files on CD-ROM? Can anyone access those any more - and, is the data on them still intact?)

But, perhaps that's a topic for another day...

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