Steve Finn asked: As an aspiring writer, I'm becoming aware how important images are so am getting more serious about photography. For print media, what is the accepted minimum resolution, size and format for publication?

Doug says: The answer is, bigger is better. And the reason is because if you are shooting digital a large file size will allow more flexibility for different image applications. Currently there are a number of digital cameras on the market in the eight megapixel range. This will produce a file around 22 megabytes at maximum resolution, more than big enough for newspapers and even usable in some magazines. However many picture libraries are now demanding that digital photographers produce pictures of at least 30 megabytes, which translates as an 11-megapixel camera. Apart from a bigger file the major difference here is cost.

An eight megapixel single lens reflex (SLR) camera can be picked up for under £500 usually with a lens, whereas an 11-megapixel SLR will be at least three times that price. So you have to ask yourself what will be my primary picture needs and what kind of equipment will fulfil those needs.

For writers wishing to shoot their own digital pictures it may not be necessary to buy the most expensive gear available, but what will be necessary however is that they shoot with the same rules in mind as a professional snapper. That means using equipment that will allow the photographer to shoot in a variety of different file extensions -primarily Jpeg and Raw (which will convert to Tiff on the computer).

A Jpeg file is a compression file, meaning that the camera weeds out information and therefore allows files to be reduced when closed. The advantages are that they take up less space on storage cards and are easier to transmit along phone lines. The disadvantages are they are unlikely to be used for magazine applications or advertising purposes.

A RAW file is a non-compression file. The camera gathers all information, which allows for maximum usage of the image. The disadvantages are they are big and therefore take up a lot space on storage devices, are slow to download to the computer from the card/camera and take more time to manipulate in the computer. The advantages are they have the most flexibility when it comes to usage and produce better pictures. For travel photographers, always shoot in RAW, if for no other reason than to try to take advantage of other sources of revenue for your pictures.

Picture libraries are a key source of images for all print media and the advertising industry. Even if I were primarily a writer, I would still be thinking about the libraries. Once your pictures are used for your story why not see if they will be accepted in a stock library. They may not make a lot of money throughout the year, but I can guarantee it will be more than the file cabinet drawer in your office.

There are a lot of libraries out there, and all have different rules when it comes to prospective contributors. The British Association of Picture Libraries and Agencies (BAPLA) produces an annual book that lists all picture libraries in the UK with full details on what kind of images each library holds and full contact details including websites (www.bapla.org). In my opinion, this is the first place to look if when I want to make my pictures work for me beyond a single story.

The next question to ask yourself, if you are shooting travel pictures for publication, is when I've shot all those RAW files where do I store them when I'm on the road. First, never carry just one storage card - always have at least two. The main reason is that if one gets corrupted - sand, moisture etc - then you'll have a back up. Card prices have dropped in the last year, so make sure your memory cards have at least one gigabyte of space, especially when shooting in RAW. Still, memory cards are often not enough. I use rechargeable handheld hard drives for backing up my files while I'm working. There are a number of manufacturers - Vosonic (www.vosonic.co.uk), Jobo (www.jobo.com) and Epson (www.epson.co.uk) - all making mini hard drives with a combination of features and a variety of prices. The key things to look for are the size - around 40 gigabytes each - and that it can record RAW files.

When all of your RAW images have been captured, rendered through Photoshop and saved at maximum size tiff files at 300dpi, then it is up to the individual publication to ask for a specific image size. For instance, a newspaper will often ask for files no bigger than 10-15 megabytes at 300dpi, but will also want them as jpegs. That means saving a copy of your tiff as a separate jpeg. On the other hand a magazine may want the exact same image, but as a tiff and as big as you've got. So you need to be flexible - shoot in Raw, save as tiff and convert when necessary.

What we have been discussing here is all to do with digital photography. Don't think film is dead. Many magazines still prefer to use pictures captured on transparency film and then scanned on a high-resolution drum scanner. However that's a discussion best left for a later date.

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