If you’re taking JPG images in a high-quality compression, how many will you be able to squeeze onto your memory card? That’s a question often asked.

Here’s rough guide to what you can expect from a variety of memory card capacities:

1 MP (megapixel)
32MB card: 91
64MB: 182
128MB: 356
256MB: 731
512MB: 1420

3 MP
32MB: 26
64MB: 53
128MB: 106
256MB: 213
512MB: 421

5 MP
32MB: 12
64MB: 25
128MB: 51
256MB: 102
512MB: 204

These numbers may vary according to how your camera processes images, so use as a general guide only.

What sort of batteries are best for your digital camera?

I ask this because I recently had a battle to get an online camera store to send me the rechargeable batteries advertised in the national press, instead of the 2 x AAs they actually sent me. It took them six weeks to admit the error and I’m still awaiting the goods, though DHL assure me they are on the way.

So, was it worth the effort? The package promised of NiMH rechargeables, plus a battery charger will save a fair amount of money in the short, medium and long terms.

On average you can use rechargeables over 100 times. If you change your AA batteries every month, the cost of alkalines will far exceed your occasional purchase of the use-again type. It will also save on shoe leather traipsing back and forth to the camera shop. The more you use the camera, the more you save.

A camera with a proprietary lithium brick battery also sounds good, but if it runs out in the middle of a shoot, you’re done.

Being able to stick in a couple of spare AAs will keep you shooting whatever happens. So bear in mind all these points when it comes to choosing your camera. Battery type could be an important consideration.

The Sony Cybershot DSC-W100 has been well reviewed over at Imaging Resource: ‘The Sony DSC-W100 is an impressive offering, much like the rest of the W-series in the Cyber-shot line. It is handsomely constructed, with a feel of quality, and is uncomplicated to operate. With its high-resolution 8.1-megapixel CCD, large LCD monitor, and very accommodating exposure offerings, the DSC-W100 is definitely a winner in several categories.’

Check out the latest price of the Sony DSC-W100 at Amazon.

As well as a 5-star review at Amazon, the Canon EOS 30D digital camera has been very favorably reviewed at Trusted Reviews: ‘The EOS 30D is the replacement for the extremely popular EOS 20D, which was launched in August 2004. … Canon’s 8.2MP CMOS sensor produces more detail, greater dynamic range and less image noise than any comparable CCD sensor, and the DIGIC II processor deserves every accolade it has won. Shooting in a range of weather conditions from dull and overcast to bright sunshine, I found that even shooting only in program mode with default colour settings the camera turned in nothing but superb shots time after time.’

Check out the latest price for the 5-star Canon EOS 30D at Amazon.