Digital SLR: FAQs
How much do extra lenses cost?
Lenses can be expensive. They start at about £80 or £90 and can go up to the thousands. The more expensive lenses tend to be fixed (non-zoom) lenses that have long focal lengths (for example, 300mm, 400mm, 500mm etc).
Lenses with large maximum apertures (for example f1.8 and below) are also usually, but not always, expensive. The ones that aren’t are usually great value. Large maximum aperture lenses have advantages – see our section on lenses for more information.
If you choose a lens with image stabilisation built-in, such as some in the Canon and Nikon ranges for example, again you can expect to shell out.
We test all our DSLRs with the standard kit lens they are often sold with. This kit lens is usually fairly low quality. Fitting high quality lenses can really open up the potential of your DSLR.
What's the benefit of those big flashes that I see some professionals use on their cameras?
Nearly all cameras have a built-in flash, but there are times when its power isn’t enough, perhaps if your subject is a bit further away – this is where external flashes come in.
Most give you more control too, you can swivel the head so the flash light doesn’t point directly at your subject for example. Pointing your flash slightly away from your subject can make for a more natural looking picture.
How big a problem is dust?
Most DLSRs now have anti-dust technology which to some extent has minimised the problem of dust entering the camera, falling and remaining on the sensor and manifesting itself on your photos.
However, the more lens changes you make, the more chance dust will enter the camera and stick on the sensor. Also, changing lenses in dusty conditions or leaving the camera 'open' with no lens on it increases the chance of dust.
As a worst case scenario, dust can manifest itself as large dots on your photo, or if you’re luckier, small, almost invisible dots.
Dealing with dust
You can remove these dots when they affect your photo using photo editing software. Or, you can try to clean the sensor yourself, perhaps using a product designed for the purpose – check the manufacturer’s instructions for more advice.
Cleaning the sensor yourself can be risky though as sensors are delicate. Another option is to get the sensor professionally cleaned – this usually costs though.
Minimising the risks
To minimise the risk of dust, try not to allow the sensor to be exposed for too long. In other words, change lenses as quickly as possible with the camera switched off.
Also, keep the camera facing down as you do it – keeping it round your neck using the strap is a good idea.
But don't worry too much, as anti-dust technology seen on current DSLRs has minimised the problem.
What is RAW?
This is a type of file format that DSLRs and some high end standard cameras can create. It gives maximum image quality and versatility when editing with photo editing software, but file sizes are very large and they require some processing in photo editing software before they can be used.
To give an idea of the size of RAW files, a highest quality JPEG image taken with a Canon EOS 40D will be approximately 3.5MB, whereas a RAW image will be about 12.4MB.