|MadSci Network: Engineering|
Hello, Sarah, Danielle, Wendy, Neil, and Katie - thanks for your question. Yes, cameras make a big difference to the quality of your image. There are several aspects to consider though, and a lot of the decision in choosing a camera will depend on what you want from your images. First there is the lens – to make a camera all you need is a pinhole – the smaller it is, the sharper the image – but the longer the exposure takes. So lenses get round that. They come with much bigger holes (called apertures) to let the light through than a pinhole and rely on the shaping of the glass (or plastic) to make sure the image is sharp all over. Some lenses are better than others and produce sharper images than others. Equally, some lenses come with bigger apertures – which allows the photographer to take pictures in lower light conditions at the same shutter speed. The best lenses can have large apertures and are capable of giving give sharp images all across the scene. They are expensive. As with everything else, you get what you pay for. Secondly there is the format that the camera uses. If you want to make a print, the less magnification you have to use, the better the image will be. Back at the beginning of the century (it’s not actually over yet..) cameras could have huge plates giving negatives as big as the final print. The quality was superb. But the camera was big, not very handy to use and so on. So smaller and smaller formats have been developed and advances in films have allowed this with decent final image quality. Nevertheless format size is important. There is another point, though – smaller format allows the scene to be focused down on a smaller area – so all the light collected is more concentrated – this means cheaper lenses for a given effective aperture. In turn this means cheaper cameras for similar abilities to take pictures in given light conditions. So it’s all about compromise. If you want to make great big enlargements – you want the biggest format you can get away with, and generally 35mm is as small as you would go. Digital cameras usually have very small formats – so magnifications can be huge and it doesn’t really matter how many megapixels the camera boasts, the lens probably can’t resolve to a frequency better than the equivalent of a couple of megapixels on such a small imaging sensor. This magnification factor is why digital cameras still have a long way to go to catch up on conventional ones – if you want really good enlargements. Thirdly there are other factors to do with the range of shutter speeds (how short a time the lens is open), how vibration-free the shutter mechanism is and so on which distinguish good cameras from not-so-good. The proof of the pudding, as they say, is in the eating. It’s the final print – or slide – or digital image - that matters. If it’s good enough for your purposes – then – no need to spend more money. The choice is huge, and you can get terrific pictures even from a one-time-use camera – which is pretty cheap. You can also spend literally thousands of dollars on cameras and lenses which will give great quality and allow picture- taking in a much wider range of conditions. I hope this is useful and not too complicated. If you have any more questions or don’t understand anything e-mail me (firstname.lastname@example.org) – I will not be able to answer (vacation) for the next week but promise to do so after then.
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