What is Magnesium Alloy?
To begin with, magnesium alloy is a metal that consists of magnesium and another alloy metal such as aluminum. It is a popular metal used in electronics such as laptops, camcorders, and cameras! But since this is a photography page and not a science/engineering page, let's move on, shall we?
Why is a Magnesium Alloy camera body any better than plastic?
Prosumer (and some mid-range) DSLRs are constructed out of magnesium alloy, a metal that is not only durable, but also lightweight. Entry-level DSLRs such as the Canon EOS Rebel series, or the Nikon D3200 are generally constructed with polycarbonate, a strong plastic that is even used in bullet-resistant glass. You might be wondering, “So what’s so great about magnesium alloy when polycarbonate does the trick?” Well…
Magnesium alloy has several amazing properties that make it great for professional photography. First of all, it is corrosion-resistant, which is a desired property when having to photograph in the rain or near water. Many journalists need a camera that simply works, no matter the condition, and that's why many of them go with a camera in the Canon 1D or Nikon D4 series. Of course, this is not an essential property if you don't seek to go out and take risks with your camera, so we'll carry on.
Another great quality that magnesium alloy provides is high temperature endurance. This can be helpful as extreme temperatures are surely encountered with photography, whether it is INSIDE or OUTSIDE the camera. Imagine going out to shoot near a volcano with a polycarbonate-body DSLR. You have scorching hot temperatures engulfing you that are nearly burning your clothes off, and then your DSLR starts to melt in your hands! (Okay, this is probably not very likely…) But still, you will want to have a camera in hand that can handle extreme temperatures, whether you are shooting in the desert or in the frozen tundra, as it will ensure that you have a fighting chance to come out with clean photos.
Although you may think a magnesium alloy body would be heavy, it is actually half the weight of what an aluminum body would weigh. Also, because it is a metal, no matter how much you drop your camera body (totally not recommended by the way), you still have a high chance of it not cracking, compared to any plastic out there.
Lastly, it just down right feels PROFESSIONAL! The heavier weight that it provides gives the camera body a solid and sturdy feel. With this, you can have reassured confidence that the expensive beast of modern technology in your hands will DEFINITELY hold up for most of the tasks you need it for.
Now realize that we often use the term, resistant, and there’s a reason for that. No matter how much engineering evolves, we can never have an absolute guarantee that things will not malfunction or act different from advertised. Leave a camera in the mud, it will break down, leave a seed in the same mud, and it will grow. Nature is just hard to beat, but with great technology such as the development in magnesium alloy, at least we have a better chance against it.
Now what would be interesting to see would be a carbon fiber body. Hmm…