You've had point and shoot cameras for maybe two or three years. You've read hours regarding the technical aspects of taking a picture, such as Exposure, Aperture, White Balance, ISO, etc. Your pictures have improved a lot, and you have started to pay more attention to the artistic aspects of taking a picture; capturing a precise moment in time, making stronger compositions, the importance of lighting for setting mood...and suddenly you realize you deserve an upgrade to a digital SLR.
I know about it, because I had to go through the same path. Having shot for something like three years with Canon point and shoot cameras (Powershot A70, Canon S2IS), I felt like it was time to go more serious. Using a point and shoot to learn the basics is nice, because you begin with a self contained photographic system. No need for one lens for wide angle, one lens for casual photography, one for tele, etc, etc. You just take pictures and that's it. No non-sense. Totally portable.
On the other hand, when pushed too far, you start to realize the limitations of such cameras: not very big maximum apertures (making difficult to take pictures in low light and almost impossible to get shallow depth of field at small focal lengths) low ISO settings (which means it's difficult to take sharp pictures with low light), they are pretty slow to react (hence making very difficult to take pictures of action in the right moment), etc. You won't notice these shortcomings at first, but after a while they become a limiting factor in your creative possibilities and this is when you need to go to the next level.
Buying a SLR may at first seem daunting, but with a few concepts and links to visit, you should be set.
What body to get
After a lot of researching, it was clear to me that going for a higher end body wasn't necessary. Currently available entry level bodies offer lots of features, are lightweight and won't cost and arm and a leg. Bodies are updated every couple of years, so why bother wasting extra money
on a piece of equipment that will get obsolete in no-time anyway?
Since all my imaging equipment is Canon (HV20, S2IS, Powershot A70) it was a no-brainer for me, I went Canon again. I know how they work, how they call different functions, etc. This way I maximize my technical knowledge and don't have to learn another nomenclature, menu system, etc. The less I have to *think* to take a picture, the better. Tools should stay out of the way of your creative flow.
As of the beginning of 2008, the entry level model for Canon Digital SLRs is Canon EOS400d (also called Rebel XTi). In this same league Nikon offers the 40d, Sony the A100 and Pentax the K100D. Any of them should be more than enough to begin with. Pick your choice, and start taking pictures.
What lenses to get
This is where the fun begins. A well thought set of lenses should last for the years to come, even if you upgrade the body. So, this is where the real investment will be. What lenses you buy will depend on your photographic interests.
Focal length and aperture
The first thing you will notice when doing the transition from point and shoots to SLRs is that no one ever talks of the amount of magnification of the lenses such as "10x", "12x", etc. You should think in terms of "focal length" instead. It doesn't make much sense to calculate the "x" of your system, so better forget about it. On a 35mm film camera, 50mm focal length is generally considered to be equivalent of what you see with the naked eyed. Anything shorter is considered wide angle, anything longer tele.
Lenses are identified by focal length and aperture. Let's see some examples.
- 28mm f/1.8
28mm: This is a fixed focal length lens, at 28mm.
f/1.8: This lens features a fixed maximum aperture of 1.8. Very good for low light conditions. Moderate wide angle.
- 55-250mm f/4-5.6
55-250mm: This is a zoom lens (meaning it has variable focal length). The shortest focal length being 55mm, the longest 250mm.
f/4-5.6: When the lens is at 55mm, the maximum aperture for this lens is 4.0. When at 250mm 5.6. Overall, quite a slow lens, not very good for low light conditions. Moderate tele.
One small caveat. Most digital SLRs (and certainly entry level ones) feature an image sensor that is smaller than a 35mm film strip, so the image generated by the optics is cropped (imagine that you physically cut the 35mm film with a scissor, so that you end up with a smaller piece of film, hence with a smaller part of the original image). How much this cropping is depends on the crop factor. On Canon's EOS 400d the crop factor is 1.6.
Focal lengths are always expressed related to 35mm film. So, In order to calculate the effective focal length for your camera, the formula is:
focal length * crop factor
So the 28mm lens in the example above used in a Canon EOS 400d becomes a 44.8 mm one. Don't forget about it.
EF, EF-S, USM, IS, L and other technical jargon (Canon cameras)
- EF stands for the connection featured on modern Canon lenses and cameras. This lens will work on all modern Canon SLR cameras.
- EF-S means a lens specifically designed for APS-C 1.6x crop factor cameras.
- USM means Ultra Sonic Motor. It means the lens focuses faster and with less audible noise.
- IS means image stabilization. Lenses with image stabilization allow you to take hand held pictures with longer exposure times without blur. Depending on the lens, you could expect gaining between 2 and 4 f-stops with IS.
- L means this is a luxury lens. Top-of-the-line. Expensive. Optically as good as it gets.
So, let's suppose I wanted to get a EOS 400d system that is equivalent to my Canon S2IS. According to the specs, the S2 IS features a 36-432mm f/2.7-3.5 zoom equivalent to 35mm film cameras.
There are several ways to make such a system with a digital SLR. An example:
- 18-55mm f/3.5-5.6 standard zoom (with the crop factor it becomes a 28.8-88mm)
- 70-300mm f/4-5.6 telephoto zoom (with the crop factor it becomes a 112-480)
- 17-85mm f/4-5.6 standard zoom (with the crop factor it becomes a 27.2-132mm)
- 70-300mm f/4-5.6 telephoto zoom (with the crop factor it becomes a 112-480)
This combination gets us closer to what we want. The two lenses overlap a bit, but that's Ok.
So far so good, theoretically. But ask yourself, would you want to haul around a bag full of heavy, expensive lenses just to cover all possible focal lengths? Or would you rather have a more portable system? Many folks opt for just one bread and butter lens for general walk around, such as a 17-85mm, which gives moderate wide angle and tele, and leave the more specialized ones at home.
Notice that both combination of lenses gives quite a slow system (the maximum aperture is f/4, not very fast), so it wouldn't be of much use for low light conditions. What most folks would do is just add a fast lens, such as a 28mm f/1.8. Another detail is that none of the mentioned lenses features a powerful wide angle, so that may be another point to take into account if you are into architecture or landscape photography.
As you can see, there are infinite options, but don't worry too much yet. Let yourself get accustomed to the new system, learn its possibilities and limitations and after that, pick the lenses that best serve your style.
+Info
Canon Lenses Reviews
Building a digital SLR system
Poll: Starter lens for Canon DSLR under $400 US
Canon lens recomendations
Why Is My 50mm Lens Equivalent to 80mm on a 35mm Camera and Why Is There More Depth-of-Field?
