Here are some recent questions I've had about camera gear and my answers. I know what I'm trying to say, but if anything is unclear, please let me know so I can fix it! I want a better lens, what should I buy? There are so many different ways to answer this question. Most people start with a crop camera (something besides a Canon 5D or 1 series) with a kit lens. Pretty much any lens you buy will be an improvement over that!
50mm fixed focal length lens. Beginning photographers often overlook this lens. However, it is one of the sharpest lenses you can buy and it is a very good value. Both Canon and Nikon have an f1.8 version that is less than $100 (and really great versions at $300 for the f1.4). Whenever I suggest this lens, I get asked why anyone would want a lens that doesn't zoom. The simple answer is speed. A fast lens lets you take available light photographs in less light, or extends the reach and power of your flash.
The lens that comes with most kits is something like an 18-55 f3.5-5.6. What this means is that the f-stop (aperture) at 18mm is f3.5 and it slides to 5.6 at 55 mm. Lets compare that to the cream of the crop lenses that are available. The 17-55 2.8 IS lens that Canon makes is 2.8 the entire way. That means that at 17/18mm the 17-55 needs 67 percent of the amount of light to get the same shutter speed. At 55mm, the 17-55 needs only 25 percent of the amount of light. Now, let's compare even the amazing 17-55 2.8 IS to the $80 50 f1.8. The 50 f1.8 needs 33 percent of the light that the 17-55 2.8 needs to reach the same shutter speed. Compared to the kit lens at 50mm, it needs a mere 8 percent. You can get even more light if you go with the 50 1.4 which sits at 6 percent of the kit lens, which is a significant improvement over the 1.8.
However, having a fixed focal length lens does make it hard when you want to include more or less in the photograph (sometimes this is called the human zoom because the photographer has to move forward or back). Therefore, I also recommend the 17-55 2.8 IS lens for Canon users. Nikon also makes a version, but without the internal image stabilization. These are exceptionally high quality lenses that are capable of creating amazing images in the normal (for a crop camera) zoom range. If you can't afford the Canon/Nikon version or if this is just one of many hobbies, I have heard good things about the Tamron 17-50 2.8. When you switch from one the kit lenses to one of these, you will suddenly start seeing an increase in good photographs. Those using a full-frame sensor (5D & Canon 1 series), I suggest the 24-70L.
In addition to the light gathering advantages that these lenses offer, they also produce more "out-of-focus" areas. This is a huge advantage. Many photographers, like myself, love this. It enables the photographer to isolate the subject from their surroundings.
This photograph of my daughter's friend was taken with a wide aperture to make her stand out from the background
A lot of people also want to be able to take photographs of their kids sporting events. Depending upon the type of sport, you will need different equipment. For inside sports such as basketball and gymnastics, I would recommend the 50mm 1.8 (or 1.4 for a better built lens) or the 85 1.8 (or 1.2 if you have an extra $2000 to invest in your hobby). For outdoor sports, it's hard to beat the 70-200 zooms. The Canon 70-200 2.8 L IS (VR for Nikon) lens is fantastic. If you don't want to spend that much, I suggest the 70-200 4.0 L or the 70-200 2.8 HSM Sigma.
The last type of lens that someone would need would be a wide-angle. These are great for landscapes, architecture, group portraits, and for creating interesting images. I personally love wide angle lenses, but I didn't so much when I was first starting. The lenses I would suggest in this category would be the Canon 10-22, Nikon 12-24 and Tokina 12-24. For those that have a full-frame sensor, I suggest the 16-35L.
Are there situations where I wouldn't want the 2.8? I was taking pictures with it on auto and sometimes it would set to 4.0 - Should I set it to 2.8? What does 2.8 really mean?
Okay, there are several related questions here, so I will start with the most basic and work my way through them.
In the simplest terms, the aperture (f-stop) number represents the amount of light that the lens allows through to the camera. Each f-stop difference means the light allowed through is half of the f-stop before it. In the olden days when I started in photography, the numbers of the f-stop were engraved on the lens, so it was easy to remember them. The full f-stops are 1.0, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11, 16, 22, 32, 45, etc.
This image was taken with a smaller aperture to make everything from the wood post to the Herb Farm in the background in focus
The obvious question at this point would be, "So what does that do for me?" What it means is that the lower the aperture number, the more light a lens can gather, which allows for higher shutter speeds, less camera shake causing blurry images, less need for flash, and when you do use flash you have greater range and options with your flash
Something else that changes with the aperture is the Depth of Field, or how much of the frame is in focus. If you are taking an Ansel Adams type landscape, you will want to shoot at something like f22. If you want to isolate your subject from the background, you will want a very fast aperture (like 2.8 or faster) to throw everything else out of focus.
This is another example of a shallow depth of field.Â Her eyes and mouth are in focus, but the tip of her nose and her ears are out of focus, ensuring that when we look at the photograh, we look at her face and aren't distracted by the background.
Next time I'll tackle the question most often asked of me at weddings, "Why is your flash pointed sideways?"