A longer range telephoto is always a handy addition to your kitbag, for example a cheap 55-200mm lens or 70-200/70-300 (like
THIS or
THIS. You could also get other brand lenses like Sigma or Tamron that are cheaper at the cost of a tiny loss of quality [like
THIS or
THIS in a Canon fit]). This will allow you to shoot most wildlife or sports, or just for general times when you need that little extra bit of reach. It's also worth getting the very cheap
50mm F/1.8 lens. This kind of lens is perfect for portraits and places where you need a VERY shallow depth of field (explained later).
The person who told you the 18-55 kit lens is bad for AV (or Aperture Priority mode) is wrong, but the lens could be better. Your lens always comes with an "F-number" after the lens length, which can range from F/1.2 to F/6.3, or a range of these numbers (e.g. F/2-4) I think your lens is F/3.5-5.6.
This number is the aperture of your lens, and it performs 3 functions:
It allows light to pass through your camera onto your sensor
Basically, an aperture is a hole in your lens
(now for the important parts)
It is variable and can regulate the shutter speed
What this means is that depending on camera settings, the hole can get larger or smaller, regulating the amount of light getting let in. A larger aperture (or SMALLER f-number) lets more light in, whereas a smaller aperture (or a LARGER f-number) lets less light in. This means that a larger aperture needs a faster shutter speed to create a "proper" exposure and vice versa for smaller apertures.
It also regulates the Depth Of Field (DOF)
The depth of field is how much of your photograph is in focus, and how much a subject "pops out" in a photo. A larger aperture (smaller f-no.) gives a more shallow depth of field suitable for portraits, whereas a smaller aperture (remember?
) gives a larger depth of field suitable for landscape photos etc.
As with most things in photography, aperture settings are a compromise. If you're shooting sports, you'll need to sacrifice depth of field in order to get a faster shutter speed, and if you're shooting something where you want everything to be in focus, you'll need to sacrifice shutter speed. Also, while we're on the subject of compromises, a lens doesn't perform at its best at very large or small apertures (e.g. F/5.6 or F/22); it performs best (and the photos are sharpest) in mid-range apertures like F/7-F/16. However, this shouldn't worry you too much, as it only makes a small difference on your kit (no offence
)
Now, as to why that guy said your lens is bad for aperture priority. Your lens has a rather small maximum aperture compared to some of the professional lenses (
like this one [Yeah, yeah, it's 17-55, whatever :greenpbl:]). At 55mm, your lens has a maximum aperture of F/5.6, whereas a pro 18-55 lens would have a maximum aperture of F/2.8. This, of course, means that the pro lens would be able to make a subject "stand out" more than your 18-55 could. However, your 18-55 can still give a rather shallow DOF, so you really shouldn't worry; your 18-55 is just fine for aperture priority mode.
Well, I think that's apertures covered. If you've got any more questions, I'll try to reply as soon as possible (or another person might). Bye!
~TamiyaGuy
