Av and Tv modes explained…
hmmm, ok so while on the P setting on we find that it gives us that little bit more control of our photo’s.. maybe not for you but it does for me, that is, compared to full auto.
Moving on to Av – Tv modes. ooooh we almost at that feared M setting.
First up Av mode but before I do that I wanna tell you something about what I’ve learned so far.
Most of the camera’s settings is just different ways to control the way light enters the camera – the photo’s we take are made up of light bouncing off objects.
Ok now we can start.. Av mode or aperture priority basically controls depth of field(DOF) of the photo. What is the DOF?
Example:
This is shot with a shallow DOF. Depth of field is controlled by the F number. On your camera probably looks like this.. 1/60 F5.6.
The 1/60 being shutter and F5.6 being the aperture. The smaller the number next to the letter F the shallower your DOF and visa versa.
Note that in Av mode you can choose different f stops by using the wheel on your camera and the shutter speed will be automatically calculated by the camera. So its safe to say we are still in semi auto mode.
Settings for the shallow DOF picture is 1/4000 F1.8 and ISO 100.
The photo on the right is shot using a greater DOF. And immediately you can see the difference right ? The sunflower in the background has more details than the one with shallow DOF. Smaller DOF is great for portrait photography and big DOF is great for landscapes. It all depends on your style of shooting.
Note when using a greater F number your shutter speed will decrease, so depending on the amount of light in the scene you might want to support the camera on a rock/tripod/table whatever you can find.
Settings for the greater DOF shot is 1/160 F 13 and ISO 100. See the drastic change in shutter speed compared to shallow DOF.
The aperture is lens dependent, meaning that different lenses have different apertures.
With the kit lens the minimum aperture is 3.5 at 18mm and 5.6 and 55mm.
Also remember that the smaller the aperture the more light your lens allows in. So smaller aperture lenses make for great indoor photography.
The EF 50mm II F1.8 lens is a great lens as well as affordable. So go into your local camera shop and ask them for it.
Happy Snapping .. Until next time 
to be continued….
