Everyone is naturally afraid of M (Manual Mode). Why? Because it is intimidating as all get out to have to “do the math” that your camera’s computer normally does for you. But, I have found that finally breaking the threshold and shooting manual can be quite exciting and a great way to learn about nailing proper exposures.
There is somewhat of a dance that goes on between “the trinity” of exposure. ISO + F Stop + Shutter Speed. These three variables interact making the camera produce an image. Helping know this quasi-technical information has helped me to FINALLY grasp why my images were sometimes blurry when I shot my 50mm prime handheld.
The handiest thing in the world is the light meter in your camera. It helps you know where your image is going to come out – is it too dark (under exposed) or is it too light (over exposed) or, is it like baby-bear’s bed – just right? 😉 When the balance between ISO, F Stop & Shutter Speed is reached, the meter reads 0. You know that your exposure is where it should be for a “properly” exposed image.
I was trying this out the other day shooting some indoor natural light candid shots with my 50mm prime lens. I had set my F Stop at 6.3 and my Shutter Speed at 1/30. The light meter was bang on for a proper exposure. Click, Click, Click! When I looked at the image, it was blurry. Huh. Why?? The meter was balanced. But the Shutter Speed was too slow to produce a sharp image (hand held with no VR). Aperture Priority mode also failed me, even though it bumped the shutter up to 1/60 – it still wasn’t enough to make the shot happen due to camera shake/photographer unsteadiness.
Behold! The handheld rule! This finally made sense for me when I started shooting in M and paying attention to my meter. The rule of thumb for handheld is that your shutter speed must be *AT LEAST* 1/focal length of your lens. Which on a 50mm would be at least 1/50. But, there is one other factor to figure in on DX bodies – a cropped sensor. On Nikon, you need to times your focal length by 1.5 to figure this out. 50mm becomes 75mm! So, you need a shutter speed of at least 1/80 to make the shot sharp. A 300mm on a DX body, is 450mm, so you’d need 1/500 to get a sharp exposure. Tripods & VR change all this, but for photographers shooting handheld shots in natural light, this rule is a must to follow. When I cranked my shutter speed up to 1/100 and altered my F Stop to give me a balanced exposure, viola! Sharp, properly exposed images were the result.
Normally, I shoot in A mode and let the camera do the math. But every once in a while, it’s nice to grab the bull by the horns and jump into M. Trust your meter and the handheld rule of thumb and you’ll be well on your way to being an exposure ninja. 😉
PS: if you want to visualize “the dance” check out this website and experiment with shutter speeds and F stops