Photographs
Point and Shoot Cameras
I thought of another consideration for depth of field context. This is when using a smaller point and shoot camera. These cameras have put photography in the hands of almost everyone who walks in public. You cannot go out without seeing a tourist pointing a camera. Thus I wanted to address how depth of field occurs in these cameras. As you probably know, the lens on them is very small. If you are not familar with focal lengths, basically it is defined as the distance from the focal plane(where the pictures actually gets recorded – film if you will) to the end of the lens. It is usually calculated in millimeters for standardization. For reference, a macro or wide lens in photographer terms usually is anything 35mm or less. The next is called a normal lens and is 50mm for a standard SLR camera. Another term used is telephoto lens which usually means greater than 80mm. A note, these numbers are for SLR cameras only. Calculating the focal length totally depends on what format of camera being used. A large format camera has a normal lens which is different than 50mm. If you wish to know how to calculate it, read this Wiki Article. Also you might wonder what f-stop means when referring to aperture. Well the formula that yields the f number is focal length divided by diameter. Ok back to lenses. The average point and shoot usually has a small zoom lens which varies from 12mm to 35mm give or take a few. In other words, a wide lens. So as you learned in the discussion about depth of field, wide lenses, other factors ignored, yield a high depth of field (totally clear background). So when shooting photos with a point and shoot, most of the situations will make it difficult to get a shallow depth of field if that is what you are after.? Another note about point and shoots is that the f-stop generally cannot go smaller than f6 and often not even that small. I have found even if the camera is set to its automatic portrait mode, you still see a clear background, as in the above example. My face, sunglasses, eyes, nose, and other attributes along with everything outside the train window are clearly identifiable.? If for example I wanted the window and outside to be blurry, I would have needed a smaller aperture and/or a longer lens which is unavailable on point and shoot cameras.? The programmed f-stop for these cameras is usually between f2 to f6 if that depending on the zoom level.? So because of both of these factors, it is nearly impossible to get a shallow depth of field unless your subject has his nose pressed to the camera lens :)? I hope this information has been helpful for novice photographers.
Flash Photographs
I wanted to do a follow up posting to the one about Depth of Field.? I forgot to mention that as I learned when I started taking indoor photos with flash, depth of field can be affected by using a flash too.? Let me post a few example photos so you can see what I mean.? In the two examples above, the differences are subtle.? For example, the drag queen clawing at you, the only blurry area is the lower part of her dress.? That is closest to the lens.? Everything in this background is clear.? Also in the photo with male acrobats notice the man’s face on lower portion is blurry while the other face and the equipment on the left are clear.? The clapping hands are blurred too.? This result for f4 should have given slightly less depth of field.? My intent was actually to just get the stilted guy on top in focus and have the rest blurred.? To do that, I would have needed f2 or f1 and would have needed a longer lens and to distance myself from the subject.? The other challenge was the fog machine.? In clubs with a fog machine that makes a fake smokey environment, the flash often can bounce.? And thus you get less light in the exposure.? I guess I could go on and on about flash photography variables since this has become my specialty now but just ask in comments if you are curious about a certain scenario.