This is the 3rd part of a series on taking better real estate pictures. The series is intended for those that really want to produce high quality photographs of their listings, as opposed to just grabbing a few shots and dumping them on the MLS.
In Part I, we talked a little about the basics and the focus of the series (pun intended). In Part II, we talked about a few options for get, ranging from under $1000 to REALLY expensive. You don’t actually need to spend a grand to get great shots, but it doesn’t hurt. Feel free to jump back and review.
Exposure is broken down into several factors. Each one affects the whole.
The first, and most basic is ISO (film speed/sensitivity). This is a measure of how sensitive the sensor or film is to light. The higher the number, the more sensitive it is… and the less light is needed to create an image. But, that also means that the image is likely to be grainier.
Back in the old days… when people shot film… it was pretty easy to figure out what speed film you were shooting. It was printed on the box when you bought it. Now, with digital cameras, it is built into the camera… and most cameras offer a variety of film speeds, ranging from 50 or 100 up to around 800 or 1600. Some will offer a little more, others might offer less. Generally, for what we are doing, the lower the speed, the better. Usually, lower film speeds yield images with less noise. Doubling the number represents one full step in exposure. Examples of traditional speeds are 50, 100, 200, 400, 800, 1600 and 3200.
Generally to control the film speed, you have to be shooting the camera in a mode that isn’t “easy”. It might be the P mode, or it could be S, A or M. Usually, the camera will be in an “Auto Sensitivity” mode.
If we are being real serious and shooting in a fully manual mode, shutter or aperture priority, it would be good to set the sensitivity to something like 100. It would be a pretty good way to learn the rest of the exposure variables.
The next one we need to learn about is Aperture. This might be the toughest for most people to “get”. Usually that is because the term is unfamiliar, rather than the concept being that rough. Simply put, aperture is the size of the hole that the light comes through to hit the sensor (film). The higher the number, the less light is coming through the lens. Multiplying the number by 1.4 represents one full step. On SLR cameras, full steps are generally 2.0, 2.8, 4.0, 5.6, 8, 11, 16, 22, 32, 45 and 64. Often there will be an “F” in front of the number, like F8 or f11.
But, there is a little more to aperture than just how much light is shining through. It is a concept called Depth of Field. As the aperture gets smaller (larger number), the other change that is taking place is that the field of focus is stretching. Objects closer and farther away from the point of focus are getting sharper. This may be great… or it may be distracting. Portrait photographers often use shallow depth of field, throwing the background out of focus, to keep the viewers eye on the subject. Landscape photographers often use the opposite effect.
The third leg in the exposure triangle (I know, I said 4 things affect exposure) is Shutter Speed. Simply put, this is how long the shutter stays open to allow light to hit the sensor (film). Usually the numbers are represented as a fraction like 1/60 or 1/500. Traditional full steps are 1/2000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1sec, 2sec, 4sec and 8sec.
There are a couple of things to keep in mind here as well. To start with, for general photography, hand-holding the camera only works down to about 1/60sec with a normal lens and 1/30 for a wide angle. A telephoto might need 1/125 or even 1/250 to be steady. If you are shooting close-ups, you need a tripod or faster shutter speed. If you are well-practiced, you might be able to hand-hold the camera at a little slower speed. Allowing a little motion in the shot isn’t always bad, you just need to understand the result.
The 4th leg on this stool is Flash Exposure. I will likely have an entire post devoted to flash… but the basic rules to remember are:
- Shutter Speed doesn’t have much affect on flash exposure. The flash happens faster than the shutter.
- The only ways on the camera to adjust the exposure from the flash are with ISO and Aperture.
- Many flashes allow power to be adjusted.
- The light from the flash falls off as it gets farther from the flash unit. Half as much light makes it to 28 feet as made it to 20 feet… that is why the background often looks dark in flash photos.
If you really want to learn about this in more depth, I HIGHLY recommend The Camera (Ansel Adams Photography, Book 1) (affiliate link) by Ansel Adams. He has a tremendous amount of detail on cameras and exposure basics. It is continued in The Negative (Ansel Adams Photography, Book 2) (affiliate link). The Camera deals primarily with lens angles and other things relating to the camera, as well as a lot of technical things relating specifically to film cameras… and especially large format cameras. The Negative is all about exposure, and is an EXCELLENT read. If you are just going to get one, get The Negative.
- ISO Control (nikonusa.com)
- A Basic Look at the Basics of Exposure (nikonusa.com)
- Photography 101- Shutter Speed (stoneandrose.com)
- Understanding ISO Sensitivity (nikonusa.com)
- Learning about Exposure – The Exposure Triangle (digital-photography-school.com)
- Are you smarter than your camera’s exposure system? (presqueisle.org)
- Taking Pictures at Dusk and at Night (nikonusa.com)
- The Lost Art of Real Estate Listing Photography (grayflannelsuit.net)