Setting Custom White Balance on Your DSLR. A follow-up to my Color Temperature & White Balance video. Check out the other videos on my YouTube channel and subscribe to the channel for updates.
Full-Frame DSLRs and Depth of Field
August 22, 2011 By 9 Comments
Kenneth wrote in with a question about the sensor size of the cameras I used to produce the example images in my eBook, Taking Your Portraiture to the Next Level. He wanted to know whether I was shooting with a full-frame sensor or a smaller (e.g. APS-C) sensor. I’ve received this question from other people, but instead of just answering (it’s usually APS-C), this time I thought I’d ask why the answer to that question seemed relevant.
It turns out Kenneth had very good reasons for wanting to know.
“I shoot with an APS-C DSLR,” says Kenneth. “If one of your photos indicates you used a 50mm lens and you had been using a body with a full-frame sensor, then I would know that to duplicate your setup, including camera position, I would need to use my 35mm lens. Also, if you had been using a body with a full-frame sensor, I would know that I would have to use an F-stop about one stop wider to get the same DOF result from the same camera position.”
It took me a moment to wrap my head around such a technical concern. But as it turns out, there are many of you out there who are interested in DOF estimations/calculations. Under certain circumstances, getting a handle on DOF and having refined control over it might be very important indeed. I personally don’t worry about it too much in my portraiture, because I simply adjust to taste as I go along. I have a general idea of what I want, and know, generally, how to achieve it. If the DOF preview doesn’t suffice, I’ll take a test shot or two to make sure things look right to me. But, everyone doesn’t work that way, and if you’re trying to learn by reproducing what you’ve seen in another photograph, nailing down (and making adjustments for) all the settings, positions, lighting, and gear used in the original can be helpful. In any event, here was my response, as I thought this might make a good topic for this post:
Let’s start with the idea of a 35mm lens vs. a 50mm lens:
1) Since images are routinely cropped to improve composition, editorial or album layouts, or for any number of reasons, there is no point in trying to duplicate the “framing,” of an image via the focal length of the lens. What appears to be a tight, close-up position, might actually be a cropped version of a wider shot.
2) I would hesitate to use a 35mm or wider lens for many of my shots. Especially as you get closer to the subject. The perspective distortion might be slight, but might still be noticeable.
Now, about DOF:
1) With the same lens (same focal length), using the same aperture, at the same distance, I do not see why the DOF would be any different based on the sensor size. The field of view would be cropped, but the DOF theoretically should not be affected. Although Kenneth isn’t suggesting this is the case, there is a common misconception that sensor size alone in some way has an effect on DOF (all other conditions being the same).
2) Given the conditions above, if camera distance were altered in order to make a field-of-view adjustment (move the full-frame camera in closer to the subject to achieve the same in-camera framing as the smaller sensor camera from the original distance), then of course DOF would be affected, because of the difference in distance.
The initial question is valid in situations where the following is the case:
- Smaller (e.g. APS-C) sensor on one camera. Full-frame on the other.
- Equal camera-to-subject distance.
- Same “framing,” or field-of-view (FOV). The subject fills the frame the same way in both cameras, on both sensors.
- Same DOF for both images.
The focal length of the lenses would have to be different in order to achieve the same in-camera field-of-view. And, since the focal lengths are different, but the distance is constant, it’s very likely the DOF will be different without an aperture (F-stop) adjustment.
Check out DOF Master and their excellent explanation of this topic >>
Photography Class: Lenses
April 27, 2011 By 3 Comments
The Photography Class series covers the basics of photography. This series is intended primarily for beginners and students. This is the second post in the series.
Different types of cameras make use of lenses designed for their specific lens mounts and formats. Here, we’ll limit our discussion to the lenses most often used with DSLR cameras. DSLRs give you the opportunity to use a variety of lenses to suit your needs. Here are a few basics on what’s available and what you should be familiar with:
Focus: Most of the lenses currently available for DSLRs work with the camera system to provide automatic focus. Sophisticated camera/lens combinations can automatically select the best area of an image to focus on, based on programmed algorithms and even face detection. Predictive focus is available for moving subjects and digital or mechanical stabilization mechanisms help prevent or minimize blur caused by camera movement. More controlled, single-point autofocus, as well as manual focus is also standard.
Kit Lenses: Cameras can be purchased without a lens, or with high-end lenses but most entry-level shooters buy the standard package camera/lens combo. The standard consumer-level lens that comes in these packages is called a “kit” lens. These tend to be lower-priced zooms that serve as all-around lenses. Optical quality is usually OK with these but they are usually slower lenses, meaning their widest aperture is about f/3.5 – f/5.6 depending on the state of the zoom. There’s nothing wrong with using a kit lens but at some point you might want to upgrade to something with a wider maximum aperture that does not change when you zoom, possibly more durable, and providing better optics and focus features and mechanisms.
Fixed or Prime Lenses: If you’re used to being able to go from wide to telephoto with your lens, then you are using a zoom lens. A fixed or prime lens is like having your zoom stuck to one focal length where you can still focus, but you can’t go from wide to tele. It might sound like a big limitation, but these fixed focal length lenses are very popular because they can have optics that far exceed the quality you’ll get from zoom lenses. Plus, very wide apertures are available with a fixed focal length (f/1.2 is an aperture that would allow faster shutter speeds and lower ISO settings than you’d get from a zoom). My favorite prime lenses are my 50mm f/1.8 and 85mm f/1.8. When using a fixed lens, you’ll need to move farther from your subject to get a wider view, and closer in to get a tighter view. Some call this, “zooming with your feet.”
Zoom Lenses: Zooms are lenses that allow you to smoothly move from very one focal length to another (e.g. wide to normal, wide to telephoto, etc.) from a stationary position. Like fixed/prime lenses, these come in a variety of focal length ranges. Favorites include the 17-40mm, 16-35mm, 24-70mm, and the 70-200mm range. There are some that cover a wider zoom range in a single lens, but they are not always of the best quality optics. Zooms can be very useful depending on the types of images you want to shoot, and in cases where you might need to switch quickly from wide to normal, or normal to telephoto, shots.
Wide Angle Lenses: These will allow you to capture more of the scene in front of your camera than you can with a normal or telephoto lens from the same vantage point. These lenses are good for many situations, but not generally for up-close portraiture, because the wide angle tends to distort the subject (things nearer to the lens, like a nose or chin will look unusually large). Wide angle lenses are in the 16-35mm range, give or take. Ultra-wide and fisheye lenses (around 8mm) provide extreme wide angle coverage, but they also necessarily distort the view of the scene.
Normal Lenses: One way to think of a so-called “normal” lens is that it approximates a field of view that the human eye sees. Many people think of 50mm as being the standard normal, but anything from 35mm to 70mm might be considered normal on a given DSLR. Lenses in this focal length are good for general photography where you want to avoid distortion but have a relatively good field of view. Suitable for portraiture and general subjects.
Telephoto Lenses: From about 70mm on up, you’re in the telephoto range. These lenses can be great for sports, wildlife/nature, and other situations where you want to get a tighter shot but can’t physically get close to your subject. Telephotos also make great portrait lense as they can provide you with a pleasing blur of the background as the visual distance from subject to the background is pronounced, especially when using wider apertures.
Macro Lenses: When you want to get in really close on tiny subjects or details, you’ll want to use a macro lens (or some type of adapter that gives you similar results). These lenses will often be capable of projecting a 1:1, actual size, image of the subject onto the recording media plane. In other words, you’ll be able to take pictures with great detail of tiny objects. Macro photography opens up another world to the photographer and viewer. The details on insects, plants, and small objects are magnified and easily captured with these lenses.
What to look for in a lens: All lenses are not created equal. Build quality, optics, weather-proofing, focus mechanisms, stabilization, and aperture are all important considerations when choosing a lens. Popular wisdom states that lenses made by the manufacturer of the camera tend to be better than those made by third parties. But, even within the manufacturers’ vast selections, lenses are often grouped into consumer-, mid-level, and professional-quality lines.
Most of us would like the best gear, but it’s always a good idea to consider the best solutions we can afford, for the types of images we want to produce. Also, keep in mind that price and quality designations aren’t always good things to base purchasing decisions on. Many photographers prefer certain “cheap” lenses over their more expensive alternatives. That’s not always the case, but it is sometimes. Do plenty of research and ask around when considering a particular lens. You might find you can get great quality for a lot less money.
Lens Filters: When you buy a lens, the salesman will almost always suggest a lens filter as an add-on, to protect your investment, of course. These glass filters are supposed to keep you from damaging your lens from scratches or some type of breakage should something hit the front element just right. I would use them if two things were in play: 1) I was working in a particularly hostile environment. 2) I had a history of smashing my front lens element into things or sliding it across nasty surfaces. Otherwise, if I’m really worried about damaging the already durable front lens element, I leave the lens hood on to help deflect other objects from coming into contact with it.
Why invest so much in quality glass just to cover it up with another layer of glass that is not likely to improve the optics? I’ve shot in some rough conditions, treated my lenses badly, yet never messed up the glass. I don’t use lens filters. However, if it makes you feel better, give them a try.
Crop Factor: Often mistakenly called a “magnification factor,” or a “focal lenth multiplyer,” a DSLR’s crop factor relates to how the size of its sensor, as compared to a full-frame sensor or the size of the image captured by 35mm film in an SLR, crops some of the field of view provided by the lens.
Most DSLRs have sensors that don’t capture as much of the image being projected through the lens as larger sensors can. These smaller sensors essentially “crop” out a portion of the projected image. People like to compare the crop to focal lengths (e.g. a lens designed as a 50mm lens for full-frame DSLRs or film SLRs essentially gives you a field of view similar to a lens in the 80mm range when used on a DSLR with a smaller sensor). You can find charts on the web that can specify the crop factor for your camera, and how it applies to different standard focal length lenses. I don’t really concern myself with these details because in the end you’re still going to use a 70-200mm or an 85mm for certain subjects and situations, and you’ll just compose and shoot according to what you see in the viewfinder.
Photography Class: Cameras
April 19, 2011 By Leave a Comment
The Photography Class series covers the basics of photography. This series is intended primarily for beginners and students. This is the first post in the series.
Cameras come in all shapes, sizes, and are designed for various uses. This article describes some of more popular types of cameras used by creative and working photographers.
The Nikon Coolpix P7000 is a compact camera that has a few features similar to a good DSLR, including a flash hotshoe.
Digital Point-and-Shoot (Compact): Usually, when we talk about point-and-shoot cameras, we’re talking about the compact variety designed for quick snapshots. These normally do not have detachable, interchangeable lenses, often don’t have a flash shoe or other features you might find on DSLRs or other cameras. Most point-and-shoot cameras do however offer many features that allow you to take very good images with little effort. Pop-up flash, auto-focus, digital/optical zoom lenses, high-resolution, and program modes (as well as more creative controls) make it possible for you to worry less about camera settings, and put more of your concentration on your subject. That’s always a good thing. While some photographers will tell you that compact cameras aren’t able to give you professional results, the truth is that some professionals have used point-and-shoots for serious work. The downsides of using these cameras are that image quality isn’t as good as you’ll get from cameras with with larger, high-quality lenses and better image sensors.
Canon 7D DSLR
DSLR (Digital Single Lens Reflex): This is what most professional photographers are using these days. Unlike the compact cameras described above, DSLRs offer larger image sensors and the ability to use larger, interchangeable lenses, which tend to deliver better all-around image quality. Having the ability to change lenses means you aren’t limited to a single type of lens for all the images you take. Beyond the ability to switch lenses as needed, DSLRs also have a number of other features like flash unit connections (usually a flash hot shoe, sometimes also a flash cable connector), more advanced creative controls, better durability, and they’re larger so they tend to fit better in your hands. There are many other technological features and accessories you can use with DSLRs that aren’t normally available with point-and-shoot cameras. If you’re interested in doing any professional work, it’s also likely you’re going to need one of these to be taken seriously.
Canon AE-1 Film SLR
SLR (film): This is a fading option as few, if any, major manufacturers are actually making 35mm film SLRs anymore. 35mm SLRs are what the design of modern DSLRs is based on. These cameras use 35mm film which is still available. Unlike with digital sensors, film is generally rated at one specific ISO, so dialing the ISO up and down in a wide range using a single roll of film is really not a workable option with these cameras. If you want to use an ISO of 400 it’s best to use film rated at ISO 400. In some cases, you can “push” or “pull” the film development to accommodate shooting the film at a different ISO than it’s rated, but since the entire roll is developed in one way, at one time, you’d have to maintain a consistent ISO (or exposure) adjustment when shooting. SLRs have many of the functional features of DSLRs but, of course, there’s no digital sensor and there’s less advanced computer assisted shooting, if any. Still, it’s a film camera. If you love film, why not keep one of these cameras around? When you get your film developed you can have prints made, and get digital versions on disc, too.
Yashica Electro 35 Rangefinder
Rangefinder: These usually film cameras, that don’t allow the photographer to see through the lens of the camera to compose shots. These cameras are fitted with some window or other “aiming” and framing device to allow the photographer to compose the shot.
Fujifilm QuickSnap one-use camera
Point-and-Shoot (film): Still available to consumers, even at some grocery stores. These are generally considered disposable or recyclable ease-of-use cameras. They come with varying features and some have a built-in flash. They are fun to use film cameras but offer few if any adjustable settings and much lower image quality than you’ll get with most other cameras. Also, they are range-finders which means you don’t look through the lens as you take photos, you look through a small window to give you an idea of what will be in the picture.
Hasselblad H4 Digital Medium Format
Medium Format: When we refer to medium format cameras we might be talking about film cameras, digital cameras, or cameras that can be fitted with either film or digital “backs.” These are usually used by serious hobbyists, fine art photographers, and professionals when clients demand the highest resolution files for standard commercial work. Shooting high-end fashion and advertising? Then you’re probably going to need a digital medium format camera at some point. Medium format relates to larger image sensors (or film negatives) than you’d get with an SLR or DSLR camera. In the film versions, common sizes are 6×6 cm, 6×4.5 cm, 6×7 cm. Digital medium format sensors or roughly 6 x 4.5 cm. These cameras allow you to use interchangeable lenses. They’re great, so why doesn’t everyone use medium format? Some people don’t like the size, weight, or just generally how these cameras handle. Price is also a huge barrier.
Chambre Monorail large format camera
Large Format: Here we’re talking about huge film negatives — usually 4×5 in. or 8×10 in. depending on the camera. These cameras are large and almost always used with a tripod. Good for portrait work and some commercial applications.
Vintage, Film: Older cameras that have been maintained and/or refurbished in order to work with current film formats and power sources (batteries). What constitutes vintage is subjective, but I like to think of vintage as meaning cameras that are classic but are somewhat rare to find in working condition. It’s fun to use old cameras. They can produce interesting looks that you can’t get straight out of a modern film or digital camera. The Yashica Electro 35 (under the rangefinder heading) is something I’d consider “vintage.”
Toy Cameras: These are usually film cameras. When you see the words Lomography, Holga, Diana, etc. these are what we’d consider toy cameras. They are usually made with a lack of precision, technical consistency, and of plastic components (instead of the glass, metal, and composite materials you’d find in more expensive cameras). The images you get from these can contain evidence of light leaks, vignetting, lens distortion, and overall bad and inconsistent image quality. So, why use them? Because they’re lots of fun!
Instant Film Cameras: If you can find some old Polaroid camera and some type of instant film that will fit in it, then you’ve got something few people still have: the ability to shoot a Polaroid picture. Well, there are other instant camera/film options readily available, too, including the Instax variety offered by Fuji/Fujifilm. Take a photo and have a little, unique print ready instantly. The image quality is not the point with these cameras; these are made for fun and/or simple utility.
Device Cameras: Your phone, your iPad2, or any device that does other things but can produce a still shot will qualify under this heading. Sometimes the quality is amazing, other times not so good. If you don’t want to carry a separate camera around, you probably still have a cell phone that can take a quick picture. Lots of software, usually in the form of “apps” is available to make a simple snapshot look more appealing, or quirky, or vintage. Have fun with these. It’s still photography, no matter what camera you use.
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