Photo Basics; Do I Really Have to Shoot in Manual??
No, you don’t- manual is great when you’re shooting scenes that can easily confuse your camera, or when you want to make sure settings DO NOT CHANGE from one shot to the next, or if you’re a control freak… but otherwise, semi-auto modes and even auto ISO can be great, in combination with an understanding of exposure compensation and knowing WHAT settings you’re in control of, and which your camera will be making.
But first-
What are shutter speed, aperture and ISO?
- Shutter speed- the amount of time that your shutter opens and film or a sensor are exposed to the light, often expressed in fractions of a second, such as 1/125s.
- What does it mean? Faster shutter speeds (1/500s, 1/2000s, 1/4000s…) will help to stop motion. If your shutter is open for a full second, all of the movement within that second will be captured, causing subject motion blur and/or blur from your hand’s shakiness moving the camera itself. On the other hand, If your shutter is only open for 1/2000s, for example, a person, a running dog and even a fast moving athlete athlete will not move significantly in that short fraction of a second, so the subject will be frozen in time, sharp- without risking the shakiness of your hands moving the camera itself either.
- The downside: if your shutter is open longer, 1s for example, lots of light will come into your sensor and your image will get brighter. If your shutter is open for a shorter time, 1/2000s for example, much less light will be able to hit your sensor, so your image will be darker. Put your camera into manual mode (so other settings don’t change) and take pictures at different shutter speeds- you’ll see that the image gets darker as your shutter goes up to 1/500s, 1/1000s, 1/2000s, 1/4000s… This means, you need to adjust other settings to compensate and get the correct exposure.
- Recommendations:
- moving water (on a tripod): 2s or more.
- static subject, handheld camera: 1/focal length (to avoid your shakiness causing blur. For APS-C or MFT, multiply the focal length by the 1.5x or 2x “crop factor”)
- People: 1/125s or faster
- People jogging/running: 1/500s or faster
- Bicycles: 1/1000s or faster
- Other high speed action: 1/2000s or faster
- (These are just recommendations and depend on a number of other factors, so try it out!)
- Aperture- the size of the opening inside your lens. This number, “f-stop,” is actually a ratio representing the physical size of the opening compared to the focal length of the lens, and it will generally give you the same exposure brightness from one lens to another (f2.8 on one less will be about the same as f2.8 on another lens, in terms of exposure). Not that it’s necessary to know this, but, for example: a 50mm lens at f2 has an aperture (opening) that is 50/2=25mm in diameter. A 50mm lens at f5 has an aperture that is 50/5=10mm in diameter.
- What does it mean? A “wider” aperture (smaller f-number, as you can see in the example above) will of course let in more light. So, as you “open up” your aperture (move it to a smaller f-number- see example above), your image will get brighter. As you “close down” your aperture (move it to a larger f-number- see example above), your image will get darker.
- There’s a secondary effect of aperture, and that’s the infamous “bokeh.” This refers to the out of focus background, specifically HOW out of focus it is and in lens reviews, we often talk about the quality of that out of focus area (if it becomes busy looking or if it’s a smooth transition from in focus to out of focus, for example). IF EVERYTHING ELSE IS EQUAL, a wider aperture will give you a more “out of focus” background. I stress “if everything else is equal,” because distance to and behind your subject, focal length, and sensor size can also effect “bokeh.” That’s a different topic.
- The downside/limitation: A downside could be that you just actually want MORE in focus. If you’re in a dark place, and you need to “open up” your aperture to let in more light, you might not like that visual effect (a “shallow depth of field” AKA more “bokeh”). A limitation could be the physical limitation of your lens. Your lens will be marked with an f-number like “50mm f1.8” or “24-105mm f4.” In some cases, the f-number also has a range, like f4-5.6, for example. This number is the WIDEST that your lens can go, physically. If it’s a range like f4-5.6 on a zoom lens, that means that at the wide end of that zoom, you can open to f4 maximum, but at the long end, you can open to just f5.6 maximum. Sometimes, with lenses that have a maximum WIDE aperture of f4 or f5.6, for example, you might not be able to open the aperture wide enough to let in more light and get a bright image in dark places. This is one reason why professionals love lenses that have a max aperture of f2.8 or wider. It lets in more light to shoot in darker situations, without needing to sacrifice other settings like shutter speed or ISO to compensate and balance it out. Also, if your lens DOES have a range, like f4-5.6, for example… this means as you zoom in, the aperture (and your exposure) will change. So be careful. Again, this is a reason professionals like zoom lenses with “constant apertures,” or apertures that don’t change as you zoom the lens. But, they’re more difficult to make, so they’re more expensive.
- Recommendations:
- A 50mm f1.8 lens is a great start for many reasons. 1, it’s often very cheap. 2, it has a wide 1.8 aperture meaning you can get more light in dark places AND you can get more “bokeh.” 3, 50mm is what most people consider a “standard” focal length, so it’s not too wide and not too long, and the amount of blur, or “bokeh,” is also not too extreme, but also far “better” than a kit lens with a more limited aperture. It doesn’t zoom though, so try it out first if you can to see if you like it.
- ISO- the “sensitivity” of your film or sensor. It’s like turning up the volume. It can help, but if you overdo it, the quality will degrade.
- What does it mean? ISO is represented by a number… most often 100 is the “base” ISO. At this setting, your camera will produce the best quality images, technically speaking. As this goes higher, the image will get brighter.
- The downside: if you push it too far, you’ll see the quality of your image degrade. The dynamic range (how much information you have between the brightest highlights and darkest shadows) will decrease, and you’ll see noise or grain in your image. At very high ISOs, that noise can affect color as well. HOW FAR you can go with your ISO will vary quite a lot from one camera to another, but most modern digital cameras could probably go up to ISO 1600 or 3200 without major problems. Noise is also more visible in shadows/dark areas… so the image itself can play a role in what is “acceptable.”
- Recommendations:
- Keep it at the lowest possible ISO whenever possible.
- Raise the ISO when you need a brighter image but you cannot slow the shutter speed (because you’d get motion blur) and you cannot open your aperture any wider (because the physical limitation of the lens).
- Example: shooting basketball indoors; you want a shutter speed of 1/500s or higher to stop their motion. Your lens’s aperture cannot open wider than f4, but at ISO 100, the image is still too dark. Boost your ISO higher until the image is bright enough- it’s your only choice.
There are many factors that affect how you choose each of these 3 settings, which is why semi-automatic modes like Av and Tv help. But, before that, a quick note about “stops.”
A “stop” is like one full step in exposure adjustment. Usually, you can change shutter, aperture and ISO in 1/3 stops… so 3 “clicks” within each full stop. “Stops” between shutter speed, aperture and ISO will affect your exposure equally. So, 1 stop slower in shutter speed (brighter image), 1 stop wider in aperture (brighter image) and 1 stop higher in ISO (brighter image) will all have the same result. So, you can use these “stops” to balance your exposure. For example… if you have a good exposure but want to raise your shutter speed 2 stops (darker image), then you can, A) open your aperture 2 stops to make it brighter again, B) raise your ISO 2 stops to make it brighter again or C) open your aperture 1 stop and raise your ISO 1 stop, a total of 2 stops brighter again. The result: the same good exposure you started with.
- ISO stops are simple- 100 to 200 is 1 stop. 200 to 400 is 1 stop. 400 to 800 and so on (doubling the value). There are 1/3 stops in between these usually.
- Shutter speed stops are similar- 1/100s to 1/200s is 1 stop, 1/200s to 1/400s is 1 stop and so on.
- Aperture, or f-stops, are measured as a ratio like we discussed. So it’s a bit more complicated where the numbers come from, but counting the clicks on your camera’s dial when adjusting them will help if you can’t remember (3 clicks = 1 full stop).
- Lenses are different, so there’s no standard starting point for F-stops, but for example: f2 to f2.8 is 1 stop, f2.8 to f4 is one stop, f4 to f5.6 is one stop, to f8, to f11 to f16 to f21.
So, When do I want Av? Tv? And what are they?
Both are semi automatic modes that let you select 1 or 2 of the 3 settings we just talked about, and the camera will decide the other to get a good exposure (or what the camera THINKS is a good exposure- more in a minute).
Av mode lets you select aperture, and shutter speed is automatically decided for you.
Tv mode lets you select the shutter speed, and aperture is automatically decided for you.
In both modes, you can manually set the ISO, or you can change it to AUTO ISO, when the camera will choose it for you. All cameras will try to keep the ISO as low as possible to maintain quality, and many cameras will have a setting that you can tell the camera a “minimum shutter speed” before it automatically raises the ISO. This is to avoid the camera keeping ISO low, and having a slow shutter speed that results in motion blur. On some Sony cameras, for example, you can set AUTO ISO and min shutter speed to 1/2000s, so the camera will raise the ISO when necessary, but not let the camera go below 1/2000s …great for shooting sports or action where a fast enough shutter speed is important.
Basically, I’d say Av mode is the most popular mode, since the aperture will affect the visual appearance of the photo (that background blur, or “bokeh”). This way, you can select your aperture and the other settings will be adjusted for you. If you don’t have a “minimum shutter speed” setting, just keep an eye on the shutter speeds the camera is choosing so that if it goes too slow (risking motion blur), you can raise the ISO to balance that out.
Tv mode is when shutter speed is especially important- stopping action, for example. I personally think there are far fewer situations to use this- I don’t like the camera adjusting my aperture usually since it visually affects my image. Usually I’d use manual mode with auto ISO, so I can select my shutter speed AND my aperture, and auto ISO will automatically compensate for changing scenes.
Don’t Overlook Exposure Compensation
Like I said before, in these semi automatic modes, the camera will decide what IT thinks the “best exposure” is, and adjust settings to get it. But, the camera is not human. What it’s actually trying to do is average things out to be very… medium. Not too bright, not too dark. But, sometimes your subject is dark! A subject wearing black in front of a dark wall of trees, for example. Sometimes your subject is bright! A small bird with the bright sky behind it filling most of the frame. Well, in these cases you need to TELL your camera, “HEY! Make this brighter than usual,” or “make this darker than usual.” That, is what exposure compensation is. Just telling your camera “BRIGHTER! DARKER!” Some cameras will have this setting accessible by a button, some within the menu and some with a dedicated dial, but it will always be indicated by +/- values. These are also measured in stops- how many stops brighter or darker you want your camera to make it. You can experiment with this a bit, but basically you just want to be careful that you’re not cutting off any of the brightest areas or darkest areas of your image (indicated by your histogram- again, another separate topic). So when shooting a small bird on a bright sky, you might want +1 or +2 stops of exposure compensation (IT’S BRIGHTER THAN YOU THINK, CAMERA!). For a subject dressed in black in front of a wall of dark trees, maybe -1 or a little more (GO DARKER, CAMERA! IT’S SUPPOSED TO BE THAT WAY!).
If you’re in full manual mode, you make these choices all for yourself with shutter speed, aperture and ISO, but in Av/Tv or even Manual with Auto ISO modes… the camera is doing the thinking, so you have to give it a push in the right direction sometimes.
So, finally when do I want Auto ISO??
Basically, when you want to think less. Without auto ISO, in Av mode, for example, your shutter speed will just get slower and slower as the scene gets darker and darker, and that will sometimes mean you accidentally get motion blur if you’re not paying attention and manually raising the ISO yourself. If you set auto ISO, then your camera will kick in and raise that ISO when it gets too dark for you. Less risk, but less control. If the camera starts raising the ISO too high, the image quality can drop without you noticing.
What Makes “Bokeh”
“Bokeh,” or the out of focus background in photos, is a popular topic. But, what is it? How can you control it and what affects it? Let’s take a look.
Basically, 3 things have a major effect on bokeh: aperture, focal length and the relation between the distance from you to your subject and from your subject to the background.
Let’s start with aperture.
Essentially, a “wide” aperture (smaller f-number) will produce a more blurred background (more Bokeh!) IF ALL OTHER THINGS ARE EQUAL. It’s as simple as that. That’s why people call f1.4 and f1.2 lenses “bokeh masters.”
::insert sample pictures::
Next up is focal length.
Without getting overly technical about why, wider lenses have “deeper depth of field” even at the same apertures as longer lenses. This means that the area in acceptable focus in front of and behind the spot you focus on is larger in wide angle lenses.
For example, a 200mm lens at f2.8 might have less than an inch in front of and behind the point of focus that’s acceptably sharp, and outside of that range, it’s all a blur. But a 16mm lens at f2.8 will have a much larger area that’s in focus, in some cases even extending all the way to the distant background.
Of course, the 3rd factor also plays a role here, and that’s distance- both from you to your subject AND from your subject to the background.
Even with a long lens and a wide aperture, if your subject is standing right up against a wall (the background), then it won’t be very blurry. A distant background is the #1 way to make it blurrier. That, or get closer to your subject. Of course, you can’t always get closer to your subject (for example, if you’re trying to frame the head and shoulders for a portrait). You have to use these 2 distances how you can depending on your subject and location, but basically: the closer you get to your subject and/or the further away the background is, the more “bokeh” you’ll get.
Oppositely, if you’re far from your subject or your subject is relatively close to the background, you’ll have LESS bokeh and MORE in focus. So if you’re 25 feet from your subject and the background is 10 feet behind them, you probably won’t get much bokeh/background blur.
Again- remember that the relation between these two distances is important. So if you’re 10 feet away from your subject, but the background is 500 feet away… you’re close in compared to the background’s distance. In macro photography, the background might only be a foot away, but you will be maybe an INCH from the subject, so still… by comparison, that background is “far” and you are “close.” Combine that with something like a 100mm f2.8 lens (long focal length and wide aperture), and you’ll understand why macro photography often has VERY blurred backgrounds. Macro photography often hits all 3 points for maximum “bokeh.”
So, Aperture is the easiest way to get more bokeh, but remember that using long focal lengths and thinking about distance to your subject and the background will also be tools to control that blur and get the images you want. Only have a kit lens? Zoom it out as long as you can and put your subject where the background is far away. Boom. Bokeh city.
The Histogram. What is It and How Can I Use It?
It looks like a mountain. Or it should, at least. And that’s the best way to think of it.
Of course, nothing is that simple… so let’s take a look at what the histogram means and how you can use it in some more detail.
Essentially, the histogram is a graph that represents the brightness of your image from black to white. If you have a spike all the way to the left, that means you have a lot of black. A spike all the way on the right side: a lot of white. BUT- if those spikes are ALL THE WAY at the left or right- it means they’re SO black or SO white, the camera isn’t actually capturing any data there. That means a white shirt? Just white- no texture, folds, shape or shadows. Black hair? You’ll look like an anime character- no strands of hair, just black. So, that’s not good. Let’s avoid that and adjust your exposure when you see the histogram strongly pushing one side or the other whenever possible. (If you’re shooting RAW, depending on your camera, there might be a little bit of room here you can pull back some detail in software like Lightroom, but you need to experiment and know the limits of your camera).
So even if you have a very dark image- a subject in black clothing standing in front of a wall of dark trees… you’ll want the histogram skewed to the left, but not bumping up against the edge.
::example::
If you have a very bright image- a strongly lit subject in light colored clothes with a white wall behind them, for example…. keep that in mind and when adjusting your settings look for a histogram that is piled up towards the right a bit more. But again, don’t let it go too far towards that right side “wall.”
::example::
You’ll still want to experiment with your own camera and style, but remember for example even a very bright sky is not “white” (usually) so if you want to keep some color in it, don’t let it go too far to the right. And remember, shooting in RAW is the BEST WAY TO MAXIMIZE HOW MUCH DATA YOU CAN ACTUALLY SQUEEZE INTO HERE WITHOUT LOSING DETAIL.
So, why did I say it should look like a mountain? Because most of the time it will, and if your camera is in a semi-auto mode, this is what the camera is aiming for. MOST scenes will have some bright areas, some dark shadows, but a lot of “average” brightness in the middle, making the histogram look like a mountain without anything pushing the limits on either the far left or the far right side.
::example::
And finally, why do you need to use this instead of just looking at the screen on your digital camera? Because that can lie. Especially if you’re indoors in a darker room- the image on the screen will usually look brighter than it actually is- the histogram doesn’t lie. Outdoors in sunlight, the image might look a bit dark when it actually isn’t- but the histogram doesn’t lie.
If you’re lucky enough to have a camera with zebras, you can use that as well to judge exposure, but once again, we have a topic for another day.
Scott dumas reviews 