Gallery

Boston Globe’s “Big Picture” does it again. Look at this collection of stunning images of Afghanistan:

http://www.boston.com/bigpicture/2009/10/afghanistan_october_2009.html

Stunning. And also sad. Especially, I thought, the “no democracy – we just want Islam” picture – and those are supposed to be students.

And why are they great photographically? I think because they are all a combination of great composition, meaningful subject, and good technique (wide open f/1.4 lenses, available light, and wide angles with a close subject).

Why fast lenses?

Beginners often ask me “why should I buy those lenses with the low F-numbers? Why not buy the standard lens with the 5.6 on the front? They say the lens with the 2.8 on the front is better but I see it takes the same pictures: it’s just more expensive, right?”

Not exactly. The low F-number means  the lens has a larger maximum aperture. This means two things: it lets in more light, meaning faster shutter speed; and the ability, should you choose this, to create blurrier backgrounds.

Here’s my hand at F/11. Recently in Scarborough, while the other instructor, Christine, was explaining the effects of the Aperture setting. My hand is as close as the lens will allow while still achieving focus. I am in Aperture mode (“Av”) and have set the camera to a setting of F/11:

f11

Now the same at f/5.6: a much blurrier background, see:

f56

And now, since I have an expensive lens, I can go even farther, to the extreme end of this lens, namely f/1.4. Meaning very wide open. Meaning very blurry background – and when you look carefully, even foreground:

f14

So that is why people buy these lenses with those low F-number – i.e. “fast”lenses. If you want to blur the background dramatically. Or if you want to have the resulting faster shutter speed (at the same ISO, f/1.4 gives a shutter speed four times faster than f/2.8, and 16 times faster than f/5.6).

Of pixels and millimeters

Reader Dave asks:

“I have a technical question about sensors and pixels… I understand that larger sensor sizes gather more light and thus are better in low light situations and that more pixels will help make a sharper picture… but why do too many pixels make noise and what is the perfect balance? I.e. how many pixels would be good to have on a 1.6 cropped frame sensor?”

Well, the perfect balance will be a challenge. But indeed, this is a balance. Make the sensor larger and you get less noise. Make it smaller with the same number of pixels, and you get [corrected:] more noise. It is not “too many pixels” that make noise. It is “too many pixels stuck together into a small place, meaning they are small pixels”. The smaller you make a phototransistor, the more noisy it gets. So the more pixels you stick in a given area, the more noise.

So to reduce noise you can increase the sensor size, or reduce the area.

That’s why

  • Canon have reduced the pixel count on the G11 compact camera from the G10. Fewer pixels in the same area sensor gives you less noise.
  • My 1Ds MkIII creates less noise than the 7D. They have about the same pixels, but a larger sensor (the 1Ds is full frame, the 7D is 1.6 times smaller) means less noise.

Does that make sense?

Question answered – kind of

BKKphotographer asked:

“Which one living person would you most like to photograph? Which one place or event would you most like to photograph?”

Mmm. I would love to photograph so many people. How do I pick one? Impossible. But I tell you – I would love to shoot Patti Smith. I am reluctant to give the obvious answer of “a celebrity” – but it was her photo by Robert Mapplethorpe on the cover of “Horses”, almost 35 years ago, that awakened my interest in photography. Something that shaped me, in other words.

A place is easier. Again, there are many… but I would love to shoot Afghanistan. I have always thought I would like to be a war journalist: spending time in places like Iraq in the 1980s, when the Iran-Iraq war was on, made me think “the world should see this”. That is another thing that shaped me. So while it’s dangerous, I would do it in a heartbeat.

I’ll come up with others – there will be things that I hit myself over the head withfor forgetting – but these are two off the cuff.

And you?

Bad?

Annie Leibovitz shot the official Obama family portrait. You can see it here:

Obama Portrait

Discussion centres around how truly awful people think this picture is.

I think that is harsh.

The family group composition is good – background, not so much. That background could be more out of focus. And the picture right behind the younger daughter’s head is bad. The cut off picture frames at the top, too. Cut fingers, also. The verticals not being vertical on the right bugs me. Older daughter’s hair is not separated from the background. But awful? The family is nicely positioned. Expressions are good.

All in all, a nice picture that could be better but no doubt Annie had little time and no choice in the location. And the secret service men probably intimidated her. Unless you know the background: easy on Annie, everyone!

What do you think?

So how did the 7D do?

I shot an event yesterday, as said. In a club. A challenging environment.

More pics coming soon, but here’s one more, just to give you a taste of what a good camera and good glass can do.

TRIBE. 400 ISO, f/2.8, 1/60th, at 110mm (70-200 2.8L on a 7D), bounce flash

TRIBE. 400 ISO, f/2.8, 1/60th, at 110mm (70-200 2.8L on a 7D), bounce flash

I shot with two cameras:

  • The 1Ds MkIII with the wide lens (16-35 2.8L earlier, 35mm f/1.4 later)with a 580EX II flash.
  • The 7D with the long lens (70-200 2.8L) and a 430EX II flash.

And they did fine.

The 7D produced some wonderful images – to be posted here with technique tips in the next little while. I am very happy with it.

To start you off, some tips for club shooting:

  • Shoot wide. I needed f/1.4-f/2.8 at 1/30th or less at up to 1,600 ISO.
  • Bring a small LED flashlight so you can see your camera (thanks Alvin, for the tip)
  • Bring two cameras, one long for shots uch as the above, and one wide for the “grip and grins”. Wide should be 35mm on full frame or 24mm on crop cameras, and fast.
  • You can drag the shutter more if you have to.
  • Shoot people with some light in the background
  • Bring batteries
  • Bounce, or if you cannot, then use a Gary Fong lightsphere or a Honl bounce card with CTO gels

And of course: have fun.

Club shooting

Shot a club event last night. Wow, that was tough. No light and no bounce options, and inconsistent flash as a result. In the end, I used:

1Ds MkIII, 1600 ISO, f/1.4, 1/30th, Lightsphere

1Ds MkIII, 1600 ISO, f/1.4, 1/30th, Lightsphere

That is:

  • 1600 ISO
  • f/1.4
  • 1/30th second

That finally gave me the light I wanted. Without the 35mm f/1.4L lens I would have been dead in the water. The other shooters were having to aim their flashes straight at their subjects.. brrr.

Biggest problem all night by far: I could not see any of the controls on my camera. That is how dark it was. Rule of thumb: if you cannot see the camera controls, pictures will be difficult.

Sync or swim

A reminder to all flash photographers: you need your shutter speed to be below the camera’s flash synch speed.

What does this mean? Let me explain.

The flash fires for the briefest period, of course. Like 1/2000th of a second. That is why we call it a flash.

So when it fires, if the light is to reach the entire film or sensor, the shutter needs to be totally open at that point.

That much is obvious. But what is not obvious is that there is an engineering limitation in your shutter. Beyond a certain shutter speed, the camera’s synch speed, the shutter never totally opens. Instead, a small (increasingly narrow) slit travels across the shutter to give each pixel a brief exposure time.That’s cool – the shutter does not have to be super-fast and expensive and you get a fast shutter speed.

But this gets in the way when you are using flash. When you fire during those short exposure times (on most modern cameras, faster than about 1/200th second), the light does not reach the entire sensor. Look at this example I shot to illustrate this, at speeds from 1/200th to 1/1000th sec:

SHUTTER

You can see that as I exceed the sync speed, the light only reaches part of the shutter.

You should also note that especially when using external flashes with Pocketwizards or similar, flash takes time to set up. My 1Ds MKIII has a synch speed f 1/25oth second but as you see, at that speed it is already beginning to cut off. Best stay a bit below your synch speed (I typically set my shutter, when I am using studio flash, to 1/125th second).

(There is a way to overcome that: fast flash, which some high end flash units offer. This continuously, all the time that the shutter travels, pulses the flash at a very rapid rate, so that the slit, as it travels across the sensor, has light coming in throughout its travel time. It works great – do use it when taking flash images outside – but it uses a lot of energy, and hence decreases the range of your flash.)

(Advanced tip: I know of at least one photographer who uses this effect to introduce an electronic version of a neutral density filter or a barn door: he sets his camera to 1/320th second while using flash, and turns the camera upside down. That makes the top part of the image dark, at least as far as the flash part of the light is concerned!)