Canon 7D, EOS Flashes, Lenses, Canon, Canon 60D, Nikon

Zone Auto Focus, The Good, The Bad And The Ugly

Please note that there is no ugly part. I just liked how the title sounded by adding the word ugly. I am too weak to resist the opportunity to do a bad pun.

The auto-focus is the most complex problem in a modern camera. It has to be right, accurate, repeatable and all this in real-time. Canon needed a solid reply to Nikon's CAM3500, the AF module introduced with the Nikon D300 and the Nikon D3 family. So what Canon did is to provide 6 different ways of using the auto-focus system? Each focus mode has it's strength, it's weakness and pitfalls. It's not that simple.

Lens Hood

Last weekend, I went “shooting” owls. I've been going to Reifel for BIF. My first owl. A barn owl, tagged. I took a grand total of 396 photos in maybe less than 10 minutes, basically 3 big bursts. I could swear that I saw smoke coming out of the camera or the compact flash card. I was using my “trusty” 70-200/4IS, mostly at f/5.6. I had to use ISO 1600, to get an almost decent shutter speed. I was using the single point autofocus.

White Balance Bracketing

The Canon 7D, like most “pro” cameras, has so many options for setting the white balance, that it's dizzying. Like almost all digital cameras, you can set the white balance to daylight, shade, cloudy, tungsten, white fluorescent, and flash. You can even set it to whatever you want.

The Canon 7D even has a white balance bracketing. You press the shutter once, and the 7D will take 2 or 3 different photos with a different white balance. The Canon 7D will take the “current” white balance, and bracket with either a blue/amber coloring or magenta/green coloring.

Problem Focusing With Spot AF

I use the Single Point Focus for around 60% of the photos. I use the Zone Focus for around 30% of the photos. The rest of my photos are made with the other modes: expansion or spot. I don't think that I've ever used the 19 points AF.

The other day, I was taking photos of a very “deep” beach. I wanted to get the focus right, time to switch to Spot-AF. I won't get it anymore precise. But Nooo, it doesn't focus, it hunts. I can't get the “darn” AF to work properly. What's wrong? I recently did the micro-adjustment, what gives?

  • First, I ranted and raved.

No Autofocus! Dead! Kaput

Dead! I can't focus with my “70-200”. What happened? Did the lens die? Did my Canon 7D die? I don't know. But it's dead and no auto-focus. The manual focus seems to be working. It works when “chimping” on the LCD. So it looks like it's the auto part of the focus that doesn't work.

Next lens on the camera, the auto-focus works. Relief! It's either the lens or the combination of the camera and the lens. What's wrong? I pull the backup camera, a Canon 30D that was very cheap and bought it just for those occasions, and the auto-focus doesn't work either.

Long Exposure Noise Reduction

The longer the exposure, the noisier the photo. This is based on physics. There's no way around it. You like it, you don't like it, the longer the exposure, the noisier it will get. This applies to all camera manufacturers: Canon, Nikon, Olympus, Pentax, Sony… So how do we get around it?

Canon, has a method to finding the noise and then removing it from the photo. In the Canon 7D's case it is:

C.Fn II -1: Long exposure noise reduction

  • 0: Off: disabled. You will either live with the noise or use some external software like Nik Software DFine.

sRGB vs Adobe RGB (1998)

The Canon 7D supports 2 colour spaces:

  • sRGB
  • Adobe RGB (1998)

So which one to use? That will depend on what further processing you will be doing.

sRGB

The colour gamut of sRGB is around 35% of the visible colours specified by CIE, the International Commission on Illumination. The colour gamut is still wide enough for almost all applications.

Missing AF point on display

I have noticed that most of the times, when I chimp the photos, I see the autofocus point displayed in red on the LCD. But sometimes, 15% to 20% of the times, my Canon 7D doesn't show the autofocus point used.

Not being a complete idiot, at this point, I have figured out that it must be something that I did. So after a whole bunch of testing and reviewing a of photos, I found what I did:

  1. I have removed the focus from the shutter, and moved it to the back with the AF-ON button.

Sharpening In The Camera

What makes the Canon 7D so special is the customization. I'm currently on working to have my 7d prepare my coffee and warn me when it's getting to strong.

Another common customization is the picture style. The style includes the sharpness, the saturation, the contrast and the colour tone. All these styles are done “in camera”. With the various picture styles, you can set the sharpness from 0 to 7. To me, a sharpness of 3 looks like a Canon 5Dmk2.

The only problem is that the “in camera sharpness” only works with JPEG photos.

Spot AF Mode

I've been experimenting with the spot autofocus mode. As far as I know, Canon introduced the Spot AutoFocus with the Canon 7D and ported it to the Canon 1DMk4. The spot focus is available on all the 19 auto focus points. You can even select which spot focus point to use with the joystick.

According to Canon:

A couple of important notes about Spot AF:

  1. While the AF point size is definitely reduced compared to ordinary Manual AF point selection, **it’s not the tiny square you see in the finder.
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