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Getting good focus is critical to getting good pictures.
No matter how good the lens is, no matter how much you sharpen in post-processing, nothing compares to a photo
shot well in the camera. Especially in a camera with the super-zoom reach of the DSC-H1, H2, H5, H7 and H9.
The autofocus of the H-Series cameras is extremely effective and fast (faster with each new generation) - if you
set it up appropriately and use it correctly.
Autofocus Setup
In the Setup/Camera Settings menu, set the AF Mode to "Monitor" or "Single", but not "Continuous"
(there is no "Continuous" mode in the H7 and H9, they use Predictive Autofocus instead).
Continuous Mode keeps hunting for focus even after you half-press the shutter button. It never stops. It's
designed to continue focusing on fast-moving subjects (like bicycle or auto races) and doesn't even work very well
there. The idea is that the subject may keep moving between the time you half-click and full-click the shutter
button. Continuous focus keeps on looking, in case the subject has moved. The problem is that while the AF speed
of the camera is pretty good, it isn't fast enough to recapture focus on a fast-moving target in the short time
between a half-click and a full-click. The result: In Continuous AF Mode, you may get lots of blurred pictures.
I did.
Single Mode doesn't attempt to autofocus until you half-press the shutter button. That's fine for
taking pictures, but it's not at all helpful for composing them. Especially with a long-zoom like the H-Series
cameras, where you may be searching for a subject miles away that's completely invisible in a mist of lost focus.
You can repeatedly half-press the shutter button to force the camera to re-acquire focus.
Monitor Mode autofocuses while you compose, and then locks when you half-press the shutter button.
I recommend Monitor Mode for its benefit to composition.
Camera Focus Modes
In order to focus properly, either you or the camera has to "read" your scene, determine what is to be
in focus and adjust the lens to ensure that the area you want to be sharp is sharp!
The H-Series cameras, like most other digicams, use a "contrast" method to autofocus (DSLRs generally
use "phase-detection", a different method). In order to determine focus, the camera has to find all the
edges in the target area and evaluate them for sharpness. That's pixel-by pixel. The H-Series' autofocus can be
very, very fast or relatively slow, depending on two factors:
1) The contrast detail in your scene. Scenes with no contrast
can be very slow to autofocus. Hence, the cameras can "hunt" a bit in low light.
2) The size of the area you tell the camera to check. The larger the area, the slower the autofocus.
The H-Series cameras offers four camera settings (three
of them automatic) that you can use to determine and ensure sharp focus. The mode you select will effect not just
the accuracy of focus, but the speed of autofocus as well.
You access these options by clicking the Focus button
on the top of the camera until you get to the focus
type you want.
Multi-Point Autofocus
This is represented by the "wide brackets" in your display. When you compose a shot, the camera, using
some undefinable magic, picks what segments of your scene will and will not be in focus. When it does, it displays
one or more of three boxes within the brackets to let you know what area(s) it selected. In the F828, multi-point
was pretty good. It's not so good in the early H-Series. As a number of people have reported (including myself),
it rarely picks what the user wants to focus on. It is also the slowest of the focus methods, since it has so much
calculation to do.
On the other hand, the Multi-Point AF in the H7 and H9
is superb. Much smarter than the earlier versions, and with more focus points (9), it almost always finds the right
subject and does so very, very fast. Fast enough, in fact, for excellent burst-mode Sports photos.
Multi AF Mode - Note wide brackets (H1)
Same in H9.
Center Autofocus
You know you've selected Center autofocus when the camera displays a mid-sized square in the middle of your
screen. Aim the box at your subject, half-press to achieve focus and then move your camera to compose the picture
the way you'd like it to be. Center autofocus is pretty good. Think of it as an "average" focus since
it uses a relatively large area to determine focus without using the entire frame. This is moderately fast and
fairly accurate.
Center AF Mode - note square with brackets (H1)
Flexible Spot Autofocus
This is what I generally use. Flexible Spot focuses on a very small area that is mobile - you can use the camera's
four-way switch to move the selection box around your scene until you pick out the area you want to focus on. Or
you can use the half-click method outlined in Center Autofocus above.
Flexible Spot is very, very accurate. You can point this little box at a garden and get a single flower (or even
a bee!) in focus even though everything around it is out of focus.
Flexible Spot AF also gives you the fastest performance on the H-Series cameras. The camera only has to calculate
using a very small area. Therefore, it is very fast. I recommend this setting for most situations!
Flexible Spot Mode - Note small brackets (H7 and H9)
Manual Focus
Manual Focus is problemmatic in any electronic viewfinder camera. Neither the EVF nor the LCD has sufficient
resolution for you to really tell if you're in focus or out. Make sure "Expanded Focus" is turned on
in the Setup Menu. When you focus manually, the image size is doubled in the viewfinder, which makes it appear
much closer and makes it easier to see if the subject is in focus. When you switch to Manual Focus, you'll see
a distance scale at the bottom of the display. Use the left and right buttons on the four-way switch on the back
of the camera to adjust the focus. Warning: This requires practice!
Another way to use Manual Focus is to autofocus on anything in the same plane you want to focus on, then click
the focus button to change to Manual Focus mode. The camera will retain your Autofocus setting. Think of this as
"Autofocus Lock". This is excellent for repeated shots of moving subjects where you want to cut autofocus
lag down to nothing: birds in flight, auto races, etc.
WARNING: Some people have complained about blurry
pictures, not realizing that they were in Manual Focus mode and hadn't focused at all! If you don't see brackets
or a box in the middle of your display, you are in Manual Focus mode.
A common mistake is to think that the crosshairs in the middle of your display is spot focus. It is not! That's
for metering, not focus!
In manual focus mode, you'll also see a "hand" icon. You'll also see the word "Set" next to
it in the lower left portion of your display unless you're already in "Set" mode.
 .
Manual Focus (H1)
Manual Focus (H7 and H9)
Manual Focus Peaking
The H2 and H5 have a remarkable new feature to help you
determine whether your picture is in focus. Remember, you're only seeing about 4% of the total pixels in your picture
on either the viewfinder or the LCD. It's hard to find edges if they're not displayed.
Manual Focus Peaking finds the edges for you. Using the same techniques the camera uses to perform autofocus, the
H2 and H5 display a bright blue line around any and all edges that are in focus. This takes away a huge amount
of the "guesswork" that can result in disastrous out-of-focus pictures.
Unfortunately, Manual Focus Peaking was omitted from the H7 and H9.
Predictive Autofocus
The H7 and H9 have a marvelous new feature that was only
available, prior to these cameras, on DSLRS: Predictive
Autofocus.
Predictive Autofocus kicks in whenever you shoot burst
mode and in single shot mode, between the half-press and full-press the shutter. You start with a half-click to
acquire initial focus. The camera identifies your subject, determines if it's moving, calculates where it should
be when the photo is exposed and adjusts focus to accomodate the movement.
You can focus on a runner coming toward you, fire off a
round of ten shots and each of them will be in focus without the camera having to opticially re-acquire focus between
them.
The same effect happens if you half-click on a runner coming
toward you. When you fully-press the shutter to grab the shot, the camera calculates any movement that should have
occured since you half-pressed the shutter button and adjusts the focus accordingly.
Not only is this a great feature, but it works really,
really well in the H9. Calculating the focus mathematically is much, much faster than acquiring it optically. Predictive
Autofocus is the fastest autofocus possible.
This feature makes burst mode usable for the first time
in an H-Series cameras. And it dramatically improves the shooting experience and shooting results for sports, children
and pets.
Focus Assist Light
The Focus Assist light is supposed to help you achieve focus in bad lighting conditions. I recommend turning it
off unless you're focusing in a situation so dark that the camera cannot achieve focus. In my experience (and I
can't explain this), all the H-series cameras seem to hunt for focus when the orange assist light is turned on.
Much more than they do without it. Experiment on your own, but I found that autofocus performance increased dramatically
in low light when I turned it off. Remember, it's only good out to about 10' to 12' from the camera, anyway.
Getting Contrast
As I mentioned earlier, the key to autofocus is contrast. Sometimes your scene does not have sufficient contrast
in it to autofocus quickly - or at all! One of the first indoor tests I did with my first H1 was pointing my camera
at the sheet on my bed and attempting to autofocus. Well, it didn't take forever, but it did take a good long time.
Why? No contrast. White on white.
But when I moved the camera to point to an area where the edge of the pillow (and its shadow) met the bedsheet,
the camera focused almost instantaneously!
If you have trouble getting autofocus to lock, move the camera to a point where you can see a distinct line, a
place where light and dark come together in the same plane as your subject. Half-click the shutter. The camera
should acquire immediate focus. When it does, move the camera back to compose your picture and complete your shutter-click.
Autofocus Performance
In any autofocus mode, except "Single", your camera is continually hunting to find sharp, well-defined
edges to lock onto. The more pixels it has to check, the more lines there are to check, the less contrast available,
the slower the autofocus will be. So, keep the focus area small (Flexible Spot) and do your initial focus on a
friendly area of your scene. There's nothing worse than getting the opportunity at the shot of your life and you
can't get the camera to autofocus! Or even worse, you get the shot, get home, and it's too far out of focus to
fix.
Fortunately, the H-Series cameras almost never lock on wrong focus and very rarely fail to autofocus. And with
decent contrast, their autofocus is one of the fastest among digicams.
Practice using both Autofocus and Manual Focus. Just a few hours playing with your camera with attention to focus
could save you from many disasters later.
Next: Chapter 2 - Image Stabilization
Return to White Paper Introduction and Contents
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