
Taking Sharp Pictures
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There's a few tricks to taking sharp pictures. First of all, let's examine what causes us to take unsharp pictures.
When I said move the camera - I meant
for you to change your perspective!
So, how do you eliminate camera movement? Here are some ideas. First of all, there's a well-known "truism" in photography that goes like this: "The slowest shutter speed you should use when hand-holding a camera is 1/[focal length]." That means, if you are using a 50mm lens, then the slowest shutter speed you should use is 1/50. With a 300mm lens, the slowest shutter you should use is 1/300. Now for the reality: There is NO shutter speed that will eliminate camera movement! Well, it's a matter of perspective. When you shoot with a shutter speed of 1/500, very little camera movement will be observed in a 4"x6" picture. However, blow that 35mm negative up to 24x30 and it's likely you will see some difference between a hand-held picture and one that was taken on a tripod. Also, if you're using a high-quality slow film, it's unlikely you'll be able to use very fast shutter speeds. The point is, no matter what shutter speed you use, learn to hold your camera steady and to press the shutter very gently without moving the camera. Practice without film. It WILL help get you sharper pictures!! Focal Length
There is usually a center-post in most tripods. Don't extend it - make sure it's as low as it goes. The one thing that makes a tripod UNSTEADY is when you extend the center post. You're better off extending the legs than the center post.
Tripods need Help!!
Your Finger: This method has advantages. It's quick and easy. Cable Release: This method is more cumbersome as you need an additional piece of equipment. A cable release is an inexpensive piece of equipment that connects to your camera to trip the shutter without touching the camera. The idea is that when you "touch" the camera, you're likely to move it, even if it's on a tripod. Self-Timer: This method is a way to achieve the advantage of a cable release, without one! You set the camera's self-timer to take a picture - usually in about 10 seconds. The advantage is you don't touch the camera when the picture is taken, but the disadvantage is you have to wait 10 seconds. Not all subjects like to wait!
Here's a radical thought!
What if you were to touch your camera (on purpose) when you trip
the shutter?? Not only that, but you were to use your finger to
trip the shutter?? You don't need any additional equipment, and
it's easy. But, is it effective??
These three images are extreme blow-ups of the center of the frame.
Each picture is of a tree trunk with some vines on it. They were
all taken using a solid tripod, Fuji Velvia film (very sharp), a Nikkor
300mm/f4 lens, a shutter of 1/15 and a Nikon F5 camera (one noted for
it's "vibration-free" mirror - more about that in a minute). The
first image was taken with a cable release. The second was taken
with a cable release and by pressing on the camera directly above where
it mounted on the tripod (actually, this lens has a tripod collar and I
pressed on the lens collar). The third image was taken using the
mirror-lockup feature of the camera AND pressing above the tripod
mounting point.
As you can see, each image is progressively sharper. Mirror lockup
is a great feature, but is only found on very high-end cameras.
You may not have that feature. But, a very useful technique is to
press on your camera directly above the tripod mounting point.
What that means is that if your camera body is mounted on the tripod,
you should gently press on the top of your camera when you take the
picture. If your lens mounts on the tripod, you would press gently
on the lens collar. This seems like a radical thought to many
people, but I can assure you that it works! The mirror vibration
travels up the lens causing movement during the exposure. By
pressing on the camera or lens, you dampen that vibration. The
longer the lens, the more the vibration affects the image. I use a
600mm lens with 1/15 second shutter speeds often when photographing
birds with very slow film and I can get tack-sharp pictures if I
carefully press directly above the tripod mount - of course I usually
use mirror lockup as well with that combination as well.
Lens Sharpness
There is often a misconception that using the smallest lens aperture of
your lens will yield the sharpest pictures. This is WRONG!
The smallest lens aperture will yield the most Depth of Field -
but will not yield the sharpest pictures. Generally, the sharpest
pictures can be had with the aperture that is 3 stops closed from "wide
open". Thus if you have a 50mm/f2.8 lens, the sharpest pictures
will be taken with an aperture of f8:
Autofocus vs. Manual focus...
Autofocus is pretty common among newer cameras. It offers the ability to automatically focus on an object that IT thinks is the subject. If you center your subjects or use a "closest-object" feature to automatically focus on, this MAY work SOME of the time. But autofocus doesn't work ALL of the time. If you like the feature, you should use it, but learn where it fails. After a while you'll get to see where it works and where it doesn't - and where it doesn't, you should revert to manual focus. Personally, I rarely use autofocus. And when I do, it rarely works well for me - and I have one of the top autofocus cameras!
Your pictures ARE sharp!
Your pictures are sharper than you think (maybe :-). If you shoot negative film, you are relying on a piece of machinery to analyze your picture, enlarge it using additional optics (thus reducing the sharpness) and when you get your print back, you're really not seeing the true image that you took. To really understand if your images are sharp, you need to shoot slides and view them on a light table with a loupe.
If you've never done this, the clarity and sharpness of your pictures
may amaze you! You may never want to shoot negative film again.
Unfortunately, printing pictures from slides can be a costly proposition
and they rarely come out as good as the original slide. To get
that kind of results, you have to print them yourself! (More on
that in another session.)
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