Chuck' Doswell's Outdoor Photography Advice
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Chuck says....
First of all, I often use a polarizing filter, but not always. I do NOT
generally use a "Skylight" or "UV" filter ... but I have been considering
it for some time of late, having damaged lenses in various ways and having
noted how much clarity my vision gets from the UV filter in my
prescription sunglasses.
Image clarity depends on many factors, and of course, I am not scanning and
posting images I have taken that do not have clarity! That is, I do not
show off my failures. I offer the following thoughts:
- Use good quality lenses. For many of us using Canon (me!) or Nikon
equipment, this means we tend to stick with Canon or Nikon lenses, as op-
posed to buying "third-party" lenses (e.g., Sigma, Spiratone, Cambron, etc.).
It's not that those lenses are NECESSARILY inferior, but I like to stick with
the lenses made by my camera's manufacturer.
- Use good quality filters, sparingly. A filter is another optical device be-
tween the subject and the film (the lens is one). The more devices in the
chain,the more likely you are to introduce distortion.
- Use a tripod for virtually every shot.
- Always ensure that your lens is focused, usually on infinity for skyscapes.
- In cases where your shutter speed is between about 1/30th and 1 second, it
is advisable to lock up your mirror (in an SLR 35 mm) before you expose. In
this range, the image is likely to be affected by the shock of the mirror
flipping up during the exposure.
- Long lenses used to bring distant objects up close will typically involve a
contrast loss, due to the intervening distance. It's better to get closer
and use a shorter lens. Although zoom lenses have improved greatly in the
last 10 years, a fixed focal length lens is almost always sharper than a
zoom lens, and usually has fewer elements inside (see #2).
- All else being equal, use f-stops near the upper middle of the range:
f8 or f11. Most lenses perform best in this range in terms of sharpness
and contrast. It is best to avoid the extremes of the aperture range at
either end, but especially so at the larger apertures (smaller
f-numbers). A wide-open lens typically has substantially inferior
sharpness and contrast to one that is stopped down.
- For most slide film, a slight underexposure (on the order of a
half-stop) produces the best, most saturated color. I use Fuji Velvia for
most of my daylight shots ... I use Kodachrome 64 for lightning shots at
night .. see my home page for more discussion. Using slow film (ISO 100
or less) means fine grain, which translates into image clarity. Since I
do not use print film, I have nothing to recommend along that line.
- Be aware of the sorts of situations that produce the best images.
There is no way to describe how generally to do this ... practice,
practice, practice! If you cantrain your brain to SEE and not just to
"look" then it can help you in this directly.
- The weather influences clarity a lot! In the relatively dry, clean
air of the Great Plains, High Plains, and Rocky Mountains, you are more
likely to get the right sort of conditions for image clarity than in the
hazy, polluted air of the Eastern third of the country.
- I can offer little or no advice to users of cameras that do exposure
automatically. I am so old-fashioned, my cameras have a mechanical
shutter! If you are using an automatic exposure camera, as far as I'm
concerned, you're on your own.