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on-camera flash. Understanding this is one of the defining moments in
most photographers' progress. Up to a certain point, you just turn on
the flash, or shrug and say, "There isn't enough light." Then, one day--like
a light coming on, if you will pardon the simile--you realize that if
other people can get pictures in next to no light, so can you.
The very simplest option is
just to give longer exposures, using a tripod or other camera support,
including resting the camera on a wall. Even a box camera can be used
for night shots, if you give a long enough exposure. The main things to
watch out for are subject movement--anything that moves during the exposure
will of course register as a blur--and "reciprocity failure."
Reciprocity Effects
Reciprocity failure is the failure of the film to give its full speed
at very low light levels. There may also be color shifts. These effects
vary enormously from film to film. The only way to learn the reciprocity
characteristics for most films is to consult the manufacturer's specification
sheet or web site. For example, one film might require no extra exposure
or special filtration at 10 sec, while another might require 2/3 stop
extra exposure and a very weak filter at only 1 sec.
There are however plenty of
occasions when the somewhat leisurely approach of extending the exposure
indefinitely will not do. At this point, in escalating order of cost,
you need faster film; faster lenses; and (if you want to hand hold the
image) more suitable cameras. Also, regardless of the approach you use--fast
film, fast lenses, tripods, rangefinder cameras, or any combination thereof--there
are techniques of metering and composition that will help you get better
pictures in poor light.
Fast Film
Today, most people use ISO 200 or 400 film most of the time, but there
are plenty of faster options. Taking ISO 400 as the baseline, ISO 800
gives you a one-stop advantage (or one step on the shutter speed dial),
ISO 1600 gives you two stops, and ISO (or more usually EI) 3200 gives
you three stops. The advantages are obvious, but apart from the increased
grain, the other disadvantages are that the faster a film is, the more
it normally costs and the fewer outlets normally carry it.
The fastest true ISO speeds
(1600 and even 3200) are found in color negative. Among color slide films,
the norm is to start with a relatively slow film (EI 400, 200, or even
100) and then "push process" to EIs as high as 1000 or beyond. Fuji's
excellent RSP, for example, is an ISO 400 film that delivers very good
results at EI 800 to 1600, and acceptable results as high as 3200, while
Kodak's Ektachrome 200 is excellent at its rated speed, still superb at
EI 320 (which you get instead of 400 at push 1), very good at EI 640 (push
2) and quite good at EI 1000 (push 3).
Perhaps surprisingly, there
is no great need to worry about the lighting balance. I have used both
daylight-balanced and tungsten-balanced slide films in low light, and
daylight almost invariably looks more natural. If you are shooting print
film, of course, you can adjust the color balance at the printing stage.
If black and white is your
bag, then you have a choice of pushing mid-speed films, or buying seriously
fast films and then pushing them. Ilford's HP5 Plus is normally ISO 400,
but can deliver a true ISO 650 (with full shadow detail) in Microphen
or a similar "push" developer. When pushed, it gives excellent results
at EI 1000 and usable results at 1600; there are even those who push it
to 3200. Fuji's Neopan 1600 is about 1/3 stop faster: in other words,
it's EI 1600, not ISO 1600. An EI or Exposure Index is a working speed
which may or may not correspond to ISO conditions of contrast and shadow
detail.
The seriously fast films are
Kodak TMZ P3200 (ISO 800-1000) and Ilford Delta 3200 (ISO 1000-1250),
both of which work better when pushed than when processed to ISO specifications,
hence the EI 3200 ratings. Depending on what sort of images you like,
both can be pushed to EI 12,500 or even 25,000. For maximum image quality,
most people reckon on EI 2000 to 3200, or 6400 at a pinch.
Fast Lenses
So: you can gain one to three stops, maybe more, by switching to a faster
film. What about faster lenses?
If you use zooms, switching
to prime lenses can give you a lot more speed. With most zooms, f/2.8
is fast, and even f/3.5 is not unusually slow. With prime lenses, f/2,
f/1.8, and f/1.7 are commonplace; f/1.5 and f/1.4 are not unusual; and
f/1.2 and even f/1 are not unknown. In other words, you can gain up to
three stops even as compared with a fast zoom. Combine a fast film and
a fast lens and you can be six stops or more ahead, the difference between
1/60 sec at f/1.4 and a full sec at f/2.8.
After many years' experience
with lenses up to f/1.2--I have never used an f/1 in anger--I have come
to the conclusion that you can go too fast. Depth of field becomes so
small that focusing is problematical. With a 50mm "standard" lens, I prefer
not to go faster than about f/1.8, though I will go to f/1.5 or f/1.4
if I must. I actually sold my 50mm f/1.2 Nikkor because it was of such
limited usefulness. With a 35mm, I love my f/1.4 Leica Summilux (pre-aspheric)
but quite honestly the Voigtländer f/1.7 Ultron is a better lens and I
rarely miss the half stop.
It is also worth knowing that
the "one over focal length" rule is too generous at longer focal lengths,
and too restrictive at shorter focal lengths, so wide angles are a better
bet for low light. I get a higher proportion of sharp shots at 1/30 sec
with a 35mm lens than I do at 1/60 sec with a 50mm, and with a 21mm I
am fairly confident at 1/15 sec and surprisingly often successful at 1/8
sec.
With larger formats than 35mm,
the "one over focal length" rule does not apply at all. For example, I
have an 80mm f/2.8 lens on my 6x7cm Graflex XLRF: about the equivalent
of 40mm on 35mm, insofar as different format shapes can be compared. But
with the bigger negative, which is enlarged less, I have little compunction
about using 1/30 sec, and I know that in desperation I can often get away
with 1/15 sec. This is how pressmen in the days of 4x5" Speed Graphics
got away with 5" (127mm) f/4.5 lenses and ASA 1250 Kodak Royal-X Pan:
rest the camera on your shoulder, lean against a doorway, and you can
often get an acceptable image at 1/5 sec, 1/2 sec, and even a full sec.
On 4x5", 127mm is about the same as 35mm on 35mm.
Low-Light Cameras
Quite apart from the Speed Graphics article earlier, just about everyone
who has reasonable experience of both reflexes and rangefinders will tell
you the same thing: they can hold a rangefinder still for one shutter
speed longer than they can a reflex. In other words, they get the same
sharpness at 1/30 with a rangefinder as they do at 1/60 with a reflex.
Opinions differ about why this
should be--my belief is that it's easier with continuous viewing--but
most people agree it is so. This is one reason why a lot of low-light
aficionados use Leicas or (increasingly) Voigtländers.
Another advantage of a rangefinder
is that its positive split-image focusing beats the "least worst" focusing
position of a reflex. In very low light, when I am shooting 1/30 at f/1.4
or f/1.5 on Delta 3200 at EI 3200, my Leica is fractionally easier to
focus than my Voigtländer, but both wipe the floor with any manual reflex
and with a little care and practice they are a great deal more consistent
and accurate than autofocus, too.
And, of course, most high-end
rangefinder cameras offer a range of fast lenses. Leica wins the sweep
here, with 21mm f/2.8, 35mm f/1.4, 50mm f/1, 75mm f/1.4, and 90mm f/2,
but Voigtländer's 35mm f/1.7 and 50mm f/1.5 are close behind. In addition,
there are independent 21mm f/2.8 lenses (Kobalux) for the Voigtländer
and I rather like my old Russian 85mm f/2 Jupiter which is again Leica-screw.
Techniques
One of the oldest pieces of advice, and still one of the best, for "night"
shots outdoors is to shoot before full dark, while there is still some
light in the sky. This may not make much difference to the exposure, but
it will ensure that the scene looks very much more the way the human eye
sees it. Otherwise, buildings end up black-on-black, and skies are empty.
"Empty" skies are a perennial
problem, and it is often a good idea to use anything you can to ensure
that the top of the picture is not just a black band: fireworks, streetlights,
fairy lights, shop signs, anything.
The same problem can arise
with foregrounds, for that matter, which is why wet roads are the nighttime
photographer's friend: they reflect streetlights, car headlights, and
so forth, adding interest and texture to the foreground.
The meter is going to be fooled
by any picture that is predominantly dark. If the bright areas happen
to coincide with the most sensitive parts of the metering system, the
meter will recommend too little exposure and there will be points of light
against inky blackness. If they are outside the sensitive area, the meter
will recommend too much exposure and the scene will look simultaneously
gloomy and washed out.
Fortunately, most low-light
images work across a surprisingly broad range of exposure--though this
is all the more argument for bracketing, as you often cannot tell which
will be the best. The best bet for determining the base exposure is either
an incident light reading in the principal area of interest or a limited
area meter reading of an important subject. One of the most useful targets
is the palm of your hand, plus half a stop. In extremely poor light, a
useful trick with a handheld meter is to point the bare meter cell (no
incident light attachment) at the main source of illumination, then give
five times the indicated exposure.
If you are shooting negative
film, and having the prints made commercially, the problem of poor exposure
is likely to be compounded at the printing stage. The automatic printer
will render most predominantly dark scenes too light, often with a grainy,
ugly green-gray for the blacks and the light areas completely burned out.
Do not be afraid to ask for a reprint if you can see that the negative
looks more or less normally exposed.
If you fill the frame, of course,
you have less worries about metering and printing, and many of my most
successful night shots have been frame filling. One last thing that I
have always found useful is either to shoot at a very wide aperture, with
correspondingly shallow depth of field and differential focus, or to stop
down well, with the camera on a tripod, for a "deep field" look. Any element
in the picture should be either clearly in focus or clearly out of focus;
the ones where you are not quite sure are generally the least successful.
Above all, remember this. If
you don't play, you can't win. If you're not sure you can get a picture,
try anyway. You may succeed beyond your wildest dreams, or you may fail
completely. Either way, you'll have learned more for next time you want
to shoot when there isn't enough light for any sane photographer to try.
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