A small photo session
Updated 08.06.2011
When I make photos of my models, I do like this:
The camera:
There are many cameras available. If you have no favourite, the selection
may be difficult. It's always a question to select between a compact
camera and a SLR camera. The SLR (Single Lens Reflex) camera has the advantage that you see the
motive "live" in the viewfinder, seen through the lens. Many
compact cameras have an adjustable LCD screen, as on mine. I am very
found of the adjustable screen, so I often use the compact camera before my SLR
camera for model railway photography. But, normally I use my SLR camera.
Anyhow, you need a good camera with possibilities for manual aperture adjustment. For web
use the resolution doesn't have to be very big, as 72 dot per inch is the same
resolution as the PC screen. Now a days all cameras have a very good
resolution.
Light:
I do have a couple of 500 Watt photo lamps, but for practical reasons I do not
use them (I would have to rig them up in the living room). I do not use sunlight
either, as this often becomes very hard with high contrast. In addition, the
blue sky can add a blue colour to the photos.
I find the best light when the weather is slightly overcast, but with bright enough light to make
shadows. I use one or more white screens (white paper or cardboard, or the bottom
of the bigger white Märklin boxes) to reflect light to the object, to fill the
shadows. We have a conservatory connected to our house, with glass walls on three sides and a
transparent roof, perfect for this kind of light.
Focal length:
I adjust my zoom to max. focal length, on my digital compact camera
28,8 mm (the 35 mm film equivalent is 140 mm). That way you have a very good control of the background and the
perspective.
Focus setting:
Many cameras have a macro setting. It may be an advantage to use
this. If in doubt, make several test shots and check if the subjects are in
focus. Some cameras have a manual focus possibility. In some cases
(e.g. of the subject has a very low contrast) this is an advantage, but modern
auto focus normally does the job very well. This way also close-ups may be
good.
Aperture and depth of field:
Select the aperture as small as the camera permits. On my compact digital camera (Canon Powershot G6)
only f/8. By selecting the smallest possible opening (highest f
number), the depth of field is maximum, but a longer
shutter opening time is required. The higher the aperture number (f/4, f/5,6,
f/8, f/11, f/16), the smaller the aperture opening, the better the focus depth.
At normal focus lengths 1/3 of the focus depth is in front of the focus point, 2/3 behind it.
But,
at short distances, the ratio is close to 1:1.
Remember that the focal distance is measured from the so called film plane in the camera, not from the
front of it.
Stolen from http://www.dofmaster.com/dofjs.html.
Here you can find a lot of information about this interesting subject.
I also
have a digital single lens reflex camera, a Canon EOS 5D. A new world opens, regarding
aperture, compared with a compact camera. I have a 28-200 mm f/3,5-5,6
zoom lens, with the shortest focusing distance of
45 cm. When zoomed to 135 mm actually even a little bit shorter. For model railway
photography, the smallest aperture, f/32, is very good for depth of field. At 200 mm focal
length the aperture is down to f/39.
I also have a 100mm f/2,8 macro lens. It has a minimum focus
distance of 310 mm, which gives 1:1 picture size (1x magnification). The
minimum aperture is f/32.
At 310 mm distance and f/32 the depth of field is only from 304 to 316 mm,
totally 12,5 mm only, at f/11 from 308 to 312 mm, only 4,4 mm. I prefer
manual focus at this short distance.
Sharpness
Many test, and magnification on the PC screen,
shows that the general sharpness of the photo often decreases a bit at smaller
apertures than f/11. This is probably because the light from the subject
passes through a very small aperture opening in the lens, and have to widen out
a lot in a short distance to cover the whole film or sensor.
This means that a macro photography it will always be a compromise between a
good depth of field and a great general sharpness.
Some examples of depth of field, same focal length in all the photos, and the same focus point:
With aperture opening f5,6, 1/10second:
With aperture opening f8, 1/5 second:
With aperture opening f16, 0,8 seconds:
And finally with aperture opening f32, 3,2 seconds:
Exposure metering:
Many cameras have the possibility to select three different metering areas; like average,
centre or spot. I select the spot metering to measure the light only on
the locomotive itself, not including the white background. Another way to
check the illumination, if you have a camera with fully manual adjustment, or
the possibility to lock the exposure setting (by pushing the shutter button half
way down or something), is to use a Kodak Gray Card to measure the light.
The gray card reflects 18% of the light, which is an average of the reflection
from most objects. My camera has a "bracket setting"; the camera
shoots one frame according to the exposure meter, one shot is made one exposure
step down and one up.
Example: f/8 is fixed, the exposure meter
indicates a shutter time is 1/4 of a second, which becomes the first shot, shot
two is at 1/8 second (half time), shot three is at 1/2 second (double
time). This way it's a better possibility to get a good shot.
Tripod:
A tripod is mandatory, as during the above mentioned settings, the shutter
opening time may be up to several seconds. A self timer or a remote control is
very important, to avoid camera vibrations.
In some cases you wish to create special "visions". In this example I used
15 seconds shutter opening time, to show the cabin light and the front light. The
aperture is as small as possible on my compact camera, f/8, to get a best possible depth of field. The smoke
generator is on, but the smoke is not very visible due to the long exposure
time.
Film speed:
If possible, set it to as low as possible, even at a digital camera. My lowest
is ISO 50. Select the best resolution and the lowest image compression.
But, many sources claim that all digital cameras have a "natural" or basic film
speed, for instance ISO 100 or 200. All other speeds, lower or higher, are
made by an electronic alteration, which will reduce the image quality. The
basic ISO setting is known only for a few cameras.
Background:
I use a white background, as far away from the object as practically possible.
If I had a layout, I would probably use a nice part of the layout as background. In this case
the background, a little bit too close, is the bottom of a Märklin wagon box.
Manipulating the photos:
No matter how lucky you are with the exposure, a minor manipulating of the
picture to get the best final result is normally necessary. A good
"photo manipulating" software is required. For use in web-sites
and in other PC screen medias, 72 dots per inch is adequate, also when used with
video projectors. If the main purpose is for printing or magnification, a
higher solution should be selected.
A well known object:
To make sure that several photos becomes as identical as possible, a good idea
is to have one well known object in all the photos, and adjust the photos so
this object becomes identical colour- and light wise in all the photos. In
my case the C-track is the well known object.
Example, my Märklin 3417 NSB 63 2770, the image size is reduced to 72 dpi,
800 x 323 pixels, 284 Kb:
Click on the photo. It is a link to the high resolution photo, 180 dpi, 2991 x 1104 pixels, 3 035 Kb,:
This high resolution photo shows that f8 is not small enough to get a good focus
depth, as the front and the rear of the locomotive is out of focus.