Instruction manual

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should plan for a transit time of one hour and allow at least 50 minutes for
assessing the target, obtaining the photos, reviewing the photos, and possibly re-
shooting one photo. Instead, you decide upon a total sortie time of 1.5 hours (an
artificial deadline), launching at 1100 and returning to base by 1230. Now
everyone (crew and mission base staff) is locked into the 1.5 hour sortie. You and
your crew has it in their minds that they have to be back at base by 1230 so the
next sortie using your aircraft can launch on time.
If you’re successful, you’ve saved 20 minutes. However, if you are so mindful
of being back by 1230 that you don’t take time to review your photos before
turning back to base you risk returning without all the quality photos you were
tasked to obtain. Another crew will have to go back to your target to obtain the
photos you failed to get. Instead of taking an hour and fifty minutes to obtain the
photos, it will now take at least three hours to get all the photos!
11.4.2 Vibration
Vibration comes from the airplane, its engine and air turbulence. To reduce
the effects of vibration, hold your camera properly and don't rest any part of the
camera or your body against the airframe. In particular, keep your arms and
elbows from coming in contact with the window sill or armrest. Ideally, the only
part of the airframe that will be in contact with your body is the seat cushion.
Normally the camera is set for the Automatic (or Program) mode, letting the
camera set the shutter speed and aperture. However, if you need to use the
Manual mode, keep these facts in mind:
• Shutter speed is the biggest contributor to sharpness. Since CAP
imaging sorties are conducted at 75 - 80 knots from 1000 feet AGL, the
minimum shutter speed should be 1/250 second.
• You can use very large apertures since there is no need for depth of field
(discussed below). You should experiment to learn the largest aperture at
which your lens is sharp and the highest ISO at which your digital camera
makes clean images. Once you've set ISO and f-stop, use whatever fast
shutter speed you get (he faster the better). Finally, compare these
results against those using the AUTO settings, and use this if possible.
11.4.3 Visibility
It’s best to wait for the best visibility instead of shooting through haze or other
obscuring conditions. Even on clear days visibility is rarely unlimited, so you
always have to adjust to actual conditions over the target.
Haze and fog are the most likely limits to visibility you have to deal with.
Ways to deal with these are:
• When you fly over the target during or after the ID pass, see if there is a
difference between looking straight down at the target and looking at a
slant angle. With haze, lower angles to the target are often better. With
fog, the reverse may be true.