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GigaPan Pro User Guide
Frequently Asked Questions
1.
What changes exposure and why should I only vary the shutter speed?
When you capture multiple exposure brackets for each position for the purpose of
capturing HDR images, you vary the exposure by varying the shutter speed and keep-
ing the ISO, and aperture constant. Do not vary the aperture because it will change
the depth of field.
2.
What does EV (exposure value) mean?
An increase of one full exposure value means that you double the amount of light.
You can do this by doubling the shutter speed from one second to two seconds. A
decrease of one full exposure value means that you decrease the amount of light by
one half. One full exposure value less than one second is one half second.
Exposure
Value
Shutter
speed
Canon
Nikon
(*see note below regarding quotations)
3.
What is a simple method of determining the center exposure, number of brack-
ets, and the exposure value separation?
Use an evaluative metering mode to determine the center 'Time/Exposure' setting and
then simply choose three brackets with a larger EV separation such as 1.7 EV or 2.0
EV.
4.
What is an accurate method of determining the number of brackets and the
exposure value separation?
Determine the exposure for the brightest, average, and darkest areas that you would
like to be able to see details. Use the following steps:
•
Change the metering mode to spot mode, if your camera has that capability.
•
Point the camera lens to each area and depress the shutter button half way to
determine the shutter speed that will center the reflective meter marker to zero.
Take note of the shutter speeds as you do this.
•
Determine the distance from the average exposure which you use to set 'Time/
Exposure'. Do this by counting how many shutter speeds settings your darkest
and brightest shutter speeds are away from your 'Time/Exposure' setting.
•
The default setting for shutter speeds in DSLR cameras is 1/3 stop. When you
change the shutter speed three times you have changed the exposure by one
exposure value or one EV.
Set the metering mode on your camera to spot meter
Please refer to your camera's user manual for specific information. See table below for
instructions on setting the metering mode for each of the following cameras.
entire fraction.
-2
-1
1/4 s
1/2 s
4
0"5
4
2
0
+1
1 s
2 s
1"
2"
1"
2"
+2
4 s
4"
4"
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