The Image Contrast Ratio (ICR) chart below combines data from the “Projector brightness calculator” and the “Image contrast calculator”. It shows the correlation between the projector brightness and image quality for respectively dnp Supernova 23-23, dnp Supernova 08-85 and a standard white diffusion screen. The lower chart shows the “image brightness” as a function of the “projector brightness”. In the white area between the min/max lines you will find the recommended image brightness for the simulated display.
Image height
mm
in
Image width
mm
in
Image area
m2
ft2
Aspect ratio
:1
:1
Image diagonal
in
in
Ambient light in room
0-20 Dark room
200-300 Living room, Hotel, Airport, Bank, Auditorium, Conference room
400-500 Office Environment, Shop, Control room
1K-5K Daylight
50K-100K Direct sunlight
0-2 Dark room
20-30 Living room, Hotel, Airport, Bank, Auditorium, Conference room
40-50 Office Environment, Shop, Control room
100-500 Daylight
5K-10K Direct sunlight
lux
ft-c
Ambient light on screen
Rule of thumb:
The light level on the screen is approx. 50% of the light level in the room
lux
ft-c
Percentage of light coming from above
%
%
Horizontal viewing angle
°
°
Vertical viewing angle
°
°
Projector checkerboard contrast
60:1 Fair
80:1 Good
100:1 Very good
150:1 Great
200:1 Excellent
:1
:1
Loss for calibration
Projector manufacturers often optimize for brightness and not for correct color reproduction.
Articles claim 15-20% average loss in brightness for calibration
1-chip projectors claimed to loose 20-40% brightness for calibration
3-chip projectors claimed to loose 5-15% brightness for calibration
%
%
Average lamp efficiency
Definition of lamp life = working hours until 50% effeciency.
75% is about average in lamp life
%
%
Min. brightness on primamy axis
lum
lum
Max. brightness on primary axis
lum
lum
8
7
6
5
4
3
2
1
0
1
2
3
4
5
6
7
8
9
9
SNS 23-23
SNS 08-85
Std. white
Projector brightness (lumens)
8
7
6
5
4
3
2
1
0
1
2
3
4
5
6
7
8
9
9
SNS 23-23
SNS 08-85
Std. white
Max.
Min.
Projector brightness (lumens)
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