• Review of a New Compact Camera • Sony RX100 III, aka Sony

Fountain Hills Photography Club
Information Series
Bruce Boyce
9/2/14
• Review of a New Compact Camera
• Sony RX100 III, aka Sony RX100 M3
• General guidelines on how to avoid Diffraction
effects, especially in compact cameras
WARNING – THIS PRESENTATION MAY COST YOU
SOME MONEY
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Review of the Sony RX100 III (aka Sony RX100 M3)
“This latest version is headand-shoulders above both its
rivals and its predecessors”
4” x 2½” x 1⅝”
“The RX100 III offers the
best image quality of any
pocketable camera we've
ever seen”
Why the Sony RX100 III ?
• 20Mpxls (5,472 x 3,648)
• 10.2 oz with battery
• 320 pics per charge
• 24-70 mm (FF equiv) lens
• Fast f/1.8 – f/2.8
• Popup EVF, popup flash
• RAW, pro-level controls
• Highly customizable
• Built-in 3 stop ND filter
• Highly capable video
• Wi-Fi, smartphone apps
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Sample Image from the Sony RX100 III (aka RX100 M3)
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Sample Image from the Sony RX100 III (aka RX100 M3)
• 100% crop (1128x752)
• Picture was taken at f/7.1
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“Reflecting Absence” at National September 11 Memorial
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“Reflecting Absence” at National September 11 Memorial
Very sharp, ideal edges !
• 100% crops (image taken at f/7.1)
• At 300 dpi, print is 12” x 18”
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Testing of the Sony RX100 III (aka RX100 M3)
• Resolution testing
• USAF Tribar target; center of camera field of view
• 3 focal lengths : 24, 40, 70 mm Full Frame equiv.
• What is the best overall f/no for each focal length?
• Minimize lens aberration and diffraction effects
For most DSLRs, f/8
is the ‘default’
For small pixel cameras,
the answer is different
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FX100 III Wide setting (8.8mm : 24mm full frame equiv.)
f/2
Optical
aberrations
dominate
f/2.8
f/4
f/5.6
f/8
Diffraction
blur
dominates
Sweet spot
f/1.8
f/11
Much more
blur than in
the f/2 image
Much more
blur than in
the f/8 image
All tribar images are 100% crop
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FX100 III Mid-range (14.5mm : 40mm full frame eq.)
f/2.8
Not quite as
good
f/4
f/5.6
Sweet spot
f/8
Diffraction
blur is
significant
f/11
Diffraction
blur
dominates
• This is a compact camera – f/8 is not the “default”
right answer as it is for most DSLRs
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FX100 III Telephoto setting (25.7mm : 70mm full frame eq.)
f/2.8
Optical
aberrations
dominate
f/4
f/5.6
Sweet
spot
f/8
Diffraction
blur is
significant
f/11
Diffraction
blur
dominates
• This is a compact camera – f/8 is not the “default”
right answer as it is for most DSLRs
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Sony RX100 III Resolution Test Results
• Based on these results, the optimum f/no’s (from image
sharpness perspective) for the RX100 III are;
Focal Length (FFeq /Actual
24 mm / 8.8mm
Optimum f/no
f/2.8 – f/4
40 mm / 14.5mm
70 mm / 25.7mm
f/4 – f/5.6
f/5.6
• For the Sony RX100 III camera, try to avoid f/8 and above
!
What Diglloyd has to say ( http://diglloyd.com/index-free.html )
• “The ideal aperture range for optimal image quality with a
digital SLR often lies between 2 stops down from maximum
aperture and f/8 …
• or f/5.6 for smaller photosite [pixel] cameras.”
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Avoiding Diffraction with Various Cameras
• Diffraction effects are driven by
only 2 things – f/no and pixel size
Q Value Table (Keep Q < 1.0)
Name
Nikon D600
Nikon D90
Nikon D800
Sony NEX-7
Sony RX100
Nikon P7000
Pana. FZ200
Camera Information
# pxls Format Min f/no pxl size
24 MP
Full
6.0
12 MP APS-C
5.5
36 MP
Full
4.9
24 MP APS-C
3.9
20 MP 1" sensor 1.8 - 2.8
2.4
10 MP
1/1.7
2.8 - 5.6
1.8
12 MP
1/2.3
2.8 - 2.8
1.4
built-in
[μm]
2
0.18
0.20
0.22
0.28
0.46
0.61
0.79
2.8
0.26
0.28
0.31
0.39
0.64
0.86
1.10
4
0.37
0.40
0.45
0.56
0.92
1.22
1.57
= Minimum blur
= Significant blur
f/number
5.6
8
0.51 0.73
0.56 0.80
0.63 0.90
0.79 1.13
1.28 1.83
1.71 2.44
2.20 3.14
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1.01
1.10
1.23
1.55
2.52
3.36
4.32
16
1.47
1.60
1.80
2.26
3.67
4.89
6.29
22
2.02
2.20
2.47
3.10
5.04
6.72
8.64
• Also note how the Sony RX100 III has a zoom lens
perfectly matched to the sensor
• RX100 fast lens delivers best quality around f/4 to
f/5.6, corresponding to Q values of around 1.0
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Review of the Sony RX100 III (aka Sony RX100 M3)
• Recommended aftermarket grip by Richard Franiec
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