Back in April Sony announced the F505V & F55V. Initially confusing, these cameras weighed in with 2.6 megapixels of resolution but both had 3.34 megapixel CCD's (as the label on the side of the camera clearly states).. What was going on here?
Why 2.6, why not 3.34? - Technical answer
After a little further investigation and some maths it became obvious that Sony had simply replaced last years 2.11 megapixel sensor (ICX224AQ) with their newer 3.34 megapixel sensor (ICX252AQ), because the newer sensor was slightly larger (0.933mm larger diagonally) less pixels were available for the image.
Well, I can't explain the marketing decision behind this, sufficient to say that if Sony had stock of the body and lens system from the F505K and were looking for a simple upgrade, this was it.
(as used in the F505)
(as used in the F505V)
|Known as||2.11 mp 1/2"||3.34 mp 1/1.8"|
|Size||Diagonal 8mm (Type 1/2")||Diagonal 8.933mm (Type 1/1.8")|
|Package dimensions||13.8mm x 12.0mm||13.8mm x 12.0mm|
|Pixel cell size||3.9�m x 3.9�m||3.45�m x 3.45�m|
|Total pixels||1688 x 1248||2140 x 1560|
|Effective pixels||1636 x 1236||2088 x 1550|
|Active pixels||1620 x 1220
(diagonal 8.00 mm)
|2080 x 1542
(diagonal 8.933 mm)
|Recommended||1600 x 1200||2048 x 1536|
|Used||1600 x 1200||1856 x 1392|
We've assumed what Sony have done is simply take the ICX224 out of the existing F505 body and inserted the newer ICX252 (package size is identical), if we simply used the previous "Used pixels" the calculation doesn't seem to work, however if we use active pixels instead, we get the following results:
- ICX224: 1636 x 1236 = 6.38 mm x 4.82 mm
- ICX252: 1856 x 1392 = 6.40 mm x 4.80 mm
We're assuming here that the Zeiss lens has been setup to produce an image across the effective pixel area of the CCD not just the recommended area, on the F505 only using 1600 x 1200 of this, and on the F505V using the full available area (at this pixel cell size that could easily be 1856 x 1392).
The diagrams below (top down view) show the relative sizes of each component of the CCD sensor, the final image shows the amount unused by the F505V (the red portion). Diagrams below will appear about three times larger on your monitor than in real life.
|ICX224 1636 x 1236 effective pixel area (green)
6.38mm x 4.82mm
|ICX252 2088 x 1550 effective pixel area (green)
7.20mm x 5.35mm
|Masked ICX252 1856 x 1392 effective pixel area (green)
6.40mm x 4.80mm
|Plastic chip package (13.8mm x 12.0mm)|
|Glass cover (12.7mm x 10.9mm)|
|Effective pixel area|
|Unused (wasted?) pixels on F505V|
Putting things into perspective
- With its 2.6mp the F505V has 34% more pixel area than the F505
- With the full 3.34mp it would have had 64% more pixel area than the F505
- With the full 3.34mp you'd gain 192 pixels horizontally and 144 vertically
The Carl Zeiss Connection
Sony are making a big thing about their Carl Zeiss lens systems, recognizing that consumers are no longer just won over by megapixels, they want image quality and the quality components it takes to produce that. Although the lens systems used by Sony are designed by Carl Zeiss labs they are manufactured in Japan.
So here Sony enter the arena with the S70, a more traditional design than their excellent but rather wild looking F505, it's not too big nor is it pocket sized, but with a nice big, bright F2.0 Carl Zeiss lens they're hoping it'll produce the image quality that educated consumers are expecting.