Sunday, December 21, 2014

Cameras --- Sony WX220 vs A7ii --- close-up, field width, zoom in.

Out of the box --- Sony WX220 versus Sony A7iiK: Close-up, width of field, zooming in.

(Kodak Easyshare M863 --- 3280x1846 pixels, f/2.8, 1/8 sec, ISO-200, no flash, post-processed by Picassa3 pushing Fill light 50%, Highlights 50%, Shadows 25%.)

You must be kidding, right?  How could anyone possibly compare the little Sony Cyber-shot WX220 with the hulking Sony alpha 7 model ii? Well, though much larger than the WX220, the A7iiK (the K means the A7ii comes with the 28-70mm zoom Kit lens) is considered very small and light for a full-sensor (24x36mm) camera. 

The two cameras have many technical things in common: 1080HD, 4K still images, Triluminos color, AVCHD video, SDXC memory cards, HDMI output, Wi-Fi, one-touch sharing, and the Bionz-X processor.  Also, the menus are very similar, even though the A7II has half-again as many menu items.

So, how close can we shoot?  Using the the close-up mode (the flower icon automatically appears with auto-everything when you get close enough), the WX220 can easily focus at a distance of just over 1 inch.
(WX220 --- 4896x2752, f/3.3, 1/30 sec, ISO-100, no flash, 16x9 .JPG format.
At a distance of 1.5 inches, the depth of focus is just over one inch.)

But the A7iiK can’t seem to focus any closer than eight or nine inches.
(A7iiK --- 6000x3376, f/4, 1/60 sec, ISO-250, no flash, 16x9 .JPG format.
At a distance of about 9 inches, the depth of focus looks like two inches.)

 One more close-up example is this --- I wanted to see the “EURO CENT” on the coin.
(WX220 --- 4896x2752 pixels, f/3.3, 1/25 sec, ISO-800, no flash, 16x9 .JPG format.)

This is a close up of a computer screen displaying a close-up of the previous image.
(A7iiK --- 6000x3376 pixels, f/4, 1/60 sec, ISO-1600, no flash.)

How wide is the field of the picture?  The WX220 is this wide.
(WX220 --- 4896x2752, f/3.3, 1/30 sec, ISO-200, no flash, 16x9 .JPG format.)

But the A7iiK shows not quite the same width. This makes sense because the WX220 starts with a focal equivalence of 25mm (4.45mm actual) but the A7iiK lens starts with 28mm, a slightly narrower width.  Notice below that the right and left edges are shaved off just a bit. (Also, the top and bottom are cut off because of the conversion to a 16x9 format.)
(A7iiK --- 6024x4024, f/4, 1/60 sec, ISO-200, no flash, .converted to 1920x1080 .JPG format via Sony’s Playmemories Home software.)

The above conversion from .ARW to .JPG format was necessary because RAW format images (with or without AdobeRGB color space instead of the standard sRGB) often display and print with the colors washed out.  It requires post-processing conversion to recover the apparent color.  (Note: the Playmemories Home software conversion to .JPG does not give you the High resolution and maximum pixels you asked for. but it does keep/restore the color to the picture.)  Since I am not that interested in a lot of unnecessary post-processing work, I’ll happily stick to .JPG and sRGB from now on.

So, what about zooming in?  The WX220 goes from an equivalent 25mm to 250mm (actually 4.45mm to 44.5mm) for an optical zoom factor of 10x.
(WX220 --- 4896x3264, f/5.9, 1/30 sec, ISO-800, 44 mm focal length.)

But the A7iiK can only go from 28mm to 70mm, for a zoom factor of 2.5 (?).
(A7iiK --- 6024x4024, f/5.6, 70mm, 1/160 sec, ISO-500, no flash, .converted to 1616x1080 .JPG format via Sony’s Playmemories Home software.)

Zooming in is one place where we are really comparing apples to oranges (so to speak).  The much smaller sensor in the WX220 requires a narrow field to fit the sensor, so a much smaller amount of forward motion by the lens can easily cover the whole sensor with a much narrower (closer) field of view.  This is one of the great advantages of a small sensor; the optics (lenses) are so much smaller and lighter, they can be built into the camera itself, and never require changing.