On Sun, 17 Feb 2002 13:48:28 -0000, "Peter McCall" wrote:

>The comparison shots from the MX300, TRV900 and VX2000 are very interesting.
>However, since I'm not familiar with the scenes shown, which is the 'best'
>or most accurate? (Or is there a narrative somewhere that goes with them?)

I'm so used to looking at images, both still and video,
in judging picture quality that I forget what is "obvious"
to me may not be to others... Not everything, but some things to look for...

- are familiar colors (neutrals [as with concrete], sky
blue or grey, grass-green, skin-color, etc.) rendered
believably, and without color casts or mixed-in tints?
- are bright-color areas rendered with good detail, or
are they "undifferentiated-color" looking (red is the
most difficult)?
- are subtle, near-neutral colors rendered with
differentiation and believable color variation, or
as mostly-grey/brown?
- do bright colors "bleed" outside their expected borders?
- is the picture free of an overall color cast?
- is there a good range of tones, with detail in dark
shadow areas and also light highlight areas, while still
showing good blacks and whites?
- is the overall brightness of the image appropriate
(this can often be modified using camera controls, but
this is often not convenient).
- is a smooth-tone area even in tone across the frame and
to the corners?
- are smooth-tone areas relatively free of color noise?
- is detail and patterning relatively well-shown, with
even detail-level running to the image corners?
- does focus appear correct?
- do bare tree branches against sky look believable, or
do they look odd ("blobby", discontinuous, or
"disappearing" into sky)?
- are contrasty edges free of "halos" (can be white or
black), due to "oversharpening"?
- are near-vertical lines smoothly continuous, or are
there "breaks" or "off-sets", or even "sawtooth"
edges?
- are "moire patterns" evident in textured areas?
- are spurious colors evident in contrasty fine-textured
areas, or areas with near-parallel contrasty lines?
- in the motion video (not evident in frame grabs or
stills), is there a "busy" look, with "flapping"
and "stairstepping" as contrasty edges pass over
scan lines?
- can the camera produce images in low light (and very
low light levels) with acceptable noise, sharpness,
color-balance, and brilliance (blacks and whites)?
- can the picture characteristics be modified in
meaningful ways to shift the image toward better
appearance using on-camera controls?

Keep in mind that people without experience judging
image quality often prefer images that are too "warm"
(with a red or orange bias), too contrasty ("killing"
shadow and highlight detail, but producing a
sharper-looking image), too oversharpened (which also
aids the appearance of sharpness, but it adds an
artificial image characteristic to much of what is
shot), too light (hurts highlight detail and
resolution), and with a picture with color that is
not pure ("looks richer") or is relatively poor in
rendering subtle colors ("looks clean")... Also, many
of the shortcomings mentioned above are more typical
of one-chip camcorders than three, of digital
camcorders than analogue, of smaller-CCD or
megapixel-CCD cameras than those with larger CCDs
and fewer pixels, of some brands compared with others,
etc. There are no perfect images made by video
cameras (and none that is also totally unacceptable),
but some really are better overall than others,
though it may involve a learning process to
appreciate the difference...