Digital Cameras - Pentax Optio MX Test Images
|I've begun including links in our reviews to a Thumber-generated index page for the test shots. The Thumber data includes a host of information on the images, including shutter speed, ISOsetting, compression setting, etc. Rather than clutter the page below with *all*that detail, we're posting the Thumber index so only those interested inthe information need wade through it!|
(This is my new "Outdoor" Portrait test - read more about it here)
The extreme tonal range of this image makes it a tough shot for many digicams, which is precisely why I set it up this way, and why I shoot it with no fill flash or reflector to open the shadows. The object is to hold both highlight and shadow detail without producing a "flat" picture with muddy colors, and the Optio MX had a hard time with the harsh lighting, despite my use of its low contrast setting.
The shot at right was taken with a +1.0 EV exposure compensation adjustment, and the camera's contrast setting adjusted to its "low" value. Despite the use of the low contrast setting, the Optio MX had a hard time with the harsh lighting, losing essentially all the highlight detail on this (admittedly very tough) test. The Auto white balance setting produced the most accurate overall color, as the Daylight setting was reddish, and the Manual setting quite warm and yellow.
Marti's skin tones are a little flat-looking here, with a bit of a brownish-orange look to them, and the blue flowers in the bouquet are rather dark, albeit quite hue-accurate. (Many digicams have trouble with this blue, which is in reality a light navy blue with just hints of purple in it.) Although the colors are a little dark throughout the frame, the hues are actually very accurate. Resolution is moderately high, and details are fairly strong in the flower bouquet and on Marti's hands. Detail is surprisingly good in the deep shadows, but the noise is there is fairly high.
To view the entire exposure series from zero to +1.75 EV, see files OMXOUTAP0.HTM
through OMXOUTAP7.HTM on the thumbnail index page.
Higher resolution and increased detail, but high contrast limits the tonal range somewhat.
Color and exposure are similar to the wider shot above, and the Optio MX's 10x lens does an excellent job of avoiding geometric distortion. The shot at right was taken with a +0.5 EV exposure compensation adjustment. Highlights are bright and slightly blown out from the high contrast, and midtones are dark. Detail is stronger and resolution higher in this shot, though image noise is also high, and obscures the finer details.
To view the entire exposure series from -0.25 to +1.25 EV, see files
OMXFACM1.HTM through OMXFACP5.HTM on the thumbnail
Indoor Portrait, Flash:
Good flash coverage and moderate intensity even at the default exposure, although better results with an exposure boost.
The Optio MX's built-in flash illuminated the subject surprisingly well
at the default exposure setting, though the
overall exposure was slightly low. (Most cameras need a lot of exposure
boost on this shot.) While the default exposure wasn't bad, I found the
best results with a +1.0 EV exposure compensation
adjustment. Color looks pretty good, though the background incandescent
lighting creates an orange cast on the back wall, and also affects Marti's
skin tones somewhat. (The orange cast is much stronger at the default
exposure.) Still, pretty good results overall.
Indoor Portrait, No Flash:
Pretty good color with both Incandescent and Manual white balance settings, and a good exposure as well (though contrast is high).
This shot is always a very tough test of a camera's white balance capability, given the strong, yellowish color cast of the household incandescent bulbs used for the lighting. The Optio MX's Auto white balance setting had a hard time here, producing a strong orange cast. The Manual option produced the best results, though the slight warmth of the Incandescent shot might actually be preferable to some shooters. Exposure was best with a +1.0 EV exposure compensation adjustment (average for this shot), though contrast is a little high. (Here's a shot at the default exposure.) Overall color is slightly dark, especially noticeable in the blue flowers of the bouquet and in the white shirt, which appears slightly grayish. However, skin tones aren't too bad.
Moderately high resolution and good detail. However, high contrast and dark color.
Though a bit cool overall, the Optio MX's Manual
white balance setting produced the best overall color here. The Auto
setting resulted in a moderate red cast, and the Daylight
setting produced a very warm and yellow image. As before, quarter tones
and shadows are somewhat dark and contrast is high. Resolution is good
for the camera's three-megapixel class, with pretty good detail in the
tree limbs above the roof, and shrubbery in front of the house. The image
is also sharper in the corners of the frame than I'm accustomed to seeing
with most consumer digicams.
Pretty good resolution and fair detail, but limited dynamic range.
This image is shot at infinity to test far-field lens performance. NOTE that this image cannot be directly compared to the other "house" shot, which is a poster, shot in the studio. The rendering of detail in the poster will be very different than in this shot, and color values (and even the presence or absence of leaves on the trees!) will vary in this subject as the seasons progress. In general though, you can evaluate detail in the bricks, shingles and window detail, and in the tree branches against the sky. Compression artifacts are most likely to show in the trim along the edge of the roof, in the bricks, or in the relatively "flat" areas in the windows.
This is my ultimate "resolution shot,"
given the infinite range of detail in a natural scene like this. The Optio
MX does fairly well, capturing pretty good detail for its 3-megapixel
class in the tree limbs over the roof, but it's clearly not up to the
levels offered by the best 3-megapixel models out there. On a positive
note though, the image is about equally sharp across the entire frame,
with very little of the softness found in the corners of many digicam
photos. Despite the rather soft lighting from the hazy day this was shot
on, the MX loses practically all of the detail in the bright white paint
surrounding the bay window. This is a problem area for many digicams,
but I'd have expected the MX to do a little better than it did, given
how hazy the conditions were when this was shot. Detail is stronger in
the shadow area above the front door, though still a bit limited. Overall
color looks good, pretty accurately representing what the subject looked
like when it was shot. The table below shows a standard resolution and
quality series, followed by ISO, sharpness, saturation, contrast, and
color filter series.
Digital Filter Series: The Optio MX offers a range of digital color filters, for more creative shooting effects. (Although I personally don't find this sort of feature terribly useful.)
Lens Zoom Range
Excellent 10x zoom range, and a 10x digital zoom as well.
I routinely shoot this series of images to show the field of view for each camera, with the lens at full wide angle, at maximum telephoto (10x, in this case), and at full telephoto with the digital zoom enabled. The Optio MX offers either 4x or 10x digital zoom, and of course, image quality declines in direct proportion to the amount of digital enlargement attained. Still though, if you're only shooting at 640 x 480 for email or web use, digital zoom can be pretty handy. (But really, with the MX's sensor size of 204 8x 1536 pixels, anything beyond about 4x is just "stretching" the original pixels. - At 10x digital zoom, the camera is enlarging just the central 205 x 154 pixels up to whatever image size you're shooting at, making for very blurry images.) The Optio MX's lens is equivalent to a 38-380mm zoom on a 35mm camera. That corresponds to a moderate wide angle to a pretty long telephoto. Following are the results at each zoom setting.
Slightly warm color balance with the Auto setting. Decent resolution and detail.
This shot is often a tough test for digicams, as the abundance of blue
in the composition frequently tricks white balance systems into producing
a warm color balance. Despite slightly warm overall color, I preferred
the Optio MX's Auto white balance setting here,
even though skin tones are a bit warm and orange. The Manual
setting came close too, but was too cool for my taste, while the Daylight
setting was much too warm. The Auto setting's warm color cast gives the
blue background and robe yellow-green tints, but a minor color correction
in post-capture editing software might do the trick. Resolution is high,
and details are strong in the embroidery of the blue robe.
A small macro area with good detail and resolution. The flash almost throttles down enough, but is tricked by the shiny brooch. A very tiny macro area in Super Macro mode, but hard to get light in to the subject.
The Optio MX performed well in its normal Macro
mode, capturing a minimum area of 2.98 x 2.23 inches (76 x 57 millimeters).
Resolution is very high, showing a lot of fine detail in the dollar bill,
coins and brooch. All four corners of the frame are soft, with the right
side of the image being the worst, but this is fairly common in digicam
macro modes, in my experience. In Super Macro
mode, the camera focuses incredibly close, with a minimum area of
0.99 x 0.75 inches (25 x 19 millimeters). However, getting light in to
the subject is nearly impossible at the very closest range. - The MX's
manual states the minimum focus distance in Super Macro mode as "0
cm". That's right, the camera can focus on dust (or anything else)
that's actually touching its front lens element! The Optio MX's flash
throttled down pretty well for the macro area, but the brooch happened
to positioned just right to reflect the flash right back into the camera's
lens. - The resulting glare really isn't the camera's fault.
"Davebox" Test Target
Good color with the Manual and Auto white balance settings. Slight underexposure, and higher than average image noise.
The Optio MX's Manual white balance setting
did the best job here, though overall color is a bit dark, resulting in
a slightly gray white value. The Auto setting
also produced good results, though slightly warm, and the Daylight
setting produced a very warm cast. The image looks just slightly underexposed
overall, although the high contrast means you wouldn't want to have it
too much brighter anyway. The Optio MX does distinguish the subtle tonal
variations of the Q60 target well. Despite the slightly low exposure,
color accuracy is pretty good, with the large tint blocks having pretty
accurate hue values. (The yellow and lime green swatches are rather undersaturated,
while the red swatch is oversaturated. Other colors are pretty much spot-on
though.) The shadow area of the charcoal briquettes shows moderate detail,
and image noise is somewhat high.
Digital Filter Series:
Pretty good performance, with good exposure and color at fairly low light levels. (More than good enough for typical city night shots.)
The Optio MX offers a full manual exposure control mode, as well as adjustable ISO and a maximum shutter time of four seconds. Thus, the camera performs fairly well in the low-light category. In my testing, the camera produced clear, bright, usable images down to the 1/8 foot-candle (1.3 lux) light level at the ISO 400 setting. At ISO 200, images were bright down to 1/4 foot-candle (2.7 lux), and at ISO 100, images were bright as low as 1/2 foot-candle (5.5 lux). Color was good, though slightly warm, with increasing warmth in the dimmer shots. Image noise is moderate at ISOs 100 and 200, and becomes high at the ISO 400 setting. The camera's autofocus system could focus as low as about 1/8 foot-candle, a very good performance, particularly for a camera with no AF-assist light. Overall, the MX would do fine at all ISO settings for typical urban night photography, as typical city street-lighting gives about one foot-candle of illumination. The table below shows the best exposure I was able to obtain for each of a range of illumination levels. Images in this table (like all sample photos) are untouched, exactly as they came from the camera.
(Note: If you'd like to use a light meter to check light levels for subjects you might be interested in shooting, a light level of one foot-candle corresponds to a normal exposure of two seconds at f/2.8 and ISO 100.)
Flash Range Test
Slight underexposure with the flash, but consistent results all the way to 14 feet.
In my testing, the Optio MX's flash illuminated the test target all the way out to 14 feet, without any significant decrease in intensity, although all the shots were slightly underexposed. All in all though, much better flash range than most cameras I test. Below is the flash range series, showing results for distances from eight to 14 feet from the target.
Moderately high resolution, 1,000 lines of "strong detail." Slightly higher than average barrel distortion, and high pincushion as well.
The Optio MX turned in about an average performance for its 3.2-megapixel class on the "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 600 lines per picture height, in both horizontal and vertical directions. I found "strong detail" out to at least 950 lines vertically, 1,050 lines horizontally, so a fair average would be 1,000 lines. "Extinction" of the target patterns occurred around 1,200 lines.
Geometric distortion on the Optio MX is slightly high at the wide-angle
end, where I measured approximately 0.9 percent barrel distortion. The
telephoto end fared only a little better, as I measured a 0.7 percent
pincushion distortion there. (This last in particular is high, but long-zoom
cameras do tend to have more geometric distortion at the limits of their
zoom ranges.) Chromatic aberration is fairly low, showing only about two
or three pixels of moderate coloration on either side of the target lines.
(This distortion is visible as a very slight colored fringe around the
objects at the edges of the field of view on the resolution target.) The
MX's images also lose less sharpness in the corners than I'm accustomed
to seeing in digicam photos. - Overall, it seems that the Optio MX's lens
is of above-average quality.
Resolution Series, 50mm
Resolution Test, Zoom Series
Viewfinder Accuracy/Flash Uniformity
A nearly accurate LCD monitor, just slightly tight.
The Optio MX's LCD monitor is only a little tight, showing about 92 percent frame accuracy at wide angle, and about 93 percent at telephoto. Given that I like LCD monitors to be as close to 100 percent accuracy as possible, the Optio MX's LCD monitor isn't bad, but still has a little room for improvement. Flash distribution is somewhat uneven at wide angle, with falloff at the corners and edges of the frame. At telephoto, flash distribution is more uniform, though with lower intensity.
Optio MX Test Images
Optio MX Specifications
Optio MX "Picky Details"
Up to Imaging Resource digital cameras area
Questions, comments or controversy on this article? Click this link to see what other Imaging Resource readers have had to say about Pentax Optio MX, or add comments of your own!