Minolta Dimage 7Hi

Great job. Resolution, detail, and color are all good.

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 Dimage 7Hi performed quite well, at least when I took advantage of its contrast and saturation controls.

The Dimage 7Hi is a somewhat contrasty camera at its default settings, but it does provide a fair range of adjustment in several of its imaging parameters, contrast among them. For this very harshly-lit subject, I dialed the contrast all the way down to -3 units, the limit of its setting. I also boosted the color saturation slightly, about 2 units. (But shot in the "normal" sRGB color space, rather than the "vivid" one.)

The shot at right was taken with a +0.3 EV exposure compensation adjustment, which brightened the midtones to about where they needed to be, although at the expense of some detail in the strongest highlights. As noted above, in addition to the exposure compensation adjustment, I also set the contrast to -3 and the saturation +2 to get the best overall exposure. I chose the Daylight white balance as the most accurate overall, though the Auto setting produced nearly accurate results. The Manual setting was close but slightly warm and greenish.

Skin tones look good, but the blue flowers in the bouquet are a little dark, with purple tints at the edges of the petals. (This is a very difficult blue for many digicams to get right. For reference, the flowers are a fairly pure light navy blue.) The Dimage 7Hi oversaturated the red flowers somewhat, but the remaining color looks pretty good. (The saturation boost seemed to have affected the reds more than the other colors)

Resolution is very good, with a lot of fine detail visible throughout the frame, and fairly strong details in the shadows as well. Details are also sharp, and image noise the shadows is moderate. Overall, a good job here.

To view the entire exposure series from zero to +0.7 EV, see files D7HIOUTCM3SP2DP0.HTM through D7HIOUTCM3SP2DP2.HTM on the thumbnail index page.

Contrast Series (All exposures +0.7 EV, +2 units saturation)
D7HIOUTSP2CON01	D7HIOUTSP2CON04	D7HIOUTSP2CON07

Saturation Series (All exposures +0.7 EV, -2 units contrast)
D7HIOUTCM3SAT01	D7HIOUTCM3SAT04	D7HIOUTCM3SAT07

 Closer Portrait:

Excellent resolution and detail.

Overall results are similar to the wider shot above, and the Dimage 7Hi's 7x zoom lens does a great deal to help prevent distortion of Marti's features. Detail is excellent, with crisp details in Marti's face and hair. The shot at right was taken with a +0.3 EV exposure compensation adjustment, which produced a good overall exposure with only slight loss of detail in the brightest shadows. Shadow detail is strong, with moderate noise. As with the longer shot above, I again used a saturation adjustment of +2 and a contrast adjustment of -3.

To view the entire exposure series from zero to +1.0 EV, see files D7HIFACCM3SP2DP0.HTM through D7HIFACCM3SP2DP3.HTM on the thumbnail index page.

Normal Flash

External Flash (Normal Exposure)

Good intensity and coverage with the built-in flash, only a slight color cast from the background lighting. Excellent operation with a dedicated Minolta external flash unit.

The Dimage 7Hi's built-in flash does a good job illuminating the subject, producing a bright image with good color. The shot at right has a +0.3 EV exposure adjustment, which brings the highlights in Marti's shirt almost (but not quite) to the point of washing out. The background incandescent lighting results in a slight magenta-orange cast on the back wall, and affects Marti's features too, to a lesser extent. I also shot with one of Minolta's excellent external flash units attached to the D7Hi. I aimed the flash to bounce from the ceiling, but also held a sheet of white paper in front of it to catch some of the light, diffuse it, and direct it toward Marti to fill in any shadows. The resulting exposure is much brighter, with slightly better color. (A good external flash unit makes a huge difference on indoor shots like this.)

To view the entire exposure series from zero to +0.7 EV with the built-in flash, see files D7HIINFP0.HTM through D7HIINFP2.HTM.

Auto White Balance

Manual White Balance

Manual White Balance

Good color with the Manual white balance option, but a strong color cast with Auto.

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 Dimage 7Hi's Manual white balance produced the best color, though slightly greenish, while the Auto option produced a very warm color balance. Marti's skin tone is pretty good here, though slightly pale. The blue flowers are dark and purplish, however. (Probably to be expected, considering the light source.)

The main shot has a +1.0 EV exposure compensation adjustment, which is just barely bright. Overall, though, a very nice job.

ISO Series:

ISO Series
ISO 100	ISO 200	ISO 400	ISO 800

Auto White Balance

Daylight White Balance

Manual White Balance

Great resolution, detail, and color.

The Dimage 7Hi's Manual white balance setting produced the best results here, with the most accurate overall color and white value. The Auto setting was nearly accurate, though slightly magenta, and Daylight white balance resulted in a warm, yellow cast. Resolution is very high, as camera picks up a lot of fine detail in the tree limbs and shrubbery. Even the often difficult fine foliage in front of the house shows strong detail. Details are also sharp throughout the frame, with little or no falloff in sharpness in the corners. Nice job.

Far-Field Test

Excellent resolution and detail, with a good 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, and the Dimage 7Hi performed very well here. The tree limbs over the roof and fine foliage in front of the house show excellent detail, especially in the intricate patterns of the leaves and small branches. Details are nice and sharp, with good definition corner to corner. The harsh sunlight tricks the camera into losing some detail in the bright white paint surrounding the bay window, a trouble spot for many digicams. (These shots were taken with the D7Hi's settings at their default values - Dialing down the contrast setting would have helped preserve detail in the strong highlights.) However, detail is fairly strong in the shadow area above the front door. Overall color looks good, and exposure is about right, although there seems to be moderate image noise in the roof shingles (some of this could be the texture of the shingles themselves though). The table below shows a standard resolution and quality series, followed by ISO, sharpness, and color series.

Resolution Series:

ISO Series:

Sharpness Series:

Color Series:
The Dimage 7Hi offers both sRGB (its default, available in both "natural" and "vivid" variations), and Adobe RGB color spaces. Adobe RGB has a much broader color gamut (range of representable colors) than sRGB, and is particularly suitable for professional work in color-managed environments.

Adobe RGB

Natural Color

Vivid Color

Lens Zoom Range

Excellent 7x zoom range.

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 (7x, in this case), and at full telephoto with the digital zoom enabled. The Dimage 7Hi's lens is equivalent to a 28-200mm zoom on a 35mm camera. Following are the results at each zoom setting.

Auto White Balance

Daylight White Balance

Manual White Balance

Slight color casts, but excellent resolution.

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. I felt that the Dimage 7Hi's Daylight white balance setting produced the best looking color here. It looked just slightly warm-toned to my eye, but the overall result seemed more appealing than the pinkish cast of the Manual setting or the slightly cool tones of the Auto option. The slightly warm cast of the Daylight setting results in warm hues in the background, and a slightly yellowish tint to the Asian model's robe. The skin tones look pretty good though. Resolution is very high, with great detail in the embroidery of the blue robe. (This original data file for this poster was only 20 MB though, so cameras like the Dimage 7Hi are definitely capable of showing more detail than the poster has to offer.)

Standard Macro Shot

Macro Shot with Flash

Very small macro area with great detail.

The Dimage 7Hi performed very well in the macro category, capturing a tiny minimum area of only 1.95 x 1.46 inches (50 x 37 millimeters). Resolution is very high, with strong detail in the dollar bill. The coins and brooch are soft due to the very close shooting distance, and the resulting shallow depth of field. There's very little corner softness visible in this shot, just a faint trace in the lower left corner. (The Dimage 7Hi has an excellent lens, with very low distortion.) The Dimage 7Hi's flash also performed well here, with good illumination throughout the frame.

Auto White Balance

Daylight White Balance

Manual White Balance

Good exposure, good color and saturation.

The Manual white balance produced the best color here, with the most accurate white value in the mini-resolution target and large, white color block. Auto white balance also looked good, but was slightly yellow. Daylight white balance produced a stronger warm cast. Exposure is about right, and the Dimage 7Hi distinguishes the subtle tonal variations of the Q60 target well. Colors are bright and vibrant in the large color blocks, though the additive primary colors (red, green, and blue) are just slightly oversaturated. The shadow area of the charcoal briquettes shows good detail, with moderately low noise, and the last steps of both gray scales are just barely distinguishable.

ISO Series:

ISO Series
ISO 100	ISO 200	ISO 400	ISO 800

Color Series:
Here's another example of the "Color" options on the Dimage 7Hi, this time including Black & white and "Solarize".

Color Series
Adobe RGB	Natural Color	Vivid Color	Black and White	Solarize

Contrast Series
The Dimage 7Hi permits very fine-grained adjustment of contrast and color saturation. The three shots here show the ends of its range vs the "normal" setting. (There are a number of steps available between the extremes shown here.)

Contrast Series
Low	Normal	High

Saturation Series
As with Contrast, the 7Hi offers a fairly broad range of color saturation adjustment, in very fine-grained steps. This makes it easy to customize the camera to your specific color preferences.

Saturation Series
Low	Normal	High

Low-Light Tests

Really excellent low-light performance. Great color balance and low noise.

The Dimage 7Hi performs very well under low lighting, capturing bright, clear images. Full manual exposure control and a maximum exposure time of 30 seconds ensure that the camera can handle extremely dark shooting conditions with ease.

The Dimage 7Hi produced clear, bright, usable images down to the 1/16 foot-candle (0.67 lux) limit of my test, with good color at all four ISO settings. (Images have a very slight magenta cast, but overall color is very good.) The Dimage 7Hi automatically employs its Noise Reduction system at slower shutter speeds, which does an excellent job of keeping noise in check. Even at ISO 800, while noise is high, it has a tight, fine grain pattern that makes it less objectionable. The table below shows the best exposure we were able to obtain for each of a range of illumination levels. Images in this table (like all of our sample photos) are untouched, exactly as they came from the camera.

Flash Range Test

A powerful flash, only slight falloff at the 14 foot limit of our test.

The Dimage 7Hi's built-in flash remains bright and effective all the way out to 14 feet from my test target, with only a small decrease in intensity at the furthest distances. Below is the flash range series, with distances from eight to 14 feet from the target.

8 ft	9 ft	10 ft	11 ft	12 ft	13 ft	14 ft
1/125 sec F/3.5 ISO: 100	1/125 sec F/3.5 ISO: 100	1/125 sec F/3.5 ISO: 100	1/180 sec F/3.5 ISO: 100	1/180 sec F/3.5 ISO: 100	1/180 sec F/3.5 ISO: 100	1/180 sec F/3.5 ISO: 100

ISO-12233 (WG-18) Resolution Test

Very high resolution, 1,200 lines of "strong detail". Average barrel distortion, higher than average pincushion though.

The Dimage 7Hi performed very well on our "laboratory" resolution test chart. It started showing artifacts in the test patterns at resolutions as low as 1,000 lines per picture height, in both horizontal and vertical directions, but I found "strong detail" out to at least 1,200~1,250 lines. "Extinction" of the target patterns didn't occur until about 1,550 lines.

Optical distortion on the Dimage 7Hi is rather high at the wide-angle end, where I measured an approximate 0.9 percent barrel distortion. The telephoto end fared a little better, as I measured a 0.4 percent pincushion distortion. Chromatic aberration is fairly low, showing only two to three pixels of 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.)

Resolution Series, Wide Angle

Wide Angle	"Extra Fine" JPEG	"Fine" JPEG	"Normal" JPEG
2,560 x 1,920	D7HIRESWLXF	D7HIRESWLF	D7HIRESWLN
1,600 x 1,200	N/A	D7HIRESWMF	N/A
1,024 x 768	N/A	D7HIRESWSF	N/A
640 x 480	N/A	D7HIRESWTF	N/A

Resolution Test, Telephoto

2,560 x 1,920 (Extra Fine, Tele)

D7HIRESTLXF

Sharpness Series