Five Megapixel Cameras

Minolta DiMage 7

 

Pros

Cons

High Resolution

Slow Auto Focus

7X Optical Zoom with Macro

Slow Furnished Software

Versatile

Some Clumsy Ergonomics

Good Color

Strange Accessory Problems

Excellent Support

Nonstandard USB interface

Electronic Viewfinder

 

 

 

Summary

The DiMage 7 is one of several five megapixel cameras being offered in the $1,000 price range. The Minolta is probably the most versatile of the crop, offering more capability than most users will need. It is also a somewhat more complex camera that will tend to appeal to advanced users. Picture quality is very good (sample image), while ease of use is fair.

 

User Experience

Clearly the high resolution is the biggest draw for this camera. With 4.95 million pixels, 2568 x 1928, it can produce images that rival 35 mm. It is somewhat puzzling that the specifications and advertising for this camera claim 5.25 million pixels in the CCD. Where are those those extra 300,000 pixels?

 

The 7X optical zoom is sharp, and because of the high resolution significant cropping is possible to increase telephoto range. The maximum aperture is f/2.8 at 7 mm and f/3.5 at 50.8 mm. This is equivalent to a 28 – 200 mm 35 mm lens because of the smaller size of the CCD. The lens does macro at 50.8 mm only to a minimum focus of 0.25 meters from the focal plane. Horizontal field of view is 50 mm at this setting. The  manual focus ring at the base of the lens could be bigger and work a little faster.

 

The electronic viewfinder, which can be rotated 90 degrees, is a definite plus in my view. Other users can expect to have a strong reaction too, but theirs may be either positive or negative. Like most digitals there is no range finder so help with focusing is always welcome. The use of a 122,000 pixel viewfinder display provides this through aliasing. When a high-resolution image is sampled at low resolution it is aliased to lower frequencies. This produces fringes which,  when maximized, are the optimum focus. This is helpful on manual focusing and also when auto-focus doesn’t work, true of all auto-focus systems at least occasionally. My reaction to the DiMage’s viewfinder was initially very negative, as I found the fringes visually disorienting and unattractive. After a few weeks I have learned to love them for there usefulness.

 

A monitor LCD is also available on the back of the camera and is often handy. One focusing wrinkle is magnification. If you push the magnification button the viewfinder image shows a magnified area (4X) that is displayed on the monitor LCD. When you look through the viewfinder you see the whole field with a brighter magnification rectangle. When you look at the monitor you the magnified view. This is a good idea. but it takes about a half second to do it and I find it a little clumsy. I would have preferred the magnification to appear in the viewfinder and for a faster, smoother operation.

 

An electronic viewfinder has one other compelling advantage. You see the exposure calculations displayed real time. You can do this on other digital cameras with monitors, but I prefer to use the viewfinder and find it speeds up finding the correct exposure.

 

The exposure metering is good, with an automatic zone like mode, a center weighted mode, and spot. These work well and produce well exposed images with little effort. The DiMage 7 uses menus. This is fine for infrequently used options, but I use the spot meter a lot and would really prefer a faster way to change metering mode. Using the menu button and then the jog button three times and then hitting the menu button again is not something I want to do several times an hour.

 

I have other ergonomic issues with the camera. The presence of a computer often generates complexity and the DiMage 7 takes this to new heights. The manual required three pages of drawings just to show where all the button are. The use of so many buttons doesn’t bother me so much as the fact that I have no choice in how they are arranged or what they do. The virtue of a computer is that the controls can be customized to suit the user. With complex cameras this is more important. So far as I can see, camera manufacturers have not caught on to this, although scientific instrument makers have been doing it for twenty years.

 

The camera uses Compact Flash cards (Type I and II) allowing storage of up to a gigabyte (only a 16 Mbyte card comes with the camera). The image formats supported are jpeg (several quality levels), a video format (called AVI), TIFF, and a raw proprietary form. You can store one TIFF image on the 16 megabyte card furnished with the camera. Software is furnished for the Mac or PC to convert the raw form into TIFF. I tried the Mac software only. The digitizer is 12 bit but this depth is only available in raw. The software must be used to convert to TIFF. The software works fine but is unbelievably slow. I have not used the software except to convert raw images to TIFF. There is very little support for editing 48 bit deep images on computers so far. Any serious editing in Photoshop requires converting to 24 bit.

 

The camera comes with a nonstandard USB interface that cannot coexist with a hub. This means you must dedicate a USB interface to the camera. I used a compact flash Firewire reader for most of the time, but did test the USB on a Mac and a Window machine and it works, albeit very slowly. A 256 megabyte compact flash card takes about 30 minutes to download from the camera while the same card can be read in a minute on Firewire. The decision to use USB and not make it compatible with other devices, is an unsatisfactory aspect of the DiMage 7. Other cameras in this price range are also using the USB, My recommendation is to use a firewire reader. You cannot control the camera over the interface, or back up settings or restore settings. Using a reader is much more convenient than disconnecting everything else before connecting the camera.

 

The instruction manual describes the functions of the camera clearly. It also describes available accessories. I was immediately attracted to the ring light, Macro Ring Flash 1200 with Macro Flash Controller. This would greatly enhance macro work, so I ran down to my local camera store to try one out. Did not work at all. Even with max exposure control and a 2 stop neutral density filter it was still at least 4 stops overexposed. The dealer had no idea what could be wrong. So I called Minolta’s support number, and quickly learned that there are two “Macro Ring Flashs 1200 with Macro Flash Controllers” and I was using the “old” model. The dealer was able to figure this out only after I described the problem and he researched it in Minolta’s dealer catalog. Minolta use of 18 character describion for this flash is not specific enough to allow the customer to order with confidence. I find this unsatisfactory. The correct strobe can be custom ordered, but even an expert user will not get it right the first time.

 

Buying Advice

If you need a five megapixel camera with macro and 7X zoom the Minolta DiMage 7 is the only camera in the price range that delivers. If these capabilities are not important then you may be happier with the Nikon or Fuji. Caution about available accessories is wise.



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