Manual Control Options
The GX-1L provides manual control of aperture, shutter speed, ISO and white balance, which is typical of DSLRs. Because the GX-1L only has one control dial and relatively few buttons, some controls, such as ISO, require the user to press a couple of buttons in succession for access. Others require a combination of a button and the dial. So, though a given control may be available, it's not quick to find.
Focus
Auto Focus
The GX-1L boasts a 5-point phase-matching autofocus system. The focus points are clustered in a cross shape at the center of the frame. A quick look at the system suggested that it works well in bright and average light, but it's not very quick, and that in dim light and low contrast, it can run into trouble. The GX-1L can be set to AF single, in which it stops focus once it has gotten something sharp; continuous autofocus, in which it continuously maintains focus; and manual focus.
Manual Focus
The GX-1L allows manual focus via the focusing ring on the lens. The viewfinder doesn't snap into focus as well as viewfinders on higher-end DSLRs. Part of the problem may be the relatively dim lens, but the pentamirror does leave the display darker than it would be with a pentaprism.
Metering
The GX-1L has multi, spot and center-weighted metering. Multi takes several separate exposure readings across the frame and then evaluates them to determine the exposure. The system can usually recognize backlighting and other high contrast lighting and make accommodations. The *ist DL's Multi setting works well, so we expect that the GX-1L's will be effective also. Spot reads a small segment of the frame, and is useful for manual mode shooters. Center-weighted metering takes one reading of the whole frame with emphasis on the middle of the frame, and is also sometimes useful in manual shooting.
Exposure
The GX-1L has full manual, aperture priority and shutter priority modes, as well as a program mode which can be manually shifted. On the *ist DL, the exposure compensation control works in scene modes as well as the priority modes. We'll have more to say about the exposure accuracy and options in our full review.
White Balance
The GX-1L offers the basics of white balance for a DSLR: it has an auto setting, a straightforward custom setting and 8 presets. The presets are: Daylight, Shade, Cloudy, Tungsten, Flash and three Fluorescent settings. It would be more convenient if the GX-1L had the option of directly setting a Kelvin setting, or a manual “fine-tune” of white balance, which are features that are creeping into the sub-$1000 market. Panasonic includes white balance fine-tuning on its low-end compacts.
ISO
The GX-1L’s ISO runs from 200 to 3200 in full-stop increments. It can also choose its own ISO in Auto mode. We can't formally test image quality at a trade show, but we can say that 1600 and 3200 look really noisy. The camera has an ISO limit setting, which prevents the ISO from going too high when the ISO is set to Auto, a feature that will be useful for shooting when image noise would be objectionable.
Shutter Speed
Shutter speeds from 30 seconds to 1/4000 are available on the GX-1L, with a maximum flash sync speed of 1/180. Photographers who use fill flash outdoors would rather have a higher flash sync speed than that. The GX-1L also features a bulb setting for even longer exposures. The shutter speed can be set in either 1/2 or 1/3-stop increments.
Aperture
The 18-55mm kit lens for the GX-1L has a maximum aperture range from f/3.5 to f/5.6. Smaller apertures can be set in 1/2 or 1/3-stop increments. But users who are attracted to the GX-1L for its ISO 3200 setting and consequent low-light capability really ought to go for a lens with a wider maximum aperture – f/5.6 really won't do indoors.
