Archived posting to the Leica Users Group, 1999/09/06
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I checked and on my OM4Ti, the highlight button places the highlight two stops above the gray point. For E200 slide film, this is about the right placement for the brightest highlight for which texture is just discernible. This two stop offset can be easily changed with the exposure compensation dial. The offset will stay changed until you move the compensation dial again. There is no need to change the ASA setting. On a more general point, I find that the OM4Ti implementation of multiple spot metering is fantastically convenient and accurate. It basically allows you to apply zone system techniques by pressing a single button, without ever moving your eye away from the view finder. This is the one feature that I sorely miss when I shoot slide film in my M6. It is a feature I would welcome in a future improved M camera, if it could be included without a loss in durability and repairability. Up to eight spots can be metered, and the metered values are clearly displayed as little diamonds above an exposure bar graph which is visible in the finder. (The bar graph displays a long range--about 10 stops worth). You can tell at a glance if you will be able to accomodate all the exposures within the input dynamic range of your film. Metering is very rapid, since the spot meter button is just to the left of the shutter release. With the camera set on automatic, the OM4Ti automatically sets the shutter speed by averaging the EVs of the measured spots. You can bias the metered average either with the exposure compensation dial, or by simply metering the same spot more than once (which will move the average closer to that value.) You can have the camera remember the resulting exposure and use it on all subsequent shots by toggling a MEMO lever which is just forward of the shutter release. This is useful if you want to set up a constant exposure for a sequence of shots, as in street photography where you will not have time to meter each shot separately, or in macro photography where you want to take a number of shots with slightly varying composition, but the same exposure. As an example, I often spot meter a bright textured highlight, and spotmeter a textured shadow spot. If the two values are too far apart (more than about 4 stops for E200), then I bias the exposure twoards the highlight by spot metering the highlight again. This is much quicker to do than it is to explain! You are just aiming the camera and pressing the spot metering button while you look through the viewfinder. With the camera on Manual, the metered levels are displayed, and you get to place them relative to the gray point by hand. (If I am not in a rush this is my preferred mode of working.) Note that to make these techniques work, you do need to know the dynamic range of your film, and where you like to place textured highlights--there is no replacement for photographic knowledge and taste. Certainly the two stop placement for highlights is not going to be correct for any print film that I know of. Unfortunately I don't know how Leica implements spot metering in the R8, so I can't compare the two approaches.