GA645i/Wi vs GA645Zi exposure lock comparison?

[william_f._robinson]

I understand there is a way to aim the i/Wi cameras at something to

set the exposure by hitting some buttons, and then set focus

afterwards. Can this also be done on the Zi? I come from the camera

does the AE lock, and the the photographer does the focusing, school

and want to know if the Zi can be used the same way - separating

exposure setting and focus setting into two steps, in that order.

Thanks in advance.

William F. Robinson

[patrick_drennon]

You may or may not be aware of how the manual focus works on the Zi. There is an AF/MF button on back of the camera. When this is depressed and the master dial is turned it changes the manual focus distance to some distance between 1m and inf(1m, 1.1m, 1.2m, 1.3m, 1.5m, 1.7m, 2m, 2.5m, 3m, 4m, 5m, 7m, 10m, 20m, inf) these are the set distances available for manual focus, it is not infinitly adjustable. There is no through the viewfinder focusing possible outside of AF. That said, it is a two step process but would be difficult to do in the order you describe.

[frank_ward1]

William, I don't think you can perform both operations on the Zi unless you are in the manual exposure mode. I'm messing with my Zi now and can only make independent adjustments by manually setting the exposure first and then locking the autofocus. I use the autofocus lock daily and have never had a problem with exposures. In fact, its consistency astounds me. Frank

 

http://www.culturalvisions.com/

[frank_ward1]

William, just to clarify my previous posting. You can do a two step operation with the Fuji Zi. First, set exposure by dial adjustment in the manual exposure mode by pointing at whatever you want to read as 18% grey. Second, point at whatever you want to focus on and depress the shutter half way. This is an autofocus operation. Third, recompose to your satisfaction and press shutter the rest of the way down.

 

I do not suggest using the manual focus capability because it is only a guestimate system of no practical use in common photo applications. For example, it is only useful if you want to preset your focus at 6' and than shoot street photos without looking through the viewfinder and intentionally keeping your victims at 6' away. Frank

[paul roark]

Having recently taken deliver of a Zi, I just wanted to add that the manual focus is very useful in landscape photography. It allows one to control depth of field, and the zones provided are quite adequate for the job.

 

By the way, a small depth of field calculator is very easy to make with two concentric plastic circles, one with the distance and the other with the f-stops at the appropriate places. Depth of field information is readily available to whip one of these together.

 

Paul Roark

http://www.silcom.com/~proark/photos.html

[paul roark]

Let me elaborate on the original question.

 

Having explored the exposure options of the Zi further, I find both good news and bad news. The bad news is that the metering pattern is inappropriate for the recommended holding position for landscape/horizontal framing. The good news is that there is an easy way to lock the exposure while letting the AF work independently -- the manual exposure mode acts as a lock.

 

As a background, note that the meter is, generally, center-weighted. However, the meter accentuates more than just the center AF-marked region. To avoid a bright sky or background from causing the foreground from being underexposed the meter also accentuates the areas that are toward the bottom and left side of the camera. This works very well with the camera held horizontally (portrait framing).

 

Now the bad news. The owners' manual seems to recommend that for horizontal ("landscape") framing (camera vertical) it is best to hold the camera such that your arms are against your body and the camera is rotated such the right hand side is down. I find this works very well, with both hands holding the right hand grip. Unfortunately, the metering pattern appears to have been designed for the opposite, more traditional 35 mm vertical holding position -- right hand on top. (This made sense for traditional 35 mm SLRs when the left hand was needed on/under the lens for focusing or supporting a telephoto, and the right hand needed to be positioned to advance the film and fire the shutter.) The center-weighted meter of the Zi, however, as was noted above, accentuates a region toward the left side of the camera. If one holds the camera right hand/side up, then the pattern would accomplish the goal of avoiding the bright sky and keeping the foreground in range. However, with the right hand down (recommended) holding position, the meter pattern accentuates the sky, which will likely cause problems in landscape photography.

 

The good news is that locking the exposure and avoiding this problem is fairly easy. The manual exposure dial also acts as an exposure setting lock. So, all one has to do is meter on automatic with the camera in a position that avoids this unwanted accentuation of the sky (or other bright background), and then switch to manual exposure. Switching from automatic to manual mode can be done very quickly with the camera in shooting position, using the thumb on the mode dial lock and the index finger spinning the mode dial wheel to the last/manual position. This locks the exposure while allowing the AF to work as usual.

 

Paul Roark

http://www.silcom.com/~proark/photos.html