Better Light 7 Manuel D’Utilisation

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This digital camera system provides an extremely 

accurate method of verifying correct image focus after 
the device has been inserted into the view camera. 
Focus can be checked and adjusted at any point in the 
image, using data from the CCD image sensor itself. 

Since digital focus verification is done at the working aperture for the scan, any focus shift caused 

when stopping down the lens can also be eliminated.

To utilize digital focus verification, first take a prescan of the subject, preferably with a reasonably 

proper exposure and approximate focus. After any prescan, click on the Focus tab panel, located on 
the main control window. After entering this panel, indicate where the CCD should be positioned 
by clicking in the appropriate location in the preview image area. 

A small rectangle will appear as a 

marker at the selected location (this marker can be repositioned as necessary by simply clicking in the 
new location). After a location has been marked, click the 

button in the Focus tab panel. This 

will position the CCD at the indicated location, and begin displaying focus information. Focus data 
is displayed in both graphic and numeric form; by rocking the view camera’s focus adjustment, the 
best focus can quickly be determined

. This system is so accurate that in many cases, it is possible to 

selectively focus on each color in turn, and in subsequent scans demonstrate that the selected color is 
indeed sharpest (even when using apochromatic lenses). After focus has been verified at one or more 
sites, click the 

To aid in using the Focus panel at a distance from the computer screen, click on the Zoom button. 

This will cause a large graph display to appear. The same information present on the small graphs 
in the Tone panel will be shown in the large display window. Clicking the Stop button will close the 
zoomed focus window.