1. Test overview.

This test is used to pre-adjust the Voffset of the 135 Film carrier so that the scanned image does not include dark edge in top or bottom. An precise adjustment of Voffset will be made later.
This pre-setting is to be made only if test 135 Cal Pre-V-Offset On Edges failed. It becomes necessary to carry out the sharpness adjustments.
For this, the scanner will scan a target film and will determine the centre of the film, which will correspond to Voffset.
Note : 135 Film is made of 2624 pixels top in High Resolution, and the CCD of 6000 pixels, you must decide on which part of the 6000 pixels of the CCD is to be measured. It is on this part that the calibration will be made.
If Pre-Voffset is incorrectly adjusted that can cause problems of automatic detection of cross in the sharpness test.

2. Test conditions.

This test relates to the 135 Film carrier inserted in the scanner.
The 135 Film carrier must be inserted in the scanner to carry out this test.
Colour Target Film must be used for this test (ref 070 100 415A) :
The acceptance of the test is automatic.
The value of Voffset is saved in the file im1500data.ini, in chapter FILM_CARRIER_135, line CENTREING_VERTICAL_OFFSET.

3. Pré-requis.

• 135 Pre-Sharp Test is accepted to ensure that the image is sufficiently sharp.

4.Test realisation.

Cliquer sur RUN to carry out the test. A message will be displayed requiring to enter the cross theoritical value which is in the centre of the film (written down by hand on film). Click then on OK. Another message will be displayed asking the insertion the colour target film. When the film is inserted (caution : watch for the direction of film), click on OK.
The scanner will go on scanning as many time as necessary the first film exposure so that 2 consecutives Voffset values are sufficiently close to one another (8 pixels).
The Voffset finding is done by automatically seeking the position of the cross which is in the middle of film, and by comparing it with its theoritical position (see Automatic crosses detection for more information on this subject).
At the end, the final value is displayed on the screen. This value will be saved.

5. Test acceptance.

No acceptance criteria for this test : the value found is the value saved .
If this test is accepted it is problematic if test 135 Cal Pre-V-Offset On Edges is not accepted.
The Voffset value can be positive or negative.

6. Other affected tests.

If the pre-voffset is incorrect, the detection of crosses in the sharpness tests may no work.

7. Trouble shooting.

None.