Directory:  Scans_of_Hy6_Test_Pix_for_Rollei


Two film based tests of the Rolleiflex Hy6 (S/N 596540096) are described below.

The first deals with the autofocus consistently focusing too close regardless of the offset and the
second test deals with the inability of the camera to mechanically (manually) focus at infinity.

If these problems are not in the camera body, they must be in the film back.  It's unlikely that
tree lenses could all have the same problem.  All these symptoms can be explained by the film
plane being too far rearward.



Date of test:  10/18/20.
Film was Ultrafine Ext 100 shot at EI 100 and developed in HC110.
File numbers correspond to frame numbers for first 8 shots.  The last two shots are on another roll.

*  The color picture (focus_test_setup.JPG) shows the test arrangement.
*  Camera was on a tripod.
*  Focus area was set to "small" for these pictures as Eric recommended on 10/17/20.
*  The grid target was centered on the split image in the view finder.
*  All pictures were exposed at 1/12 sec at f2.8.
*  I defocused slightly before each shot so the camera would have to focus every time.
*  Mirror was raised manually before each shot.
*  Camera was set to single focus and was done focusing before I removed my finger from the focus button.

img004.jpg Offset = -30
img005.jpg Offset = -20
img006.jpg Offset = -10
img007.jpg Offset = -0
img008.jpg Offset = +10
img009.jpg Offset = +20
img010.jpg Offset = +30

Test results show that the camera focused too close in all cases with the worst cases being at the most
negative offset.  At no time was the target in good focus nor was did teh camera ever focus behind the target.
This shows conclusively that the film plane is too far rearward and that the offset is insufficient to compensate
for the error in film position.



Test date:  10/18/20 and 10/20/20
Film was Ultrafine Extreme 100 shot at EI 100 and developed in HC110.

*  Camera was set on tripod for all tests.  Focus on each lens was adjusted to the infinity stop.
*  Autofocus was never engaged.
*  All shots were taken with aperture at f2.8.

img011.jpg       Xenotar 80mm at f2.8 at 1/1000 sec (no filter)
img013.jpg       Schneider 50mm at f2.8 at 1/1000 sec (no filter)
img014.jpg       Schneider 40mm at 3.5 at 1/125 sec (red filter w/8X filter factor)

MUST ZOOM IN ON THE CENTER OF THE PICTURES.  Test shows that none of the three images show good
focus in the distance but are actually focused much closer.  Even with the much greater depth of field of the wide angle
lenses, this shows conclusively that the camera is incapable of infinity focus and instead focuses too close.  Again this
suggests that the film plane is too far rearward and an offset adjustment would not correct the issue because the lens
cannot mechanically adjust the focus beyond its hard focus stop.


All scans were done on an Epson V600 at a resolution of 2400 dpi, 16 bit grayscale.  
As with all of these scans, I ignored dust because it wasn’t part of the problem and I didn’t want to waste time dealing with it.