Faq - Hasselblad HTS 1.5 Manual

FAQ

I was shooting products close-up. The foreground object wasn't
sharp so I tilted the lens as suggested. It became much sharper
but the top of it became unsharp! How can that be? What did I
do wrong?
Fig. 3 shows what probably happened. As you tilt the lens, the
plane of focus tilts too. In this case, as the angle did not com-
pletely coincide with the angle of the plane that the objects were
on, it covered the bottom of the object but not the top. One solu-
tion would have been to use a smaller aperture. You might also
have noticed that the object at the back might have been sharp
at the top but unsharp at the bottom, as in the diagram.
I was using selective focus but didn't like the look of the out of
focus sections. Can I alter them in some way?
The out of focus areas are a result of several factors: the
aperture setting, the proximity of the subject, the nature of the
background, the bokeh of the lens, etc., some of which can be
changed. Try adding special effects filters too or a digital merg-
ing of straight and filtered shots.
I want to produce the maximum quality from one camera posi-
tion to make a huge enlargement. How can I do that?
Very much depending on subject matter, you could try making a
mosaic of overlapping images using shift vertically and horizon-
tally. This would involve changing the orientation of the camera
a little though and so would introduce some distortion issues
and consequently some blending issues in the final image. Nev-
ertheless, using shift should produce a marked improvement on
the standard method.
Some of my images have vignetted. Why is that?
Tilting and shifting to the limits puts demands on the lens and its
ability to cover evenly, in particular when combined. See the table
in this manual (under Creative Opportunities) for restrictions.
Objects in front of the lens (lens shade, filter, accessory holder
etc) can affect results. Even objects behind the lens, such as
when using extension tubes increases the chances of blocking
some of the light rays.
Using a camera with a smaller sensor or with a film magazine
will also have an effect because the capture area differs in size
and its placement within the image circle will be altered.
The simplest solution is to always make a final check with the
lens stopped down to the chosen aperture with all accessories
etc in place, before capture. When using a film magazine, you
also have the opportunity of using the Multi Control facility of
the camera body rear protection cover.
In a selective focus shot I found it difficult to control the
amount of out-of-focus areas over the whole of the image. Why
is that?
Look at Scheimpflug principle illustration to see whether the
depth of field was in fact expanding as the distance from the
camera increased. In these instances the depth is not parallel
as might be expected.
I've seen references to "rise and fall" and "swing" movements
regarding large format cameras. What are they and what do
they do?
Basically, 'shift' equates to 'rise and fall' and 'tilt' equates to
'swing' when these movements are rotated 90°.
Large format cameras are provided with these extra movements
partly to avoid having to mount such a large camera at 90°. The
HTS can be turned as a unit, thereby avoiding this particular
need. Furthermore, as the unit can be rotated freely, it provides
the opportunity to effectively combine movements. For example,
tilting the lens with a 45° rotation is, in effect, producing a
partial swing.
Can I use extension rings?
Yes. They are all compatible. Just remember to check against
vignetting.
39