General Points; Scheimpflug Principle - Hasselblad HTS 1.5 User Manuals

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HTS 1.5
Item no.: 3043400
MOVeMenTs
The lens can be shifted 18 mm, either upwards or down-
Creative opportunities
wards, and it can be tilted 10 degrees up or down. Tilt and
shift can be combined according to the diagram.
The HTS 1.5 can provide many opportunities to improve a
normal shot. The whole idea of being able to manipulate where
the plane of focus in the subject lies offers scope for creative
opportunities that are difficult to achieve otherwise. Although
digital manipulation can often provide similar effects it should
hTs settings are presented on camera grip LCd and are
be remembered that not all effects can be created digitally. In
also embedded in the image file.
addition, much time and skill is often required.
A case in point would be the appearance of out-of-focus areas
in a selective focus shot, for example. Here, the bokeh of the
lens also plays a part in the creation of these parts of the
image that will produce unique imagery difficult to replicate
digitally in a realistic manner.
Selective focus
Just as tilt can 'increase' the depth of field (as demonstrated,
only an apparent increase. In reality, a change in angle), it can
also 'decrease' the depth of field by an opposite action. Tilting
the lens 'the wrong way' to define the plane of focus in the
subject in combination with a large aperture setting creates an
effect that displays great emphasis on small, specific areas.
Longer focal length lenses and closer proximity to the subject
increase the effect. The examples here use the same focus and
MaXIMUM TILT
aperture settings, only the tilt angle, and thereby the angle of
The graph shows the maxi-
the depth of field plane, has changed.
mum amount of tilt that can
be used without vignetting as
Tilt and Shift together
a function of the amount of
There can be many cases where combined problems might
shift used.
be solved by the combined solution of tilt and shift together.
format 36×48mm.
For example, an architectural detail on a tall building could be
captured to (a) maintain its perspective by using shift and (b)
isolated from distracting details (selective focus) by using tilt.
Creatively, the combined use can produce some unique results.
Note that there are slight restrictions regarding the combina-
tion of shift and tilt. Check on the chart shown here for a rough
guide to combinations that will not display vignetting.
In this close up of gift foil wrap, you can just discern the direction
of the plane of sharp focus and also the depth of field, chang-
ing according to the direction of tilt. Essentially, the same focus,
aperture setting and lighting were used for all images; only the tilt
(horizontal) setting was altered.
In reality, after tilting, there normally has to be a very slight
adjustment of camera position (and possibly focus), if the same
composition is to be kept. Some subjects, such as illustrated
here, will therefore show different reflectance patterns. The differ-
ence in appearance of the specular highlights is quite marked in
this particular case.

General points

There are various practical points that should be noted when
using the HTS 1.5 that are not necessarily specific to the unit.
Regarding tilt, the most common use is to manipulate the plane
of focus and thereby the direction of the depth of field. However,
depth of field has no sharply defined boundaries. An unsharp
section of an image can look acceptably sharp when reduced
and similarly a sharp section can look unacceptably unsharp
when enlarged. This is commonly experienced today where im-
ages can be instantly checked on the monitor at huge enlarge-
ments. So when tilting the lens, be aware that while improve-
ments can be made, a perfectly sharp image across the whole
of the desired field might not ever be possible. Remember that
perception of sharpness can also be subjective and vary ac-
cording to the nature of the subject matter.
As is standard practice, judgement of the image should made
with the appropriate variables in mind (intended enlargement/
viewing distance/print dpi/etc).
Also, check the focus more often than normal. When the lens is
tilted, you should expect a shift in focus. If you are working teth-
ered you will be able to make very accurate checks, but even
zooming on the digital capture unit display will be of great help.
Remember that some parts of the image that were in focus at
the outset of the shoot might not be covered by the plane of
sharpness anymore when tilting adjustments have been made.
This can be particularly noticeable with taller objects in product
photography (see earlier diagrams).
* Zoom into the image of a test shot on the display to check
focus when untethered.
* Hand held shots with the HTS are possible (in the right condi-
tions), even for stitching.
TILT and shIfT adapTer
General
Only the user can judge what is acceptable in image distor-
tion compared to a 'straight' shot. What might normally be
described as technically wrong by one person is considered a
creative addition by another. It is therefore not possible to warn
against mishap when using tilt and shift. It is wise to remember
the occurrences that can take place so that you then either
induce them or at least be aware of them if unrequired.
Integral automation built into the whole system prevents
exposure miscalculations from the initial estimation, so it is es-
sentially only the visual aspects that need to be of concern.
It is advisable to always check for vignetting. Even when extreme movements
are not used, sensor size, filter holders, extension tubes etc can all combine to
create a situation where vignetting might occur. See FAQ for more information.
This graph shows the maximum amount of tilt that can be used
without vignetting (without lens accessories attached) as a
function of the amount of shift used. Format 36×48mm.
10
Landscape mode
Portrait mode
8
6
4
2
0
0
5
10
15
Shift (mm)
29
www.hasselblad.com
31
* Plan carefully when shooting interiors, for example, if you
intend to use stitching and HDR, remembering to check for
overlapping details and areas.
* Analyze the situation first before making any movements to
ensure the optimal corrective action.
* When using selective focus, check the quality of the out-of-
focus areas produced by various aperture settings.
* The HTS 1.5 uses an integral optical converter to produce the
much enlarged image circle inside the camera necessary. This
consequently produces a factor of 1.5 and so the 28 mm lens
would equate to a 45mm and an 80 mm lens to a 128mm
respectively in terms of effective focal length.
* While the performance of lenses is extremely good in combi-
nation with the HTS 1.5, it should be remembered that when
shifting, the edge of the projected image is being used and is
naturally slightly inferior to the central area.
* When making captures for stitching, the amount of overlap re-
quired for seamless results will depend on the subject matter
and post production software used. Two is normally sufficient
in many cases but three might be advisable for complicated
subjects. See special section in this manual for details.
* The best results should be expected from the 28 and 80 mm
lenses. The 35, 50, and 100mm can also be used for excel-
lent results while the 150, 210 and 300 are not recommended
for critical use. Other lenses and various accessories are
incompatible. See page 2 in this manual for details.
* It is a good habit to make a final check against vignetting
(with the lens stopped down to the selected aperture) before
capture.
33
HC80, Extension ring and HTS 1.5 — Focus was on the ring together with a very wide aperture.
In the top right hand corner of the images you can compare how the specular highlights are recorded according to tilt.
•  In A they are out of focus. 
•  In B they are much more out of focus.
•  In C they are sharper.
Likewise you can compare the apparent depth of field in the center of the image.
•  In A, the depth of field is what you would expect at such close range, extension tube and very wide aperture. 
•  In B, the depth of field appears to be reduced because the plane of focus is not in line with the plane of focus of that part of the im-
age. However, visual emphasis is now on the small section that is in focus.
•  In C, the depth of field appears to be much greater because the plane of focus coincides with the subject in the middle section.   
A
B
Appendix

Scheimpflug principle

In this illustration, the sensor plane and lens plane are par-
allel producing a subject plane that is also parallel.
At the widest aperture the depth of field is very restricted.
The yellow objects are in focus as they are on the same
plane, along with some of the red object. The green ob-
jects are out of focus.
Object in focus
Object out of focus
Image plane
Lens plane
Depth of field does not extend to
the green objects at full aperture
6/8
USER MANUALS
C
30
General points
Scheimpflug principle
Specifications
FAQ
Terminology
32
Object out of focus
Out of focus
here
Object in focus
Subject plane
continued overleaf
34
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HTS 1.5 – 3043400 – 2011 – v3

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