In it's promotional
material for the FZ1000, Panasonic
announced a 5 axis optical image stabiliser system, promising greater
effectiveness than OIS systems previously seen in Panasonic cameras and lenses.
In my early outings with the camera the OIS did indeed
seem effective with a steady EVF image at E400mm focal length and plenty of
nice sharp pictures.
So I ran some
systematic tests My method was to
photograph a page of newsprint, standing, hand held, viewing through the EVF at
a range of shutter speeds from 1/400 to 1 second, with and without OIS engaged.
I used normal type OIS.
I ran the test with the lens at the wide end, focal length
E25mm, at the mid part of the range
E100mm and at the long end, E400mm.
I viewed the resulting files at 100% on screen and recorded
the result as sharp, slightly soft or obviously soft.
Results:
Focal
length
|
Slowest shutter speed giving a sharp picture
|
OIS advantage in EV steps
|
|
|
OIS Off
|
OIS On
|
|
E25
|
1/15 sec
|
0.3 sec
|
2.3
|
E100
|
1/40sec
|
1/5 sec
|
3.0
|
E400
|
1/250sec
|
1/40sec
|
3.0
|
Clearly FZ1000 OIS is more effective than that in Panasonic
M43 lenses.
Discussion:
Safe hand held shutter speeds. The table above might tempt you to try for
some very low hand held shutter speeds. By all means give these a trial. there are two issues to consider however:
1. OIS does nothing to minimise subject movement. If you are
photographing people at 0.3 seconds they are not going to be sharp.
2. The results reported here are an accurate statement of
the shutter speeds which I was able to achieve in my OIS test. However the test
session was in a quiet room, with plenty of time to make each shot. I have
steady hands. I was calm and was able to use optimal technique on each frame,
namely doing mini meditation, controlled breathing, squeezing the shutter
button smoothly at the end of an exhalation.
Out in the real world these ideal conditions will often not
be available. As a result I would not expect such low shutter speeds to be
routinely associated with sharp pictures.
In fact I have found it more realistic to use the following
as slowest shutter speeds likely to reliably produce sharp results if the
subject is reasonably still and I use good camera technique.
Wide, E25mm, 1/25sec
Middle, E100, 1/100sec
Long, E400, 1/400sec
Many readers will immediately recognise these shutter speeds
as the old inverse of focal length for 35mm cameras. I have repeatedly found
that with everyday use, slower shutter speeds, for instance 1/125sec at E400mm will
not reliably deliver sharp photos.
If the subject is moving I have found it necessary to at
least double the (1/focal length) shutter speeds, and to go faster if there is
enough light.
I have noticed on user forums a tendency for contributors to
post photos with the notation "sharp, hand held at half a second" or
similar, with pride and a few exclamation marks. Indeed one of my shots at
E25mm and 1 second was quite decently sharp. But such wonders are flukes, not a
realistic guide to user expectations.
FZ1000 Programme Auto Exposure
(P on the Mode dial. iA has a very similar, possibly the same algorithm) On this camera the P Mode algorithms have a
characteristic which I have not found in M43 cameras. A Mode is the same with respect to shutter
speed and Auto ISO. Indoors as the light level falls, the camera will allow the
shutter speed to fall to a very low speed before shifting Auto ISO above 1600.
That shutter speed is
E25mm, 1/4 sec
E100mm, 1/6 sec
E400mm 1/8 sec
When using the FZ1000 indoors I find I need to be constantly
aware of the shutter speed being selected by the camera in P or A Mode and either switch to S Mode or use a bit of flash
when light levels are low.
Summary The new 5 axis FZ1000 OIS is a definite
improvement over previous implementations of Panasonic OIS technology. I
believe OIS is essential if a camera such as this is to be hand held at the
long end of the zoom range. But it is not a panacea for poor technique and it
cannot achieve the impossible.
excellent preci and very useful info on shutter speeds. I will use it as a rule of thumb.
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