This post is part
of my ongoing evaluation of the FZ1000. In
due course I hope to discover whether the FZ1000 can replace my interchangeable
lens camera (currently a Panasonic GH4) and a bag of lenses.
In the previous
post I looked at ISO range picture quality. Now it is time to investigate lens
quality.
Method I went about this in two ways. The first was
to go forth into the world and make hundreds of photos at all focal lengths and
apertures using many different types of subject material. Most of these
pictures were hand held.
The second was to photograph my standard test chart on
tripod with timer delay, focus confirmation with MF and peaking. This chart is
a repeating set of classified newspaper adverts affixed to a board. It does not
give any kind of absolute reading but is very useful for comparisons. In this
case I used a Panasonic GH4 with 12-35mm, 35-100mm and 100-300mm zoom lenses
for comparison. These are three of the best zooms in Panasonic's lineup. I have
used them extensively and know they deliver high quality pictures.
To assess resolution/sharpness, I compared pairs of frames matched for E-Focal Length and
Aperture on screen at 100% in Photoshop.
Focal length range I will use "Full Frame Equivalent"
(E) focal lengths throughout this post. The
FZ1000 refers to it's own lens focal lengths in this way by inscription on the
lens barrel and by display in the EVF or
monitor.
The FZ1000 has a focal length range of E25-400mm. This covers most of the combined range of the
comparison lenses which is E24-600mm.
Pricing and
dimensions The Australian retail
cost of the GH4 + 3 lens kit is around
$4600. At the time of writing the FZ1000 is selling for about $1150.
The FZ1000 weighs 865 grams and fits easily into a Lowe Pro Apex
110 AW bag with space for two spare batteries, SD cards and microfiber cloth.
The three lens kit weighs 1965 grams and requires a much
larger bag such as a Lowe Pro Nova 180 AW.
Expectations I think it reasonable that one would expect
the high grade three lens kit to easily best the FZ1000 at all focal lengths.
My findings indicate a more complex comparison with a closer result than I had originally expected.
Results
Sharpness/resolution Best lens indicated. Test aperture indicated. Approximate optimum
aperture for the FZ1000 indicated in
brackets.
Wide angle, E25mm
f2.8. [f4]
Center: FZ1000
Center: FZ1000
Edges: Equal
Corners: 12-35mm
Comment: Any lens which can match the 12-35mm over most of the frame is doing very well. A very good result.
Comment: Any lens which can match the 12-35mm over most of the frame is doing very well. A very good result.
Short Mid range, E70
f3.5 [f4]
Center: FZ1000
Edges: 12-35mm
Corners:12-35mm
Comment: Another good result from the FZ1000. The 12-35mm is really excellent at this focal length and the FZ1000 is close.
Comment: Another good result from the FZ1000. The 12-35mm is really excellent at this focal length and the FZ1000 is close.
Mid Mid Range, E 170mm
f4 [f4]
Center: FZ1000
Edges: FZ1000
Corners: FZ1000
Comment: The comparison lens at this focal
length was the 35-100mm which is a very fine performer. Both lenses delivered
an outstanding result at this focal length but the FZ1000 was just slightly
ahead. Remarkable for a superzoom.
Long Mid Range, E230mm
f4 [f4]
Comment: The comparison lens was the
100-300mm which I know from experience delivers very fine results at this focal
length. Both the FZ1000 and the 100-300mm gave an outstanding result and both were
equal across the frame.
Maximum focal length for the FZ1000, E 400mm f5.0
[f5]
Center: Equal
Edges: 100-300mm
Corners: 100-300mm
Comment: The FZ1000 lens is suffering a bit from loss of contrast right across the frame at this focal length. There is also some loss of resolution towards the edges. The overall result is still good however as shown by the photograph at the top of this post. Careful technique and a bit of help from Adobe Photoshop Camera Raw can produce very satisfactory prints.
Comment: The FZ1000 lens is suffering a bit from loss of contrast right across the frame at this focal length. There is also some loss of resolution towards the edges. The overall result is still good however as shown by the photograph at the top of this post. Careful technique and a bit of help from Adobe Photoshop Camera Raw can produce very satisfactory prints.
Super tele, E600mm f5.6 [f5.6]
For this I used the 100-300mm at
it's longest optical focal length and the FZ1000 on iZoom (JPG) at E600.
Comment: As expected, the 100-300 was
clearly and substantially superior, center, edges and corners. Unlike all the
other focal lengths where there was a surprisingly even contest between the two
kits, this focal length saw a no contest with the 100-300 well ahead. Bird
photographers note.
Corner shading Was not much of an issue with either kit, I
assume it is corrected in the camera software.
Chromatic aberration
and Purple fringing was quite noticeable
from the FZ100 especially in the corners at the wide end. Both are correctable in Photoshop Camera Raw
or Lightroom.
Distortion is being corrected in camera software in both
cases, with the FZ1000 applying almost complete correction.
Flare, sun All lenses can exhibit various streaks, spots
and veiling when exposed to the sun in frame or just out of frame. All four
lenses in this test were so affected. However I made many photos with the
FZ1000 pointed directly at the sun with no ill effects. Flare is very well
controlled in the FZ1000.
Flare, local The FZ1000 showed a sometimes obvious
tendency to flare out a halo around very bright subject elements such as white
boats in direct sun. The 12-35mm can also do this.
Contrast/microcontrast You would expect the GH4 lenses to have
higher local contrast than the more complex lens on the FZ1000, and they do.
The FZ1000 loses contrast toward the long end.
This can make AF more difficult with low contrast subjects and requires extra
sharpening in Photoshop Camera Raw, plus
often a bit of Clarity increase.
Bokeh Out of focus rendition from the FZ1000 is
very smooth in the great majority of photos which I have made. There is an
occasional minor tendency to nisen (double line) bokeh with branches, twigs and
the like but this is not common.
Mechanical Function
Zoom type One would expect a lens like this to be varifocal which means it has to be refocussed after zooming. A parfocal lens stays in focus while zooming. Using manual focus I found that if I focus on a subject at the wide end then zoom in the image goes out of focus. But if I focus at the long end then zoom out the image appears to stay in focus. Hmm... It's a varifocal.
Zoom type One would expect a lens like this to be varifocal which means it has to be refocussed after zooming. A parfocal lens stays in focus while zooming. Using manual focus I found that if I focus on a subject at the wide end then zoom in the image goes out of focus. But if I focus at the long end then zoom out the image appears to stay in focus. Hmm... It's a varifocal.
Image Stabiliser The
stabiliser in the FZ1000 is much more effective than that in any of the
Panasonic M43 lenses which I have used. I
will report on this separately. Fair
warning though, OIS does nothing to counter subject movement.
Zoom For those of us
accustomed to manual zooming, the FZ1000 power zoom comes as a bit of a
surprise. However it works well in practice, with practice. The trick is to
understand that the zoom ring is just an actuator for the zoom motor. Gentle
but constant turning pressure on the ring allows full zoom from wide to long in
about 3 seconds. Twisting the ring faster/harder is counterproductive.
Manual focus This uses
the same ring as zoom after setting the control lever to "Focus". Focus
is motorised. With practice MF works well and is accurate, assisted by peaking
which is well implemented in this camera. However like zooming, Manual
focussing requires practice and familiarity with the behaviour of the actuator
ring. This can be a bit disconcerting at first as the position of the ring is not
directly related to the focus movement of the lens elements.
Decentering I cannot
remember buying a zoom lens in recent times without some small or larger degree
of decentering. This occurs when the lens elements are not located in the
optical pathway in exactly the correct position to very fine tolerances. My copy of the FZ1000 is a bit soft on the
right side at mid zoom and a bit soft on the left side at full zoom. Closing
the aperture one stop minimises the problem.
Summary The FZ1000 lens has performed well above my
initial expectations. It is capable of making highly detailed photos
across the focal length range.
For all focal lengths except E400mm and E600mm it performs
at a level comparable to the three comparison M43 zooms, especially in a large
central area of the frame where most critical subject information is located.
I am investigating strategies for optimising sharpness/resolution
at E400 and E600 and will report on these in an upcoming post.
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