I have an opinion on the contrast and flare etc with a little testing I did,
which I can share another time. Suffice to say the higher the dynamic range of
the sensor, the worse the star bursts look shooting directly a led flashlight
beam (sun etc), apart from any differences in reflection of light off the
sensor surface. A camera with a low sensitivity sensor will look much better
than a high sensitivity one for example,at the same exposure fstop/shutter
speed. You can do a simple test yourself. Set a speed/aperture combo and vary
the ASA and look at what it does to the starbursts from a flashlight at night.
Here is a google translate from the German minolta/sony group about the IS
functions.
This commentator is the group moderator and is usually pretty accurate in his
comments.
To understand the comments: E mount lenses are the new Nex series and later A7
lens mounts. The older A mount is is the minolta mount dating back to the mid
80's and carried forward on Sony's larger DSLR's with pentaprisms. There is an
electronic adapter that allows Amounts to be used on Emounts which has a motor
for moving mecahnical parts of Amount. So I have a Minolta 50mm F1.7 for
example I have been playing with,but I still prefer the Zuiko 50mm f1.8 though.
Dear Members,
certainly is the integrated five-axis image stabilizer of the new Sony ILCE 7M2
(7 Alpha II), the main innovation of this full frame camera, and even the
entire system. I think we can assume that this image stabilizer will hold the
future
in all larger E-mount enclosures too, as in all A-mount enclosures.
ILCE_7M2_5_axis_stabilizer.jpg (148.17KB) Number of downloads: 8
Axis 1: nod - vertical rotatory tilt (pitch / "Y" -Tilt)
Axis 2: Yaw - horizontal rotatory pivoting (yaw / "X" -Tilt)
Axis 3: horizontal translation - parallel shift in the horizontal direction
(Sway / X-Shift)
Axis 4: vertical translation - parallel shift in the vertical direction (Heave
/ Y Shift)
Axis 5: Roles / falter - rotation around the optical axis (roll)
(6 axis: distance change - parallel shift back and forth along the optical axis
(Surge / Z-Shift))
The previous anti shake and SteadyShot in A-mount housings stabilized
only the axes 3 and 4, whereas lens-side image stabilizers axes 1 and 2
stabilize in E-mount lenses.
That Sony ever bring out a chassis-based image stabilizer for E-mount
cameras, so begrßenswert as surprising there are in the E-mount lens
system, a wide range of lenses, which itself via an optical
stabilization (OSS = Optical Steady Shot) have - and from Sigma-A-mount
lenses with lens side stabilization (OS Optical Stabilizer), we know
that not both systems may be active simultaneously, since it can easily
happen otherwise, that the camera But Schütte conclusions not
compensated, but be strengthened. So how the five-axis stabilizer work with
lenses that have an optical stabilization?
Well, unlike Sigma system which operates entirely independent lens and
only the power of the camera needs (and therefore operates only with
cameras with eight contacts), found in Sony's solution to communicate
with the camera instead - with the result that the lens side stabilizer
may also be used by the camera integrated system, if it leads to a
better result.
One must distinguish a number of cases here:
E-mount lenses without OSS
The stabilization for all five axes (1, 2, 3, 4 and 5) is done via the
five-axis image stabilization of the camera.
An exception is made for use with front converters that change the
focal length (such as VCL ECF1 and VCL ECU1 for the SEL-16F28 and
SEL-20F28 and VCL ECF2? And VCL ECU2? For the SEL-28F20). In such cases, the
resulting focal length must be entered on the focal
length of the camera menu (see below), and the stabilization reduces to
the axes 1, 2 and 5. FIG.
E-mount lenses with OSS
In the general case of the OSS of the lens takes over the stabilization of the
axes 1 and 2, whereas the axles 3, 4 and 5 can be stabilized on
the camera side through the movable sensor.
However, there are two exceptions:
The OSS lenses SEL-P1650 SEL-1855, SEL and SEL-55210 18200LE not use
their stabilizer, instead, takes over the camera side stabilizer to
stabilize all five axes, as if it was non-OSS lenses. Whether the camera
automatically takes this decision on the basis of
data stored in the lens or whether it is a hard-wired (and, if
necessary, only through firmware updates extensible) are exceptions list with
these lenses in the camera's firmware is not yet known.
Sony itself, there is no front Converter for OSS lenses, but should
such lenses with focal length changing front converters used by
contractors, the resulting focal length must be entered using the
camera's menu, and the overall system then stabilizes only the axes 1, 2 and .
5
A-mount lenses
As with E-mount lenses without OSS operating at about LA-EA1, EA2
LA-LA-LA-EA3 or EA4 coupled A-mount lenses, the five-axis stabilization
in the camera. The following cases must be distinguished:
If it is a lens with built-in distance encoder (all lenses with eight
contacts are included, provided they are operated directly or eight pole
teleconverter or rings and it is not to xi lenses), all five axes (1, 2 , 3, 4
and 5) stabilized. This is also true for Sigma lenses with OS, but it must be
disabled by
the user - alternatively you can also work with Sigma's OS, but then the camera
side stabilizer must be disabled. In general it can be said that all lenses
with the identifiers ( D), SSM or SAM have eight contacts, but since the Sony
identifier ( D) has not taken there at Sony also quite a number of lenses
without
identifiers that have eight contacts (and distance encoder).
If it is a lens without distance encoder (ie all lenses with five
contacts and all xi lenses and eight-pole lenses using teleconverters,
extension tubes or bellows with five contacts), which has no special
macro mode (or this is not activated) so only the axes 1, 2 and 5 can be
stabilized. Among the published by Sony lenses, there are only five pieces that
do
not have built-in distance encoder feature (SAL-16F28 SAL-20F28
SAL-28F28 SAL-135F28 SAL-500F80) at Minolta and Konica Minolta concerned the
all lenses, which no (D) contributed in the name.
In the event that there is a lens with macro mode is enabled (which it was for
Minolta times six pieces , all lenses with five contacts), the image stabilizer
may nevertheless all five lines (1, 2, 3, 4 and 5 ) stabilize. This is of
course not for those copies of these lenses, the so modified that they also
support in macro mode autofocus - these are then stabilized only in the axes 1,
2 and 5 (and whether
this will succeed well in the macro range, must yet to be tested).
If A-mount lenses with focal length changing front converters used
(Foreign Companies), the resulting focal length must be entered using
the camera's menu, and the overall system stabilizes then in each case
only the axes 1, 2 and 5. FIG.
Electronically adapted foreign lenses
Electronically adapted foreign lenses must distinguish two cases:
Adapters that turn the lens protocol of the foreign lens more or less
completely to the E-mount protocol ( such as Canon EOS lenses: Metabones EF-E
Smart Adapter MB-EF-E-BM1 / 2/3/4,
Metabones Speed Booster MB_SPEF e-BM1 / 2, Deotech Techart Falcon
EOS-NEX / II / III, King Mount Adapter EF-e (α), Viltrox EF Mount
Adapter NEX, commlite Mount Adapter NEX-CM-EF, or eg for Contax G
lenses: Deotech Techart (Golden) Eagle TA GE1A / TA EN1B / TA-GA2 /
TA-GA3) and those who simply an objective of fixed focal length and
without removal set to "simulate" (like many later with chips provided
MF lenses which have been adapted for the A-mount lens, but also as the
Sigma 1.6x AF Multi-Converter MD-MA and MA Ai-Minolta SR and Nikon F
lenses).
In the first case, there is at least the theoretical possibility that
the adapter converts in the existing lens distance information correctly and,
if necessary, even communication with a possibly present in the
lens image stabilizer. From the perspective of a camera lens would then be
adapted in such a indistinguishable from a real E-mount lens; the camera could
therefore also all five lines (1, 2, 3, 4 and 5)
stabilize, if necessary. even with the aid of a lens-side stabilizer
(otherwise this would, if present, is absolutely off as described
above). At the very least, we can assume that these adapters transmit the focal
length of the attached lens properly. This information is already enough to the
camera side to allow stabilization of axes 1, 2 and 5. Which allow the
addressed adapter if necessary. More, we have to find out by tests.
This also works with "rechippten" MF-A-mount lenses for as long as the
chip reflect the focal length of the lens correctly (which was not
always the case in the early stages of such solutions). The Sigma 1.6x Mount
Converter also fall into this category, because they simulate a 50mm lens - a
lens should therefore connected with approximately this focal length be no
problems in this regard are to be expected. Still, it may be more appropriate
in most cases to adapt Minolta SR and Nikon F lenses directly to glassless
E-mount cameras to avoid the
usually undesirable "teleconverter effect". Thus, although you lose autofocus
and the camera-side adjustability of
the diaphragm, but since it is a five-pin adapter that is anyway no
distance information, you lose in terms of image stabilization nothing:
There are so or only the three axes 1, 2 and 5 stabilized.
Corresponds to the transmitted focal length tatsächlchen not the focal
length of the lens, it must be set on the camera side (this is also true in
conjunction with front converters).
Purely mechanically adapted foreign lenses
The effective focal length of the lens (incl. Possibly. Existing converter)
must be set on the camera side. The camera's menu offers here in stages focal
length settings between 8mm and 1000mm on. The camera can then stabilize the
axes 1, 2 and 5.
Many size,
Matthias
________________________________
From: Mike Gordon via olympus <olympus@xxxxxxxxxxxxxxxxx>
To: olympus@xxxxxxxxxxxxxxxxx
Sent: Saturday, November 29, 2014 2:36 PM
Subject: Re: [OM] Sony A7II, IS more info
In the Sony supplied graphic if the lens has OSS the OSS, takes care of
the pitch/yaw stabilization, and the IBIS takes care of the rotational
and X/Y part.
I didn't see anything that implied that 5 Axis IBIS isn't available for
unstabilized lenses though. I hope that German group is incorrect.
Wouldn't make sense if the
IBIS is an up-sized Oly system.
Here is one common example of sensor flare on the A7--prominent on
night shots with the A7:
https://farm6.staticflickr.com/5606/15650158060_7e78bbac62_b.jpg
Note multicolored reflections--these are independent of the lens used.
Early informal testing suggests the sensor stack on the A7II has
changed and this cam may be free of this effect.
Mike
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