Olympus OM-D E-M5 II Titanium Edition - Printable Version
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Olympus OM-D E-M5 II Titanium Edition - Klaus - 05-12-2015
This will be our next test body for MFT.
Olympus OM-D E-M5 II Titanium Edition - borisbg - 05-14-2015
It is a beautiful.
Are you saing that MFT will be tested at 50+MP?
Olympus OM-D E-M5 II Titanium Edition - Guest - 05-15-2015
I think he wants a new toy Normally 'test' body upgrades only occur when the sensor resolution increase. The 'trick' by the em5ii doesn't really test lens resolution as it 'fakes' the resolution increase by taking multiple frames and merging them together.
Olympus OM-D E-M5 II Titanium Edition - felix - 05-15-2015
Quote:The 'trick' by the em5ii doesn't really test lens resolution as it 'fakes' the resolution increase by taking multiple frames and merging them together.
Does it? I'm not so sure about that.. If you only shift the sensor and not the lens, the result should be similar to a higher resolving sensor. If the lens does not resolve the additional resolution, what's the point in shifting the sensor (except from more color detail)?
Olympus OM-D E-M5 II Titanium Edition - popo - 05-15-2015
I think the short answer is... it is complicated! I had to look it up as I've not looked at it before in detail. So there are two sets of 4 pixel shifts. Each set of 4 overcomes the biggest flaw of bayer pattern and you get individual RGB sampling at each location.
The second set of 4 is where it gets more complicated. These are diagonally centred between the first 4, so the question then is how much benefit does that give? It wont quite give a complete doubling on X and Y axis, but if you rotate 45 degrees, you could argue it doubles the sampling rate on diagonals.
This is likely further complicated by the usable area of each detection site. We imagine these as being perfect squares, but chances are they're not. We generally like them as big as possible for maximum light collection potential, but this half-shift would result in significant overlaps and you wont get the full benefit. If they were smaller it could help with resolving, at the cost of less sensitivity.
I think we're in a similar situation to when Foveon first came out. Just how do you compare? In reality there probably isn't a single number improvement that represents all situations, but there is some improvement regardless.
Olympus OM-D E-M5 II Titanium Edition - Klaus - 05-16-2015
Interesting point - actually I didn't really think about the potential increase in resolution.
While this could be an interesting exercise, I will stick to 16mp for the mainstream testing.
Olympus OM-D E-M5 II Titanium Edition - Rainer - 05-16-2015
You woudn't have used the "Hi-Rez" option anyway!
There are a few things, that one can easily miss when reading the text:
#1 cite: "special ‘High-Res Shot’ option that is said to deliver resolution equivalent to a 40 Megapixel"
#2 cite: "sensor by combining 8 shots into a single JPEG using sensor shift"
ok ... so ... if an old EOS 300D is said to deliver 100 Megapixel ... we would certainly doubt this information.
but if Oly mentions such a vague phrase, we applaud?
Also ... would you use JPG as a base for MTF measurement?
Just some thoughts ... Rainer
Olympus OM-D E-M5 II Titanium Edition - felix - 05-17-2015
Quote:Also ... would you use JPG as a base for MTF measurement?
If I remember correctly the measurements here at photozone are indeed based on JPGs. Lenstip uses (processed?) RAW-files.
Olympus OM-D E-M5 II Titanium Edition - Rainer - 05-17-2015
Quote:If I remember correctly the measurements here at photozone are indeed based on JPGs. Lenstip uses (processed?) RAW-files.
Of course PZ doesnt feed Raw-files into the Imatest module ... anyhow,
I doubt that OOC Jpgs are used ...
A cite from the Lenstest FAQ:
"There're also evolutions regarding the RAW converter quality so more recent system tests starts can benefit from this - e.g. Canon/Olympus RAWs are/were converted using ACR 3.2 whereas Pentax/Sony RAWs are/were converted via ACR 3.7 and there was an increase in converter quality with ACR 3.4). This must all be taken into account regarding the rating system."
In this context, I doubt that the said-to-be 40Mpix files would have been used ... there is no Rawfile ...
there is only the Jpg OOC.
Olympus OM-D E-M5 II Titanium Edition - Scythels - 05-17-2015
PZ uses software to optimize the sharpening for each lens+sensor combination, then feeds a RAW+sharpening conversion as a TIFF into Imatest, as imatest cannot read raws.
Lenstip converts to raw without any sharpening, and sample images are out of camera JPEGs with sharpening turned off.