LX3 sensor analysis

[Ehrik]

The E-410 is probably like the other Oly 10Mp cameras that the ISO 100
is really more like ISO 125, but meters like ISO 100, so it has a "built-in"
exposure compensation of +0.3. So it may be wise to shoot with EC -0.3
as default when using ISO 100 to compensate.

Just my two oere
Erik from Sweden

 

[John Sheehy]

John,
You underexposing over 6 EV leaving very little for the image. Let's
say G9 RAW DR is 10 (which is too high) then you squeezing the whole
image into 4 EV. How it can work. In addition to reduce the noise the
goal is to keep the image.

Well, I don't believe in single number definitions of DR. IQ factors such as DR

are not well-served by simple single figures. Simple answers are usually false, in one way or another.

Practical definitions of DR need to take image magnification into account, color balance, needed resolution, etc. I am very skeptical of monolithic DR values.

--
John

 

[ejmartin]

John,
You underexposing over 6 EV leaving very little for the image. Let's
say G9 RAW DR is 10 (which is too high) then you squeezing the whole
image into 4 EV. How it can work. In addition to reduce the noise the
goal is to keep the image.

Well, I don't believe in single number definitions of DR. IQ factors
such as DR
are not well-served by simple single figures. Simple answers are
usually false, in one way or another.

Practical definitions of DR need to take image magnification into
account, color balance, needed resolution, etc. I am very skeptical
of monolithic DR values.

--

I would think that the relevant point is that the camera only has about 4EV of DR at ISO 6400 anyway, so you don't lose much of anything by a 6+ stop push of ISO 80 relative to shooting at ISO 6400 with analog gain.

--
emil
--



http://theory.uchicago.edu/~ejm/pix/20d/

 

[win39]

but once i also have made a test with LX1 and LX3 and i think it is
visible from this crop, that the LX1 sensor has considerably stronger
noise, although the LX1 image appears sharper, probably due to a
stronger AA-filter in the LX3, but the captured details seem
nevertheless to be more or less equal.

I don't know for sure about Panasonic, but most small sensor cameras do not use an AA filter. Probably all the difference is in the DA converter.

 

[Leo]

Erik,

Does the higher actual ISO applied only to ISO 100 or to every E-410 ISO setting? Does it mean that for every setting the Native Sensor ISO multiplied by 1.25 and by gain for resulting 200, 400, 800 and 1600 before A/D conversion?
I use camera only RAW setting.
Thanks for the tip.
Leo

 

[Ehrik]

No, only ISO 100. (This assuming dxomark.com's E-520 RAW result applies,
or some of DPR's JPEG tests.)

If so, then only at ISO 100 you need to apply an extra EC -0.3 correction.

The sensor is probably native ISO 125. But I guess they wanted to call it
ISO 100 for the specs or some buyers would find the lack of ISO 100 a
negative (?), but they didn't want to overrate all higher ISOs since it
would make them noisier than needed.

Erik,
Does the higher actual ISO applied only to ISO 100 or to every E-410
ISO setting? Does it mean that for every setting the Native Sensor
ISO multiplied by 1.25 and by gain for resulting 200, 400, 800 and
1600 before A/D conversion?
I use camera only RAW setting.
Thanks for the tip.
Leo

Just my two oere
Erik from Sweden

 

[Ehrik]

You underexposing over 6 EV leaving very little for the image. Let's
say G9 RAW DR is 10 (which is too high) then you squeezing the whole
image into 4 EV. How it can work. In addition to reduce the noise the
goal is to keep the image.

He said web-sized.

If you have 4EV at 4000x3000 and assuming the noise is random and not patterned, then you should have 5EV at 2000x1500, 6EV at 1000x750 and 7EV at 500x375.
Maybe this can be improved on with smart use of NR.

Just my two oere
Erik from Sweden