G6 vs newest sensors: Real difference in high ISO noize

Started 9 months ago | Questions
Electriq
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G6 vs newest sensors: Real difference in high ISO noize
9 months ago

Hi there! I'm interesting in the real difference in noise at high ISO (3200, 6400) between Panasonic G6 and cameras with the last generation sensors (GX7, GH3, E-M1, etc.).

Most reviewers write that G6 is about 1 stop worse, so G6 ISO 3200 has the same noise as GX7 ISO 6400.

But I mentioned that DXOmark gives about the same 'low-light ISO': G6 639, GX7 718 (only 10% difference). And if we look at '18% SNR' plot, we will see that the measured ISO for latest sensor is significantly lower than specified, so I suppose the real exposure at the same ISO will be longer than with G6 and you need to further increase ISO.

So the question is for those who have used G6 and a camera with the latest sensor: Is the difference significant for you? Both JPEG and RAW answers are interesting.

http://www.dxomark.com/Cameras/Compare/Side-by-side/Panasonic-Lumix-DMC-GX7-versus-Panasonic-LUMIX-DMC-G6-versus-Olympus-OM-D-E-M5___901_875_793

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Grzzl
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

I have a G5, it should be about the same. However, i have worked with quite a lote different camera's and i think the difference in noise is overrated. In real life there is a difference with for example a Nikon D4 (and quite a lot). In the smaller sensor sizes (aps and m43) there is no big difference, imho. I barely notice it when viewing a pic the normal way.

I refuse high iso's (800+) for a different reason. The colors are fading and are sometimes ugly, however there are made big steps in regard this, the last 5 years. The only problem would be sports in bad lightning (high shutterspeed required) which i don't do. I simply use a tripod for my pics.

I am a raw shooter and edit my pic's quite a lot, which induces strong noise. JPEG engines a reducing noise quit well nowadays.

So when you make more static pics most at the time, i wouldn't be bothered by it. If you are a pixel peeper and want the best of the best, then there is maybe a better cam on the market/

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jalywol
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

I had a GH2 (and a G5 for a short while), and currently have an EM1 and a GM1. The GH2 was not very good at high ISO, and, while the G5 was better, it still had less detail, less good color saturation, and more luminance noise than either the EM1 or the GM1 at ISOs over about 800. I assume the G6 is a little better than the G5, but it's still essentially the same sensor with with the same limitations.

I would never shoot above 800 with the G5 and expect to get really excellent results, but with the GM1, I have been very surprised at how good the IQ is at 800 and even 1600 even when examined critically. Things have indeed improved in real world use with the most recent generation of sensors...

Below is a photo of a tulip I took today with the GM1 at ISO 1600. There is just no way I could have expected this kind of detail and color saturation with the G5 sensor at that ISO. The second photo was at ISO 800, and the detail is excellent at that value.

Of course, both of these were taken in daylight, so there will be more noise in very low light situations, but I think you can get an idea of what this newer sensor can do without much work out of camera.

-J

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Ulric
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

Electriq wrote:

So the question is for those who have used G6 and a camera with the latest sensor: Is the difference significant for you? Both JPEG and RAW answers are interesting.

I'm using the DR graph for illustration, because that is the most important difference between the E-M5 and GF3, and the difference is certainly significant. I haven't used a G6, but it seems to be somewhere in between.

BTW, when you look at the "Measured ISO" that DxOmark use, don't assume that it is more real or more correct than the manufacturer stated ISO. It is just defined differently. Look at their measurements within their own coordinate system and you'll be fine.

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Øyvin Eikeland
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Ulric, 9 months ago

Ulric wrote:

BTW, when you look at the "Measured ISO" that DxOmark use, don't assume that it is more real or more correct than the manufacturer stated ISO. It is just defined differently. Look at their measurements within their own coordinate system and you'll be fine.

Hi, I have problems interpreting the DXO graphs. Some help would be appreciated. DXO is apparently calculating the "real" iso sensitivity of the sensor by exposing the sensor to a known intensity and then calculate the sensitivity from the raw files. Is this correct? The points in the graph are then plotted against measured ISO and not against what you set on the camera. The right-most data-point for the OM-D E-M5 is taken with the camera iso set to 25600, right? The measured ISO for this setting is only 11848. Therefore the data point is plotted at 11848 along the X-axis. What I do not get is this: How can I find the dynamic range (or SNR) you will get if I set the camera to an ISO of 25600? If the dynamic range in the raw-files are indeed 6.61EV, isn´t it unfair to plot the point just below 12800?

BR,

Øyvin Eikeland

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Electriq
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Øyvin Eikeland, 9 months ago

I think this kind of plot is useful (if real ISO is measured correctly). Because if you compare two cameras in real conditions, on the same conditions with the same scene lightness, lens f setting and exposure G6 will set ISO 6400 and E-M5 ISO 12800 which corresponds to real 6400. Or alternatively, if we set ISO 6400 on both cameras, the exposure on E-M5 will be 2 times longer. So we have to compare noise and dynamic range of G6 ISO 6400 and E-M5 ISO 12800 to obtain real-life results.

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007peter
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ImageResource comparsion of NEX-6 vs G6 vs GX7. GX7 is stunning @iso3200
In reply to Electriq, 9 months ago

DXO, but the the number - by itself - doesn't mean much without a reference image.  What I do is download Image Resource then compare the result myself.  I can tell you from my own subjective experience having owned many camera that:

DXO LowLight Score of less than 600 are unacceptable to me (GF1, GF2, GF3, older m43 etc...)

I shoot regularly @iso3200, so I need ta minimum dxo low-light of 700 to be somewhat satisfied, and perfectly happen when low-light score near 900.

Here is the side-by-side comparison of G6 (left) vs GX7 (middle) vs NEX-6 (right) @iso3200.  You decide if GX7 is worth it, for me, I think it is.  I'm also shock to see its superior to NEX-6

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texinwien
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Øyvin Eikeland, 9 months ago

Øyvin Eikeland wrote:

Ulric wrote:

BTW, when you look at the "Measured ISO" that DxOmark use, don't assume that it is more real or more correct than the manufacturer stated ISO. It is just defined differently. Look at their measurements within their own coordinate system and you'll be fine.

Hi, I have problems interpreting the DXO graphs. Some help would be appreciated. DXO is apparently calculating the "real" iso sensitivity of the sensor by exposing the sensor to a known intensity and then calculate the sensitivity from the raw files. Is this correct? The points in the graph are then plotted against measured ISO and not against what you set on the camera. The right-most data-point for the OM-D E-M5 is taken with the camera iso set to 25600, right? The measured ISO for this setting is only 11848. Therefore the data point is plotted at 11848 along the X-axis. What I do not get is this: How can I find the dynamic range (or SNR) you will get if I set the camera to an ISO of 25600? If the dynamic range in the raw-files are indeed 6.61EV, isn´t it unfair to plot the point just below 12800?

You need to be careful when looking at the graph and judging the precision distances. Don't forget that the x-axis scales exponentially and not linearly. So, while there are only ISO 100 steps between ISO 100 and ISO200, there are 6,400 ISO steps between ISO 6,400 and ISO 12,800.

Each doubling in ISO is 60 pixels wide on the graph. Between ISO 100 and ISO 200, each pixel will be (roughly, on average) a little less than 2 ISO steps. Between ISO 6,400 and ISO 12,800, each pixel will be (roughly, on average) around 106 ISO steps.

I say 'roughly, on average' because the last pixel between ISO 100 and ISO 200 is more than 2 ISO steps, whereas the first pixel between ISO 100 and ISO 200 is less than 2 ISO steps (again, because the x-axis is scaled exponentially). The same goes for the jump between ISO 6,400 and ISO 12,800 - the last pixels on the right account for more ISO steps than the first pixels on the left.

The formula for determining the exact ISO value at any pixel on the x-axis is 50 * 2^(n/60), where 'n' is the number of pixels from x=50 ISO (the far left of the graph). The center of the furthest right E-M5 dot is 473 pixels to the right of x=50 ISO. Plugging that into our formula, we have:

50 * 2^(473/60) = 11,806 ISO

If anything, the graph is unfair to the E-M5 by 42 ISO steps

BR,

Øyvin Eikeland

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neil holmes
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

Electriq wrote:

Hi there! I'm interesting in the real difference in noise at high ISO (3200, 6400) between Panasonic G6 and cameras with the last generation sensors (GX7, GH3, E-M1, etc.).

Most reviewers write that G6 is about 1 stop worse, so G6 ISO 3200 has the same noise as GX7 ISO 6400.

But I mentioned that DXOmark gives about the same 'low-light ISO': G6 639, GX7 718 (only 10% difference). And if we look at '18% SNR' plot, we will see that the measured ISO for latest sensor is significantly lower than specified, so I suppose the real exposure at the same ISO will be longer than with G6 and you need to further increase ISO.

So the question is for those who have used G6 and a camera with the latest sensor: Is the difference significant for you? Both JPEG and RAW answers are interesting.

http://www.dxomark.com/Cameras/Compare/Side-by-side/Panasonic-Lumix-DMC-GX7-versus-Panasonic-LUMIX-DMC-G6-versus-Olympus-OM-D-E-M5___901_875_793

G6 is actually newer than the E-M5 and GH3.

I had a 12mp EPL2 and was happy to use it at ISO 3200 if I had to, though would rather not...I would think the G6 would be better than the EPL2.

The GX7 is fine at ISO 3200.

Pretty much all cameras these days (and for last few years) are ok at iso 3200 and I would rather make a choice on other things than ISO in m4/3.

http://www.dpreview.com/products/compare/side-by-side?products=oly_em5&products=panasonic_dmcg6&products=panasonic_dmcgx7&products=panasonic_dmcgh3

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texinwien
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

Electriq wrote:

I think this kind of plot is useful (if real ISO is measured correctly). Because if you compare two cameras in real conditions, on the same conditions with the same scene lightness, lens f setting and exposure G6 will set ISO 6400 and E-M5 ISO 12800 which corresponds to real 6400.

That is incorrect. If the G6 sets ISO 6400, the E-M5 will also set ISO 6400 (or something very close to it, assuming all else remains equal).

Or alternatively, if we set ISO 6400 on both cameras, the exposure on E-M5 will be 2 times longer.

That is also incorrect. If we set ISO 6400 on both cameras, the exposures will be roughly equal on both cameras, again, aotbe.

The E-M5 will, in both cases, simply 'underexpose' by almost a full stop from what its sensor would allow, then it will 'brighten' the result (if you're shooting JPEG) or tell your raw editor (some, not all raw editors) how much to 'brighten' the RAW file, per default, when you open it, to make up for the difference.

So we have to compare noise and dynamic range of G6 ISO 6400 and E-M5 ISO 12800 to obtain real-life results.

That is also incorrect.

See this helpful, informative article on Exposure vs. Brightening  for more info...

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arbuz
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to texinwien, 9 months ago

texinwien wrote:

Electriq wrote:

I think this kind of plot is useful (if real ISO is measured correctly). Because if you compare two cameras in real conditions, on the same conditions with the same scene lightness, lens f setting and exposure G6 will set ISO 6400 and E-M5 ISO 12800 which corresponds to real 6400.

That is incorrect. If the G6 sets ISO 6400, the E-M5 will also set ISO 6400 (or something very close to it, assuming all else remains equal).

Or alternatively, if we set ISO 6400 on both cameras, the exposure on E-M5 will be 2 times longer.

That is also incorrect. If we set ISO 6400 on both cameras, the exposures will be roughly equal on both cameras, again, aotbe.

Looking at samples on imaging resource I would say you're incorrect and electriq is right. Do you have anything to support your version or you simply speculate?

Also, if you're right, Oly should have exceptional DR (since by default it loses 1EV by brightening up), however this is not supported by any evidence.

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Electriq
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to texinwien, 9 months ago

texinwien wrote:

That is also incorrect. If we set ISO 6400 on both cameras, the exposures will be roughly equal on both cameras, again, aotbe.

The E-M5 will, in both cases, simply 'underexpose' by almost a full stop from what its sensor would allow, then it will 'brighten' the result (if you're shooting JPEG) or tell your raw editor (some, not all raw editors) how much to 'brighten' the RAW file, per default, when you open it, to make up for the difference.

OK. So supposing that the dynamic range is the same for both cameras/sensors I will expect noise increasing while 'brightening' in the resulting image. And it answer why DXOmark's high-ISO metric is about the same for G6 and E-M5 (639 vs 826, ~25%, not a full stop). Am I right?

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texinwien
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to arbuz, 9 months ago

arbuz wrote:

texinwien wrote:

Electriq wrote:

I think this kind of plot is useful (if real ISO is measured correctly). Because if you compare two cameras in real conditions, on the same conditions with the same scene lightness, lens f setting and exposure G6 will set ISO 6400 and E-M5 ISO 12800 which corresponds to real 6400.

That is incorrect. If the G6 sets ISO 6400, the E-M5 will also set ISO 6400 (or something very close to it, assuming all else remains equal).

Or alternatively, if we set ISO 6400 on both cameras, the exposure on E-M5 will be 2 times longer.

That is also incorrect. If we set ISO 6400 on both cameras, the exposures will be roughly equal on both cameras, again, aotbe.

Looking at samples on imaging resource I would say you're incorrect and electriq is right.

You'd be wrong. Care to share your imaging-resource samples? Before you spend too much time gathering samples, you should know that many of Imaging-Resource's Nikon EXIF exposure numbers are incorrect, so if you're comparing against a Nikon EXIFs from I-R, you're wasting your time. If you have other evidence, I'd be interested in seeing it. I've seen a number of people make the claim you are over the past year and a half, but no one's been able to back it up with evidence, yet...

Do you have anything to support your version or you simply speculate?

Plenty - I've compared a number of EXIFs from studio shots taken by a number of professional review sites. I've also talked with people who've performed their own comparison tests, and I have performed my own comparison tests - in absolutely no case of which I am aware did the evidence point to anything other than the conclusion I have stated here. Then there's this, from DPReview:

By our tests, the E-M5's measured sensitivities are about 1/3 stop lower than indicated across the ISO range.

DPReview claims the metering is about 1/3 stop off (as opposed to a full stop, which Electriq is claiming, and which you seem to be agreeing with).

I'm not aware of anyone else who has confirmed that the metering is off by 1/3 stop, as DPReview claims, and I am aware of a few who have tested and found that there is no discrepancy in the metering (don't have a link handy, but Anders W performed some of the tests and shared the results here).

Also, if you're right,

I am right.

Oly should have exceptional DR (since by default it loses 1EV by brightening up), however this is not supported by any evidence.

This final statement of yours is far too imprecise to warrant a reply.

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Ulric
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to arbuz, 9 months ago

arbuz wrote:

texinwien wrote:

Electriq wrote:

I think this kind of plot is useful (if real ISO is measured correctly). Because if you compare two cameras in real conditions, on the same conditions with the same scene lightness, lens f setting and exposure G6 will set ISO 6400 and E-M5 ISO 12800 which corresponds to real 6400.

That is incorrect. If the G6 sets ISO 6400, the E-M5 will also set ISO 6400 (or something very close to it, assuming all else remains equal).

Or alternatively, if we set ISO 6400 on both cameras, the exposure on E-M5 will be 2 times longer.

That is also incorrect. If we set ISO 6400 on both cameras, the exposures will be roughly equal on both cameras, again, aotbe.

Looking at samples on imaging resource I would say you're incorrect and electriq is right. Do you have anything to support your version or you simply speculate?

I would be surprised to find even a single sample on Imaging Resource where same lighting, same ISO setting and same aperture results in anything close to a 2x difference in shutter speed. You can see for yourself here:

http://www.imaging-resource.com/IMCOMP/COMPS01.HTM

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rolleiman
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Electriq, 9 months ago

I seriously considered the G6; even now I have the odd pang of regret that I didn't get one. But a quick look at IR's New Indoor shots reminds me. Try the Nex 6 or other Sony 16mp sensored cam at 3200 and 6400 vs. the G6. You don't have to blow them up...

The processor in the G6 is pretty amazing but for indoor work it just doesn't have enough to work with above 1600 ISO. Since I shoot a lot at 3200 and 6400 indoors it matters to me. Sure, I don't have any actual shooting time on the camera, but if that's what IR could get out of it above 1600 indoors then I'm not expecting anything different.

I think there is quite a difference between shooting high ISO in good outdoor light for action versus using longer exposures indoors in incandescent or other weak and warm lighting.

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Øyvin Eikeland
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to texinwien, 9 months ago

texinwien wrote:

The formula for determining the exact ISO value at any pixel on the x-axis is 50 * 2^(n/60), where 'n' is the number of pixels from x=50 ISO (the far left of the graph). The center of the furthest right E-M5 dot is 473 pixels to the right of x=50 ISO. Plugging that into our formula, we have:

50 * 2^(473/60) = 11,806 ISO

If anything, the graph is unfair to the E-M5 by 42 ISO steps

BR,

Øyvin Eikeland

Hi,

I am not too concerned about the graphical presentation of the data. If you hover your mouse over the samples the actual measurements are shown. For example:

G6:

Measured ISO: 12663

Manufacturer ISO: 12800

Dynamic range: 5.59Ev

OM-D E-M5:

Measured ISO: 5953

Manufacturer ISO: 12800

Dynamic range: 7.5Ev

I have learned(from this forum) that when both cameras are set at ISO12800 the resulting shutter speed and aperture can be the same for both cameras. The difference in measured iso comes from the fact that olympus deliberately under-exposes the sensor and apply gain digitally in post processing. If I (for some reason) need to shoot at ISO12800 I should compare the two measurement points listed above. It would not be correct to compare them directly I think. That would imply a 2-stop advantage to the OM-D E-M5. How do I calculate the correct dynamic range when both cameras are set at ISO 12800?

BR,

ØE

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texinwien
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Øyvin Eikeland, 9 months ago

Øyvin Eikeland wrote:

texinwien wrote:

The formula for determining the exact ISO value at any pixel on the x-axis is 50 * 2^(n/60), where 'n' is the number of pixels from x=50 ISO (the far left of the graph). The center of the furthest right E-M5 dot is 473 pixels to the right of x=50 ISO. Plugging that into our formula, we have:

50 * 2^(473/60) = 11,806 ISO

If anything, the graph is unfair to the E-M5 by 42 ISO steps

BR,

Øyvin Eikeland

Hi,

I am not too concerned about the graphical presentation of the data.

Ok, you wrote:

The measured ISO for this setting is only 11848. Therefore the data point is plotted at 11848 along the X-axis. What I do not get is this: How can I find the dynamic range (or SNR) you will get if I set the camera to an ISO of 25600? If the dynamic range in the raw-files are indeed 6.61EV, isn´t it unfair to plot the point just below 12800?

It appeared to me that you were asking about the graphic representation (in addition to asking about finding the DR or SNR 18% at camera ISO 25,600.

I'm not sure what your source of confusion is here, or why you consider the graph to be 'unfair' since DxO clearly labels the x-axis "Measured ISO".

If you hover your mouse over the samples the actual measurements are shown. For example:

G6:

Measured ISO: 12663

Manufacturer ISO: 12800

Dynamic range: 5.59Ev

OM-D E-M5:

Measured ISO: 5953

Manufacturer ISO: 12800

Dynamic range: 7.5Ev

I have learned(from this forum) that when both cameras are set at ISO12800 the resulting shutter speed and aperture can be the same for both cameras. The difference in measured iso comes from the fact that olympus deliberately under-exposes the sensor and apply gain digitally in post processing. If I (for some reason) need to shoot at ISO12800 I should compare the two measurement points listed above. It would not be correct to compare them directly I think. That would imply a 2-stop advantage to the OM-D E-M5. How do I calculate the correct dynamic range when both cameras are set at ISO 12800?

Compare the DR at the matching manufacturer ISOs. Since the DxO graphs are plotted using the measured ISOs (and clearly labeled as such), you'll need to determine (by rolling over the graphed points for each camera) which points correspond to the manufacturer ISO for which you wish to compare DR for each camera.

Addendum: and keep in mind that the DR / SNR numbers are calculated based on optimum exposure (to the right), and not based on exposing to the camera's meter. If you expose to the camera's meter with the E-M5, you'll underexpose by about a stop, and the resulting DR will be lower than the maximum possible DR had you exposed optimally to the right.

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Øyvin Eikeland
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to texinwien, 9 months ago

texinwien wrote:

Addendum: and keep in mind that the DR / SNR numbers are calculated based on optimum exposure (to the right), and not based on exposing to the camera's meter. If you expose to the camera's meter with the E-M5, you'll underexpose by about a stop, and the resulting DR will be lower than the maximum possible DR had you exposed optimally to the right.

Ok,

please disregard the "unfair" statement. My only agenda is to try to understand how to interpret this. I want to iterate on your last point: "If you expose to the camera's meter with the E-M5, you'll underexpose by about a stop, and the resulting DR will be lower than the maximum possible DR had you exposed optimally to the right." Now we are getting somewhere. Can you tell me how to calculate how much less the DR would be? Take this point for example:

Measured ISO: 5953

Manufacturer ISO: 12800

Dynamic Range: 7.5Ev

thanks,

ØE

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Electriq
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to texinwien, 9 months ago

texinwien wrote:

Addendum: and keep in mind that the DR / SNR numbers are calculated based on optimum exposure (to the right), and not based on exposing to the camera's meter. If you expose to the camera's meter with the E-M5, you'll underexpose by about a stop, and the resulting DR will be lower than the maximum possible DR had you exposed optimally to the right.

Am I right that dynamic range will be lost in RAW post-processing when brightening? If so, why did Olympus do that?

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Anders W
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Re: G6 vs newest sensors: Real difference in high ISO noize
In reply to Øyvin Eikeland, 9 months ago

Øyvin Eikeland wrote:

Ulric wrote:

BTW, when you look at the "Measured ISO" that DxOmark use, don't assume that it is more real or more correct than the manufacturer stated ISO. It is just defined differently. Look at their measurements within their own coordinate system and you'll be fine.

Hi, I have problems interpreting the DXO graphs. Some help would be appreciated. DXO is apparently calculating the "real" iso sensitivity of the sensor by exposing the sensor to a known intensity and then calculate the sensitivity from the raw files. Is this correct?

For each camera ISO, DxO measures how much exposure the sensor can take before you get highlight clipping in RAW. This in turn determines what they call "measured ISO". If the lowest "measured ISO" of one camera is 100 and that of another 200, it means that the first camera can take twice as much exposure (one EV more) before you see any clipping in RAW.

Comparing DR, SNR, etc. at the same "measured ISO", as DxO does, effectively means that cameras are compared at the same exposure and the same level of RAW file saturation (kept constant at the clipping point of the sensor). Other sites (if they know what they are doing) also compare at the same exposure but at different levels of RAW file saturation (if the camera ISOs are differently calibrated with regard to measured ISO).

The points in the graph are then plotted against measured ISO and not against what you set on the camera. The right-most data-point for the OM-D E-M5 is taken with the camera iso set to 25600, right?

Right.

The measured ISO for this setting is only 11848. Therefore the data point is plotted at 11848 along the X-axis. What I do not get is this: How can I find the dynamic range (or SNR) you will get if I set the camera to an ISO of 25600?

If you expose up to the clipping point of the RAW file, the DR of the image would be the value indicated in the graph (6.61 EV). If you expose less than that it would be correspondingly less (one EV less DR for each EV less exposure).

The difference between the E-M5 with a camera ISO of 25600 and a measured ISO of 11848 and another camera, X, with a camera ISO of 25600 and a measured ISO of 25600 is that at the same exposure (and the meter of the two cameras would normally suggest the same exposure) the ADU values in the RAWs of camera X would be slightly more than one EV closer to the clipping point than that of the E-M5.

Consequently, when camera X is at the clipping point of the sensor, the E-M5 is slightly more than one EV below the clipping point. When the E-M5 is at the clipping point, camera X is has slightly more than one EV worth of clipping.

If the dynamic range in the raw-files are indeed 6.61EV, isn´t it unfair to plot the point just below 12800?

No, it isn't unfair. But I am not sure I understand your reasoning here. Why would it be unfair?

BR,

Øyvin Eikeland

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