How to properly compare RX-100 and NEX-6 kit high ISO noise?

Started Apr 29, 2013 | Discussions
Vlad4D
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How to properly compare RX-100 and NEX-6 kit high ISO noise?
Apr 29, 2013

There is common opinion that small sensor is bad for low light. But small sensor also allows to use smaller lens with bigger aperture value.

For example maximum aperture on RX-100 at 10mm (28mm equiv.) is F1.8. NEX-6 with kit lens can do only around F4.0 at 19mm (28mm equiv.). It means RX-100 sensor can gets about 2 stops more light than NEX-6 sensor? Am I right?

This means that when we use dpreview ISO comparison tool (and if we want to compare cameras - not just bodies) we have to compare for example NEX-6 ISO6400 to RX-100 ISO1600 and noise amount will look very similar.

If this is true we coming to conclusion that low light capabilities of tiny RX-100 is not worse than NEX-6 with kit lens (at least on 28mm equiv). Am I right?

Guys, if someone have RX-100 and NEX could you please do simple test:

For both cameras:

  • Set focal length to 28mm equiv. (10mm for RX and 19mm for NEX). 
  • Set maximum open aperture. (1.8 for RX and about 4.0 for NEX)
  • Set identical shutter speed (for example 1/30).
  • Set ISO to auto or adjust it for proper exposure. (same brightness on both cameras)
  • Set noise reduction to Low. 
  • Shoot same test scene.
  • Post images into this thread.
This test will prove a lot !!!

Thank you,

Vladimir

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nevercat
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

Vladimir you might be right about the difference in apperture between these two cameras, but comparing the noise in this way is just a little bit wrong. You can put an other lens on the Nex and you will have a 19mm lens with F2.8 and the figures will be totaly different.

And you should compare the both at say 50mm too, and then compare the Nex with the 50mm 1.8 lens, look what you get then as a result...

I think that these are two totaly different cameras, both very nice, both aimed at a different type of photographing.Comparing these cameras is a little bit useless.

Then there is a lot more then high ISO quality when comparing cameras...

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Vlad4D
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to nevercat, Apr 29, 2013

I completely agree that with F0.95 50mm primes NEX is better in low light. But I know few people who use only kit zoom on NEX and is not going to buy F1.8 primes. Because of that I just want to compare 2 complete packages for around 500 euros each. NEX-3N is actually closer much for RX-100 in size, price and missing VF (and NEX-3N has low light performance identical to NEX-6 in my test)

I think comparing NEX-3N to RX-100 is fare comparison and for many amateurs the only difference is over-hyped sensor size promising much better pictures in bad light. But if it is not always true - other advantages or RX-100 enters into game - it is smaller, has better video quality, more zoom, memory recall...

I just want to make sure I understand this topic right. It seems that smaller sensor does not necessary makes the camera worse low light performer.

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nevercat
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

Vlad4D wrote:

I completely agree that with F0.95 50mm primes NEX is better in low light. But I know few people who use only kit zoom on NEX and is not going to buy F1.8 primes. Because of that I just want to compare 2 complete packages for around 500 euros each. NEX-3N is actually closer much for RX-100 in size, price and missing VF (and NEX-3N has low light performance identical to NEX-6 in my test)

I think comparing NEX-3N to RX-100 is fare comparison and for many amateurs the only difference is over-hyped sensor size promising much better pictures in bad light.

Well that is just one part of it. The larger sensor gives more control over DOF at the same VOF compared to the smaller sensored cameras. The WA lenses will give more FOV then on the smaller sensors. Due to the larger pixel size you will see less lens faults etc.

But if it is not always true - other advantages or RX-100 enters into game - it is smaller, has better video quality, more zoom, memory recall...

Both are very nice cameras with their own strong and weak points. The main advantage of the Nex over the RX-100 is the flexability of the system. You can (as you want) use other lenses and improve the low light quallity. You can use long tele lenses, you can swivel the screen etc.

I just want to make sure I understand this topic right. It seems that smaller sensor does not necessary makes the camera worse low light performer.

Well not totaly. to compare to sensors lower light capability you have to do it with the same apperture. Then you are comparing the sensor low light capabilities. When someone is interested in good low light they probably are interested in higher IQ as a total, also in better light situations. So they will have to invest in the best camera/lens combination they can get to gain their goal. IQ is more the low light, it is more then numbers in a test.

When you compare at the comparometer on this side you will find that the RX100 at ISO 800 will deliver slightly softer pictures then the Nex6 at ISO 3200, maybe some more noise.

In the end the RX100 is not bad at low ISO at all, but the Nex is better.

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twald
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

Summary: The RX100 will beat the NEX cameras with the kit lens in low light.

I did this test a while ago, but not quite as you specified. I think the test you specified would give the same results. I set the lens of both to their widest angle, which gives each the same, 28mm full-frame equivalent, view. I let the cameras meter the scene. they both chose ISO3200, a 1/25s shutter speed, and max aperture. The RX100 gathered more light and made a brighter picture.

The images are all from raw. They are a central crop. They are not resized; viewing 1:1 will give you a 1:1 view of the actual image. The RX100 images will be larger because it is 20megapixels versus the 5N's 16.

NEX-5n as metered

RX100 as metered

I then adjusted the exposure of each picture (I edited the raw in lightroom) to make them equal (well, almost equal). The RX100 has a clear advantage.

NEX-5N, exposure adjusted in post

RX100,  exposure adjusted in post

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danny006
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

At 50mm (NEX-6) you get a F5.6, the RX100 gives a F4, so 1 stop difference. There is a 1 stop difference in noise, in favour for the NEX-6. If you look at these crops (imaging-resource), ISO800 for the RX100 and ISO1600 for the NEX-6, there is almost no difference, not in detail and not in noise.

Keep in mind that the Sigma 70/2.8 macro lens is used with the Nex-6. So the 16-50 will not be as sharp (I assume anyway).

At the wide end you even get 2 stops difference, in favour of the RX100. So this is a crop from the NEX-6 at ISO3200. You can see that the RX100 at ISO800 beats the NEX-6 at ISO3200.

So your statement is correct I think, the RX100 is a better choice than a NEX plus kitlens. And you get a little more reach.

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Vlad4D
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to twald, Apr 29, 2013

Thank you twald!!!

This is exactly the test I was looking for. I expected that RX-100 will be very close to NEX but I did not expect that it will be even better. Your results exceeded my expectations

This of course does not mean than NEX is not awesome anymore, I have NEX-6 with 6 lens and not going to replace it. I just though that cameras with tiny sensor like RX-100 are completely below APS-C cameras, which is not true from today

Also it proves that without deep technical knowledge just by looking on pictures in comparometer it is not possible to judge which camera is better in terms of high ISO noise.

Vlad

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Vlad4D
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to nevercat, Apr 29, 2013

nevercat wrote:

Vlad4D wrote:

I completely agree that with F0.95 50mm primes NEX is better in low light. But I know few peoplewho use only kit zoom on NEX and is not going to buy F1.8 primes. Because of that I just want to compare 2 complete packages for around 500 euros each. NEX-3N is actually closer much for RX-100 in size, price and missing VF (and NEX-3N has low light performance identical to NEX-6 in my test)

I think comparing NEX-3N to RX-100 is fare comparison and for many amateurs the only difference is over-hyped sensor size promising much better pictures in bad light.

Well that is just one part of it. The larger sensor gives more control over DOF at the same VOF compared to the smaller sensored cameras. The WA lenses will give more FOV then on the smaller sensors. Due to the larger pixel size you will see less lens faults etc.

But if it is not always true - other advantages or RX-100 enters into game - it is smaller, has better video quality, more zoom, memory recall...

Both are very nice cameras with their own strong and weak points. The main advantage of the Nex over the RX-100 is the flexability of the system. You can (as you want) use other lenses and improve the low light quallity. You can use long tele lenses, you can swivel the screen etc.

I completely agree with all your words, I only wanted to clarify question about low light capabilities.

I just want to make sure I understand this topic right. It seems that smaller sensor does not necessary makes the camera worse low light performer.

Well not totaly. to compare to sensors lower light capability you have to do it with the same apperture. Then you are comparing the sensor low light capabilities. When someone is interested in good low light they probably are interested in higher IQ as a total, also in better light situations. So they will have to invest in the best camera/lens combination they can get to gain their goal. IQ is more the low light, it is more then numbers in a test.

Sorry I can not agree here

Today most cameras doing good pictures in bright outdoor light. Completely acceptable for normal soccer mom But most of those cameras will fail completely to make at least not very bad picture of active child indoor.So IMHO low light capabilities is most important property of camera (low noise high ISO and reliable and fast autofocus). And even in good light, low noise high ISO would allow to use smaller and cheaper (not bright) telephoto lens and still keep shutter time short enough for sharp images. IMHO low noise high ISO with fast autofocus is all what is important, the rest already good in most cameras.

When you compare at the comparometer on this side you will find that the RX100 at ISO 800 will deliver slightly softer pictures then the Nex6 at ISO 3200, maybe some more noise.

Yes, I see it too.

In the end the RX100 is not bad at low ISO at all, but the Nex is better.

Agree, RX-100 is best compact ever !!

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Vlad4D
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to danny006, Apr 29, 2013

danny006 wrote:

At 50mm (NEX-6) you get a F5.6, the RX100 gives a F4, so 1 stop difference. There is a 1 stop difference in noise, in favour for the NEX-6. If you look at these crops (imaging-resource), ISO800 for the RX100 and ISO1600 for the NEX-6, there is almost no difference, not in detail and not in noise.

Agree - no difference, because it is same picture (from NEX-6) copied twice

But anyway thank you very much for your research, it proves my initial assumption.

It also means that friend of mine who just have bought NEX-3N would be happier with RX-100

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blue_skies
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

Vlad4D wrote:

danny006 wrote:

At 50mm (NEX-6) you get a F5.6, the RX100 gives a F4, so 1 stop difference. There is a 1 stop difference in noise, in favour for the NEX-6. If you look at these crops (imaging-resource), ISO800 for the RX100 and ISO1600 for the NEX-6, there is almost no difference, not in detail and not in noise.

Agree - no difference, because it is same picture (from NEX-6) copied twice

But anyway thank you very much for your research, it proves my initial assumption.

It also means that friend of mine who just have bought NEX-3N would be happier with RX-100

Vlad, under same lighting, both cameras would expose the same way.

If so, the Nex picture 'feels' more impressive, due to the shallower DOF, even with the kit lens.

In your comparison, you also assume that the aperture (wide open) and shutter speed are 'maxed' out (at 1/60th), and that the camera will have to then increase ISO to match exposures.

Sensor sensitivity roughly relates by area, the APS-C is about 2.5x the size of the 1" RX-100 sensor, or the sensor sensitivity compares by root(3)=1.6x. That is about a stop-and-a-half.

This translates in ISO 800 on the RX-100 being roughly equal to ISO 2400 on the Nex.

And you noticed that the aperture drops off faster at tele-zoom for the Nex than for the RX-100, so there is slight aperture advantage for the RX-100 - but this is much less than a full stop, so not a big contributor.

Then, on non-moving objects, you can add in the OSS/OIS controls on both cameras and how they compare, and also add in the prime lenses on the Nex that have a 2-stop advantage over the zoom lenses at certain focal lengths.

What I am trying to say is that a Nex-3N with kit lens still has advantages over the RX-100, except for size and reach. The RX-100 is quite a bit smaller and definitely a very desirable 'pocket-camera'.

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Henry

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Jonn Quest
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to danny006, Apr 29, 2013

So, am I really better off, looking at cost versus IQ versus convenience, having an RX100 versus the NEX-6?  Especially since I don't plan on buying a prime lens, and rarely use a long (55-210 zoom) (on those occassions, I have access to a DSLR with long zoom).

Quite frankly, is the only benefit of the NEX-6, other than the interchangeable lenses, some added controls and the EVF??

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captura
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

Some irrefutable law of physics should allow that the smaller sensored camera, in this case the RX-100, will have more pixel density, therefore much smaller pixels and resulting higher noise.

An illustration of this would be seen in comparing the RX-100 to the (smaller-pixeled) Panasonic LX-7. Relatively high noise in the LX-7 prevents it from being as useful at higher ISO's, and has a lower dynamic range than the RX-100.

For the same reason, an APS-C sensor should outperform an m43, and a FF outperform an APS-C, all things being equal.

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M. Mitchell
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Jonn Quest, Apr 29, 2013

I spent yesterday shooting landscape and flower pictures with my Nex 6 and Rx100. I noticed something about shooting with each camera that is not mentioned in this discussion. Using my Nex6, I had to stop down to f/16 or even f/22 to attain the depth of field that I had at f/4 or f/ 5.6 with my RX100. In landscape photography I prefer a very wide depth of field keeping every thing sharp from closeup to infinity.  This required that I use a slower shutter speed with the Nex6, resulting at times with an unsharp photo. I had no unsharp photos with the higher shutter speeds of the RX100.

The day was slightly windy. Because I could use a faster shutter speed with the RX100, I could only use that camera for the flower pictures.

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Erik Magnuson
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to captura, Apr 29, 2013

captura wrote:

Some irrefutable law of physics should allow that the smaller sensored camera, in this case the RX-100, will have more pixel density, therefore much smaller pixels and resulting higher noise.

Nope, that's not the laws of physics.  Pixel size has little relation to noise - total sensor size and pixel efficiency (q3, fill factor, color filter loss) matters more.  For example, the NEX7 has smaller pixels than the NEX5 and also has lower read noise.  (See http://www.sensorgen.info/)

For the same reason, an APS-C sensor should outperform an m43, and a FF outperform an APS-C, all things being equal.

In the case of the RX-100, all else is not equal.  It has a very efficient sensor.

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Erik

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Mel Snyder
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to twald, Apr 29, 2013

The only thing I see in these two "as metered" images is that the NEX and RX-100 metering systems are very different. The RX-100 is clearly more center-weighted than the NEX, and read deep into the shadowed hallway. And the reciprocity of the two sensors are very different.

Proof: The extreme left wall is overexposed in the RX-100 but properly exposed in the NEX.

The faster maximum aperture on the RX-100 allowed the software designer to develop a totally different exposure algorithm because he KNEW the lens would never change on the RX-100. That knowledge enables totally different tradeoffs.

The designer of the NEX could make no such assumption.

"Reciprocity" - which those of us from the film era knew well - is key to dynamic range in sensors as well as film. The sensitivity of sensors and film is not linear. The NEX "jams" the reciprocity curve on only one factor, because it cannot open to an aperture wider than f3.5. That forces the worst case for the reciprocity of the NEX sensor. The RX-100 faces no such single-factor jam.

This is especially prejudicial because you allowed the cameras to "choose" ISO 3200, which has a horrible dynamic range - anyone who has actually shot much at ISO 3200 understands that it's horrific on subjects with considerable peak-to-trough lighting challenges. Again, you jam the test against the NEX, but favor the RX-100 because it can admit more light.

These tests are absurd on the face of it, anyway. One device is an optimized tiny camera that is best of class. The other is an interchangeable lens mirrorless that is, in the opinion of all but the MFT crowd, best of class. Comparing the NEX and RX-100 is as absurd as if someone with a digital Hasselblad came came onto the forum and said, "let's compare." To which I'd say, "sure, I'll put my RX-100 in my pocket, you put your Hasselblad in yours, and let's go test cameras."

Anyone for actually taking photos instead of optical arm-wrestling?

NEX-6 with 50mm Summicron, f2.8

wald wrote:

Summary: The RX100 will beat the NEX cameras with the kit lens in low light.

I did this test a while ago, but not quite as you specified. I think the test you specified would give the same results. I set the lens of both to their widest angle, which gives each the same, 28mm full-frame equivalent, view. I let the cameras meter the scene. they both chose ISO3200, a 1/25s shutter speed, and max aperture. The RX100 gathered more light and made a brighter picture.

The images are all from raw. They are a central crop. They are not resized; viewing 1:1 will give you a 1:1 view of the actual image. The RX100 images will be larger because it is 20megapixels versus the 5N's 16.

NEX-5n as metered

RX100 as metered

I then adjusted the exposure of each picture (I edited the raw in lightroom) to make them equal (well, almost equal). The RX100 has a clear advantage.

NEX-5N, exposure adjusted in post

RX100,  exposure adjusted in post

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Mel Snyder
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to M. Mitchell, Apr 29, 2013

M. Mitchell wrote:

I spent yesterday shooting landscape and flower pictures with my Nex 6 and Rx100. I noticed something about shooting with each camera that is not mentioned in this discussion. Using my Nex6, I had to stop down to f/16 or even f/22 to attain the depth of field that I had at f/4 or f/ 5.6 with my RX100. In landscape photography I prefer a very wide depth of field keeping every thing sharp from closeup to infinity.  This required that I use a slower shutter speed with the Nex6, resulting at times with an unsharp photo. I had no unsharp photos with the higher shutter speeds of the RX100.

The day was slightly windy. Because I could use a faster shutter speed with the RX100, I could only use that camera for the flower pictures.

Are you surprised? The RX-100 has a 10.4-37.1mm lens. The NEX-6 has a 16-50mm. OF COURSE you have to stop down a longer lens to get the same DOF of a shorter focal length lens.

Let's make the test fair. Take the lens off the RX-100 and put my 11-16mm Tokina on both cameras. Then we can compare apples to apples.

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captura
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Erik Magnuson, Apr 29, 2013

Erik Magnuson wrote:

captura wrote:

Some irrefutable law of physics should allow that the smaller sensored camera, in this case the RX-100, will have more pixel density, therefore much smaller pixels and resulting higher noise.

Nope, that's not the laws of physics.  Pixel size has little relation to noise - total sensor size and pixel efficiency (q3, fill factor, color filter loss) matters more.  For example, the NEX7 has smaller pixels than the NEX5 and also has lower read noise.  (See http://www.sensorgen.info/)

For the same reason, an APS-C sensor should outperform an m43, and a FF outperform an APS-C, all things being equal.

In the case of the RX-100, all else is not equal.  It has a very efficient sensor.

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Erik

I disagree.

- borrowed from clarkvision.com

Digital Cameras: Does Pixel Size Matter?
Part 2: Example Images using Different Pixel Sizes
(Does Sensor Size Matter?)

http://www.clarkvision.com/articles/does.pixel.size.matter2/

"Conclusions

"Current good quality sensors in digital cameras are photon noise limited and that is the best one can do (improving electronics will not improve the noise). This means that the basic performance can be modeled and predicted. The number of photons a digital camera collects in each pixel is directly related to the size (area that converts photons into electrons) of the pixel and the lens feeding light to those pixels. The more photons collected, the better the signal-to-noise ratio in the image, thus the larger pixel sizes using larger lenses do better in this regard. Larger pixel cameras have better signal-to-noise ratios at all levels, but this becomes more obvious especially at low signal levels compared to cameras with smaller sensors which use correspondingly smaller lenses. In the extremes of current digital cameras with small cameras having pixel sizes near 2-microns, and large pixel cameras (currently found in DSLRs), there is a factor of about 12 to 16 in photons collected. That means the large pixel camera performs at ISO 1200 to 1600 with similar noise and dynamic range performance of a small pixel camera operating at ISO 100. If you are a DSLR owner, do you take all your pictures at ISO 1600? If you are a small pixel point and shoot camera user, do you use ISO 400 often? If so, that is like using ISO 6400 on a large pixel DSLR in terms of noise and dynamic range performance! (Such effective ISO's can be achieved with DSLRs by setting the ISO to 3200 and the meter compensation to -1 stop if the camera does not have an ISO 6400.) It is this fundamental difference of pixel size as to why large pixel DSLRs with their larger lenses have such great noise performance, which leads to superb low light and fast action performance. Whether the difference in noise performance is great enough for you to choose a larger sensor with larger lenses, and thus likely a larger and heavier camera, is a decision you must make for yourself."

"The large pixel camera still shows lower noise, because the lens delivers more light."

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Vlad4D
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Mel Snyder, Apr 29, 2013

Mel Snyder wrote:

"Reciprocity" - which those of us from the film era knew well - is key to dynamic range in sensors as well as film. The sensitivity of sensors and film is not linear. The NEX "jams" the reciprocity curve on only one factor, because it cannot open to an aperture wider than f3.5. That forces the worst case for the reciprocity of the NEX sensor. The RX-100 faces no such single-factor jam.

Yes, it forces worse scenario for NEX. But this was one of the points of the test: will the NEX manage to overcome limited aperture problem with a help of bigger sensor? Seems like no - it only managed to be about the same as RX or little worse (on wide end)

This is especially prejudicial because you allowed the cameras to "choose" ISO 3200, which has a horrible dynamic range - anyone who has actually shot much at ISO 3200 understands that it's horrific on subjects with considerable peak-to-trough lighting challenges. Again, you jam the test against the NEX, but favor the RX-100 because it can admit more light.

It is possible that ISO800 on RX-100 is doing internally exactly same signal amplification as ISO3200 on NEX. Similar noise levels partially proves that. So most likely dynamic range should be also similar. It is just my assumption ...

These tests are absurd on the face of it, anyway. One device is an optimized tiny camera that is best of class. The other is an interchangeable lens mirrorless that is, in the opinion of all but the MFT crowd, best of class. Comparing the NEX and RX-100 is as absurd as if someone with a digital Hasselblad came came onto the forum and said, "let's compare." To which I'd say, "sure, I'll put my RX-100 in my pocket, you put your Hasselblad in yours, and let's go test cameras."

I think comparing always makes sense - it helps us to find right tool for our hobby or work.

Anyone for actually taking photos instead of optical arm-wrestling?

This is brand specific and actually camera line specific forum, and of course people discuss technical aspects here. For pure art we have several other forums on dpreview.com. But by some reason they are no so active as for example this one

Nice picture

NEX-6 with 50mm Summicron, f2.8

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Sony Alpha NEX-6 Sony E 18-200mm F3.5-6.3 OSS Sony E 50mm F1.8 OSS Sony E 16-50mm F3.5-5.6 PZ OSS Sony E 35mm F1.8 OSS
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CosmoZooo
Regular MemberPosts: 452
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Vlad4D, Apr 29, 2013

I don't think 28mm eq is a fair comparison if you want to compare kits. Because with NEX-6 I can go to 24mm eq at f3.5 so then it's f3.5 vs f1.8 which is less than 2 stops.

Then the question becomes by how many stops does the APS-C sensor in NEX-6 better then RX100 sensor when it comes to low ISO performance and details.

I am really bad with these calculations but I can point you to an interesting post where I certainly had to admit I was wrong in my understanding on things but I get it better now:

http://www.dpreview.com/forums/post/50559663

Here's one quote from someone who know what they are talking about:

(Per random78)

So on NEX I can use ISO 2600 and f3.2 and still get about the same quality as RX100 at f1.8 and ISO 800. Thats why we can say that effectively in terms of exposure the f1.8 lens on RX100 is similar to f3.2 on NEX. Which is basically what I had said in my original statement. Also keep in mind that this equivalence is based on the assumption that the difference in sensor performance is exactly scaled by sensor size. In reality that is not completely true as some parts of sensor performance are limited by circuit technology and not sensor size. In practice I find that RX100 @ f1.8 gives me slightly better low light capability than NEX @ f3.5

That said though when you start zooming on the RX100 you quickly start losing the advantage of the f1.8 and the NEX-6 kit will quickly start winning. If you consider that the distortion of the wide angle is hardly perfect for portraits, I'd say even comparing kit for kit NEX-6 wins overall, IMO...unless we are talking specifically at their lowest focal lengths at which RX100 has a slight lead.

P.S. RX100 though is till one impressive camera. Sometime I think it would have been enough for me but then I do have the 55-210 and some legacy lenses if you buy NEX-6 and don't take advantage of other lenses - I think RX100 is a better choice overall.

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twald
Contributing MemberPosts: 502Gear list
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Re: How to properly compare RX-100 and NEX-6 kit high ISO noise?
In reply to Mel Snyder, Apr 30, 2013

Mel Snyder wrote:

The only thing I see in these two "as metered" images is that the NEX and RX-100 metering systems are very different. The RX-100 is clearly more center-weighted than the NEX, and read deep into the shadowed hallway. And the reciprocity of the two sensors are very different.

Proof: The extreme left wall is overexposed in the RX-100 but properly exposed in the NEX.

The faster maximum aperture on the RX-100 allowed the software designer to develop a totally different exposure algorithm because he KNEW the lens would never change on the RX-100. That knowledge enables totally different tradeoffs.

The designer of the NEX could make no such assumption.

"Reciprocity" - which those of us from the film era knew well - is key to dynamic range in sensors as well as film. The sensitivity of sensors and film is not linear. The NEX "jams" the reciprocity curve on only one factor, because it cannot open to an aperture wider than f3.5. That forces the worst case for the reciprocity of the NEX sensor. The RX-100 faces no such single-factor jam.

This is especially prejudicial because you allowed the cameras to "choose" ISO 3200, which has a horrible dynamic range - anyone who has actually shot much at ISO 3200 understands that it's horrific on subjects with considerable peak-to-trough lighting challenges. Again, you jam the test against the NEX, but favor the RX-100 because it can admit more light.

These tests are absurd on the face of it, anyway. One device is an optimized tiny camera that is best of class. The other is an interchangeable lens mirrorless that is, in the opinion of all but the MFT crowd, best of class. Comparing the NEX and RX-100 is as absurd as if someone with a digital Hasselblad came came onto the forum and said, "let's compare." To which I'd say, "sure, I'll put my RX-100 in my pocket, you put your Hasselblad in yours, and let's go test cameras."

Anyone for actually taking photos instead of optical arm-wrestling?

NEX-6 with 50mm Summicron, f2.8

Very nice picture! This illustrates the key difference between the two systems. I understand why you feel it is absurd to compare the two systems, however ...

Most people who have a nex do not have a Summicron to attach to it. Your Hasselblad simile doesn't quite make sense because the 5n + kit lens can be had for less than a new rx100. Add to it the fact that they are both very small cameras when compared to almost everything else, and you should see why people compare the two.

On the fact that I "let the camera choose the ISO": there is no other option. Should I have used a lower ISO or higher?

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