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Thread: DX0 ratings . . . Didn't the A55 do well

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    DX0 ratings . . . Didn't the A55 do well


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    Re: DX0 ratings . . . Didn't the A55 do well

    Arrrgh....I always forget DxO is flash. On my iPad.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by TEBnewyork View Post
    Arrrgh....I always forget DxO is flash. On my iPad.
    Summary:
    DxO rates it as the best APS-C sensor (tied with D90), Top 5/6 APS-C sensors are all Sony.

    Cheers,

    N
    A and E mount Too many lenses.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Stop reminding me, I passed it up in favor of the nex-5!


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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by meilicke View Post
    Stop reminding me, I passed it up in favor of the nex-5!

    I wouldn't worry about it. Most of the ratings for those top cameras are very close and probably within the margin of error.

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    Re: DX0 ratings . . . Didn't the A55 do well

    73 seems far less than a rousing endorsement - OTOH -
    Don't put too much credence in this rating.
    I shoot a camera with an 89 rating and one with a 53 and both make very nice pictures.
    Are Leica M9 owners jumping out of the windows because their favorite camera only scored a 69?

    -bob

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Bob View Post
    ..........Are Leica M9 owners jumping out of the windows because their favorite camera only scored a 69?

    -bob
    Ah, but M8/9 owners have worshipped at the church of Leitz, where upon the hands of Oskar Barnack have been laid upon them!
    Cheers, Dave
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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by dhsimmonds View Post
    Ah, but M8/9 owners have worshipped at the church of Leitz, where upon the hands of Oskar Barnack have been laid upon them!
    Every time I think about this it makes me see double.
    -bob

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    Re: DX0 ratings . . . Didn't the A55 do well

    Actually, to be honest, I'm with Bob and Douglas - never took a great deal of stock of the ratings with respect to the real world.

    Comparing the results with M9 results one doesn't really get the impression of a much better sensor

    Still, it feels like good news on a Sony forum - which is why I posted the post.

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    Re: DX0 ratings . . . Didn't the A55 do well

    While I realize that DxO meaurements are not the same as real world results, I think they are better than any review site when it comes to predicting real world signal to noise, dynamic range, and tonal range. What they don't give you is the color fidelity, banding, absolute resolution, aliasing tendency, etc.

    I did carefully controlled RAW file conversion signal/noise testing of all Micro 4/3 bodies against Samsung NX and Sony NEX. My results were basically identical to what DxO produced for those cameras and in marked contrast to what DPReview published, so I trust the DxO numbers.

    The A55 results speak well of that sensor. Especially when the A33-NEX5 comparison suggests that the translucent mirror is associated with a nearly 1/2 stop of light loss.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Amin View Post
    The A55 results speak well of that sensor. Especially when the A33-NEX5 comparison suggests that the translucent mirror is associated with a nearly 1/2 stop of light loss.
    This should auger well for the A580 with optical viewfinder then? Also any further models using developments of this sensor......ie "A780" or equivalent.
    Cheers, Dave
    www.simmondsphotography.com

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    Re: DX0 ratings . . . Didn't the A55 do well

    Both of my cameras scored a 69. I do like them both a lot, but if I thought they were equal, I could just sell the expensive one and put the $$$ in the bank. That is not going to happen because they are not equal IMHO, but I do not usually look at ratings and charts.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Well the big issue with DXO is it does not count for any raw processing software and it is based on raw data before it hits the raw processing which in reality is meaningless. We care what happens after the processing. Too me it is a guide and only a guide
    Photography is all about experimentation and without it you will never learn art.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Guy Mancuso View Post
    Well the big issue with DXO is it does not count for any raw processing software and it is based on raw data before it hits the raw processing which in reality is meaningless. We care what happens after the processing
    Thanks Guy for this explanation!

    I was always wondering why cameras - which deliver really stunning results - are sometimes at such low score levels. This is true for my D700 (was for D3), Sony A900 as well as H3D39 - all significantly better than they should be compared to DXO tests.

    So we see once more that RAW processing is really a key part in the whole chain.

    Question remaining

    1) what sense do DXO tests then make???
    2) and why does DXO not test including (at least) the recommended RAW SW for each camera model ????

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    Re: DX0 ratings . . . Didn't the A55 do well

    1) what sense do DXO tests then make???

    Well it is a guide on a scientific level of what the sensor can produce but I say at least at the minimum of what it can produce since the raw processing can make corrections for noise, DR and such through it's algorithms. So on a sensor level it's not a bad guide just not a real world guide since some raw processing is tuned to specific sensors and cams. Like your Hassy with Phocus for instance. Obviously you know you can get more off the sensor through your software. Part two is related to this

    2) and why does DXO not test including (at least) the recommended RAW SW for each camera model ????

    Simply because there are some cams without dedicated software or lets say tuned to a specific sensor and than also there are just to many variables among all the raw converters so almost impossible to get real scientific fact on it.

    A lot like MTF charts in a way , great numbers but does not count for any look in the images.

    To me these things like MTF charts and DXO are just parts of a big puzzle to evaluate how things will be in final but there is a whole lot of stuff missing in between shooting and final image. One thing I have learned with Phase especially how much the DXO numbers really don't count since the final image is so much better than the raw data in the beginning. Same with other cams and raw processing engines. To me it is the whole chain of events to final IQ and as photographers not scientists we look at our final results to make any real world decisions on how we like things and if it all works.

    The interesting thing is we need the science to actually make and produce sensors, software and such but in the end it is the whole chain of events that makes the final IQ. So yes we NEED the science but we also NEED to forget the science as well as shooters.

    At least this is i view the whole digital world of photography.
    Photography is all about experimentation and without it you will never learn art.

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    Re: DX0 ratings . . . Didn't the A55 do well

    I think the good news for me is that we are getting to a point where APS-C, 35mm and MFDB sensors are all producing pretty outstanding images. Noise handling is nearly to a point where I'm not sure that I need it to improve much more (famous last words,) and DR of sensors is getting large enough that lenses are becoming the limiting factor of the camera DR. I'm not printing much more than 13x19 anymore, so my camera options feel limitless (can't wait to try an X100.) I certainly never thought I'd sell the A900 and start shooting what is essentially an APS-C digital back (NEX-5,) but I'm having fun with it, and I THINK that's the point. lol.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by douglasf13 View Post
    I think the good news for me is that we are getting to a point where APS-C, 35mm and MFDB sensors are all producing pretty outstanding images. Noise handling is nearly to a point where I'm not sure that I need it to improve much more (famous last words,) and DR of sensors is getting large enough that lenses are becoming the limiting factor of the camera DR. I'm not printing much more than 13x19 anymore, so my camera options feel limitless (can't wait to try an X100.) I certainly never thought I'd sell the A900 and start shooting what is essentially an APS-C digital back (NEX-5,) but I'm having fun with it, and I THINK that's the point. lol.
    Agree and the bottom line is your having fun. Major key point to anything shooting wise, if it makes you get out and shoot than all the other stuff is just flat out BS. But i do also agree with you as someone that has been shooting digital for 20 years the gap is closing as the technology gets better no question.

    It's awesome like something like the size of these 4/3rds wonders and NEX cams can be so good these days. Just amazes me


    After just finishing the workshop in Yosemite as most where shooting MF stuff we had a member here that shot a G1 and did a ton of pano stitching on the workshop and his images where amazing.
    Photography is all about experimentation and without it you will never learn art.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by douglasf13 View Post
    Noise handling is nearly to a point where I'm not sure that I need it to improve much more (famous last words,) and DR of sensors is getting large enough that lenses are becoming the limiting factor of the camera DR.

    Douglas, I am not so sure about the lenses becoming the limiting factors (especially for dynamic range). It depends on the lenses you choose to use.

    Specifically, instead of the Cosina 35/1.4, if you would use the Schneider C-Curtagon 35/2.8 (very high resolution lens), you would notice this.

    PS: I don't look at DXO site for anything.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Has anybody noticed what the lowly APS-C Pentax K-5 just got on DxO? Not 73. A hint: it starts with an 8 and ends with a 2!

    For example Nikon D3 gets 81.

    EDIT:

    DxOMark Sensor Scores
    Overall Score 82
    Portrait (Color depth) 23.7 bits
    Landscape (Dynamic range) 14.1 Evs!
    Sports (Low-Light ISO) 1162 ISO
    EDIT 2: Sorry to sidetrack this Sony related thread but I think it gives some idea where the APS-C IQ is today according to DxO.
    Last edited by emr; 5th November 2010 at 08:37.

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    Re: DX0 ratings . . . Didn't the A55 do well

    I actually sold the c-Curtagon 35/2.8 a few weeks ago. I'm really enjoying the Contax G 35/2 right now. I must have a good copy.

    Regardless, that isn't the point. Iliah Borg can get into the specifics, as he is about the best out there in regards to testing (he co-developed RPP and libraw,)but even the very best primes with simple element designs aren't able to pass more than 11-12 stops of DR, due to internal reflections. There was a really long, cool video lecture that I watched a couple of years ago from Kodak in regards to internal lens reflections, but I don't remember the source.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by emr View Post
    Has anybody noticed what the lowly APS-C Pentax K-5 just got on DxO? Not 73. A hint: it starts with an 8 and ends with a 2!

    For example Nikon D3 gets 81.

    EDIT:



    EDIT 2: Sorry to sidetrack this Sony related thread but I think it gives some idea where the APS-C IQ is today according to DxO.

    Well, as I understand it the K5 has the same Sony sensor that's in the A55. . . . but it doesn't look like it from this!
    the K5 is 8 points better than any other ApsC camera - after which, there are 10 cameras within 5 points of each other.

    I must say, if the K5 had been there instead of the K7 when I tried out Pentax for a week, then there might have been a different outcome.

    It looks like a splendid camera.

    all the best
    Last edited by jonoslack; 5th November 2010 at 09:08.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Are there lens adapters that allow use of other lenses on a K-5? Probably need to wait for the electronics to appear in the NX series?

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    Re: DX0 ratings . . . Didn't the A55 do well

    Guy, Doug, all,

    indeed the quality of todays sensors is really stunning. I always thought in DSLR I need to go FF because of pixel size and resulting better dynamic range etc. compared to 43 and APSC size sensors. But both, my EP2 and my NEX5 show me every day, what IQ I can get out of those tiny marvels. Even with the not so optimal lenses for these cams.

    Now if we go MFD and we are talking about larger sensor sizes (at least the size of the S2), I must say that the difference between a FF DSLR or a recent incarnation of a M43 (GH2) or NEX or A55/33 is no longer as big as it was some years ago. Not talking about number of pixels of corse, but rather about dŽDR and high ISO low noise etc. Still MFD has its differences, but they are getting much smaller.

    Kind of where i am today with my "old" H3D39 and the latest incarnations of Nikon D700 or D7000 and if I extrapolate to an upcoming D4X or Sony A900 successor which will have around 30-35MP and for sure better dynamic range and high ISO performance than their contemporary counterparts, then I think the difference to a S2 or P40+ or H4D40 and even higher resolution MF cams will vanish quickly. That is the only reason I am currently holding off to change my H3D39 to a S2 or a H4D40 or H4D60. Because for that money I can get so much Nikon gear - man you cannot even name it - and I know I do NOT need it

    The only thing I see really above today's state of the art MFDBs is a high res DB with a tech cam. The way that Terry went with her P40+ or many others here in this forum. If you really want highest IQ then this is the way to go! Everything else starts kind of growing into a single cloud (or at least some very close clouds).

    Well - happy to have what I have and changes will be there in the future - maybe from Hassi to Leica (S) or even to a tech cam with a P65+ as soon as these beasts get cheaper when the P85+ (or however it will be called) hits the market

    Times are actually very interesting!

    And this forum is really the BEST PLACE to be in order to understand all these changes.

    Thanks

    Peter

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by jonoslack View Post

    Well, as I understand it the K5 has the same Sony sensor that's in the A55. . . . but it doesn't look like it from this!
    the K5 is 8 points better than any other ApsC camera - after which, there are 10 cameras within 5 points of each other.

    I must say, if the K5 had been there instead of the K7 when I tried out Pentax for a week, then there might have been a different outcome.

    It looks like a splendid camera.

    all the best
    Remember the SLT mirror that takes out some light. A580 will have similar ratings.

    Cheers,

    N
    A and E mount Too many lenses.

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    meilicke
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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by clark666 View Post
    Are there lens adapters that allow use of other lenses on a K-5? Probably need to wait for the electronics to appear in the NX series?
    I am not sure I understand your second question. The Samsung NX and Pentax K5 are different beasts, different lens mounts.

    To answer the first question, All K mount lenses will work on the K5, within their various limitations (AF, A, M, etc.). You can also get an m42 adapter. I have a pentax brand K to m42 which works fine.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by BackToSlr View Post
    Remember the SLT mirror that takes out some light. A580 will have similar ratings.

    Cheers,

    N
    Of course - silly me.
    I saw a 580 in a store today - looked like a nice camera (no time to play)

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by douglasf13 View Post
    but even the very best primes with simple element designs aren't able to pass more than 11-12 stops of DR, due to internal reflections. There was a really long, cool video lecture that I watched a couple of years ago from Kodak in regards to internal lens reflections, but I don't remember the source.



    Internal reflections would affect the contrast of an image (ie., lower it) how would they decrease the dynamic range? Higher the DR, flatter the image, no?

    Aside from this, if there is light loss due to the pellicle mirror in A55, as long as the loss is uniform, I do not see why it would affect the DR.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Oddly enough, I was just talking about this with someone on another forum, Vivek:
    http://www.fredmiranda.com/forum/topic/952569/0#9008731

    However, the mistake I made is assuming that the DxO DR measurement was related to the more common idea of dynamic range in a scene. Rather, it is "based off of a SNR of 0dB in the shadows - that is noise and shadow power is equal." -kwalsh

    Shoot, so much for the posts about having fun around here!
    Last edited by douglasf13; 5th November 2010 at 13:15.

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    Re: DX0 ratings . . . Didn't the A55 do well

    While some people haven't taken (or still don't) Sony's photography business seriously, I think they're currently on the bloody bleeding edge. The NEXes are amazingly small for an APS-C sensor, the A55/33 are great game changers. And if cameras like Pentax K-5 and Nikon D7000 give good results, what's partly behind that - a Sony sensor! I'm a Pentax shooter myself, but I'm seriously considering getting a Sony too, probably the A55. But then again, the DxOMark score for the K-5 makes my reconsider...

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by emr View Post
    While some people haven't taken (or still don't) Sony's photography business seriously, I think they're currently on the bloody bleeding edge. The NEXes are amazingly small for an APS-C sensor, the A55/33 are great game changers. And if cameras like Pentax K-5 and Nikon D7000 give good results, what's partly behind that - a Sony sensor! I'm a Pentax shooter myself, but I'm seriously considering getting a Sony too, probably the A55. But then again, the DxOMark score for the K-5 makes my reconsider...
    I would get the camera that makes you happy. DxO Mark ratings are showing nuances that most would probably not notice in practice. Just about any more recent APS-C sensor will be fine.

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    Re: DX0 ratings . . . Didn't the A55 do well

    The DxO silliness really ought to stop.
    Please produce comparison images from two cameras and show us the practical manifestations of the scores?

    Anyone????


    -bob (feeling grumpy)

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    Re: DX0 ratings . . . Didn't the A55 do well

    I am with you, Bob!

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Bob View Post
    The DxO silliness really ought to stop.
    Please produce comparison images from two cameras and show us the practical manifestations of the scores?

    Anyone????


    -bob (feeling grumpy)
    Bob, here's an example. At very high ISO, the NEX5 has a stop or more advantage over the G2/GF1/E-PL1/E-P2 (all featuring the same sensor). You can see that by looking at these side-by-side crops (RAW conversions with color noise removed):



    This was a predictable result based on the DxO data:



    If you look at the rest of my comparison images here and compare them to the DxO results, they correlate very well. You can download my RAW files from that page, process them in your RAW processing app of choice, and I think you'll find that the DxO results still hold up.

    DxO can be misleading though. For example, if you download my RAW files, you'll see some ugly banding in the GH1 files, which has a real effect on image quality. This is completely ignored by DxO, as are several other parameters of image quality including lens performance, JPEG engine, NR applied at the RAW level, susceptibility to aliasing, color fidelity, etc.
    Last edited by Amin; 5th November 2010 at 14:43.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by emr View Post
    While some people haven't taken (or still don't) Sony's photography business seriously, I think they're currently on the bloody bleeding edge. The NEXes are amazingly small for an APS-C sensor, the A55/33 are great game changers. And if cameras like Pentax K-5 and Nikon D7000 give good results, what's partly behind that - a Sony sensor! I'm a Pentax shooter myself, but I'm seriously considering getting a Sony too, probably the A55. But then again, the DxOMark score for the K-5 makes my reconsider...
    I think it's an interesting point - I shoot Sony (A900 and A55), although I was lured into a week testing a K7 in July (tempted by size, water resistance, build, limited primes). I loved the camera and the lenses . . . and wasn't convinced by the sensor (or the results of the sensor). If the K5 had been available then I'm sure I'd still have it.

    On the other hand, there is nothing in the Pentax range to compete with the A900 (even now), and the A55 didn't exist in July (and you can hose two A55 bodies for the cost of a K5!)

    I'm going to wait with interest to see what Sony do at the top end next year, if it isn't convincing then I'll be thinking of Pentax again.

    But the obvious lead that Nikon and Canon had a couple of years ago certainly seems to be under attack right now.

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Amin View Post
    Bob, here's an example. At very high ISO, the NEX5 has a stop or more advantage over the G2/GF1/E-PL1/E-P2 (all featuring the same sensor). You can see that by looking at these side-by-side crops (RAW conversions with color noise removed):



    This was a predictable result based on the DxO data:



    If you look at the rest of my comparison images here and compare them to the DxO results, they correlate very well. You can download my RAW files from that page, process them in your RAW processing app of choice, and I think you'll find that the DxO results still hold up.

    DxO can be misleading though. For example, if you download my RAW files, you'll see some ugly banding in the GH1 files, which has a real effect on image quality. This is completely ignored by DxO, as are several other parameters of image quality including lens performance, JPEG engine, NR applied at the RAW level, susceptibility to aliasing, color fidelity, etc.
    Amin,
    I think the last point you make is the real point combined with the raw processing that one performs to the image.
    <rant annoyance="high">
    Here is another characteristic: the pattern of the noise.
    Many times noise appears is bands or clumps or some other pattern that makes it more obvious than s/n measurements. Just to set the record straight, I am an engineer through and through and eat measurements for breakfast. I just happen to think that the DxO measurements are not only inadequate but misleading.
    Even many raw files have been in-camera processed to one degree or another so it is not so much sensor but the total image chain.
    I have to confess that for me, ISO 50 is here I usually shoot and consider iso 800 to be sort of the outer limits. If you want to really understand the performance of a sensor then it ought to be done at the base sensitivity of the sensor itself. Reading actual sensor data sheets is often instructive, since many of them, or almost all of them actually, have only ONE sensitivity, with the higher sensitivities synthesized by shifting the data and reducing the actual number of information containing bits. Sometimes zeros are forced into the low order bits, sometimes whatever stuff happens to be produced by the a/d converter. In any case the number of luminance levels (bits of significant data) is reduced resulting in banding or other visual manifestations dependent on the scene.
    Mostly the what the DxO numbers OUGHT to be can be derived from sensor data sheet values. Where they differ is a result of firmware, post sensor processing chain, and measurement artifacts. The true test is in the taking. If you start with a iso100 base sensitivity 14 bit (really hard to do well) sample and create an ISO 3200 file, it is not going to have more than about 9 bits of data with the low order bit of those nine just as noisy as the 14th bit of the base ISO sample.

    Another annoying bit...
    There is no such thing as color noise.
    So far bayer image arrays all produce monochrome sample data filtered to red green and blue (admittedly with different band pass depending on sensor model). usually there is twice the number of green pixels than red or blue. There is thus one more potential bit of data available for luminance information, but not on every pixel, on the collection of near neighbors that are included in the debayering algorithm. This difference is sometimes processed as "color" noise which is more an artifact of the image processing algorithm.
    So give me a break, show me the images and the ways that they differ for use by YOU in the ways that you care about.

    The imposition of a pseudo-scientific measurement methodology for the comparison of sensors does more to obfuscate than to enlighten IMO.

    and finally, their characterization of qualities such as color depth as relating to use in portraiture and dynamic range a landscape is downright idiotic. When I shoot a model, I want good depth and texture in the darks of brown irises and the specular highlights of glossy skin and when I shoot a landscape us old timers have been dealing with techniques to control image dynamic range from the zone system through multiple exposures at different EVs and selective layering but we still want all the color nuance we can get.</rant>
    -bob

  36. #36
    Administrator Bob's Avatar
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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Bob View Post
    Amin,
    I think the last point you make is the real point combined with the raw processing that one performs to the image.
    <rant annoyance="high">
    Here is another characteristic: the pattern of the noise.
    Many times noise appears is bands or clumps or some other pattern that makes it more obvious than s/n measurements. Just to set the record straight, I am an engineer through and through and eat measurements for breakfast. I just happen to think that the DxO measurements are not only inadequate but misleading.
    Even many raw files have been in-camera processed to one degree or another so it is not so much sensor but the total image chain.
    I have to confess that for me, ISO 50 is here I usually shoot and consider iso 800 to be sort of the outer limits. If you want to really understand the performance of a sensor then it ought to be done at the base sensitivity of the sensor itself. Reading actual sensor data sheets is often instructive, since many of them, or almost all of them actually, have only ONE sensitivity, with the higher sensitivities synthesized by shifting the data and reducing the actual number of information containing bits. Sometimes zeros are forced into the low order bits, sometimes whatever stuff happens to be produced by the a/d converter. In any case the number of luminance levels (bits of significant data) is reduced resulting in banding or other visual manifestations dependent on the scene.
    Mostly the what the DxO numbers OUGHT to be can be derived from sensor data sheet values. Where they differ is a result of firmware, post sensor processing chain, and measurement artifacts. The true test is in the taking. If you start with a iso100 base sensitivity 14 bit (really hard to do well) sample and create an ISO 3200 file, it is not going to have more than about 9 bits of data with the low order bit of those nine just as noisy as the 14th bit of the base ISO sample.

    Another annoying bit...
    There is no such thing as color noise.
    So far bayer image arrays all produce monochrome sample data filtered to red green and blue (admittedly with different band pass depending on sensor model). usually there is twice the number of green pixels than red or blue. There is thus one more potential bit of data available for luminance information, but not on every pixel, on the collection of near neighbors that are included in the debayering algorithm. This difference is sometimes processed as "color" noise which is more an artifact of the image processing algorithm.
    So give me a break, show me the images and the ways that they differ for use by YOU in the ways that you care about.

    The imposition of a pseudo-scientific measurement methodology for the comparison of sensors does more to obfuscate than to enlighten IMO.

    and finally, their characterization of qualities such as color depth as relating to use in portraiture and dynamic range a landscape is downright idiotic. When I shoot a model, I want good depth and texture in the darks of brown irises and the specular highlights of glossy skin and when I shoot a landscape us old timers have been dealing with techniques to control image dynamic range from the zone system through multiple exposures at different EVs and selective layering but we still want all the color nuance we can get.</rant>
    -bob
    and I neglected to mention the effects of temperature, illuminant spectral content, and exposure time
    Forgive me for the over-simplification LOL
    -bob

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Bob View Post
    The imposition of a pseudo-scientific measurement methodology for the comparison of sensors does more to obfuscate than to enlighten IMO.
    Well - I understand nothing about sensors and electronics, but I am a scientist, and this is something I can REALLY relate to.

    . . . . and it seems to me to be almost universal - just try the field of Health and Biology (where I do understand a little) :sleep006:

    Just this guy you know

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    Senior Member Amin's Avatar
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    Re: DX0 ratings . . . Didn't the A55 do well

    We can all agree that the DxOmark data has limitations and can be misleading. We disagree about whether it has some value, but I won't by arguing further.

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    Re: DX0 ratings . . . Didn't the A55 do well

    It has lots of value giving misleading information to make endless threads. Some fora actually specialize in that, I suspect.

    Bob,

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    Re: DX0 ratings . . . Didn't the A55 do well

    Yes, but here we have a little crossed swords and pass on . . . or so it seems!
    It's refreshing after the punch ups this sort of discussion can cause elsewhere.

    Just this guy you know

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by Amin View Post
    We can all agree that the DxOmark data has limitations and can be misleading. We disagree about whether it has some value, but I won't by arguing further.
    Amin,
    I found your picture comparison to be much more illuminating
    peace
    -bob

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    Re: DX0 ratings . . . Didn't the A55 do well

    Thanks, Bob .

  43. #43
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    Re: DX0 ratings . . . Didn't the A55 do well

    Well I have had my views change a couple of times about how useful are the DxoMark results. I have gone from being a firm believer to not believing at all to believing them somewhat again. However I definitely owe this to DxoMark that it made me question the supposedly great improvements in APS-C sensors in terms of high-iso performance.

    DxoMark suggests similar high-ISO SNR performance for most good APS-C sensors from last 4-5 years (before D7000 and K5). Whereas typical belief is that APS-C sensors have improved by one or two stops in last few years. To test that out I downloaded raw files from Imaging-Resource for bunch of APS-C sensors from past few years and passed them through Lightroom 3.2 with noise reduction and sharpening turned to 0. And as far as I could see I didn't notice any real improvement over the years. For example here is a comparison @ iso 1600 between 30D and the supposed high-iso champion NEX5. Here I have upscaled 30D to 14MP to match NEX5 and then took 100% crops. Despite being upscaled, the old 30D seems to be atleast as good if not better than the NEX5:

    NEX5:


    30D:


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    Re: DX0 ratings . . . Didn't the A55 do well

    This shows once again what to think about DXO tests. Actually I could not care less about that .....

  45. #45
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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by ptomsu View Post
    This shows once again what to think about DXO tests. Actually I could not care less about that .....
    If you replied to my post then I don't really understand your comment

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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by curious80 View Post
    If you replied to my post then I don't really understand your comment
    Was not meant as reply to your post, but as my general statement what I think about DXO tests

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    Re: DX0 ratings . . . Didn't the A55 do well

    The 30D test above is a bit misleading for several reasons. Merely setting LR to 0 for NR etc, does not mean that you are getting no NR. Canon is known to do some in camera NR even in RAW processing. Look closely at the 30D image and you can see the soft smearing of fine detail to reduce noise. It is especially visible in the label on the thread and the lower pink fabric with the splatter pattern.
    V/r John

  48. #48
    curious80
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    Re: DX0 ratings . . . Didn't the A55 do well

    I would argue that 30D actually has more detail in at least some parts of the image. For example with the fabric with read leaves, the details in NEX image have been smeared due to noise whereas 30D manages to preserve more detail. You also have to keep in mind that 30D has significantly less resolution - it has only 8MP whereas NEX has almost twice the pixels at 14MP. 30D image in this example had been significantly upscaled which is one cause of the softness. And it is amazing that despite that extreme upsizing it can deliver better detail than NEX for some parts of the image.

    Anyways my point was not to prove that 30D sensor was superior to NEX. It would be a very broad generalization to make based on just a single crop from a single image. Plus despite these being studio images with consistent exposure and lighting etc they are not identical images - for example I think the plane of focus is slightly different in both images which obviously impacts details and so on. The main point was just to argue that these two sensors seem to be roughly in the same league instead of the general belief that the newer aps-c sensors have one or two stops high-iso advantage over old sensors. DxoMark correctly predicts this which is why I find DxoMark as a useful resource even though I don't agree to everything which they say.

  49. #49
    Andrea Buso
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    Re: DX0 ratings . . . Didn't the A55 do well

    Quote Originally Posted by curious80 View Post
    I would argue that 30D actually has more detail in at least some parts of the image. For example with the fabric with read leaves, the details in NEX image have been smeared due to noise whereas 30D manages to preserve more detail. You also have to keep in mind that 30D has significantly less resolution - it has only 8MP whereas NEX has almost twice the pixels at 14MP. 30D image in this example had been significantly upscaled which is one cause of the softness. And it is amazing that despite that extreme upsizing it can deliver better detail than NEX for some parts of the image.
    It may also have something to do with the lenses used on the respective cameras.

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