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Thread: A7s!

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Thank you, but it is not high ISO that I am interested in.
    For base ISO it will be very challenging for the A7s to outperform the A7r. Megapixel/resolving differences aside, it's very difficult to achieve the same level of low ISO dynamic range using large pixels vs small. The D4/D4s/Df are good examples - they are the best performing large-pixel sensors to date yet their base ISO DR is still > 1EV below the A7r/D800.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    For base ISO it will be very challenging for the A7s to outperform the A7r. Megapixel/resolving differences aside, it's very difficult to achieve the same level of low ISO dynamic range using large pixels vs small. The D4/D4s/Df are good examples - they are the best performing large-pixel sensors to date yet their base ISO DR is still > 1EV below the A7r/D800.
    That is what people say but sometimes I like to see things myself so I will still give it a try. Why? Because from where I am at I don't see how 3 smaller pixels that occupy same surface area as one larger pixel can give me extra stop of data with everything else being same.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    That is what people say but sometimes I like to see things myself so I will still give it a try. Why? Because from where I am at I don't see how 3 smaller pixels that occupy same surface area as one larger pixel can give me extra stop of data with everything else being same.
    If you take another peak at the link I provided in the earlier post I also compare low ISO DR between the D800 and Df. The reason larger pixels have less dynamic range is because a larger pixel holds a larger charge (more electrons), and the process of holding and reading out those extra electrons creates extra electronic read noise. Also, with more, smaller pixels (higher MP), more of that electronic read noise can be averaged during the process of downsampling to produce the equivalent MP image as the larger-pixel sensor. This is why for example the 12MP Nikon D3s has a relatively poor base ISO DR of just under 12EV vs 14EV+ on the A7r/D800. With the introduction of the D4 sensor, Nikon improved base ISO DR significantly by using what is purported to to be Aptinas (A-Pix technology, PDF here), which allows two levels of conversion gain, one optimized for low ISO and the other for High ISO, but even with this significant improvement the D4's low ISO DR performance is still 1EV below the A7r/D800.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    If you take another peak at the link I provided in the earlier post I also compare low ISO DR between the D800 and Df. The reason larger pixels have less dynamic range is because a larger pixel holds a larger charge (more electrons), and the process of holding and reading out those extra electrons creates extra electronic read noise. Also, with more, smaller pixels (higher MP), more of that electronic read noise can be averaged during the process of downsampling to produce the equivalent MP image as the larger-pixel sensor. This is why for example the 12MP Nikon D3s has a relatively poor base ISO DR of just under 12EV vs 14EV+ on the A7r/D800. With the introduction of the D4 sensor, Nikon improved base ISO DR significantly by using what is purported to to be Aptinas (A-Pix technology, PDF here), which allows two levels of conversion gain, one optimized for low ISO and the other for High ISO, but even with this significant improvement the D4's low ISO DR performance is still 1EV below the A7r/D800.
    Thank you! I don't think that D3S can be used as good example because it is three to four years older than say D800/D4S/Df but even if we ignore that we are not comparing same generations of technology D3s has better tonal range and color sensitivity per pixel than any of them, it is only DR that it has worse by a bit and only until ISO 400, after which it matches D4s and both seem to be significantly better than D800.

    That is with 12 MP technology that is 3-4 years older than sensor with more MP. Which makes me very curious what the results will look like with 12 MP technology that is newer than 36 MP one. Having A7S by the side of A7R will satisfy my curiosity. Now lets keep our fingers crossed that price is within reason.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Thank you! I don't think that D3S can be used as good example because it is three to four years older than say D800/D4S/Df but even if we ignore that we are not comparing same generations of technology D3s has better tonal range and color sensitivity per pixel than any of them, it is only DR that it has worse by a bit and only until ISO 400, after which it matches D4s and both seem to be significantly better than D800.
    I agree, but keep in mind that per-pixel metrics don't have any correlation to IQ since we work with images rather than individual pixels. This is why you'll see references to "per area" metrics when sensor performance is discussed and compared.

    Quote Originally Posted by ZoranC View Post
    That is with 12 MP technology that is 3-4 years older than sensor with more MP. Which makes me very curious what the results will look like with 12 MP technology that is newer than 36 MP one. Having A7S by the side of A7R will satisfy my curiosity. Now lets keep our fingers crossed that price is within reason.
    I'm very curious about how the A7s will perform as well. My guesstimate on the A7s price is $3,299.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    I agree, but keep in mind that per-pixel metrics don't have any correlation to IQ since we work with images rather than individual pixels. This is why you'll see references to "per area" metrics when sensor performance is discussed and compared.
    While we do work with images in the mind of this layman during capture and processing we work with "individual pieces of information" (pixels) so if color sensitivity / whatever of fatter pixel is better then file / final result should follow that too. I guess I will see for myself relatively soon.

    Quote Originally Posted by horshack View Post
    I'm very curious about how the A7s will perform as well. My guesstimate on the A7s price is $3,299.
    I too feel price is likely to be in that ballpark. If I had to guess my wishful thinking is $2,999.

  7. #207
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    Re: A7s!

    Quote Originally Posted by ZoranC View Post


    I too feel price is likely to be in that ballpark. If I had to guess my wishful thinking is $2,999.
    I don't really get why it should be any more than an A7?

    Can anyone enlighten me/us, Q: is a 12Mpixel FF sensor likely to be harder to make and hence have lower yields than the A7/r?
    Surely a lot of the development of the A7s is already done in the form of the A7/r ?

    I am not arguing the point, rather trying to understand why it should cost more than the A7/r?

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    Re: A7s!

    Quote Originally Posted by Tim View Post
    I don't really get why it should be any more than an A7?

    Can anyone enlighten me/us, Q: is a 12Mpixel FF sensor likely to be harder to make and hence have lower yields than the A7/r?
    Surely a lot of the development of the A7s is already done in the form of the A7/r ?

    I am not arguing the point, rather trying to understand why it should cost more than the A7/r?
    From a cost basis, the A7/A7r use sensors Sony already had - the A7r appears to be the identical sensor to the one sold to Nikon for the D800, and the A7 the same as the D600/D610/A99 (pixel design) with minor changes like PDAF sensor arrangement. Sony has manufactured a few million of these for Nikon and so their R&D costs have long since been amortized.

    The A7s is a brand new sensor design. The one-time R&D costs (NRE) are significant but its volumes will likely be far less than the A7/A7r sensors, even if Sony decides to sell it to other camera makers. That cost needs to be recaptured.

    From a value basis, the A7s is tailored toward high-end video production. The inclusion of S-Log2 is a good indicator of that. Such users would see more value in this product and are also less sensitive to price.
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    Re: A7s!

    In setting a price Sony find themselves dealing with crossover markets again - low Mp mainly stills shooters and the video people. What proportions are likely for these two groups? Will a 90% video user group be large enough sales wise?

    The 36Mp sensor first saw light of day in Feb 2012 and the 24Mp sensor debuted in Nikon D600 guise in Sept 2012 and in Sony's a99 at around the same time. These were landmark sensors in all the good things - DR, recovery, colour - and are aging very gracefully.

    The extra 2 stops of range at base was the key, but how much more would be really compelling as a trade-off for a return to 12Mp, for one camera users? If they ask three large it will have to be very special for stills photographers to get on board. I still expect a pleasant surprise price-wise, the body is tooled up already and the other a7 models are discounted.

    Note too this new sensor is, as far as we know, a Sony-only release at this stage. Maybe that is a victory of the camera division over the sensor outfit, which needs little help right now.

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    Re: A7s!

    Quote Originally Posted by philip_pj View Post
    In setting a price Sony find themselves dealing with crossover markets again - low Mp mainly stills shooters and the video people. What proportions are likely for these two groups? Will a 90% video user group be large enough sales wise?

    The 36Mp sensor first saw light of day in Feb 2012 and the 24Mp sensor debuted in Nikon D600 guise in Sept 2012 and in Sony's a99 at around the same time. These were landmark sensors in all the good things - DR, recovery, colour - and are aging very gracefully.

    The extra 2 stops of range at base was the key, but how much more would be really compelling as a trade-off for a return to 12Mp, for one camera users? If they ask three large it will have to be very special for stills photographers to get on board. I still expect a pleasant surprise price-wise, the body is tooled up already and the other a7 models are discounted.

    Note too this new sensor is, as far as we know, a Sony-only release at this stage. Maybe that is a victory of the camera division over the sensor outfit, which needs little help right now.
    May be that Sony could also put this sensor into their expensive movies cams ?

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    Re: A7s!

    It's a strange one, Annna, it might be very special. It's a good position for them to be in as many folks still really like that resolution level in their FF cameras, and it is no coincidence two of the most loved DSLRs are the classic 5D and the D700. We will soon see if Sony have anything up their sleeve besides their arm ;-)

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    Re: A7s!

    Quote Originally Posted by philip_pj View Post
    It's a good position for them to be in as many folks still really like that resolution level in their FF cameras, and it is no coincidence two of the most loved DSLRs are the classic 5D and the D700.
    I love my D700 for many reasons none of which have anything to do with resolution. If user interface and firmware of A7 series are any indicator A7S will still fall quite short of D700 when it comes to that.

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    Re: A7s!

    For sure tastes vary widely, for example I feel an acute revulsion just picking up a DSLR now! For me they are already part of the richness of the past, but for others - just right.

    ''However much resolution you guys throw, we will catch'' - Garret Brown talks with Philip Bloom and Sony re what happens next with 4K, might be of interest in this thread:

    Garrett Brown (inventor of Steadicam and Stanley Kubrick cameraman) is “excitied” about the Sony A7s! | sonyalpharumors

    Garret wants cameras as small as possible too, and: "We have an endless hunger for resolution."

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    Re: A7s!

    Quote Originally Posted by philip_pj View Post
    For sure tastes vary widely, for example I feel an acute revulsion just picking up a DSLR now! For me they are already part of the richness of the past, but for others - just right.
    Me, I choose tool based on how fit it is for task I have in mind, not based on anything else. But when tool is aspiring to be professional and has price to match I am expecting that tool to be well thought out, at least as well as tools that are few generations older than it is, and even better than tools that are much cheaper.

    For example, there is no excuse for A7 series to offer only two image ratios while EM5, camera two years older than it and half it's price, offers four, especially whan it's a simple firmware matter. That is what causes revulsion in me when I pick up my A7R. It's great perfromance deserves a well throught out wrapper around it, not one that makes you feel it has been designed by pop designers just out of high school for Hello Kitty generation with attention deficit disorder, not by high level professionals for high level professionals / amateurs.

    It makes me wonder what whole Sony chain of command was thinking when signing off on it, did they at all solicit and pay attention to opinion of people that used it long enough before doing so.

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    Re: A7s!

    Looks like Sony will ask big for the a7s release date - a major retail chain in Aust is taking orders - $A3499 (=$US3250).

    Sony A7s gets a pricing in Australia ($3499 AUSD). | sonyalpharumors

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    Re: A7s!

    Quote Originally Posted by philip_pj View Post
    Looks like Sony will ask big for the a7s release date - a major retail chain in Aust is taking orders - $A3499 (=$US3250).

    Sony A7s gets a pricing in Australia ($3499 AUSD). | sonyalpharumors
    I don't think this indicates anything yet. And if it does I will just patiently wait for price drops.

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    Re: A7s!

    Yep, the feeling seems to be that street US prices will be much more reasonable. It would have to be the final solution for video for them to price it out of the reach of most interested would be buyers. Only one dealer too, and not a particularly good one.

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    Re: A7s!

    Sony will be walking the fine line there. On one side it won't be mass demand item with matching volume price. On other side they will have to be careful not to price themselves out of the market, especially when one remembers what kind of fan base GH4, that will very likely be much cheaper, is having.

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    Re: A7s!

    2700 seems like the right price point to me. Just a gut thing
    Photography is all about experimentation and without it you will never learn art.

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    Re: A7s!

    Mirrorless rumours reports that A7s pricing will be announced on May 7th.
    It is rumoured to be around $1800, according to them. Fingers ( and everything else!) crossed.

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    Re: A7s!

    If that is the case IŽll get it FOR SURE!
    IŽve filmed a wedding this weekend and I kept thinking how awesome it would have been ot have had the A7s with me in certain shots.

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    Re: A7s!

    Quote Originally Posted by Rawfa View Post
    If that is the case IŽll get it FOR SURE!
    IŽve filmed a wedding this weekend and I kept thinking how awesome it would have been ot have had the A7s with me in certain shots.
    I'm in too
    Kind regards - Hulyss - hulyssbowman.com

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    Re: A7s!

    If that indeed does turn out to be the price, and if the reviews are good and I can live with the lack of phase detect autofocus, then I too would bite at that price. I'm hoping the lower res sensor will make the output from my old legacy lenses look better than a high res sensor.. the extra low light performance would be a bonus.

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    Re: A7s!

    I might be switch gears on it and get the A77II. I'd sell my A7 keep the A7r. Trying to build 2 different camera sets with the same glass. I'm a little in the air on what move is next.
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    Re: A7s!

    If $1800 is correct price my feeling is it will sell well.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Thank you! I don't think that D3S can be used as good example because it is three to four years older than say D800/D4S/Df but even if we ignore that we are not comparing same generations of technology D3s has better tonal range and color sensitivity per pixel than any of them, it is only DR that it has worse by a bit and only until ISO 400, after which it matches D4s and both seem to be significantly better than D800.

    That is with 12 MP technology that is 3-4 years older than sensor with more MP. Which makes me very curious what the results will look like with 12 MP technology that is newer than 36 MP one. Having A7S by the side of A7R will satisfy my curiosity. Now lets keep our fingers crossed that price is within reason.
    The A7s DxoMark results are out. As predicted its base ISO DR is below the higher-density D800/A7r, for reasons relating to large pixels described earlier in the thread (here). For High ISO though the A7s has monster DR - it's 1.7 stops better than the current leader (Nikon Df) @ ISO 102,400.

    Sony Alpha 7S sensor review: New low-light champ

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    The A7s DxoMark results are out. As predicted its base ISO DR is below the higher-density D800/A7r, for reasons relating to large pixels described earlier in the thread (here).
    Are we looking at same data or I am missing something? When I look at DXOMark's _non-downsampled_ data I see A7S having exactly same DR as A7R.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Are we looking at same data or I am missing something? When I look at DXOMark's _non-downsampled_ data I see A7S having exactly same DR as A7R.
    Per-pixel metrics have no significance since we render images (on a per-area basis) rather than individual pixels.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    Per-pixel metrics have no significance since we render images (on a per-area basis) rather than individual pixels.
    Maybe we need to discuss this differently. What is a dynamic range of a sensor to you? And why exactly we should ignore per pixel metrics? If DR on per pixel basis is exactly same for smaller and larger pixel can DR be increased at all just because we downsized the picture? And if answer is yes a) when does that stop, can DR become infinite?, b) will scene whose DR can't fit in range of "per pixel" fit once I take picture and downsize it? Will same scene taken with A7R and A7S with same exposure not have clipped highlights and shadows on A7R after downsizing if it had them clipped before and had them clipped on A7S?

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Maybe we need to discuss this differently. What is a dynamic range of a sensor to you? And why exactly we should ignore per pixel metrics? If DR on per pixel basis is exactly same for smaller and larger pixel can DR be increased at all just because we downsized the picture? And if answer is yes a) when does that stop, can DR become infinite?, b) will scene whose DR can't fit in range of "per pixel" fit once I take picture and downsize it? Will same scene taken with A7R and A7S with same exposure not have clipped highlights and shadows on A7R after downsizing if it had them clipped before and had them clipped on A7S?
    We should ignore per-pixel metrics because we render in terms of sensor area rather than pixels, whether we're rendering an image at a given PPI or cropping a subset of the image. The number of pixels contained in that area for a higher-density sensor will be more vs a lower-density sensor but the total area used from the sensor is the same (in millimeters from the sensor), thus the relevant sensor performance is the total light/noise in that area rather than the light/noise in the individual pixels from that area. The usual metaphor is buckets of water - one large bucket vs 3 smaller buckets but where the total volume of water held is the same.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    We should ignore per-pixel metrics because we render in terms of sensor area rather than pixels, whether we're rendering an image at a given PPI or cropping a subset of the image. The number of pixels contained in that area for a higher-density sensor will be more vs a lower-density sensor but the total area used from the sensor is the same (in millimeters from the sensor), thus the relevant sensor performance is the total light/noise in that area rather than the light/noise in the individual pixels from that area. The usual metaphor is buckets of water - one large bucket vs 3 smaller buckets but where the total volume of water held is the same.
    Will same scene taken with A7R and A7S with same exposure not have clipped highlights and shadows on A7R after downsizing if it had them clipped before downsizing and had them clipped on A7S?

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Will same scene taken with A7R and A7S with same exposure not have clipped highlights and shadows on A7R after downsizing if it had them clipped before downsizing and had them clipped on A7S?
    Highlights will be the same since total exposure is spread across the same area (ie, each individual A7r pixel will hold less light but in total hold the same amount of light as the fewer pixels of the A7s). The same is true for shadows except for the very deep shadows, where the A7r will hold the advantage at base ISO due to the lower read noise from the shallower pixel wells (even accounting for the higher theoretical read noise from more pixels having to be read) - the situation is reversed at High ISO where the A7s benefits from lower aggregate read noise from fewer pixels. This is why DR is better at base ISO for the A7r and better at High ISO for the A7s, and why this relationship holds true for most sensors of similar technology generations.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    Highlights will be the same since total exposure is spread across the same area (ie, each individual A7r pixel will hold less light but in total hold the same amount of light as the fewer pixels of the A7s). The same is true for shadows except for the very deep shadows, where the A7r will hold the advantage at base ISO due to the lower read noise from the shallower pixel wells (even accounting for the higher theoretical read noise from more pixels having to be read) - the situation is reversed at High ISO where the A7s benefits from lower aggregate read noise from fewer pixels. This is why DR is better at base ISO for the A7r and better at High ISO for the A7s, and why this relationship holds true for most sensors of similar technology generations.
    I feel we are not on same wave length here but I will try again: If DR of scene does not fit within DR of single pixel on A7R will it fit once picture is taken and downsized? Yes or no?

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    I feel we are not on same wave length here but I will try again: If DR of scene does not fit within DR of single pixel on A7R will it fit once picture is taken and downsized? Yes or no?
    For the highlight end, no. For the shadow end, yes (due to noise averaging from downsampling).

    A single A7s pixel will have a deeper well and thus can capture more light before it becomes saturated. But again we don't render individual pixels so the distinction is moot. And even though the A7s pixel will have more DR at the upper end (highlights due to more light captured), it will have less DR in the shadows due to the higher read noise associated with holding that extra light.
    Last edited by horshack; 17th June 2014 at 20:55.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    For the highlight end, no.
    Then the answer is no, downsizing won't make DR of a scene fit if it didn't fit before downsizing. Thus IMHO downsizing doesn't "buy me" more DR and consequently A7R will not / does not have more DR at base ISO once image is downsized.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Then the answer is no, downsizing won't make DR of a scene fit if it didn't fit before downsizing. Thus IMHO downsizing doesn't "buy me" more DR and consequently A7R will not / does not have more DR at base ISO once image is downsized.
    If your image consists of only a single pixel, sure. There aren't many creative photographic possibilities in a single pixel though.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    The A7s DxoMark results are out. As predicted its base ISO DR is below the higher-density D800/A7r, for reasons relating to large pixels described earlier in the thread (here).
    Thanks for the explanations re mpix & DR & ... .

    In looking at some recent cameras, the differences that seem to run counter to the more_pixels/area = higher_DR should be seen as evidence of some associated processing going on?

    I.p., taking the 16mpx Pentax K5 II as a base, w/16mpx,
    we can increase to 24 mpx per APS-C size with Sony A6000,
    or retain the 16mpx and increase density/reduce size per ...
    with the Olympus E-M5 (Sony sensor) or Panasonic GX7.
    YET, K5-a6000-EM5-GX7 DxO DR values are, resp.: 14.1, 13.1, 12.3, 12.2.
    ?

    -d.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    If your image consists of only a single pixel, sure. There aren't many creative photographic possibilities in a single pixel though.
    I don't see this sentence adding any value to / providing any insight into discussion, all I see it doing is avoiding straight topic about fitment of DR of scene. So it's obvious this will not take us anywhere. Maybe you could please show me / us with real world example how shot of scene whose DR was not fitting one of sensor would end up better DR wise from downsized A7R file than shot of same scene taken with A7S without any downsizing?

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    Re: A7s!

    Alongside the downsizing discussion, I am interested to see a range of images at lower ISO from the a7s - not much around at present - to get some appreciation of what MR was seeing in the files.

    If the new sensor delivers more of something not quite tangible in data that is nevertheless apparent in images, it might point to whatever else Sony has been working on in this latest of its FF sensors. Particularly with the better lenses (MR used the FE55), it could make a very good adjunct to the high ISO / video strengths of the a7s.

    Curious also to see whether the choice of 12Mp was one of efficiency - could the benefits find their way into the higher Mp sensors and densities favoured by Sony?

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    Re: A7s!

    Quote Originally Posted by philip_pj View Post
    ... I am interested to see a range of images at lower ISO from the a7s ... to get some appreciation of what MR was seeing in the files.

    If the new sensor delivers more of something not quite tangible in data that is nevertheless apparent in images ...
    That is one of the things I myself am always very interested to see about any new camera because having used number of cameras over the years left me with belief that there is much more to will I be happy with files from some camera or not than just what test numbers imply about sensor. I don't know what it is, I can't put my finger on it or describe it, like you said it is not quite tangible, but I do believe it is there as I believe I do "feel" it (I have had cameras whose sensor performance test numbers were implying I should have been equally, or more, happy with files from them as I was with ones from some other cameras I owned yet I never was nowhere near).

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Maybe you could please show me / us with real world example how shot of scene whose DR was not fitting one of sensor would end up better DR wise from downsized A7R file than shot of same scene taken with A7S without any downsizing?
    Here is a comparison of the D800 vs Df (and 6D) at ISO 100, 5 shots underexposed and pushed 5 stops in post, all downsampled to the same output size of 8MP. Since the DR of all 3 cameras exceeds the normal 7-8 stops rendered in a JPEG this is the only method to demonstrate base ISO DR. The Df is a proxy for the A7s since their base ISO DxoMark scores are very close, and of course the D800 for the A7r since they share the sensor. D800 on left, Df in the middle, 6D on the right.

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    Re: A7s!

    Quote Originally Posted by drofnad View Post
    Thanks for the explanations re mpix & DR & ... .

    In looking at some recent cameras, the differences that seem to run counter to the more_pixels/area = higher_DR should be seen as evidence of some associated processing going on?

    I.p., taking the 16mpx Pentax K5 II as a base, w/16mpx,
    we can increase to 24 mpx per APS-C size with Sony A6000,
    or retain the 16mpx and increase density/reduce size per ...
    with the Olympus E-M5 (Sony sensor) or Panasonic GX7.
    YET, K5-a6000-EM5-GX7 DxO DR values are, resp.: 14.1, 13.1, 12.3, 12.2.
    ?

    -d.
    You have to compare the same technology sensor in order to compare different pixel densities, which these all aren't. Absent identical technology implemented in varying densities the fallback is to compare the very best high density sensor (D800) to the very best low density sensor (A7s/Df) and in that comparison the pixel metrics I described with respect to both Low and High ISO hold true.

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    Re: A7s!

    The Camera Store posted their review of the camera:

    Sony A7S Hands-On Field Test

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    Here is a comparison of the D800 vs Df (and 6D) at ISO 100, 5 shots underexposed and pushed 5 stops in post, all downsampled to the same output size of 8MP.
    Thank you but I don't believe that is what I was asking for, especially not to compare _both_ being downsampled.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Thank you but I don't believe that is what I was asking for, especially not to compare _both_ being downsampled.
    Here are the raws if you'd like to perform your own comparison at a different resolution. The following link is only good for 5 days:

    D800 and Df ISO 100 -5EV Raws

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    Here are the raws if you'd like to perform your own comparison at a different resolution. The following link is only good for 5 days:

    D800 and Df ISO 100 -5EV Raws
    Thank you for the link but those files are still not illustrating what I was talking about. Was DR of scene you took within DR of a sensor to start with? Could you have taken that shot without underexposing while still fitting DR of a scene within DR of a sensor?

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Thank you for the link but those files are still not illustrating what I was talking about. Was DR of scene you took within DR of a sensor to start with? Could you have taken that shot without underexposing while still fitting DR of a scene within DR of a sensor?
    It's pretty close; based on the histogram there are deep shadows and the highlights are relatively close to clipping. Btw I offered you the raws as a courtesy; I'm guessing from our previous discussions that you're still not ready to embrace the pixel-level explanations regarding DR I presented earlier. I think your remaining sticking point is the fact that a larger pixel has a larger saturation capacity, so yes it can hold more light (highlights) vs a smaller pixel. But again, the total light capture of the smaller pixels will be equal to the single larger pixel, so the total saturation on a per-area basis remains the same. An analogy is a bedroom with one large window vs one with 4 small windows, but where the total surface area of the windows in both rooms is the same. In that scenario the same amount of light will enter each rooom.

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    Re: A7s!

    Quote Originally Posted by horshack View Post
    It's pretty close; based on the histogram there are deep shadows and the highlights are relatively close to clipping.
    Pretty close to clipping is not same as "clipped period". Previous one is "I am pretty close to losing data but I haven't lost any" while later one is "I lost data, period". Huge and crucial difference between the two.

    Quote Originally Posted by horshack View Post
    An analogy is a bedroom with one large window vs one with 4 small windows, but where the total surface area of the windows in both rooms is the same. In that scenario the same amount of light will enter each rooom.
    This discussion is not about how much light is trying to enter room, it is how much of it can be absorbed. Here is a different, maybe better, analogy: Water is pouring into one large bucket with enough volume that is making that bucket overflow. Placing three smaller buckets with same total capacity instead will not make any difference in how much water can be poured in before water starts getting spilled on a floor, they too will overflow at exactly same total volume amount as that single larger bucket.

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    Re: A7s!

    Quote Originally Posted by ZoranC View Post
    Pretty close to clipping is not same as "clipped period". Previous one is "I am pretty close to losing data but I haven't lost any" while later one is "I lost data, period". Huge and crucial difference between the two.
    That's true - I checked my image db and don't have a comparison with both at highlight saturation.

    Quote Originally Posted by ZoranC View Post
    This discussion is not about how much light is trying to enter room, it is how much of it can be absorbed. Here is a different, maybe better, analogy: Water is pouring into one large bucket with enough volume that is making that bucket overflow. Placing three smaller buckets with same total capacity instead will not make any difference in how much water can be poured in before water starts getting spilled on a floor, they too will overflow at exactly same total volume amount as that single larger bucket.
    That analogy works too, with the same result.

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    Re: A7s!

    Zoran, I am thinking you are a delightful cynic, lol.

    Watching the Camera Store video, Chris seems pretty clearly to suggest video shooters are going to be much happier than still shooters, but he has a leaning towards video it appears. Not surprised he gets 'blurry shots' with the a7/a7r the way he manically waves the camera around like a prop - which I guess it is.

    TBH, Sony's problem with the a7s for stills shooters is that the a7 and even more so the a7r (relative to res) are so competent already - in ALL light. He used a slow zoom, presumably FE 24-70, and took a lot of images *2-3 stops higher* EVs than I often do with the a7r:

    I max out at 6400/f2/1/60s in general for highly acceptable but obviously compromised quality, well handled with RAW post work...but if we say you get say, 2 stops more EV for same quality..it's either more DOF or a more 'secure' s/speed.

    Not much gets past those settings of mine, that is candle light or soft light shafts from far above skylights at best, and I seldom need longer FLs than 35-55mm which helps with h/holding. I always use wide-ish apertures in low light to take advantage of the preferred bokeh of my lenses (bought in part for just this characteristic) and to take out of play unwanted shadow details - I get images I prefer that way. Just thinking aloud here how I see it. At the moment anyway; all this stuff is a moveable feast, obviously.

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