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Thread: A900 findings

  1. #1
    hardloaf
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    A900 findings

    As promised here are some A900 findings which I've accumulated so far.

    1. Optimal ISO range is 320-800, 320 is the best, top limit depends more on your converter and taste, so decide for yourself. This means that in this range you don't underexpose and bump ISO if needed, but you don't go above the top limit and start underexposing. If you need high quality low ISO go with good ND or polarizer.

    2. Wouldn't bother with ETTR - this camera is better than that, just shoot as you did on film, by meter, and your colors will be better.

    3. UniWB is highly recommended, especially if you shoot scenes with dominating red or have weird light. Daylight is not safe either - more depends on actual colors in picture, so UniWB is a good safety guide.

    4. Use Zone setting to adjust light meter bias - it goes in 0.5EV steps and -1 opens shadows at cost of highlights, 1 or 2 gives more space for highlights at cost of shadows.

    5. You'll have hard time finding lenses which can outresolve this sensor. Not only because it is 24M, but also because it has weak anti-aliasing filter. In my experience Sony 50/1.4 is very good at this, Zeiss 135/1.8 is simply outstanding. I also like manual Zeiss Flektogon 35/2.4 through chipped M42 adapter, even though I'm not sure if it can outresolve the sensor. There should be others of course. This also raises requirements for tripod/head if you need really sharp shots - even with 2 sec. delay and mirror lock up, remote release and tripod I still get slightly different level of sharpness in two consecutive shots sometimes.

    6. For M42 use chipped adapters programmed for each worthy lens exclusively. James Lao is recommended (http://eadpt.cn/eadpen.htm). I'm not affiliated with him and had problem with his product, but in my opinion he is still the best in this regard. You'll have working metering and proper EXIF info, both are important.

    7. NR for long exposures - so far I don't find it useful at all, if your converter can suppress hot pixels better use converter, but jury is still out here. Need to do more testing.

    Shameless plug goes here:
    If you are on Mac, you may find that my converter (RPP, link in the signature) can "magically" make your A900 produce even more details, better noise and colors and higher DR. Give it a try

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    Re: A900 findings

    Thanks Andrey,

    very interesting information!

  3. #3
    Subscriber Member Georg Baumann's Avatar
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    Re: A900 findings

    How interesting indeed, thanks for your findings. I did not now about your SW and will give it a shot. Would you think your SW to provide better results than C1?

    Hoswever, I am struggling to understand your point of not shooting ETTR.

    Why would that be? Are you saying the metering from the alpha is not good enough and you do recommend to use an external lightmeter like a Seiko or similiar instead, or did I misunderstand that?

    Best wishes
    Georg

    P.S.
    Very kewl Avatar!

  4. #4
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Georg Baumann View Post
    How interesting indeed, thanks for your findings. I did not now about your SW and will give it a shot. Would you think your SW to provide better results than C1?
    In my opinion it's better, but what else could you expect from it's author? It's very different and requires learning for sure.


    Hoswever, I am struggling to understand your point of not shooting ETTR.

    Why would that be? Are you saying the metering from the alpha is not good enough and you do recommend to use an external lightmeter like a Seiko or similiar instead, or did I misunderstand that?
    No, I meant using camera light meter (or external one if you care), but don't push histogram to the right and use camera light meter as it's intended, i.e. expose most important part of a picture around camera midpoint.
    ETTR had some reasons for old cameras with low DR - noise was too close to the midpoint and we had to do this to minimize it. With late cameras which have over 9 stops of DR ETTR is very harmful for colors - midpoint is the most colorful place in A900 gamut and noise is not an issue there any more. In A900 gamut slowly narrowing down from midpoint to shadows and very quickly narrowing down from midpoint to highlights. This means that brightest stop of the camera range has most of colors gone forever and they cannot be restored with negative exposure compensation. I'd say all color critical parts should be below top 1.5 stops. Veiling glare from lens and sensor are the culprits here.

    Very kewl Avatar!
    Thanks

  5. #5
    Subscriber Member Georg Baumann's Avatar
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    Re: A900 findings

    Interesting.

    I can not test that now, but as soon as my alpha is there I will try it.

    I still think, because the brightest levels have the most data, it should be a valid technique. Noise being less an issue with modern cameras, agreed.

    But when exposed to the right and then using fill light in LR for example to open up shadows..... well.... that is what I often did so far to good result.

    Now I am curios what other fellow alpha900 user found in that respect.

  6. #6
    Subscriber Member Georg Baumann's Avatar
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    Re: A900 findings

    Quote Originally Posted by hardloaf View Post
    - even with 2 sec. delay and mirror lock up, remote release and tripod I still get slightly different level of sharpness in two consecutive shots sometimes.
    I would think 2 sec is not enough, the longer your focal length the more I would add to that time. The minimum I use is 4 second for wide angle and 8 seconds for really long shots.

    Increasing the delay should provide more consitent results.

  7. #7
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Georg Baumann View Post
    Interesting.

    I can not test that now, but as soon as my alpha is there I will try it.
    You can test everything with any more or less recent good camera, I'm sure you have one already.


    I still think, because the brightest levels have the most data, it should be a valid technique. Noise being less an issue with modern cameras, agreed.
    Squeezing scene with high DR into sensor or film range is a totally valid approach when needed, same as exposing for shadows. ETTR however assumes that it's always better to shift histogram to the right, even when your scene is only 6 stops wide and sensor is 9.5 stops wide. You probably already noticed before that slightly underexposed shots can be amazingly colorful even after exposure correction and I definitely noticed that ETTR shots can be very dull after correction even if there was no clipping. So my point is that ETTR is not always better and shouldn't be used unconditionally. The whole approach that you need to pay attention only to highlights is very limiting - what's really important is were we place critical part of a picture on a sensor range. This critical part can be anywhere - in shadows, highlights or in the middle and we should understand that moving it closer to the middle gray will improve it's appearance and try our best. That's it

  8. #8
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Georg Baumann View Post
    I would think 2 sec is not enough, the longer your focal length the more I would add to that time. The minimum I use is 4 second for wide angle and 8 seconds for really long shots.

    Increasing the delay should provide more consitent results.
    I'll try it - thank you for the tip. I always used couple of seconds and it worked for me, time to change old habits I guess

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    Senior Member douglasf13's Avatar
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    Re: A900 findings

    Thanks, Andrey. As far as camera metering, would you say that metering middle grey at +.5 ev, or detailed whites at +3ev, makes sense? Iliah mentioned this a couple of months back.

  10. #10
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by douglasf13 View Post
    Thanks, Andrey. As far as camera metering, would you say that metering middle grey at +.5 ev, or detailed whites at +3ev, makes sense? Iliah mentioned this a couple of months back.
    I think it's more matter of taste and habits. Range -1 .. +1 from middle gray is the best one for colors, so pick your placement depending on conditions. I'm staying with A900 default because I often shoot outside and current 3.2EV gray point works fine for me - less clipped highlights.

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    Senior Member edwardkaraa's Avatar
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    Re: A900 findings

    Completely agreed with Andrey. I have done some tests in the past on my 1Ds2 and found exactly the same regarding exposing to the right. The A900 seems no different. Now I try to get the right exposure (pun intended ) in the camera. The camera meter is very accurate as compared to a Sekonic external meter in reflective mode, but I found that incident readings work best with the A900.
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    Workshop Member kuau's Avatar
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    Re: A900 findings

    Edward are you shooting in Matrix Mode most of the time or reflective? Or.. are you using a sekonic external meter incident mode?

    Steven
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    Senior Member edwardkaraa's Avatar
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    Re: A900 findings

    Hi Steven,

    I try to take incident readings whenever I have the time. If not, I find the camera meter to be very trustworthy, however reflective light readings should always be interpreted depending on subject matter. I realized that many claims, especially on DPR, that the A900 meter underexposes are baselss. Many new comers to photography expect the meter to think for them, unfortunately.
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    Senior Member Robert Campbell's Avatar
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    Re: A900 findings

    Hardloaf, are you saying that ETTR is outdated for all modern DSLRs?
    Sláinte

    Robert.

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    Administrator, Instructor Guy Mancuso's Avatar
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    Re: A900 findings

    Bottom line on in camera cam meters almost every company Canon, Nikon and my bet Sony as well tune the meters to underexpose slightly to protect themselves from about a million daily complaints from blown highlights. Honestly this is just a fact of life and the same with using AA filters with complaints by the millions from Moire. Seriously and I don't mean too offend anyone but these cameras are designed with the amateurs in mind that just stick the camera on auto and go, plus jpeg all the way. That is the design mindset. Obviously they are made for Raw shooting and such as well and in more capable hands can adjust at will. But also every Raw converter will render each Raw differently as well and some will be more underexposed and some will not. The end of the day there is no standard and you will have to fine tune for your raw converter. My Phase back is about 1.25 stops under in LR and slightly under in Raw developer by about 1/2 stop. Also on meters what many folks don't even think about is where the weight area of the meter sits, so that throws another curve in the mix.
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    Re: A900 findings

    Quote Originally Posted by hardloaf View Post
    I'll try it - thank you for the tip. I always used couple of seconds and it worked for me, time to change old habits I guess
    what are you using to release the shutter? Reichman's review sort of blasted Sony for the remote because the sensor is in the front of the camera.

  17. #17
    Senior Member edwardkaraa's Avatar
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    Re: A900 findings

    Quote Originally Posted by TEBnewyork View Post
    what are you using to release the shutter? Reichman's review sort of blasted Sony for the remote because the sensor is in the front of the camera.
    The remote that is provided with the camera is not intended to be used as a cable release. It's only for taking pictures of yourself when you're in front of the camera or playing a slide show Moreover it doesn't even lock the mirror up. You'll have to buy a normal cable release like I did
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  18. #18
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Robert Campbell View Post
    Hardloaf, are you saying that ETTR is outdated for all modern DSLRs?
    Essentially yes.

  19. #19
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by TEBnewyork View Post
    what are you using to release the shutter? Reichman's review sort of blasted Sony for the remote because the sensor is in the front of the camera.
    I bought a wired one on ebay. $5 or something

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    Workshop Member ptomsu's Avatar
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    Re: A900 findings

    Quote Originally Posted by Guy Mancuso View Post
    Bottom line on in camera cam meters almost every company Canon, Nikon and my bet Sony as well tune the meters to underexpose slightly to protect themselves from about a million daily complaints from blown highlights. Honestly this is just a fact of life and the same with using AA filters with complaints by the millions from Moire. Seriously and I don't mean too offend anyone but these cameras are designed with the amateurs in mind that just stick the camera on auto and go, plus jpeg all the way. That is the design mindset. Obviously they are made for Raw shooting and such as well and in more capable hands can adjust at will. But also every Raw converter will render each Raw differently as well and some will be more underexposed and some will not. The end of the day there is no standard and you will have to fine tune for your raw converter. My Phase back is about 1.25 stops under in LR and slightly under in Raw developer by about 1/2 stop. Also on meters what many folks don't even think about is where the weight area of the meter sits, so that throws another curve in the mix.
    For serious shots I find myself more and more using manual exposure and slowly working myself into the range where I have the right lightning seen on the camera monitor (which usually is very tricky to judge) and the histogram covering the whole area and not exceeding to the right or to the left.

    Once this is set up I can thn work without controlling exposure for a whole while

    Especially in my M8 this proves to give optimum results. Will see how good this works in the A900

  21. #21
    Senior Member douglasf13's Avatar
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    Re: A900 findings

    Andrey, I think it should be mentioned that: one, I assume you're speaking of spot metering, and not matrix. Two, sometimes not using ETTR means that highlights may be blown out. I've seen many misunderstand ETTR and not let any highlights blow at all, which results in the underexposure of midtones/subject. Your general advice of making sure that midtones are in the right place sounds good to me.

  22. #22
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Guy Mancuso View Post
    Bottom line on in camera cam meters almost every company Canon, Nikon and my bet Sony as well tune the meters to underexpose slightly to protect themselves from about a million daily complaints from blown highlights. Honestly this is just a fact of life and the same with using AA filters with complaints by the millions from Moire. Seriously and I don't mean too offend anyone but these cameras are designed with the amateurs in mind that just stick the camera on auto and go, plus jpeg all the way. That is the design mindset. Obviously they are made for Raw shooting and such as well and in more capable hands can adjust at will. But also every Raw converter will render each Raw differently as well and some will be more underexposed and some will not. The end of the day there is no standard and you will have to fine tune for your raw converter. My Phase back is about 1.25 stops under in LR and slightly under in Raw developer by about 1/2 stop. Also on meters what many folks don't even think about is where the weight area of the meter sits, so that throws another curve in the mix.
    Gray point is the base point which light meter is calibrated to. There used to be an old film 18% gray standard (2.5 stops from saturation point at the top), than at some moment all vendors switched to 12.7% (about 3 stops). They all round up them differently, so there is some small variations, f.e. it can be 12.5%. Then they switched to even lower values. My A900 is about 10% gray (3.33 stops), but it looks like there is slight variations in different camera samples. This all is based on green channel only (not sure if they use same kind of green as on sensor though).

    You right that this number regulates amount of captured highlights, but I don't think that it has anything to do with amateurs - all light meters have their gray point and that's how they work. I don't know exact reasoning behind 18% gray, but this is the area which humans like a lot and where we have highest sensitivity to details and colors. Where 12.7% comes from I can only guess, probably something with getting round power of 2 which is important for digital (it's very close to 2^3=8). Comes with a "bonus" of more highlights at cost of shadows, but requires compensation because 12.7% perceived as underexposed. Now recent crop of cameras like A900, D3X, 5D2 went even farther. A900 calibrated to 10% gray and picture exposed around this number will definitely look dark. Most likely vendors just optimized light meters to place gray point in the best spot of a sensor, which is a good thing - they can afford this because sensors are better and shadows are much cleaner now. Bad thing here is that pictures need to be compensated now. In RPP this means Compressed exposure correction about 0.7-0.8 for A900. It absolutely must be corrected!

    Other converters do this behind a curtain and apply some exposure corrections automatically, usually badly and based on their own (mis)understanding, tone curve is getting involved so that's were all this confusion comes from. I completely disagree with this approach and in RPP you'll actually see picture exactly as it was captured and you need to define your correction specifically and make it default.

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    Senior Member douglasf13's Avatar
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    Re: A900 findings

    Andrey, if you have a scene with very low dynamic range that has no risk of clipping shadows and highlights, where do you place middle grey? -1, 0, or +1 EV? Which is the ideal setting for best color, noise, resolution, etc? I'm debating whether there is any reason for me to be using Zone -1. I've been metering middle grey at +0, or essentially +.5 with Zone turned off. Thanks.

  24. #24
    Senior Member edwardkaraa's Avatar
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    Re: A900 findings

    I think the 18% came from slide film and color printing paper latitude of 5 f/stops. Slide film had usually a latitude of 2 1/3 over and 2 2/3 under. I also heard that Sekonic grey point is currently at 13% instead of 18%, probably to compensate for the increase in modern film latitude. I think Andrey is making a very valid point about meters. I tested my A900 meter against a Sekonic and the readings were practically similar (if anything, the A900 overexposed very slightly over the Sekonic by 1/10 to 1/20 f/stop). This means that while the meter reading is basically correct, the real iso sensitivity of the camera may not be exactly as advertized. DXOmark suggests about 1/2 stop below advertized numbers.

    This discussion is getting more and more interesting
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    Senior Member Quentin_Bargate's Avatar
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    Re: A900 findings

    Fascinating, but 320 ISO best? I think not.

    Quentin
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    Re: A900 findings

    Quote Originally Posted by Quentin_Bargate View Post
    Fascinating, but 320 ISO best? I think not.

    Quentin
    I think an awful lot of this discussion hinges around the definition of the word
    best
    Which may be different for different people (certainly is for me).
    The 'no ETTR' idea is music to my soul, because I'm more interested in colour and an absence of blown highlights than I am in shadow noise.

    It's all really interesting and constructive though

    Just this guy you know

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    Senior Member douglasf13's Avatar
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    Re: A900 findings

    Agreed, Jono. Some may find the very small difference in noise between ISO 200 and 320 more important than destroyed shadow detail.

    As far as ignoring ETTR, I think we need to be careful with this sentiment, as there are different definitions of this term, as well as the fact that some raw converters do a better job than others. Some view ETTR as exposing everything to the right without blowing any highlights, but that can be fundamentally flawed, because it forces some shooters to try to save insignificant highlights, like speculars, which can lead to underexposure of midtones. Overall, I think Andrey's recommendation to keep the subject/midtones in the Zone 4,5 or 6 range is a good way to look at things. Unfortunately, from what I've seen, matrix metering isn't a consistant way of assuring this.
    Last edited by douglasf13; 3rd June 2009 at 04:32.

  28. #28
    Senior Member Eoin's Avatar
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    Re: A900 findings

    Quote Originally Posted by Quentin_Bargate View Post
    Fascinating, but 320 ISO best? I think not.

    Quentin
    Hmmm!, I like shooting available light portraits, I also happen to think for my criteria 320 ISO offers the best compromise in these situations. I am too lazy to bother changing back down to a lower ISO because quite frankly I don't see that much difference in print, infact I quite prefer the slightly different structure it imparts to monochrome prints.

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    Re: A900 findings

    Quote Originally Posted by hardloaf View Post

    Other converters do this behind a curtain and apply some exposure corrections automatically, usually badly and based on their own (mis)understanding, tone curve is getting involved so that's were all this confusion comes from. I completely disagree with this approach and in RPP you'll actually see picture exactly as it was captured and you need to define your correction specifically and make it default.
    Which takes us back to the thread two weeks ago (when I got the camera) when we talked about setting camera defaults and in conjunction, zeroing out the Lightroom "behind the scenes" corrections.

  30. #30
    Senior Member douglasf13's Avatar
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    Re: A900 findings

    Right on, although keep in mind that those LR settings are a rough estimate, and they won't be nearly as accurate as RPP in showing what your RAW really looks like.

  31. #31
    Subscriber Member Georg Baumann's Avatar
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    Re: A900 findings

    Anyone around here had a chance to compare results of RPP and C1?

    Andrey, I realise you are the manufacturer, however, I would think you did make some form of empirical studies comparing your product with the output of other converters, and it was that I was curious about.

    In what fields did you find RPP provides an advantage over C1 for example.

    I am not biased at all, I have not used C1 or RPP, I only used Sinar xposure and LR.

    Having said that, I am now shooting with the alpha and of course I am interested in best possible file quality. I am also shooting with a phase one, did you have a chance to try your RPP with DB's from phase one?

    On a side note, I think it is great to have a developer here in the fora who is willing to share his insights and views. Thanks for that Andrey!

  32. #32
    Senior Member Robert Campbell's Avatar
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    Re: A900 findings

    What I've got so far -- and I don't have a Sony -- is:

    1. Advice to shoot at base ISO is/may be wrong -- and if you thought it was 100, well it's something else

    2. ETTR is/may be wrong

    3. 18% grey is something else

    Any other paradigm shifts -- before I give it all up?
    Last edited by Robert Campbell; 3rd June 2009 at 06:23.
    Sláinte

    Robert.

  33. #33
    Shelby Lewis
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    Re: A900 findings

    Ok... I'm not going to refute much of what has been said here (from a technical viewpoint)... but here are my observations, so far, from a month's work with the a900 in paying situations (even if that makes no difference ).

    I think exposure optimization has more to do with photographic intent than technical means. I use ETTR to keep the amount of shadow noise to a minimum in my photographs to a point. Blindly using it is just being ignorant, if you ask me, but using it smartly to control the dynamic range of a scene is essential at times if you need the most data to work with at the beginning of the post process.

    In wedding work, I'm often in situations where the majority of the scene is in deep shadow. I'd rather ETTR to keep chroma noise at bay amap than to lose even more detail by having to deal with excessive noise (dictated by the scene)

    I totally agree about the color hit you can take with ETTR... given that the scene isn't all highlights. There are high key scenes that beg for ettr and underexposing deeply and boosting in post (the opposite of ETTR) will (in my book) yield poorer results than an ETTR exposure.

    Lastly... and I need to test this more... but 320 is a great ISO on the a900 but i see way to much texture in broad smooth areas (skies, for example) to warrant it's use in many situations. Even if the camera isn't optimized below 320, the camera does take a noise hit at 320... ettr or not.

    For me... exposure is just as much a question of intent as it is about optimization... and I make that decision taking a BUNCH of factors into considerations.

    Great topic!

  34. #34
    hardloaf
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    Re: A900 findings

    Douglas,
    Quote Originally Posted by douglasf13 View Post
    Andrey, I think it should be mentioned that: one, I assume you're speaking of spot metering, and not matrix. Two, sometimes not using ETTR means that highlights may be blown out. I've seen many misunderstand ETTR and not let any highlights blow at all, which results in the underexposure of midtones/subject. Your general advice of making sure that midtones are in the right place sounds good to me.
    Yes, for simplicity let's stick to spot metering. Matrix is more complex case, but it's still based around the same gray point as spot metering.

    Regarding ETTR I already mentioned this, but let me rephrase - ETTR as universal approach for all kinds of shooting is wrong and unfortunately most of people treat it this way no matter what and how they shoot. It's easy to understand and there is even some technical explanation behind it, but in fact it doesn't tell the whole story.
    ETTR as approach when we are trying to open shadows without clipping highlights is a valid technique when needed and as long as we understand what we gain and what we loose there is absolutely nothing wrong with that.

    So now about the abbreviation - it's obviously ambiguous and to avoid problems I'd prefer not to use it at all. After all idea to expose for shadows is as old as the world itself, idea that sometimes highlights cannot be clipped is also totally banal, so why do we really need that abbreviation? Just understand what you are doing and expose consciously

  35. #35
    Shelby Lewis
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    Re: A900 findings

    Quote Originally Posted by hardloaf View Post
    Just understand what you are doing and expose consciously
    Preach On, Brother!

    That was a much shorter way to say exactly what I said. I should have let you say it first

  36. #36
    hardloaf
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    Re: A900 findings

    Douglas,
    Quote Originally Posted by douglasf13 View Post
    Andrey, if you have a scene with very low dynamic range that has no risk of clipping shadows and highlights, where do you place middle grey? -1, 0, or +1 EV? Which is the ideal setting for best color, noise, resolution, etc? I'm debating whether there is any reason for me to be using Zone -1. I've been metering middle grey at +0, or essentially +.5 with Zone turned off. Thanks.
    This is again matter of taste - if you used to Zone -1 keep using it, this is just a half stop away from default and it's not enough to cause any major problems with colors.

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    Re: A900 findings

    sounds like a review of the zone system would serve many.

    with a spot meter, i typically set caucasion flesh tones at Zone VI, one stop over Zone V, V being what my spot meter would record on a neutral gray (18%) card, and what my incident light meter would show.

    let the shadows and highlights fall where they may depending on the range of the scene.

    one could test their ISO setting by shooting a gray card, metering off the card, and printing it with no exposure change. then compare the gray card to the print.

    in practice, it is easier to shoot the gray scale card, still metering off neutral gray.

  38. #38
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    Re: A900 findings

    Quote Originally Posted by edwardkaraa View Post
    I think the 18% came from slide film and color printing paper latitude of 5 f/stops. Slide film had usually a latitude of 2 1/3 over and 2 2/3 under. I also heard that Sekonic grey point is currently at 13% instead of 18%, probably to compensate for the increase in modern film latitude. I think Andrey is making a very valid point about meters. I tested my A900 meter against a Sekonic and the readings were practically similar (if anything, the A900 overexposed very slightly over the Sekonic by 1/10 to 1/20 f/stop). This means that while the meter reading is basically correct, the real iso sensitivity of the camera may not be exactly as advertized. DXOmark suggests about 1/2 stop below advertized numbers.

    This discussion is getting more and more interesting
    Makes sense. I think it's more like 1/3 stop below though, so shooting 320 means underexposed 250. All vendors got themselves into some funny game - D3X does the same (1/4 of a stop lower), 5D2 (1/2 stop lower). It may look like some marketing ploy, but actually guys are just messing around since there is no standard for ISO in Raw.

  39. #39
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    Re: A900 findings

    Georg,
    Quote Originally Posted by Georg Baumann View Post
    Andrey, I realise you are the manufacturer, however, I would think you did make some form of empirical studies comparing your product with the output of other converters, and it was that I was curious about.

    In what fields did you find RPP provides an advantage over C1 for example.
    It resolves more details, produces better colors and noise and it's much more predictable because it doesn't do anything if not asked to and you have full control over your image. It's different though and past experience with other converters doesn't help at all - no real time preview and workflow should be different to be efficient.

    Having said that, I am now shooting with the alpha and of course I am interested in best possible file quality. I am also shooting with a phase one, did you have a chance to try your RPP with DB's from phase one?

    On a side note, I think it is great to have a developer here in the fora who is willing to share his insights and views. Thanks for that Andrey!
    P20, P20+, P21, P21+, P25, P25+, P30, P30+, P45, P45+ are fully supported and I have very positive feedback from those who work with them. You need a fast computer though, Mac Pro is highly recommended for everything above 16M.

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    Subscriber Member Georg Baumann's Avatar
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    Re: A900 findings

    <grins> I am installing a 8 core 2.66 Ghz Nehalem with 32 Gig Ram as I type here, that should do.

    Thanks Andrey, no real time preview means exactly what? I change parameters xyz and do not get to see the effect in the preview?

    <sorry, I should really DL your RPP and give it a go before asking questions. >

  41. #41
    hardloaf
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    Re: A900 findings

    Quote Originally Posted by Georg Baumann View Post
    <grins> I am installing a 8 core 2.66 Ghz Nehalem with 32 Gig Ram as I type here, that should do.
    Yep, not too shabby

    Thanks Andrey, no real time preview means exactly what? I change parameters xyz and do not get to see the effect in the preview?

    <sorry, I should really DL your RPP and give it a go before asking questions. >
    This means you change settings and click Apply to see them. Takes some time to get used to and get feeling over numbers.

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    Re: A900 findings

    I'm finding this discussion extremely interesting. I'm 100% amateur, recently started doing some medium format film and have a grdII.

    Tried to post something about this in http://forum.getdpi.com/forum/showthread.php?t=7769 , which got ignored, probably understandably, as it was a somewhat confused post.

    To cut a long story short. I ended up measuring the grey level percentages throughout the dynamic range of the GRD II, and for all iso values, in conjunction with the Aperture default B&W conversion. So now I know very precisely what to expect, and where I can go from there in with Aperture. Also appreciate the massive differences between film and digital, and the essential uselessness of the default metering decisions (I'm sure this is A LOT better in the sony).

    Enjoying my photography a lot more since. Should also mention that the inspiration to do the above came after reading the Ansel Adams books, and write down a zone system for the GRDII

    Anyhow, was glad to read all the informative posts in this thread.
    Last edited by sizifo; 3rd June 2009 at 17:02.

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