pakodominguez wrote:David Kilpatrick wrote:
What I meant was that while zone matching Hi-Lo on the D7D, D5D, and A100 will produce a darker raw file (Hi) or lighter raw file (Lo) and then extract the extra information to JPEG from these, the Zone High 1, High 2 and Low on the A700 and A900 just uses a normal raw file. You do not get an exposure or ISO/EI gain change. It relies entirely on raw file headroom, as does the Brightness setting.
you get darker RAW while using DRO? not in Manual mode, I guess?
I barely use A/S/P modes, nothing against them. And I only use DRO for my personal work, not in events or portraits (but I used to shoot with Zone Matching all the time on the 7D) unless I can't control the light and the Bride's dress get overexposed. So I never had to deal with underexposed/darker RAW files...
The way DRO+ works with manual exposures must be different from the way it works with auto ones. It is suppose to communicate with the metering (40-zone mode) and in the A100, it was not able work without this (disabled in spot, centre weighted or manual). In the A700/A900 is can apparently work in any mode, even manual or spot metering, but I have no idea how it can do this properly - what if you totally under or over expose manually?
And I've checked - Zone -1, +1 and +2 may use a normal RAW (no gain adjustment) but - and this is REALLY uncalled for! - they change the exposure instead. So, you set ISO 100, put the camera on a tripod and block of the eyepiece, and meter with no Zone setting - 1/4 at f4. Shift to Zone +1 - 1/5 at f4. Shift to Zone +2 - 1/8 at f4. Shift to Zone -1 and get 1/3 at f4. The ISO stays at 100! In other words, if you set Zone Matching and then use a studio flash, or a hand-held exposure meter, you would get wrong exposure.
DRO does not change the exposure and can work in manual modes - but when matrix evaluative metering is enabled, it seems to cut the exposure so that the highlights are never overexposed. Clearly Sony has built in a whole range of behaviours so that DRO, DRO Advanced, DRO+ and Zone Matching will not be disabled by other camera settings, but you really are getting some very unpredictable results and misleading 'settings'. I have just found that DRO Auto reduced exposure by 1/3 stop, while DRO Standard and Manual +3 left it unchanged (for a one particular subject). Sony state that Zone Matching works with RAW on the A700 and A900 - sure, it under or over exposes! All they claim is that it helps prevent under or over exposure.
It seems that from changing sensor gain in the D7D, D5D and A100 Sony has moved to changing actual exposure given, to produce these modifications to contrast and range.
One thing is really clear from investigating this, if you want the lowest possible noise and the best files for raw conversion, don't rely on DRO or Zone Matching - shoot raw straight and get the exposure right! Don apparently shoots using manual settings most of the time, and really, that means he is bypassing these functions except when going for in-camera JPEGs. Ultimately, manual settings represent the best control you can have over the final result.
David
