I had an event to shoot last night, a dinner monthly meeting of an ex-pat club that I belong to. 227 attended representing 36 countries for the formal dinner and reception. I used both the D800 and D7000 and took just one flash, a SB900 and three lenses. I have been very happy with both cameras in similar situations but last night was the first time to use flash on both, the same flash.
Of the 460 shots combined, a couple of the D7000 files were deleted for missing focus, 1 from the D800. I had the 70-200 on the D7000 and 24-70 on the D800. Settings for flash on both cameras were typical for events: manual, 320 ISO, 1/80, f/4, no EC, RAW, Standard PC
Even by casual observation before downloading, the exposure was much more consistent with the D7000. In fact, not one needed post processing for exposure level, all really nicely exposed. The D800 in the same scenes but wider field of view resulted in less consistency. A typically group shot, with the same people background and lens, repeated for 3 frames, each would have up to .5 to 1 stop difference or random variation, none wildly off but at least 1/2 needed some sort of correction in post to look the same. I noticed it mid point in the evening so I switched lenses between the cameras and the D7000 was still more consistent. I do not expect the same exposure with different conditions or in-frame elements but when all conditions, scene, subjects, ambient light etc is the same between shots, this surprised me.
The image quality was very good on both and zooming in, it was obvious which was 36mpx. Since I tweak exposure on most shots in post whether they need it or not, I never noticed inconsistency when using flash. Switching the Auto ISO on both for ambient light shots without the flash, in a better lit part of the restaurant, the D800 was much more consistent and in getting usable shots as I have come to expect. The girls naturally all lined up for portrait style or full figure photos after the main event and dinner was over and both resulting in really nice casual portraits with the 70-200 or 85 1.4. I switched to manual flash for a few of the shots, relying on the camera meter for estimates of power needed. Those were consistent between all the shots. The SB900 has its own metering system so the only control the camera has is of the ambient exposure and any Flash composition dialed in. So not sure what is happening. Anyone else notice any D800 inconsistency with iTTL? Stan St Petersburg Russia
#2. "RE: D800 flash exposure....interesting observation..." In response to Reply # 1
St Petersburg, RU
When shooting in iTTL mode, Matrix is my standard and for slow shutter like 1/80 I normally use Rear Sync. There was nothing in the resulting images to suggest a problem and I would not have noticed the difference except this time, I was sharing the SB900 between two cameras and noticed the difference in consistency. I tried some test shots tonight with the D800 and same flash, with same settings and exposure frame to frame was closer but still not as consistent as the D7000. As I mentioned, flash is the only mode I have seen this, ambient light shot tonight and at the event were fine.
I extended the experiment tonight by getting 2 SB900's off cameras using fully manual and there was almost no difference in the 20 or so frames with the D800. There was no obvious difference when switching SB900's.
I tried a couple with ND filters and wide open 2.8, thinking there might be a slight case of sticking aperture but I could not tell anything for sure with only a few frames. I am starting to think the D800 is normal and the D7000 is just abnormally consistent;>)
I do not consider it a problem, just an observation, a curiosity more than a complaint. After using both for the last two events(I've taken the D7000 in the past but not brought it out when shooting the D800) I find that I really like that combination. Stan St Petersburg Russia
#4. "RE: D800 flash exposure....interesting observation..." In response to Reply # 0
Stan, when you say settings for both cameras were manual, did you also use manual focus? If not, a D800 autofocus characteristic associated with matrix metering that could lead to exposure differences is the tendency of the focus sensors to influence the exposure.