Ok friends, time for me to put on my tinfoil hat.
I upgraded my trusty R7 to the latest firmware yesterday morning (1.3.0) and then put it through its paces to make sure things were ok.
One thing I noticed was that it seemed to be shooting fewer fps than before in H+ mode. Instead of the normal 15fps, I was getting 9-10fps.
"Huh," I thought. "Maybe I've got my settings wrong." Checked over everything. Changed lenses. Moved to a lighter environment. All the same. "Weird!"
So I did a bit of a test. I mounted a couple of different lenses and measured the fps at different shutter speeds. I used one shot AF so it wasn't tracking all the time. I kept aperture wide open - f4.5 on my EF 100-400ii. I balanced ISO for optimum exposure, starting at ISO 125 to match 1/50 shutter speed.
I conducted my test by establishing focus, then holding the shutter button for a few seconds (or until the buffer filled). I was in H+ mode, EFCS. I measured the fps by looking at how many frames were captured in a complete second of holding the shutter button, as per the recorded time in the EXIF data.
Here's what I found:
- 1/50sec: 9 fps
- 1/100sec: 10 fps
- 1/200sec: 11 fps
- 1/320sec: 11 fps
- 1/400sec: 11 fps
- 1/500sec: 14 fps
- 1/640sec: 15 fps
It also sounded even slower at lower shutter speeds than 1/50sec, but I didn't take a measurement.
I double checked my measurements in a different lighting environment (natural light - no anti-flicker mode). I also tested with both the LP-E6NH battery with full recharge performance and the LP-E6NH batteries. All the same results.
Now - this is different to what I had before. Naturally the fps drops if we go below a certain shutter speed, but I was definitely getting 15fps at 1/50sec before.
I should also mention that I still get 30fps in H+ electronic shutter at the above shutter speeds. I also get the full 15fps all the time in mechanical shutter mode. This just affects EFCS.
Here's my tinfoil hat explanation: has canon throttled the fps of the R7 in the above shutter speed range to address shutter shock in EFCS? I say this because my prior tests with shutter shock showed that it vanished by about 1/500 to 1/640sec. I wonder if canon have noticed this and implemented an "fps curve" accordingly.
To probe this idea further, I examined some shots at each of the listed shutter speeds, and indeed - there is now no/little evidence of shutter shock. It would seem that lowering the fps reduced the vibration of the shutter enough to mitigate the effects of shutter shock. This matches my prior observation that shutter shock is not present in H mode (8fps).
So two questions for you all:
- 1.) Can anyone else reproduce these findings on their R7?
- 2.) If so, do you think my explanation is legitimate?
I actually think this is a pretty good solution if these findings bear out in reality. It means that I wouldn't have to worry about switching back and forth between H+ and H modes to avoid shutter shock. I could just leave it in H+ mode and trust the camera to supply the fps needed for a vibration-free image. For fps critical applications necessitating a high shutter speed, I'll automatically be getting the full 15fps without having to think about my settings. Pretty good if true!
