OK, I have now performed several tests on the 100D using the latest April 27-th build that I found in Danne's repository. I used the SanDisk Extreme Pro 64 GB/95MB/s card, with the preview mode set on Auto which provides normal Live View and allows good framing. Here is some feedback:
1) In the RAW video mode, at 24 and 30fps, the build is as stable as the April 20-th build discussed above (see download link in my post #1221). The camera performs very well in the Normal uncropped, 5x-magnification and Movie Crop modes and provides continuous recording with the 8...11 bit and 12 bit lossless compression, even at the maximum 2520x1080 resolution. No glitches and no corrupt frames.
2) At 42 fps operation is not so stable. In the normal uncropped mode, at 1736x976 resolution, sometimes I get clips without a single corrupt frame, sometimes there are a few corrupt frames. Mostly, corrupt frames occur after I have changed some settings (ISO, Normal to Movie Crop Mode and back, etc.) In the Movie Crop Mode, except for corrupt frames, I get lots of malloc error messages running through the screen during recording. These disapper only after a battery pull.
BAD NEWS:
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3) In the Normal uncropped mode, there is a serious exposure problem when frame rate is changed from 24 to 42 fps. The screen gets dark and this makes framing and subject tracking impossible. Exposure reduction by about one stop would be normal since the shutter speed increases from 1/50-th to 1/84-th of a second due to the higher frame rate. However, this is not the case. I need to increase the exposure by almost 4 stops to get the clip properly exposed. This makes indoor shots almost impossible since the ISO has to be boosted to 3200, even 6400 to obtain correct exposure. In that case, clips get quite noisy. I hope, this can be fixed. Interestingly, this exposure bug does not occur in the 5x-magnification mode where exposure is perfectly normal. In that mode, I get 44-47 frames recorded at 2520x1080 resolution at 12 bit lossless and the maximum frame rate of 36,572 fps.
4) As seen in previous builds, the shutter speed cannot be invreased above 1/50-th of a sec. This causes screen flicker which makes recording impossible.
5) In an attempt to increase recording time at 42 and 30 fps, I tried the "Frozen LV" preview function. Unfortunately, this preview is broken, error messages run all over the screen during recording and I get corrupt frames.
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I hope, it will be possible to iron out the above problems, so users can benefit from the full potential of the fantastic overclocking feature on the 100D and the other cameras that support it.
