In a prior post, A1 CFE-a Memory Card Performance Data, I showed memory card performance data for the Sony A1. This post includes data for four CFE-a memory cards in a Sony A9III for Compressed RAW data. The data and the formatting is similar to the prior post. The methods of making the measurement have been described before so I will not repeat that here.
The first four charts are for the Lexar Gold, Lexar Silver, Delkin Power and Sony Tough cards, all 160GB. You may notice that they are all the same. I found no measurable difference in the cards. This implies that the performance is determined by the camera not the memory cards. It is possible that the cards are all essentially identical except for the branding (same source?), but the the fact that the Lexar Gold and Lexar Silver, which have different specs (and prices), have identical performance supports the idea that it is the camera, not the card, that is determining the performance.
It is interesting to compare the A9III data with the A1 data in the prior post. IMO, the most surprising difference is that the A9III rate is 5 FPS when the buffer is full and the A1 rate is ~10 FPS, even though the A1 files average 54MB and the A9III files average ~25MB. The fifth chart shows the comparison in data rates for the A9III at 120 FPS and 60 FPS, along with the A1 rates for 30 FPS.
The buffer size is 127 frames for the A1 (~6.9GB), and 236 frames for the A9III (~5.9GB). The buffer clears in 11sec for both which is 617MB/sec for the A1 and 530MB/sec for the A9III. I had anticipated the A9III buffer might be larger and clear faster.
The last chart shows the frame intervals. As with the A1, they are not uniform. For example, the frame interval for 120 FPS bounce around among ~4, ~8, and ~12 msec, and they average 8.3 msec. When the frame rate slows to 22 FPS, the frame intervals bounce around among ~8, ~67, and ~78 msec and average 45 msec. There are similar variations in frame intervals for other frame rates.
As was the case for the A1, the performance data is a bit more complex than expected, and the "expert" data provided on various web sites and discussed in many forums is usually inaccurate and incomplete.
I did not make measurements for anything other than compressed RAW. I think that photographers that are concerned about performance are shooting in that mode. If you want to make measurements for a different memory card or data mode, send me a PM and I will try to help with the measurement method and analysis. A1 CFE-a Memory Card Performance Data
In a prior post, A1 CFE-a Memory Card Performance Data, I showed memory card performance data for the Sony A1. This post includes data for four CFE-a memory cards in a Sony A9III for Compressed RAW data. The data and the formatting is similar to the prior post. The methods of making the measurement have been described before so I will not repeat that here.
The first four charts are for the Lexar Gold, Lexar Silver, Delkin Power and Sony Tough cards, all 160GB. You may notice that they are all the same. I found no measurable difference in the cards. This implies that the performance is determined by the camera not the memory cards. It is possible that the cards are all essentially identical except for the branding (same source?), but the the fact that the Lexar Gold and Lexar Silver, which have different specs (and prices), have identical performance supports the idea that it is the camera, not the card, that is determining the performance.
It is interesting to compare the A9III data with the A1 data in the prior post. IMO, the most surprising difference is that the A9III rate is 5 FPS when the buffer is full and the A1 rate is ~10 FPS, even though the A1 files average 54MB and the A9III files average ~25MB. The fifth chart shows the comparison in data rates for the A9III at 120 FPS and 60 FPS, along with the A1 rates for 30 FPS.
The buffer size is 127 frames for the A1 (~6.9GB), and 236 frames for the A9III (~5.9GB). The buffer clears in 11sec for both which is 617MB/sec for the A1 and 530MB/sec for the A9III. I had anticipated the A9III buffer might be larger and clear faster.
The last chart shows the frame intervals. As with the A1, they are not uniform. For example, the frame interval for 120 FPS bounce around among ~4, ~8, and ~12 msec, and they average 8.3 msec. When the frame rate slows to 22 FPS, the frame intervals bounce around among ~8, ~67, and ~78 msec and average 45 msec. There are similar variations in frame intervals for other frame rates.
As was the case for the A1, the performance data is a bit more complex than expected, and the "expert" data provided on various web sites and discussed in many forums is usually inaccurate and incomplete.
I did not make measurements for anything other than compressed RAW. I think that photographers that are concerned about performance are shooting in that mode. If you want to make measurements for a different memory card or data mode, send me a PM and I will try to help with the measurement method and analysis.
May 04, 2024 at 04:11 PM
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