Sunday, 17 February 2008

Update to Canon G9 RAW writing times...

In my earlier posting about my first impressions of the G9 I reported my experience with RAW file write times in single shot mode. I have since repeated the experiments in continuous mode.

The specifications suggest that the G9 ought to be able to reel off 1.5 frames a second in continuous mode with "fixed" focus - which I take to mean manual focus - and 0.7 frames per sec in continuous AF mode. Since I use RAW mode I was interested to see what times I would actually get.

Repeating the tests in both continuous AF and manual focus modes I found that with the Sandisk Extreme III SD card I was getting a shot every 1.5 secs (which is about 0.7 frames per sec), whereas with the much slower Toshiba SD card I was getting a shot at just under every 3 secs. So definitively here the card speed shows up. The faster card was yielding real world times twice that of the slower card.

I did not find any significant speed differences between
continuous AF and manual focus modes for either card, although I did sense that the time between the first and second shot was faster than subsequent shots with the Toshiba card. This would make sense if the buffer is large enough to accommodate a second shot, but that subsequent shot times are governed by card write times.

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