AndyH wrote:
That's raises an interesting question. Does the buffer fill "faster" with RAW data or processing of JPEGs?
The only experiments I've made have been in shooting my grandkids' sports, but in those cases, I get many more shots if I'm just shooting JPEG before the buffer fills up. The RAW shots must, I imagine, contain more data, but this seems to be the case for my gear even when I'm shooting fine JPEGs. I normally shoot everything in RAW, but for this particular use, I've found that the buffer accommodates more in JPEGs, so I wonder if the in-camera processing is a factor at all? Never really thought about it much, but my empirical results seem to indicate that processing the RAW data is what fills the buffer fastest. I'll experiment when I'm in a place to do so.
Thanks for raising the question! It may turn out that I've been buying faster cards than I need.
Andy
That's raises an interesting question. Does the bu... (
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Raw data of course fills the buffer faster because the size is much larger then a jpg. A jpg file is created from the raw data, what is not used is thrown away. A 25 mb raw file may end up as a 6k jpg, so it would take many jpgs to equal 1 raw file.
Raw files are not processed in the camera, jpgs are. The camera always takes raw data, if you are recording jpg files then the camera process the raw data per the settings you have set the camera for and only writes the resulting jpg data to the card, the raw data is thrown away.
If you shoot raw, the data is simply written to the card, no processing is done, except of course to add EXIF data.
The camera is capable of shooting in burst mode at specific frames per second and either writing the raw data to the card, or processing the raw data into a jpg and writing the jpg to the card. Depending on the camera, it may be faster to write raw data then to process it into a jpg which then gets written to the card, but of course the raw data is much bigger than the resulting jpg, so in reality shooting jpg and processing the raw into a jpg results in faster burst mode shooting and writing to the card.
Regardless, use of the fastest card your camera can use (write speed) is important. Using slower cards simply reduces how fast the buffer empties which affects frames per second of continuous burst shooting.
Think of the camera buffer as an additional SD card inside the camera, a faster but much smaller SD card. As you take pictures they first go into the buffer, then are written to the SD card...so smaller files means that the buffer can hold more before writing to the SD card and removing the files from the buffer.
FWIW - if I recall, testing my D7100 with the Samsung pro cards, shooting in small jpg, the buffer never filled up, change to raw and the buffer filled after 8 or 9 shots, slowing down the actual frames per second from 6 down to about 3.