Whst is it with camera buffers

[JR1]

Not an issue more a, what the heck is it

Ok I do know but, as we all know you read that you have 100/500/50 shots available in whatever mode you are in, what I have tried to find out is just "what" the buffer capacity is in actual "RAM"

Any ideas of a source of this info eg what "RAM" is in the D7100, D4s etc

I am assuming that the "buffer" is not standard RAM, in fact a lot faster and built into the actual processor chip.

Canon did an upgrade for the firmware to help improve the 7D performance but I have asked Nikon about the D7000/D7100 and they plan no such upgrades, hmmmmm, if one can

Thanks

[RichardTaylor]

I don't worry about it, I just worry how much it big it is before it fills up.
Keep in mind it is not just the physical size of the buffer (which may be treated as a stack, it has been years since I have looked at processor architecture).
It is also how quickly it is written to and how quickly information can be extracted from to the plug in storage etc (which is all happening as you are shooting).
Canon with the 7D probably improved the effecicancy of the code acessing the buffer.

Is there anybody like Magic Lantern for Nikon cameras?

[JR1]

Just curious, I know the relationship between write speeds etc just interested in how the memory is allocated and made up

[pnodrog]

It is unlikely that RAM/buffer speed will be a limiting factor. The speed needs to be sufficient to not slow down the clearing of the image off the sensor but assuming it is static RAM it will be many many times faster than the write speed to whatever card storage is being used so it is the amount of RAM available for image buffering that is of interest. I have a Nikon D800 that will buffer 17 x 41.3MB images about 700MB in total. I assume allowing say 300MB for processing it has a total of about 1GB of RAM

Due to the die sizes required for both the CPU and 1GB of RAM I would be very surprised if they were fabricated onto a single chip.

[RustBeltRaw]

It should be pretty easy to roughly figure out the available buffer size, and its speed. For instance, my 60D shoots roughly 19MB files, 7 shots to a full buffer. Roughly, 7 shots x 19MB = 133MB buffer (in reality, probably 128MB of fairly fast RAM). It can load those 7 shots to a SanDisk Extreme Pro card (max write speed: 90MB/sec) in about six seconds. 128MB / 6sec = 21MB/sec transfer speed. Sanity check: that means unloading the buffer would be bottlenecked by a 10MB/sec SanDisk Ultra card, but not a 45MB/sec SanDisk Extreme card.

The buffer RAM probably isn't built into the processor chip. Cameras across multiple points in the market use the same processor (or even dual processors), and for cost savings, the manufacturer probably prefers to select buffer size independently.

[drjuice]

Dunno about anybody else, but if you've ever looked inside a camera's guts and seen all the various chips in there, it makes a bit of sense to remember that, a particular camera may have an intermediate stage before the image makes it to your actual storage medium. Because my current "big" digital camera is a Sony a700, I use Sony or San Disk Memory Stick ProDuos as my storage media because my computer has a builtin slot for this kind of storage. This medium is a bit pricey, but the important point is that it has literally NEVER failed (crossing my fingers as I type). And, ultimately, the storage medium per se is what matters.

v