aniramca@[EMAIL PROTECTED]
wrote:
[SD cards]
>1. Why do they multiply in the order of
>1,2,4,8,16,32, etc. Why not in nice number like 5, 10, 20, 30, 40, 50
>GB, etc (metric)?
Because the native language of the computers we have today is binary, not
decimal.
BTW: metric is something different.
>2. On the back of my regular SD card, there are approx. 9 contact
>areas which connect into the terminal. Are all those 9 contacts
>currently utilized for a typical usage in a digital camera?
See e.g. http://pinouts.ru/Memory/sdcard_pinout.shtml
>Or perhaps
>that they only use 2-3 contacts and the others are just reserves for
>future use? I noticed similar thing for a telephone jack. There are
>those phone cables with only 2 connection wires inside (cheaper), and
>there are with more wires (which is perhaps capable for faster
>connection or other accessories in a phone - just guessing). Is there
>a technical discussion in the internet about these contacts and/or the
>details inside an SD card?
See http://en.wikipedia.org/wiki/Secure_Digital_card
for a phletora of
more
links.
>3. They said about 32GB SD card. What about the Compact Flash card?
Usually CF is about half a year ahead of the other formats and 32GB CF are
indeed availaible today, although still a bit hard to find.
>What is the largest size available currently for CF? Is CF, xD and
>Sony stick will eventually be abandoned in favour of SD cards? (just
>like the wars of betamax vs VHS, and recently between blue ray and HD
>DVD). I believe that SD card was pioneered by To****ba.
The CF interface which is the same as PCMCIA just in a different form
factor
has too many technical advantages over SD, whereas SD is often more liked
because the cards are smaller and the connectors less fragile. Those two
will be sticking around for a long time. The other formats are too
proprietary and IMO will die slowly just like the other extinct custom
formats.
>4. For an average usage in a digital camera, how useful is a 32 GB
>card? Would you prefer to carry 4x8 GB SD card or one 32GB card?
Please see the previous heated discussions on that topic, no need to beat
a
dead horse all over again.
>the future commercial digital cameras in the market ever reach, say 32
>or 64 MP cameras? I assume current RAW files are now about the size of
>25MB each.
"Predictions are difficult, in particular when they are about the future."
But if history is any indication, then yes, sensor sizes will increase,
although today's cameras already have more resolution than 95% of all
photographers ever need. Just consider, how many people are happy with
those
crappy pictures from cell phones.
>Do professional cameras produce larger size RAW files? I
Please define professional.
Aside of that, the size of a RAW file depends on the size of the sensor
and
if used somewhat on the compression algorithm.
>5. Is the new 32 GB SD card compatible for all current digital
>cameras, regardless of features and prices?
Of course not. The original SD as defined in 2000 is suffering from the
infamous 2GB limit. Therefore after only 6 years the SDA had to create a
new
standard SDHC. See the previously mentioned Wikipedia article, sections
"5.1
Compatibility issues with 2 GB and larger cards" and "6.1 SD and SDHC
compatibility issues" for details.
In addition to that there is also the question if your camera can handle a
file system, that sup****ts more than 2GB or if it is limited to FAT16
only.
>something about High density SDHC usage, and I wonder if my cheap $100
>camera, or my 4 years old camera (3MP) can handle it. Or is this for
>high end cost, latest model, and high MP cameras' usage only?
Cameras before 2006 cannot possibly sup****t SDHC because SDHC wasn't
defined
until then. As for the file system: depends how forward thinking the
firmware designers were and if they included sup****t for other filesystems
beside FAT16.
While file system sup****t is purely a software issue and could be added by
a
firmware update if the manufacturer is inclined to to so, I am not sure
about SDHC. I think SDHC requires new hardware circuits, but I am not
certain.
jue
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