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fgreenhut
08-13-2004, 04:18 PM
When people speak of the speed of cards , like Sandisk CD cards and the like,
are they referring to speed while taking pictures or when transferring from the card to a card reader or computer?

Fred

kgosden
08-13-2004, 09:14 PM
When people speak of the speed of cards , like Sandisk CD cards and the like,
are they referring to speed while taking pictures or when transferring from the card to a card reader or computer?

Actually neither. The speed referenced by most manufacturers is relative to the lowest speed data transfer of a given type of media (SD, CF, etc.) in some 'standardized' test' platform. Yes, this is probably a PC, but it might well be optimized for this purpose and could be nothing like your own home PC. Some types of media do have defined minimum data transfer capabilities in their standards; I believe that SD falls into this category.

Of course, there are actually differences in design approaches that make the speeds more or less important. In CF cards the I/O controller is embedded in the card itself. SD and SM cards are just memory and the controller is required to be in the device (camera, PC, etc.). Generally this would mean that CF cards should show greater differences with their speed ratings than would SD cards. But there are so many other factor that this is not clear cut. Does your camera or PC processor have enough internal speed to use the extra speed? Is there a high speed RAM buffer between your CPU and the card? How fast if the internal data transfer of the device itself?

So while faster is generally better do not expect to see a substantial difference in most devices.

fgreenhut
08-14-2004, 04:45 AM
All that was a bit over my newbie head. Let me ask a more simple question. What is the advantage in going to a more expensive card (ie: Ultra) ?

kgosden
08-14-2004, 07:52 PM
The main advantage is that the card manufacturer and retailer make more money. Unless you have a fairly high end prosumer camera you will probably not notice any difference in card speeds. That said, some of the cards, like the Ultra series from Sandisk are supposed to be a bit higher quality with more error free read/write cycles. Cameras that can take advantage of faster cards tend to be in the $750 and up price range.

D70FAN
08-14-2004, 09:22 PM
The main advantage is that the card manufacturer and retailer make more money. Unless you have a fairly high end prosumer camera you will probably not notice any difference in card speeds. That said, some of the cards, like the Ultra series from Sandisk are supposed to be a bit higher quality with more error free read/write cycles. Cameras that can take advantage of faster cards tend to be in the $750 and up price range.

Actually, for consumer digicams, Ken is correct. Even many digital SLR Pro cameras don't take advantage of faster buffer to flash-card transfer speeds.

The only advantage to fast cards, in consumer applications, is in the download speed which requires a USB 2.0/firewire reader and computer equiped with USB 2.0/firewire.

You may find this interesting reading:

http://www.robgalbraith.com/bins/multi_page.asp?cid=6007

The cameras listed are those that have a fast enough processor to take advantage of faster memory. If your camera is not on this list, it probably can't take much advantage of faster (and more expensive) flash memory cards.

I have a D70 which can take great advantage of fast flash, but I have 3 "normal" cards (because they are cheaper) and one Ultra II to use when I need high speed continuous shooting (like sports events or trying to capture lightning strikes).

In most cases the average camera user does not need high speed memory, even to increase workflow.

fgreenhut
08-15-2004, 05:37 AM
Thank you Ken and George. Especially for the url to the article. I am a whole lot smarter than I was before joining this forum.

singhal2
08-19-2004, 10:58 AM
hi all,this is my first post here and hope to be fairly active.....let me introduce myself first,i am a doctor by profession and have been a film guy so far (canon rebelx),it has taken me sometime to get convinced that digital photography is indeed good(couldn't believe that a chip could give superior pics than a film)so have decide to get a digicam,in the course of my research i find people talk about write speeds on memory cards,various types of storage devices on digicams,can someone explain to me the differences between the various cards that digicams use or post a link to that effect.

i am a frequent visitor to one of my fav hometheater sites...audioholics.com and the lay out of dcresource forums is like audioholics,so am feeling quite at home here !!!!
thanks in advance

singhal2

John_Reed
08-19-2004, 11:40 AM
The only advantage to fast cards, in consumer applications, is in the download speed which requires a USB 2.0/firewire reader and computer equiped with USB 2.0/firewire...In most cases the average camera user does not need high speed memory, even to increase workflow.How many examples do you need to prove that "lower-end" cameras also need high-speed? I've already cited the issue on my "low-end" FZ10; it's an issue with movies (at least) for the "low-end" Canon S1, and even the "point and shoot" Nikon 5200 can make good use of a faster card when writing those 5 consecutive shots at 3MB/image. Get with it!

D70FAN
08-19-2004, 12:39 PM
How many examples do you need to prove that "lower-end" cameras also need high-speed? I've already cited the issue on my "low-end" FZ10; it's an issue with movies (at least) for the "low-end" Canon S1, and even the "point and shoot" Nikon 5200 can make good use of a faster card when writing those 5 consecutive shots at 3MB/image. Get with it!

Very good points. I bow to Johns expertise. Since I don't use my camera for movies...

However, I would like to see hard data on the transfer speed difference on any consumer digicam. That may be unfair as even the memory guys don't have that data.

Also we may be discussing apples and oranges, as I doubt seriously that a consumer digicam can use the throughput of an expensive Ultra II or 80X Lexar card any more so than a 20X card. I would agree that a lower cost ~20X might speed things up a little over say 2X. Keep in mind that newer so-called "standard" cards are in the >12X range.

So I think we are looking at high-speed from 2 different perspectives. I am thinking buffer-to-flash transfer of 4-6 MB/s and you are thinking 1 MB/s or less.

In that case your point is well taken.

John_Reed
08-19-2004, 02:54 PM
So I think we are looking at high-speed from 2 different perspectives. I am thinking buffer-to-flash transfer of 4-6 MB/s and you are thinking 1 MB/s or less.George, take the case of the Nikon 5200, which can write out 5 - 3MB images (taken at fine quality) consecutively, the 5 captured at the end of a burst of continuous shooting. (I guess that's their new "BSS" feature?) Would you, the user of a 5200, be happy if that process took 15 seconds? I wouldn't be, I know. Which is what it would take at your hypothetical 1MB/second. Even at 2 or 3 MB/second, it's still a long wait while the camera is frozen out of taking any more shots. Just the difference between shooting a SanDisk "normal" 256M card and a Panasonic High-speed card (I don't know exactly what its "X" is) was enough to make my wife cry out in alarm "It's frozen!" when I handed her my camera with the SanDisk in place, and she shot a series of burst shots, requiring the camera to write out 5X1.5M = 7.5M after the burst before it came back to life. The same sequence takes about 2 seconds for the Panasonic, and about 10 seconds for the SanDisk. For the user who's trying to follow some action, that's a big difference, believe me!

Janet
08-28-2004, 06:36 AM
I am probably going to be buying a Panasonic FZ 15 or 20 depending on the reviews. What card, brand, etc., should I buy to go with it? Are they trustworthy enough to buy a big card to store my photos when traveling, w/o a way to download, or should I buy a couple of different smaller ones?

Where do you guys store your extra ones so they don't get lost or misplaced? I know, I misplaced my whole camera! but I worry about losing things as small as the storage disks! I guess I answered my own question. Better to have more disks as while traveling, cameras do get stolen and if all pictures were on the same card, then all pictures would be gone. But what do you guys do?

And, is it still OK to have the camera go through the scanners at the airport, or should it be hand inspected?

Thanks,
Janet

erichlund
08-28-2004, 11:51 AM
I'm not familiar with that type of camera. My cameras have all used CF cards. I don't do this professionally, so I don't worry too much about losing a money shot. For me, I have a Lexar 1GB 80x in a Nikon D70. At the end of the day, I store my photos. I did have a problem of corrupted photos with a SanDisk 192MB card (that I originally got with my Nikon Coolpix 990), but that went away by just reformatting the card. I keep the 192 and a SanDisk 256 as backups, in case I run out of space on the 1GB card. My wife's 5MP Canon S60 has another SanDisk 256 in it.

If you are a pro, then I would suggest more smaller cards as a safer alternative.

Cheers,
Eric

Janet
08-28-2004, 07:42 PM
Hi Eric
I am certainly not a pro, but I have just had the experiece of losing a digital still camera and most of the digital movies that I took on a long trip through the national parks last summer! I would hate to do that again, not the trips, but lose a camera and film. My next trips will be once in a lifetime to foreign lands and I want to bring all my pictures home with me. I know nothing about storing pictures other than with the use of a computer. I guess there must be something to download them in that is small and portable. I know there was with the CF though I never used one.
Does anyone know what they are an how they work?

Thanks
Janet