Slashdot Mirror
A Memory Card Torture Test
An anonymous reader writes "Would you buy a Ferrari and put regular gas into it? I don't think so. So why are most of us buying expensive digital cameras and using cheap memory cards? If you want to find out how much better a high speed memory card is, check out this group test of high capacity compact flash and SD cards."
If you take 10,000 photos between taking a "once-in-a-lifetime" photo and backing it up onto a tougher media, you pretty much deserve to lose all your work. The biggest loss of digital camera images are caused by loss/theft of the camera, and user error (accidental deletion). Media failure doesn't even register on the scale.
Athletic Scholarships to universities make as much sense as academic scholarships to sports teams.
What blows my mind in this issue is not the memory cards, but the cameras themselves. A friend of mine just bought a new Canon camera. Sorry I don't recall the model, but it was the newest 8 megapixel SLR they had. Nice camera, he paid a lot for it too. It takes full motion movies. He took my advice and got a 1gb card for it. So we take a few movies and some pictures and plug the camera into their new iMac. And wait. and wait. and wait some more. My god, why is this going so slow? It's been 10 minutes and it's not even 10% done!
The computer shows the camera is hanging off the USB FS (full speed, 12mbps) bus. Why? Is there a problem with the computer? Get out the manual for the camera. Oh.. my.. god... the camera is USB full speed, not high speed. (this is a difference between 12 mbps and 480 mbps for USB cable download speed!) I had to look in several places to confirm the horror. What were they thinking? This camera takes 200mb movies. That takes HOURS at that speed to download.
So we shuttle back down to the camera store and bought him a nice firewire card reader. Back home, we dump then entire card in 10 minutes, movies and pictures included.
This is inconvenient but gets the job done. There is simply no excuse to pay thousands for a camera that takes movies, and have the manufacturers shave a little off the price of manufacturing by substituting a slow USB chip in the camera. And that's all it is, one teeny little chip they just picked the slow one over the fast one. (they are functionally interchangeable, there is no need to redesign the camera) At the bulk they buy chips that can't have saved them more than a dollar per unit.
I have owned two Canon cameras myself and then there is this one. They have performed very well in all cases as excellent digital cameras. But incidents like this make me seriously consider changing brands. If that would have been my camera purchase, it would have gone right back to the store where it came from. Go to store, go directly to store, do not pass go, do not collect $200.
I work for the Department of Redundancy Department.
I was interested in checking out this review, then i saw i would have to page through 20 pages of, well, pages, to make sure i hit their quoat of ads. No thanks, ill read up on fast memory at somone elses site.
Yes, i am aware that half the pages on the internet are like this, and i am also aware that the website owners need to make money. I dont care.
All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
I have an expensive ($800) Digital Rebel XT 8MP camera. It doen't matter how slow of a card I put in it, it works great. It has it's own high speed cache to store like 8 pictures or so depending on settings, and write to the card seconds later. I can easily take a few shots a second, but, it's rare I need to shoot that. While some high end cameras have the write to card weakness, it's certainly not universal among the Ferrari Cameras. Those of you driving around in old yugos might need every bit of speed increase that you can get, you're better off getting a better camera though IMHO.
-- these are only opinions and they might not be mine.
Probably not in America. Everything at a filling pump is assumed to be of a certain quality over here in the UK.
Erm.... Just about all petrol companies offer different octanes. Standard unleaded in the UK is 95 octane, which is a lot higher than the US I think. BP offer "ultimate", which is 97, Shell offer a 98, and Tesco offer a 99. Most others offer higher than standard octane too - where do you buy petrol?
OT - As an aside to those in the US, it's horribly expensive, £1 per litre, which is about $7 a US gallon if my maths is correct. To fill up my car costs well over the equivalent of $100.
Of course you fail to mention that your country is also
:-)
a) lot smaller
b) Not trading in USD
c) Full of weird as small cars [not a bad thing though].
I mean for me to drive home to my folks place is equivalent to [roughly] driving entirely from one end of England to the other. And I don't even leave the province I'm in to do my trip!!! Talk to me when you live in a country that is 3000Km wide about the price of gas.
That and yeah, if oil wasn't traded in USD you'd probably have an easier time buying gas. Of course the next logical choice is the euro, not the pound. So you're still fucked.
Tom
Someday, I'll have a real sig.
There are a lot of different aspects to testing nand flash performance. The burst speed of a 25MHz 4-bit bus (used in original SD) would be about 12.5Mbytes/sec. But data is not written immediately to flash, but stored in a buffer. An often quoted read/write speed of 9Mbyte/sec likely involves writes to consecutively addressed blocks and the SD memory block management system has a ready supply of erased blocks. Put a filesystem on top of the NAND memory block management system, and things get more complex. Fragmentation is going to be a problem here eventually as well. Did this test do any long term testing? Another factor (for PC testing) is the SD interface. Is this over USB or and SD slot such as those found in a laptop. The peak rate may be 60Mbyte/sec, but add protocol overhead, and again, random access times can be heavily affected. I went through this a little while ago and wrote a test program which measures peak USB flash memory performance 'under' the filesystem to as to try to attain the quoted peak speeds. I have write and read results for plain blue Sandisk (5 and 8 MByte/sec) and Lexar (5 and 4 MByte/sec) at http://s3u.sf.net/
Precisely. I was vaguely interested in the article - will a more expensive card improve the shooting speed on my camera? I wondered, or more precisely - would it reduce the delay between being able to take pictures?
Page 2 of the article: "many of our digital cameras have limited write speeds too, so the full potential of these so-called high-speed cards will be restricted.".
So nothing to see here, move along.