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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."
The Rob Galbraith DPI website has a huge database of performance with various cards and various cameras. I use this as a benchmark for deciding when I need a new CF card vs. the Camera I have, and the family of camera I'd love to upgrade too one day.
As a rock-in-roll Physicist once said, No matter where you go, there you are.
"You can't put regular gas in a Ferrari?" No, most high end cars require preimium gas.
"What's the difference between regular gas and this special stuff?" Premium gas has a higher octane number which prevents pre-detonation, aka "knock", which allows high performance engines to operate at higher compression ratios.
" Does that mean when you buy a Ferrari you spend half you life looking for Ferrari-approved filling stations?" No, most every gas station I have been to in my life sells "regular", "silver", and "premium" gas. Have you never bought gas before?
More of a high end performance test.
There was one proper torture test done by the UK Digital Camera Shopper magazine where they dipped in cola, run through a washing machine, dunked in coffee, trampled and then for sport hit with a sledgehammer and then nailed to a tree. They didn't survive the last two tests though...
Wonderfully resilient stuff I'd say.
Couldn't find the article freely availabe on the mag, just a ref at BBC news: http://news.bbc.co.uk/2/hi/technology/3939333.stm
You'd think cards developed to the same spec would have equal performance. Is that really not the case with SD or others? Interesting article.
I don't know about SD cards, but CF cards are compatible as IDE devices, which itself has various specs with varying performance. Various PIO and DMA modes, etc. This would be like comparing hard drives and then saying, "You'd think drives developed to the same spec would have equal performance".
Some cards are built using high density, low speed, low durability CF, while others go for lower density, high speed, high durability CF and multiples of them in one card. Some newer fast cards employ DMA modes over PIO. Also don't forget, the spec itself is not always the bottleneck, so individual models can vary in performance up to the limit of the particular spec used.
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
Like the spec that says a car has four wheels and steering wheel, yet the performance of a Ferrari is markedly different than that of a Geo?
Most of the specs define physical and electrical characteristics, the speed and performance is somewhat abstracted, the device will tell you when it's done, or when it want more data, and can do so in it's own sweet time.
You pay for performance. The higher performing silicon is available in smaller quantities, and commands a premium. Either because the die operates at the higher end of the bell curve and is bined as faster, or is tested more throughly and vigorously.
Most of the specs define physical and electrical characteristics, the speed and performance is somewhat abstracted, the device will tell you when it's done, or when it want more data, and can do so in it's own sweet time.
Interface specs usually do define signal rates and word size (for parrallel). So specs usually do define a top speed. Certainly in the case of CF.
(Of course serial interfaces also define word sizes and sometimes allow for various sizes, however that typically does not change the bits/second rate by much, if at all, depending on the spec.)
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
You're probably talking about the S3 or S2 as no SLR will do movies as the mirror would have to bounce up and down 24 times a second.
Regardless of which one your friend has it seems to be that the Mac is not correctly identifying it as both the S2 and S3 are USB 2.0 capable. (As are the actual SLR cameras that Canon has).
$.02
Actually, the European and American methods of measuring octane are a little different. The end result is about the same for what you put in the engine.
Europe uses RON, the US uses CLC (RON+MON)/2.
I don't read AC A human right
Some specs allow for variation in performance. For example, if the raw performance of the memory cells is expected to increase significantly, the spec will be designed to allow for the highest speed expected to ever be achieved (or the highest speed economically feasible), but to allow devices to negotiate a slower speed by doing things such as inserting delays. i.e. the spec defines compatibility and not performance, AS LONG as performance can be negotiated to be the lowest common denominator of two devices.
I have heard stories of some of the highest speed cards breaking in older readers, perhaps the autonegotiation was designed with the assumption that cards would always be slower than a reader's capabilities, or those readers aren't fully meeting the specification and no one noticed.
retrorocket.o not found, launch anyway?
the newest 8 megapixel SLR they had... It takes full motion movies.
Stop right there... none of Canon's SLRs can take movies. The burst shooting mode has been used to make sort of stop-motion movies, but that's not full motion by any stretch of the imagination. Also, all of Canon's current SLR line has hi-speed USB.
So what camera are you talking about, anyway, since it's obviously not a Canon dSLR?
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
You can't put regular gas in a Ferrari? What's the difference between regular gas and this special stuff? Does that mean when you buy a Ferrari you spend half you life looking for Ferrari-approved filling stations?
Someone (with a lot of money) bought one of Schumacher's old F1 cars and yes, it was contractually required that the car only be run on a specific brand of fuel.
The article summary is pretty oblivious though- you run the octane your car requires, 95% of the time. Gasolene companies love to make you think that filling up your low-compression engine (that requires 89) with 94 octane will make it faster, or "clean" it more. All grades of gas from the same brand have the same level of detergents, generally...furthermore, each kind of detergent is good at removing certain deposits but leaves others, so you're actually best off rotating which brand you fill up with. If you're obsessed about it, just pop in a bottle of Techron cleaner one tank before your next oil-change; it's the stuff BMW, Audi, and others recommend, though they'll charge you a lot more for Techron in a BMW or Audi bottle.) Also, most gas is delivered from port by a distributor that slosh-mixes in a bottle of stuff that "makes" the gas Exxon, Shell, Hess, BP, whatever. When a supertanker crosses the ocean, it doesn't have a "Shell" crude compartment and a "Exxon" crude compartment, etc. It's all the same stuff, a commodity...even though Shell likes to run commercials saying their gas meets manufacturer standards blah blah blah. EVERYONE's gas does, because EVERYONE's gas comes from the same damn crude, gets refined at the same places, and distributed by the same companies.
This is similar kind of "inadequacy" based BS. High end digital cameras have large buffers in part because flash memory is so effing slow; a Nikon D70 has enough buffer for something like 40 full resolution JPEG shots! Running a slow memory card in them won't harm them, damage them, etc etc. There are other factors to consider as well- my canon 10D has a 9 shot buffer for RAW shots, and some sort of in-between buffer for writing them to the card. I used to hit the end of the buffer all the time, because I never noticed that it wouldn't process the buffer while the shutter was held half-down in the focus position. Talk about a design flaw- but knowing that, I kept my finger off the shutter button whenever possible if the buffer had anything in it (displayed in the viewfinder) and the problem disappeared.
As someone who has shot with a semi-pro dSLR for more than two years, I can summarize that article in one sentence: "if you need to shoot images as fast as possible and have a camera with a limited buffer, buy the fastest card within reason, only if Rob Galbraith's tests show it'll make a substantial difference. Otherwise, buy a reasonably heard-of brand with a decent warranty in case it stops working." Why? Because just like with the gas, under the label you'll often find exactly the same thing- and only a very small number of people actually NEED the extra speed of a card that costs 50%+ more.
Oh, last piece of advice: don't buy huge memory cards. Three reasons: 1)you pay more per MB, usually. 2)You put all your eggs in one basket- if you drop a card and step on it, accidentally hit "erase all", or loose it... you get the idea. 3)"Photo tanks" with laptop hard drives offer MUCH cheaper $/GB storage. You could shoot 2,3,4,5GB/day in RAWs on a big vacation and still not fill the smallest of these widgets after a week. Buying one without a drive and putting in the old laptop drive you've got hanging around from an upgrade (provided it's not too power-hungry) is the way to go, as even 30-40GB is a BOATLOAD of space for digital photos.
Oh, and should you be on a trip- bring a few DVD-Rs, and burn the files to one or two if you really want to have the photos. Laptops get stolen/dropped/lost/seized/whatevered, and you can be absent minded / mistake-prone about transferring photos after a week of fun in the sun (aka rm -rf * type mistakes). Put one set in your suitcase, another set in your SO's/friend's/etc.
Please help metamoderate.
My maths may be off, but that means your car gets 25 mpg. When that answer appeared on my calculator, I literally laughed out loud. In the UK we'd refer to that as rubbish efficiency (trends for ludicrous urban SUV usage notwithstanding). 15 years ago I had an ancient piece of crap Morris Minor that did 35+ mpg, ffs.
14 mpg?! Holy crap. What is it, a Chieftain tank?!
Never mind game console standby power usage, get your car manufacturers to sort out their fuel efficiency. If you had to pay UK prices at the pump, I'm guessing that might accelerate the process :-)
Of course, in the UK, the cost of petrol is largely taxation. It's something like 75% of the price, which usually gets people going.
There are different methods for rating octane. RON, MON and (RON+MON)/2 are the major ones. I think the UK uses RON and I know the US uses (RON+MON)/2. RON is always a larger number than MON for the same fuel.
Another US vs World rating issue is stereo amplifier power. In the US we rate in RMS (Root Mean Squared) or more simply, average power output. In much of the rest of the world they rate in peak power. In PP a stereo might be rated as 200W but in the US that same stereo could perhaps only be rated as 60W. Both numbers are correct, the stereo CAN produce 200W of output for very brief moments, but it can sustain 60W of output indefinitely. Which is more accurate? Up to you to decide.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Really, how can you have a roundup of CF cards without any from SanDisk? They're only what, the biggest company in that market? And they just released a new line of CF cards that they're touting as "the world's fastest cards" so this would have been a good time to see how good the performance of their products really is. Maybe instead of picking four random CF cards, Trusted Reviews should have just stuck to the SD card side of things this review, and then they could have done a more comprehensive CF card review in a future article. That way, they could have hit people with twice as many ads.
I know the Canon line-up pretty well, they have three 8mpx DSLRs - 350D (Rebel XT); 20D (discontinued); 30D - and all of them have USB 2.0, none of them does more than 5fps. The last camera I can think of that might not have had USB 2.0 was the 1Ds or 1Ds MkII - it had firewire instead.
Sandisk just announced their Extreme IV cards a couple days ago. They're going to be a little pricey for a while though... http://www.dpreview.com/news/0607/06071906sandiske xtremeiv.asp
Full Speed USB is 12 Mbps and still technically USB 2.0. So just because something says USB 2.0 it doesn't mean it's capable of doing more than 12Mbps
I currently have two CFcards for my camera, a cheapie that came free with the camera & a SanDisk Ultra II. The SanDisk Ultra II was about twice the price of the cheapie memory, but it'll also write about twice as fast. The Extreme III, however, is what SanDisk are currently pushing as their fastest highest-tech card for your camera, and loads of people buy it. Check the table, however, and you'll see it's only a couple of percent faster in my camera... and at twice the price, of course.
So this is why the Rob Galbraith tables are more useful than some 19-page review full of ads - you can just glance down the page & easily compare the brands that your supplier offers for a real-world comparison and see if they're worth the price.
Stroller.
Another (and I think better) comparison site is here and it has also compares different cameras in conjuction with different cards, which is fantastic if you have one of those cameras. Even if you don't, you can tell whether the card is fast.
Not quite. My Canon EOS-1D Mark II has the current firmware, which is from October 2005. I bought a pqi 4GB SD card Hi-Speed 150 card and lo, the camera would not format the thing. Before I took it back to the store I popped it into the PC and formatted it there. Put it back in the camera and it has been working fine ever since. Perhaps they should have picked a different example.
How the fuck did the parent get moderated informative?
1-Higher octane fuel will not increase carbon buildup.
2-As a car gets older, it does not need higher octane fuel. The idea that even a severe case of combustion-chamber carbon buildup could cause a measurable increase in compression ratio is silly. As a car ages, its compression ratio tends to decrease due to ring blow-by, and carbon buildup preventing the valves from sealing well.
3-Higher performance cars often need higher octane fuel because they run at a higher compression ratio, run hotter, and therefore have an increased likelihood of pre-ignition.
4-If you car was designed for 87 octane, and it is knocking during acceleration, that is NOT good, and is often a sign of a timing issue you should fix, not mask with higher octane fuel.
Even occasional knocking during heavy load conditions is bad, as it can cause damage to the engine. Fuel pre-ignition not only causes waste heat (leading into the cycle of more pre-ignition), but the shock of pre-ignition on a rising piston can cause a great deal of damage if allowed to continue for very long, which is (one of the reasons) why many modern cars have knock detectors, and retard the timing if it is detected.
I dub thee... Sir Phobos, Knight of Mars, Beater of Ass.
Of course, in the UK, the cost of petrol is largely taxation. It's something like 75% of the price, which usually gets people going.
Taxation is actually around 66 pence a litre now IIRC - it's just hitting the 2/3rd mark, 67%. It used to be a higher percentage, but then the price of oil went up.
My maths may be off, but that means your car gets 25 mpg. When that answer appeared on my calculator, I literally laughed out loud. In the UK we'd refer to that as rubbish efficiency (trends for ludicrous urban SUV usage notwithstanding). 15 years ago I had an ancient piece of crap Morris Minor [wikipedia.org] that did 35+ mpg, ffs.
A UK Gallon & a US Gallon are different.
A UK Gallon is 1.2 * US Gallon.
You are getting 35 MPG(UK) is the same as 29 MPG(US).
Still the Morris minor seems more efficient
No circles East/West
No Circles North/South
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Exactly.
Externally, newer high speed CF cards support PIO mode 3 which supports around 11MB/s (iirc). Since the external interface is much faster than the numbers they publish (the highet read speed being 8.1MB/s) we have to conclude that the limitation is on the other side of the memory controller. The limiting factor in the future will be what modes your camera and reader support, assuming you intend to use these huge flash drives in a camera. My 20D wants one. I heard it say so.
Constitutional rights may be respected, repealed, or modified; but they must never be ignored.
Exactly. And people would be wise to remember that. Take the whole USB vs 1394 arguments that come up from time to time. Some people insist that since high speed USB 2.0 runs at 480Mbps versus Firewire's 400Mbps, USB is *obviously* faster. Nevermind the fact that 480/400 are signalling rates that have absolutely nothing to do with throughput. Speaking as a USB developer, the spec just says that when a host or device sends a 512 byte USB packet, it goes down the wire at a speedy 480Mbps.
But the spec doesn't care how often you send one of those speedy packets. So in reality, going thru the whole MS disk and USB stacks, you're looking at *maybe* 200Mbps of actual throughput.
Hell, the fastest USB device I ever saw was a piece of hardware that did nothing but consume data as fast as its little memory bus could run with a driver that sent the biggest payloads as fast as it could and it crapped out at 320Mbps (limited by the PC).
Remember: higher signalling rates don't always lead to higher throughput!