Fast CF cards

Don't get x and mb/s confused. 60mb/s is the equivalent of 400x. I use a 16GB Sandisk Extreme in my 1DIV and rarely have to wait on the buffer to clear.

The 200x Kodaks you've found are no faster than your current cards

Neil
 
da_nige said:
Don't get x and mb/s confused. 60mb/s is the equivalent of 400x. I use a 16GB Sandisk Extreme in my 1DIV and rarely have to wait on the buffer to clear.

The 200x Kodaks you've found are no faster than your current cards

Neil
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Thanks Neil, I didn't know that.

Therefore 60 mb/s should solve my problems as my current cards are 15 mb/s and 30 mb/s
 
The Lexar 8GB 600x Professional UDMA Compact Flash, are 90mb sec, write time, only available in 8GB upwards to 32GB
 
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Gary.D said:
Therefore 60 mb/s should solve my problems as my current cards are 15 mb/s and 30 mb/s
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That all depends on what your problems are. The speed at which the camera writes to the card, or the speed at which images move from the card to the computer.

If it's the former then a faster card will make zero difference. The 5D can only write at a paltry 7.5 MB/s. Your current cards are already 2 - 4x faster than necessary.

If it's the latter then you'll need to be using something other than USB2 to transfer the data - because that will limit you to around 30 MB/s. Expresscard, Firewire 800, eSATA or USB3 are required to get an increase in speed.
 
There's also the Lexar PRO 400x UDMA CF cards - I use their 4gb & 8gb versions of it ...

:thinking: Amazon have them in 4gb for £34.99...
 
hollis_f said:
If it's the former then a faster card will make zero difference. The 5D can only write at a paltry 7.5 MB/s. Your current cards are already 2 - 4x faster than necessary.
Click to expand...

But does it not empty the buffer quicker, allowing for more shots to be taken as with the Lexar
 
As Dave says, it's not the in camera write speed for a single image that matters but how fast a card can empty the buffer.

If your only taking 1 shot every ten minuets, the very slowest card will be fine, but if your shooting at a high frame rate or doing HD movies you'll want a fast card to empty that camera buffer.

Most manufacturers now do x600 cards, but I could not find any at less than 8GB.
Personally I have stopped buying Sandisk or Lexar and now use a Transcend x600 16GB card as my first choice. The same speed and quality as the others but at a cheaper price. They don't give you a little card pouch like Sandisk (who ever use them anyway) and they use a lot less packaging than Lexar, but the actual cards work just the same.

Do you need x600, well on a 5d I doubt it (the frame rate is just not high enough) but if you have the right card reader it will help in the transfer to computer (I use a Lexar Firewire 800 reader and you really can see the difference when using a fast card.)
 
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whiteflyer said:
As Dave says, it's not the in camera write speed for a single image that matters but how fast a card can empty the buffer.
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And the speed at which the buffer is emptied relies on the slower of the card speed and the camera speed. It's no good having a fast card if the camera can't write that fast.

whiteflyer said:
If your only taking 1 shot every ten minuets, the very slowest card will be fine, but if your shooting at a high frame rate or doing HD movies you'll want a fast card to empty that camera buffer.
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A fast card will make zero difference with a 5D because it can't empty the buffer faster than 7.5 MB/s.

Oh, and HD video requires nothing more than 8 MB/s.
 
hollis_f said:
No, it doesn't. 7.5 MB/s is the fastest it can empty the buffer.
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Cheers Frank

Just been reading that with a fast UDMA card like the Lexar Pro 600X, the Canon 7D maxes out at a write speed of just under 53 MB/sec:

using an Sandisk Extreme IV card, with UDMA, capable of a write speed of 45 MB/sec:

Please can you explain the difference as to why one writes faster than the other, In the Canon 7D?, as I dont understand it, if you say "No it doesnt", TIA
 
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I've just seen that I'd forgotten the link to Rob Galbaith's site where the 5D speed numbers were obtained. Here it is - LINK.

Rob measured the time it took to write 20 jpegs or 7 raws to the card.
 
Just Dave said:
Please can you explain the difference as to why one writes faster than the other, In the Canon 7D?, as I dont understand it, if you say "No it doesnt", TIA
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Sorry Dave, I'm not exactly sure what your question is. If it's "Why does one card write faster than another" it'll be because of the internal circuitry of the card - some memory chips can handle faster read/write speeds than others.
 
hollis_f said:
Sorry Dave, I'm not exactly sure what your question is. If it's "Why does one card write faster than another" it'll be because of the internal circuitry of the card - some memory chips can handle faster read/write speeds than others.
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MM not sure myself you say it doesnt matter if the card is faster or not the camera can only write at a certain speed, I understand that some cards are able to handle the faster data rate
 
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Your right Frank, I forgot the 5D came out before the new faster UDMA cards.

There must be a date / camera model from which would benefit the new cards.

I know the 1D IV does and Dave's 7D, so I guess we need a list :) :)
 
Just Dave said:
Although Im more interested in the 7D, maybe hes done a test for that as well :thumbs:
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Unfortunately, I don't think he has. I've done some speed tests myself - LINK - which showed virtually zero difference between Sandisk's 45 MB/s and 60 MB/s cards while an ancient 1.5 MB/s dinosaur didn't perform so well. If you examine the second image you can clearly see the effect that write speed of the card has.

Just Dave said:
MM not sure myself you say it doesnt matter if the card is faster or not the camera can only write at a certain speed, I understand that some cards are able to handle the faster data rate
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Yes, some cards can handle faster speeds, but that's only relevant if whatever is supplying them with the data can produce it that quickly. Here's an analogy:

In the days when we had secretaries they could take dictation at around 100 words per minute. But that speed was never reached, because I couldn't speak that fast and remain clear. Although the secretary had a maximum write speed of 100 wpm the whole system was limited by the speed at which I could process the data in my brain into words.

In the same way, if you stick a 100 MB/s card into a camera it can only accept the data as fast as the camera can supply it. The 5D is a mumbling, stumbling slowcoach that can only deliver at 7.5 MB/s while the 7D is a clearly annunciating speed demon that can whack out at least 50 MB/s.
 
Thanks Frank

Pretty much what I thought then, the faster cards will be of benefit to me, thanks for the explanation it made it all clear LOL
 
Cheers for starting of this thread Gary.
Just bought a 5D 1 and was about to buy some fast cards for it. Looks like I could save a few pennies now and go a bit slower.

Good luck with your Card choice!
 
Ive just bought a 500d what sort of sdhc card would be suitable. Do I need a class 10 or will the extra money be wasted?

Ben
 
benj1867 said:
Ive just bought a 500d what sort of sdhc card would be suitable. Do I need a class 10 or will the extra money be wasted?

Ben
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Ive been using Class 6 since I got the camera 18mths ago. I think Class 6 was the fastest at that moment in time. I've have no problems with continuous shooting or video.

It won't make any difference to camera performance as described by Frank if the camera itself can only 'write' at a maximum speed which is slower than the card itself.

If you are only gonna save a couple of quid....I'd just get the Class 10.
 
Can a class 6 card handle the highest write speed possible on a 500d? I'm going to view AF1 on the 26th so I'll prob be taking a lot of shots on continual shoot
 
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