WTB: CF's...a good 5 or 6 gigs.

[Ronald S. Jr.]

Ok, I'd like to get a few CF's for a couple of upcoming weddings...I need at least Ultra II speed...prefer Extreme III. I'd like 2 gig cards if possible. Who's got some?

[alexanderjba]

Amazon.com had them (Sandisk Ultra II 2gb) earlier today for like $90 including shipping. pretty good prices, seemingly prices are dropping like crazy for most all CF cards... Now if only the price would drop on the 10-22mm EF-S...

[Ronald S. Jr.]

Yeah, I just got 4 gigs of Extreme III for about $250 shipped (two 2gig cards). Could still use a couple more, though.

[Mike Panic]

scroll down - tons of deals

if you don't need speed in cards, 4gb for $129 is really hard to beat: http://www.ilikecheapstuff.com/2006/02/sandisk-sdcfb4096a10-4gb-compact-flash_08.html

2gb ultra II: http://www.ilikecheapstuff.com/2006/02/sandisk-2gb-compactflash-ultra-ii-8899.html

what do you need extremes for? you shooting winter sports?

[Ronald S. Jr.]

Nah, I just like the comfort that they keep up with bursts on my 20D and I'll never have to wait. Plus, once in a while, I lose a shot or two for one reason or another, and I have a better chance of getting it back with the III's. Also, I like that they'll copy to my computer twice as quickly as my Ultra II's.

[Mike Panic]

as someone who works in the IT community and the camera industry, i feel pretty comfy telling you that you have an equal chance of recovering an image from any type of CF card, not one over the other.

additionally extreme cards do not copy to your computer at a ratio of 2:1 over ultra II's. your 20d has a frame rate of 5fps with a buffer of around 20 shots, give or take... so thats about all you'll ever need unless you upgrade to a faster body

lastly, the extreme III's are designed for extreme weather, cold / warm / hot and quick changes between them . sandisk pays money to a company to certify them as "extreme", hence the higher price.

having shot w/ lexar 80x, sandisk ultra II and kingston elite pro cards, i have never felt a differnce in real world shooting situations

[In2Photos]

Hey Ronald, someone mentioned B&H had 2GB Ultra II for $89.95.

[Ronald S. Jr.]

Thanks guys. Extreme III's are twice as fast, regardless. If you shoot a burst of 20 RAW shots, that's about 160mb, give or take. If you're using Extreme III's, it will take approx 4-5 seconds after the burst has stopped to finish writing to the card. If you're using Ultra II's, it'll take more than 15 seconds. It's a difference, and I've experienced it first hand.

Of course, this is all on the assumption that I'm not an idiot.

Also, Mike, supposing speed of the computer weren't an issue, wouldn't the Extreme III's have the potential to copy to the computer twice as quickly? After all, the III's have a sustained rate of 20mbps. The II's are only 10.

Anyway, I'm set on these now, so thanks guys. We're done here.

[samdring]

Also, I like that they'll copy to my computer twice as quickly as my Ultra II's.

In same boat so I thought I would test:

43 x 5D RAW files each from 11.3 MB to 13.3 MB totalling 509 MB
Copy to Ultra II 67 Seconds - copy from 57 Seconds
Copy to Extr III 58 Seconds - copy from 55 Seconds

So downloading from card 2 seconds difference per minute!! All tests to and from Internal High Speed USB and to/from RAID 0 HDD.

[Ronald S. Jr.]

Of course "High Speed USB" is what, 6 or 8 mbps, no? I meant if computer speed weren't an issue. The transfer speed of USB 2.0 is lower than the transfer speed of either card.

[Thordic]

Real USB 2.0 high speed is around 60 MBps, theoretically. But theres three speeds of USB 2.0, the other two being much slower.

[kampphoto]

ummm you can't burst shoot 20 RAW images on a 20D... last time I checked it was 6 before having to write... and even then you can only shoot 1 shot for every shot written to the card... 20 JPEG's maybe... and with a Kingston 2GB card it's just as fast writting as the over priced Xtreme cards.

[tommykjensen]

ummm you can't burst shoot 20 RAW images on a 20D... last time I checked it was 6 before having to write... and even then you can only shoot 1 shot for every shot written to the card... 20 JPEG's maybe... and with a Kingston 2GB card it's just as fast writting as the over priced Xtreme cards.

Yes You can. The write from buffer to card is so fast that it takes time before the buffer is full. Thats why speed is so important.

Remember 300D could not write to the card while shooting. 20D can.

[Kraig C]

Extreme III sounds like a good choice.

[kampphoto]

Yes You can. The write from buffer to card is so fast that it takes time before the buffer is full. Thats why speed is so important.

Remember 300D could not write to the card while shooting. 20D can.

Well i guess my 20D is broken cause I just tried to burst 20 RAW shots in a row on an Xtreme III... nope... nice try though...

Right from the 20D spec page on the Canon website -

Drive Modes
Single frame, Continuous, Self-timer
Continuous Shooting Speed
Approx. 5 fps (at 1/250 sec. or faster speeds)
Max. Burst During Continuous Shooting
23 shots (Large/Fine JPEG) or 6 shots (RAW or RAW+JPEG)

look for yourself - http://consumer.usa.canon.com/ir/controller?act=ModelTechSpecsAct&fcategoryid=139&modelid=10464

So 20 raw shots in burst mode... on a 20D... good luck with that. And in regards to what I said about writting to the card while shooting... yes i realize the camera can do both at the same time, but if you are shooting burst mode full out and hoping to get 20 shots while the camera tries to write to the card, it's never going to happen.

[tommykjensen]

Well not 20 in a second. But I can shoot more than 6 before the buffer is full and thats with Ultra II.

I did some tests some time ago shooting continous for 20 seconds. And I could still keep shooting. At no point the camera stopped because the buffer was full.

With 1 GB Ultra II I could shoot 51 jpg's or 20 raws.

The 6 shot limit is the size of the buffer. 20D writes the images fast to the card so it takes a while before the buffer is full.

[Ronald S. Jr.]

I just tried with an Ultra II, and it did 6, and then one every second while it was writing. It continued that for some time, and then started bursting again after several seconds when it caught up.

[tommykjensen]

I just tried with an Ultra II, and it did 6, and then one every second while it was writing. It continued that for some time, and then started bursting again after several seconds when it caught up.

The point is the camera never stopped right? You could shoot a new image all the time? Not with the same speed but at no time You got a busy msg or something because the buffer was full and You could not shoot? And thats what I am saying.

[Ronald S. Jr.]

Oh yeah, even when I let go of the shutter release after a while, I could still shoot while it was writing.

[kampphoto]

ok lets do some simple math on this -

Ultra II - Sustained write speed of 10mb/sec
Average RAW file 8.5 mb
= 1.17 images written per second or 10mb

Assuming you are shooting at a some what standard shutter speed of even 1/250 sec
4 x 8.5mb = 34mb/sec

Canon 20D buffer holds 6 RAW images = 51mb (approx)

So assuming the card can write 10mb/sec from the buffer, to empty the buffer it would take 5 seconds... mean while you are re-filling the buffer at a rate of 34mb/sec

I am failing to see how you can shoot a full 20 shot burst... and it's not like 1/250sec shutter is that fast... 1/5000sec thats an insane comparison, but 1/250... not really.

To have a perfect balance of writting to the card from the buffer to writting to the bufffer you would have to shoot at a shutter rate of like 3/4sec

So even with the Xtreme III which writes at 20mb/sec it's impossible unless you are bursting with a slow shutter.

Thats what I'm saying.

[In2Photos]

ok lets do some simple math on this -

Ultra II - Sustained write speed of 10mb/sec
Average RAW file 8.5 mb
= 1.17 images written per second or 10mb

Assuming you are shooting at a some what standard shutter speed of even 1/250 sec
4 x 8.5mb = 34mb/sec

Canon 20D buffer holds 6 RAW images = 51mb (approx)

So assuming the card can write 10mb/sec from the buffer, to empty the buffer it would take 5 seconds... mean while you are re-filling the buffer at a rate of 34mb/sec

I am failing to see how you can shoot a full 20 shot burst... and it's not like 1/250sec shutter is that fast... 1/5000sec thats an insane comparison, but 1/250... not really.

To have a perfect balance of writting to the card from the buffer to writting to the bufffer you would have to shoot at a shutter rate of like 3/4sec

So even with the Xtreme III which writes at 20mb/sec it's impossible unless you are bursting with a slow shutter.

Thats what I'm saying.

I believe what they are trying to say is that once you reach the 6 RAW in the buffer that the 20D will conitnue to shoot at about one RAW image per second as it writes the images to the card.

[kampphoto]

I'm not arrguing that you can't just hold you finger on the shutter release and eventually fire off 20 straight RAW shots...

The definition of burst mode -

A high-speed transmission mode in a communications or computer channel. Under certain conditions, the system sends a burst of data at higher speed for a limited amount of time. For example, a multiplexor channel may suspend transmitting several streams of data and send one high-speed transmission using the entire bandwidth.

What I am trying to say is you can burst 6 shots and then all of the data must be written before you can burst a full 6 shots again... I'm not saying you can't write data and shoot at the same time. If you burst 6 shots and let say only two write, you're only going to be able to quickly burst two more shots. There is no way you can "burst" 20 shots in a row on the 20D, regardless of the memory card. That is what i'm trying to say.

Think of fireworks... a firework exploding in the sky is a burst... the inital explosion is the burst (6 shots,) the slow buring parts are the continued brun (the next 14 shots at 1/second)

[paishin]

Correct me if I'm wrong but I think this is the market place of the forum....and Ronald just wanted to buy some CF cards.
ahhhh....sales nowadays become more and more thechnichal...

[Jon]

Ronald - if you're still in the market, B&H has the Extreme IIIs for around $99/2GB with code "psjan". Just got 6 GB worth in.

On the buffer question - the 20D has a dual-ported buffer unlike previous Canons. That means it's able to keep writing from the sensor while it's writing to the card. Previous Canons used the same data path to write to and read from the buffer, so whenever you took a new picture it stopped writing to card until the latest pic had been written to buffer. This makes a significant differnece in how fast it can clear the buffer.