At 10:47 PM 2003.01.16 -0600, you wrote: >Faster cards will make a difference on the 1D. The card does not affect the >buffer capacity, which remains constant relative to the ISO/quality >settings. The 1D will write to the card while you continue >shooting.(Something the D30 and D60 do not do). So, a faster card will catch >up faster. I have 2 Rytek Ridata's. Which are really fast. According to Rob >Galbraith's <http://www.robgalbraith.com/media/compactflash/index.html> >testing the Ryteks are second only to Lexar's 24X (slightly) > >Its pretty tough to run the buffer full on the 1D with a faster card. > >Richard Bajjalieh >mailto:[EMAIL PROTECTED] >M.K.I.A.I. > >The EOS-1D advertises its amazing 8 frames per second >shooting speed but there is no mention in any >literature or technical info about minimum acceptable >performance for the compactflash card in the camera. >Does it make any difference whether you have a Lexar >24x card or some generic unrated card (probably about >4x)? I know the camera has a huge internal buffer. >Does the compactflash speed increase the size of the >burst total from 20 frames to some larger number? > >Thanks, >John Lovda > > Yes card speed does have an overall affect on shooting rate if you exceed the buffer space in the body.
On my 1Ds, using a Sandisk Ultra 512 MB card, once the body's buffer is full, and I keep the shutter button held in 3 frame per second mode, the camera will slow down to about 1 frame every 1.5 seconds if I set quality to "small jpg" format (about 1.4 MB per image) In raw format (at 11.4 MB per image) once the body's buffer is full, the shooting rate slows to about 1 frame ever. 1.5 seconds for 4 frames then slows down to about 1 frame every 4.6 seconds (averaged over 4 frames), I think the CF card is providing some amount of high speed buffering internally for the first few image writes (perhaps a 64 MB buffer) Sandisk indicates their cards are rated at 2.8 MB per second substained writing speed. The small jpg file write rate for my 1Ds appears to be about 1MB per second, so the rate is limited by the camera. At the raw image size, the initial burst rate for the body to card is very quick at 7.6 MB per second, then slows to a rate of 2.5 MB per second or just a bit under the substained rate of the card. Provided you had a very quick card, I think the body can write at something like 8 MB per sec but that would for a card in the order of 50 times the data rate of a CD rom (which a lot of CF cards ref their speed to) The 24x card therefore can provide something in the order of 3.8 MB per second transfer rate (is that substained??? or burst) which should permit the body to write an image every 3 seconds. Edward Agnew * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
