40D CF and image size questions

[kifenzo]

just a few quick quetions about Canon 40D:

how fast 40D saves RAW files?
how much megabites for one RAW and how much for a best quality JPG?

do you recommend using large CF's like 4gb, will it not make the camera performance slower when it gets full?

When buying a CF what would be your specific recommendations for 40d? what speed should i consider? and maybe what brand (if it matters at all).

thank you for your time!

 

[kifenzo]

just got a call that my 40D arrived!! come on guys gimme some input about that CF that i'll buy tommorow to start shooting. pleaaseee

 

[Bob Burasco]

This might help.

Recording Format

DCF 2.0 (Exif 2.21): JPEG, RAW and RAW+JPEG simultaneous recording possible. Multiple options for recording images on a memory card.

Image Format
JPEG, RAW (Canon CR2)

File Size
JPEG/Large: Approx. 3.5MB (3,888 x 2,592)
JPEG/Medium: Approx. 2.1MB (2,816 x 1,880)
JPEG/Small: Approx. 1.2MB (1,936 x 1,288)
RAW: Approx. 12.4MB (3,888 x 2,592)
sRAW: Approx. 7.1MB (1,936 x 1,288)

(from Canon)
Bob B

 

[kifenzo]

thanx Bob and congrats with your new toy!
i wonder why RAW on my panasonic fz-50 was almost 20Mbs...

i want to understand will there be a real difference with 60x card and 133x or such...

 

[Lenny L]

i wonder why RAW on my panasonic fz-50 was almost 20Mbs...

If you look at the specs for a 40D:

10M pixels x 14 bits = 17.5 MB packed. Add black pixels, metadata and the preview JPEG, you can easily imagine it being 20MB. I believe Canon RAW is losslessly compressed. Don't know enough about the Panasonic, but I read somewhere that Nikon NEF is not compressed.

i want to understand will there be a real difference with 60x card
and 133x or such...

The camera will very likely save files to the 133x card (20 MB/s) faster than the 60x (9 MB/s). However, it is probably only slightly faster with the 133x card than the 60x. If the 133x is not much more expensive, I'd suggest getting that instead of the 60x, since file transfer to PC (if you use a good card reader) will be more speedy.

There are 266x / 300x cards out there. However, they achieve that speed through UDMA transfer mode. The 40D doesn't support that mode, so will not take advantage of the blinding speed, but it can use the card. To take full advantage of the speed, you need a card reader that supports UDMA.

 

[Bob Burasco]

Bob B

 

[macshark]

Camera writes the frames to a DRAM buffer first. 40D's buffer can hold about 75 Large/Fine JPEG frames or 17 RAW frames. If you use a really fast flash card, you may be able to get one (or two?) additional frames before the buffer is full as the contents of the buffer will be written somewhat faster to the flash as you are filling the buffer with new frames. After the buffer is full, you may also get a slightly faster burst rate (about 1/sec?) with a faster flash card.

A reasonably fast flash card like the Sandisk Extreme III is good enough for the 40D. If you use a faster card like the Sandisk Extreme IV, you won't see significant performance difference. However, if you use a fast external card reader, an Extreme IV card may let you download your pictures much faster to a PC.

 

[kifenzo]

thats what i wanted to know! thanx man... but is it for sure that I won't get better camera (not considering pc/reader) performance with lets say IV sandisk comparing to extreme III which is 20mb/sec... i wonder...