guide to compactflash specs, compatibilty (reason: older p&s)
in [Digital Cameras]
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From: invalid on 4 Oct 2009 01:37 24 Sep 2009,ray <ray(a)zianet.com> in news:7i1iqgF2t9b43U74(a)mid.individual.net: [snip mine] > See wikipedia article on compact flash cards - excerpt: > ========================= > Capacities and compatibility [snip] > [edit] Filesystems > > There are varying levels of compatibility among FAT32-compatible > cameras. While any camera that claims FAT32-capabilty should read > and write to a FAT32-formatted card without problems, some cameras > are tripped up by cards larger than 2 GB that are completely > unformatted, while others may take longer to apply a FAT32 format. > > The way many digital cameras update the files system as they write > to the card creates a FAT32 bottleneck. Writing to a > FAT32-formatted card generally takes a little longer than writing > to a FAT16-formatted card with similar performance capabilities. > For instance, the Canon EOS 10D writes the same photo to a > FAT16-formatted 2 GiB CompactFlash card somewhat faster than to a > same speed 4 GiB FAT32-formatted CompactFlash card, although the > memory chips in both cards have the same write speed > specification.[10] > > The cards themselves can of course be formatted with any type of > file system such as JFS and can be divided into partitions as long > as the host device can read them. CompactFlash cards are often > used instead of hard drives in embedded systems, dumb terminals > and various small form-factor PCs that are built for low noise > output or power consumption. CompactFlash cards are often more > readily available and smaller than purpose-built solid-state > drives and can be used to obtain faster seek times than hard > drives. =============================================== > > Bottom line is - if the camera knows fat-32 it will handle larger > cards. If not there is a 2gb (or possibly 4gb - depending on > implementation) imposed by fat-16 file system. > > Please note, too, that cards can easily be reformatted to whatever > file system you choose. I've done this in the past - using Linux > file systems. seems fat32 is the readable by the common OSes (if that was consideration). curious digression: http://www.google.com/search?q=boot+%22from+card+reader%22+|+% 22from++flash+cards%22+cmos seems pcs that boot from flash reader are not common (or maybe not yet made. i'm only reading google results.) i used recovery software, which did welll (recuva). then slow formatted from xp. then formatted in camera. i'll take a gaggle of "who cares" photos soon. maybe the slow format marked off bad areas of the card, or maybe the card will still go corrupt quickly. thanks
From: invalid on 4 Oct 2009 01:40 24 Sep 2009,J�rgen Exner <jurgenex(a)hotmail.com> in news:8mhmb51qqdkv8psn4k22p256ba7mlgl0fs(a)4ax.com: >"invalid(a)com.invalid" <invalid(a)com.invalid> wrote: >>i have a 512 mb card that's gone bad. >>canon tech says the s200 (aka ixus v2, 2003) takes up to 2 gb >>card, > > What does the manual for your camera say? nothing (unless i missed that spec, which i doubt). Which implies that my camera is so old, that manufacturers didn't bother distinguishing fat16 from fat32, because no cams used fat32. > CF supports a max size of up to 137GB, although of course > individual devices may have a lower limit for various reasons. > >>but wouldn't say >>why. and other comments had me doubt his advice on compatible >>card. > > Maybe he is confusing CF and SD. The SD spec indeed limits the > size to 2GB, only SDHC allows for up to 32GB and the brand new > SDXC format finally for up to 2TB. i suspect the tech was assuming smaller cards are lower priced and knew fat16 limited my cam to 2gb. (I don't know why he didn't just say "fat16 goes to only 2gb," since we discussed formatting.) currently 1 gb cards are disappearing from regular retail and are about same price as 2gb. 4gb are still slightly higher priced (so 4gb are a better deal if choosing based on $/gb) [snip] > jue thanks...
From: walt camden on 4 Oct 2009 02:37 On Sun, 04 Oct 2009 00:40:13 -0500, "invalid(a)com.invalid" <invalid(a)com.invalid> wrote: >24 Sep 2009,J�rgen Exner <jurgenex(a)hotmail.com> in >news:8mhmb51qqdkv8psn4k22p256ba7mlgl0fs(a)4ax.com: > >>"invalid(a)com.invalid" <invalid(a)com.invalid> wrote: >>>i have a 512 mb card that's gone bad. >>>canon tech says the s200 (aka ixus v2, 2003) takes up to 2 gb >>>card, >> >> What does the manual for your camera say? > >nothing (unless i missed that spec, which i doubt). Which implies that my camera >is so old, that manufacturers didn't bother distinguishing fat16 from fat32, because >no cams used fat32. > >> CF supports a max size of up to 137GB, although of course >> individual devices may have a lower limit for various reasons. >> >>>but wouldn't say >>>why. and other comments had me doubt his advice on compatible >>>card. >> >> Maybe he is confusing CF and SD. The SD spec indeed limits the >> size to 2GB, only SDHC allows for up to 32GB and the brand new >> SDXC format finally for up to 2TB. > >i suspect the tech was assuming smaller cards are lower priced and knew fat16 >limited my cam to 2gb. (I don't know why he didn't just say "fat16 goes to only >2gb," since we discussed formatting.) >currently 1 gb cards are disappearing from regular retail and are about same price >as 2gb. 4gb are still slightly higher priced (so 4gb are a better deal if choosing >based on $/gb) > >[snip] > >> jue > >thanks... The SD specs may limit FAT16 to 2G memory space, but there are 4G SD cards (not SDHC) that are a hybrid. They were designed to circumvent the 2G limitations in earlier cameras. I've been using 2 of them purposely formatted in FAT16 for the full 4G space on each for about 2 years now. (They arrive with a FAT32 format.) The FAT16 format speeds up the write speed on these cards to about 25% faster. You can still buy these hybrid 4G SD cards, just be sure SDHC is not in the label/title. Go to Newegg for example and browse the SD flash-memory section, there's 3 speeds of 4G SD cards being sold there. Note though, that in the case of video recording applications, you'll still be limited to 2G size maximum for any one file. But it won't prevent you from saving two 2G sized video files on a 4G SD card formatted in FAT16.
From: J�rgen Exner on 4 Oct 2009 07:59
"invalid(a)com.invalid" <invalid(a)com.invalid> wrote: >seems fat32 is the readable by the common OSes (if that was consideration). > curious digression: Well, it was introduced with Windows95 OSR2 and was supported in Linux not long after that. Can't comment on Mac. But anyway, that was a LOOOONG time ago. jue |