Many thanks. There has been lots of interesting comment re my original 
question and I'll try and sum up some time soon. Here's a very quick 
comment to date.

What I wanted was a plug in that fitted a CF slot and wrote to an as 
small as possible external cage that took 2 x CF cards in parallel OR 
to an equivalent "redundant at source" store to overcome media failure 
once a frame was stored. CF is now very cheap and card cost is not the 
limiting factor. I'd run a 4 GB card IF I knew it was essentially 
bulletproof. As it is, I use N x 512 MB and interleave them manually.

Camera now is not what I had when failures occurred. So far I've taken 
20,000 odd shots since January 6th this year with no failures.

Old camera was a Minolta 7Hi "prosumer" 5 MP. Very nice camera. Now 
dead after 200,000+ photos. Brands that failed were mixed and quality 
in most cases. Included a Kingston 256 MB (London, very hot weather - 
totally unreadable by any means I've tried). Another 512 MB in Taiwan 
in hot but not so hot as London was evening weather. And a second 512 
MB failed within minutes adding weight to the camera related 
suspicions. Camera gets very hot under extended shooting which cannot 
help. Of these one was able to be reformatted and another appeared 
dead-dead. On trying it in several cameras, USB download, USB-card 
reader, CF adaptor ... it was dead. BUT on trying it in my new 7D DSLR 
recentlyish it would display in the camera sometimes (nice to see 
photos I thought were lost) but won't download (:-( ). - When viewed 
as a drive via USB the file names are scrambled and there are many 
rubbish directories and no tool I have will touch it BUT camera can 
read it in camera. ie card is probably logically scrambled but OK. I 
have had very occasional other failure which was soft formattable 
recoverable. I think I've had one other 512 MB failure with all frames 
lost but reformat recoverable.

My new camera has USB on-the-fly download to PC capability. (Minolta 
maxxum 7D DSLR, 7 MP).

Note that the very top cameras have two card slots (usually different 
media types) that can be run either sequentially OR written 
redundantly in parallel. The latter facility suggests that the pros 
also expect some failures (or that the design engineers hold CF 
company shares :-) ).

I will ask further about CF loss in action. However, having been burnt 
enough so far I can't assume all will be well in crucial shoots in 
future. Download to PC on the fly may turn out to be the way to go for 
critical stuff, with auto background file copy to an external drive 
incrementally. Wedding or other photographer wearing a laptop PC in a 
backpack (plus extra battery capacity) would be a sight to see :-). As 
I sometimes wear a 3 or 4 lens quick access bag at my waist and a belt 
bag at the back with a ?5? AH 6V SLA therein and quick change cable 
the step to wearable laptop may also be feasible :-). Almost. My 2 x 
Librettos are not quite up to the task. A Linux box with dual drives 
would do but camera software is not compatible.

This is a 'hobby' btw - not my 'day job'.

Re comment on being bad compared to film. Not so for me. I have lost a 
far higher percentage of film shots over time. One whole roll lost in 
Japan by processing lab. Occasional open back with film in 
[Doh!](preventable) (destroys surprisingly few frames if fast). 
Occasional failure to wind on at all (preventable). Occasional bad lab 
work leads to negatives that deteriorate. Some of these are not 
preventable without taking all work in house which is OK if that's 
what you want to do but ... . Apart from the bad cards i have never so 
far lost a digital picture in around ???300,000??? photos. I still, so 
far, have every frame that i have not purposefully deleted. All online 
on this LAN too fwiw.


        Russell McMahon

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