All your eggs in one basket...

It is often said when people are seeking advice of flash card purchases that they should opt for a greater number of smaller cards over fewer larger cards, the reason being cited that if you say get a corruption on a 8GBcard, you loose more than if you had a corruption on a 1GB card, i.e. all your egges in one basket.

Is this actually true? I have been thinking (uh oh) but I have no conclusions yet...

This is all theroetical I am attenping to get an interesting discussion going here

1. First lets say a card has the same chance of failure regardless of capcity for this excercise lets say 1 in 1000 hours of use. I cycle my cards so they all get used.
1. a: I own 8 1GB cards therefore there is a 8 in 1000 hour chance of a failure, however it will only affect 1/8th of my images. As statistics go after 10000 hours I would have had 80 failures and lost 80GB of images.
1. b: I own 2 4GB cards therefore there is a 2 in 1000 hour chance of failure, hoever it will affect half my photos. As statistics go after 10000 hours I would have had 20 failures and lost 80GB of images.

1.a and 1.b over time show no real difference.

2. Second lets say a cards chance of failure is based on capacity and will there is a 1 in 1000 hour chance per GB. Again I cycle my cards so they all get used.
2. a: I own 8 1GB cards therefore there is a 8 in 1000 hour chance of a failure, however it will only affect 1/8th of my images. As statistics go after 10000 hours I would have had 80 failures and lost 80GB of images.
2. b: I own 2 4GB cards therefore there is a 8 in 1000 hour chance of failure, hoever it will affect half my photos. As statistics go after 10000 hours I would have had 80 failures and lost 320GB of images.

2.a and 1.b over time show a greater risk in larger cards, i think this is possibly the more true scenario as the greater the capacity the more components the higher chance of failure.

What do you think? I know the failure rates are way too high for real life, these are just easy numbers, they also don't take into acocunt failures that don't cause the complete loss of a card

My opinion is that if we buy only the best cards we shut not have much problems.
I have 4 Sandisk CF cards and untill now I have had no problems at all for two years.

Good luck for all of us CF cards users.

has anyone actually ever had a CF card fail on them?

sirsloop wrote in post #2145307
has anyone actually ever had a CF card fail on them?

Yep! though I did manage to retrieve about 70% of the images from it with a rescue program. Card showed as empty rather than full but would not allow images to be written to it. I ended up doing a paid job free gratis and reckon on having got off lightly!

For me the biggest problem is that if a whole shoot is on one card (8 gig say) then you loose the whole shoot. If however you shoot 4 2 giggers you would loose 25%, which would still be a problem if that 2 gig card contained all the church shots at a wedding say but slightly less of a problem than loosing the whole day.

I tend to swap cards well before they are full and make sure I have some images of each part of a shoot on seperate cards especially at a something like a wedding which would be hard to re-shoot. Swapping cards takes a few seconds so why take any risks that are easily avoided.

Remember that SODS law say that if something can go wrong it will do so at the most awkward moment.

I don't think it's so much the total gigabytes you lose as the fact that you lose ALL the shots from one shoot - if you spread 'em out the shoot may still be salvageable. If you shoot weddings how are you going to explain to the bride+groom that they didn't get a single shot from this once-only event? Explaining that you missed 1/8 of the wedding (say, some of the reception) is a much easier task....

That's why I wouldn't buy a high capacity card like 8GB.
I rather have 4x2GBs or 2x4GBs cards instead.

I guess I would say if I have four 1GB cards I am 4 times more likely to lose the card than if I have one 4 GB card. I think that chances of losing the card are much greater than the possibility of the card becoming corrupt.

Is this all assuming that you guys shoot in RAW? I know rarely do I shoot more than 450 pics in a shoot (using 2gb cards) so I wouldn't be switching cards, therefore, if the card failed I'd loose the whole shoot regardless, so it's a bit of a moot point for me.

FlyingPete wrote in post #2143235
It is often said when people are seeking advice of flash card purchases that they should opt for a greater number of smaller cards over fewer larger cards, the reason being cited that if you say get a corruption on a 8GBcard, you loose more than if you had a corruption on a 1GB card, i.e. all your egges in one basket.

Is this actually true? I have been thinking (uh oh) but I have no conclusions yet...

This is all theroetical I am attenping to get an interesting discussion going here

1. First lets say a card has the same chance of failure regardless of capcity for this excercise lets say 1 in 1000 hours of use. I cycle my cards so they all get used.
1. a: I own 8 1GB cards therefore there is a 8 in 1000 hour chance of a failure, however it will only affect 1/8th of my images. As statistics go after 10000 hours I would have had 80 failures and lost 80GB of images.
1. b: I own 2 4GB cards therefore there is a 2 in 1000 hour chance of failure, hoever it will affect half my photos. As statistics go after 10000 hours I would have had 20 failures and lost 80GB of images.

1.a and 1.b over time show no real difference.

2. Second lets say a cards chance of failure is based on capacity and will there is a 1 in 1000 hour chance per GB. Again I cycle my cards so they all get used.
2. a: I own 8 1GB cards therefore there is a 8 in 1000 hour chance of a failure, however it will only affect 1/8th of my images. As statistics go after 10000 hours I would have had 80 failures and lost 80GB of images.
2. b: I own 2 4GB cards therefore there is a 8 in 1000 hour chance of failure, hoever it will affect half my photos. As statistics go after 10000 hours I would have had 80 failures and lost 320GB of images.

2.a and 1.b over time show a greater risk in larger cards, i think this is possibly the more true scenario as the greater the capacity the more components the higher chance of failure.

What do you think? I know the failure rates are way too high for real life, these are just easy numbers, they also don't take into acocunt failures that don't cause the complete loss of a card

Its an interesting analysis, but compact flash is quite rugged and very reliable. They do ware out aparantly but it takes so many cycles it is said to not be an issue.

I suspect that many supposed CF problems are due to people using the camera with the battery on in a low state. There seems to be a risk if the the display is showing 1/4 full, I always change batteies when I get to that point since I had a camera lockup event.

One must also consider the probability that you will be out in the field, take your camera out of the case, and suddenly realize that your memory card is back at home in the card reader.

Someone who's been thinking and finds himself/herself in this situation will just pull another card out of the camera case (and still have a couple more spares waiting).

As I said in another thread, I think the main risk is making a mistake yourself and losing the card, or mishandling it otherwise so that you lose pics. With several cards, you spread that risk.

For my 20D, 2 GB cards seem to be about ideal. 1 GB is too small, and 4 GB is only needed in special circumstances like marriage.

P.

A few pro's I know replace their cards every year. Out with the old, in with the new.

I'm planning on trying to stretch mine out for two years and then replace them. Just another cost of doing business.

you can't go wrong listening to old idioms.

Some good points here, I only took into account a 100% failure which is indeed a rare event.

Leaving a card at home etc are all good points for having multiple cards, I actually had my 2GB stolen recently luckily it had no images on it, or it would have been 180 odd CR2s gone

Having the card actually fail, is not really what I am worried about. Losing the card or having it stolen seems more likely to me. However, when I shoot RAW I like to use 4GB cards, and have really standardized on that size. It is very convient to use 4 GB then when they are full, burn it to a DVD. 512 MB cards match up well with CDs.