CF card capacity

[Graham00]

i have one of two Sandisk extreme II 2gb CF cards, my top plate display shows 187 shots on an empty card, so i shoot 85 shots some on CH (continuous high) and it then says 155 left, how is this ? i have it set to jpeg Large, highest quality.

 

[Graham00]

Shouldn't it say 102 left not 155 ?
It doesn't bother me that i have that more shots remaining than i should have i'm just worried i may have a faulty card, if this is common i'd like to know, thanks.

 

[andrewc]

JPG is a compressed format so depending on the image complexity it will compress to different levels.

 

[neil_g]

not necessarily.. image size depends on factors like image noise and detail.

 

[Graham00]

Thanks guys, that's good to know when shooting aircraft etc, i have a sort of reserve available before switching cards.

 

[aligibbs]

It will decrease hugely if you shoot at high ISO's.

 

[-Rob-]

The number of shots an empty cards says it will fit on it is just an estimate and generally on the conservative side. It will probably assume you are going to shoot all your images with a lot of comlex detail in them which takes up more data than a simple shot with a lot of a single colour in it.

My 8Gb cards say I can fit 355 images on there but I usually get close to 500 before the card gets full.

 

[Graham00]

This is great and i didn't know this, if a roll of film say's 24 exposures on the tin, you get exactly 24 exposures.

 

[18-270]

Looks like this ones been coverd :crowded: