memory cards information for cameras.
Wow what a subject to post about , more fool me, but here we go.
I Have Sandisk which is what below refers to, other makes may show different information on the cards
there are 4 different types of memory cards CF ( Compact flash) SD (secure digital) and micro SD cards.
Also recently introduces XQD cards which I understand are for better performance but never seen or used one so can't comment on it
The following applies to first three so I won't repeat on each individual one
The first big mistake I think is made is looking at the card capacity known as GB ( gigabytes). Why? simply because it does not give any indication of the transfer rate of a picture to the card.
What should be the first thing to look for is the MB/s which is the transfer speed which should be also printed on the card information. This will help stopping buffering. Higher transfer speed means more expensive card even though the GB is the same
So what is buffering? that is when the card can't keep up with the camera transferring photos, so eventually the camera stall until the card catches up. I learn't this from past experience at a critical time of continuous shooting a long time ago
So what speed should one look for? I would say nothing less than 60 MB/s and preferably 90 MB/d upwards to prevent buffering
Next we go back now to memory capacity which is obvious.
But hang on a minute cards can crash, so ask yourself is it better to have say a 32GB card than a 64GB card costing more or get 2x32GB cards.
card quality is also printed in what it is designed for eg SDHC-Extreme etc which also is reflected in the card price.
I have just ordered another 32gb card for that very reason.
Now there is also another consideration is card class.
This is really more to do with video recording the recommended is class 4 but up to class 10 for high quality video work . I usually get on about class 7 which suits what I do anyway.
Another thing often overlooked is on the side is a sliding lock which prevents accidental photo removal, worth using if your camera can't lock photos for you.
On genuine Sd cards there should be (at least with Sandisk) a serial number and on CF cards printed on the side. Most fake cards don't have this ident. marking so one to watch out for. Don't know about other makes as i have never owned one.
One other point worth a mention is the size of the photo being transferred from the camera. The larger the photo data the more that has to be transferred and this will affect the amount before the buffer is hit, RAW files being much larger than Jpeg files
In ending there is a lot more information on a card than at first glance, and understanding what it all means will help in choosing the right memory card you need