My Canon camera has a CompactFlash slot, and I need to go on a long trip. What kind of cards do you suggest, and what speeds? I see cards with all kinds of x speeds, and some cheap unmarked cards too, and I don't know what to buy.
I would suggest buying the biggest cards you can afford.
Some people I've met, both online and offline, have a sort of wonky backwards logic to me, where they think having lots of small cards is somehow "safer" than a few large cards. This is prevalent with hard drives too. Five years ago, somebody would say "500GB is too big, I don't trust all my data on one drive, I'd rather have two 250GB drives". The same people now say "2TB is too big, I don't trust all my data on one drive, I'd rather have two 1TB drives". It's quite honestly ridiculous.
I'd suggest that a single card left in the camera is far better than always swapping out smaller cards. If anything, the out-of-camera time, and in insertion/removal time, is when a card is going to get most damaged.
The only real concern you need to have, aside from $$$ available, is the data transfer speeds. Within reason, the speed from the camera internals to the card is going to be so low that all those fancy marketed "x" speeds won't matter at all. What does matter, however, is the speed of the data as it moves from the card to the computer.**
** I'd like to take a minute here and say BUY A CARD READER! Your camera is supposed to be a camera, don't also use it to read your cards. A decent card reader runs maybe $20 or less, and can not only be found in office stores and electronics stores, but grocery stores and drug stores! **
The minimum speeds I would suggest are as follows:
4GB card = 45x or more***
8GB card = 133x or more
16GB card = 266x or more
This is so you may transfer a whole card full of images in as little as 5-10 minutes at most.
If the card has no "x" speed listed, assume the card is so incredibly slow as to be embarassing. I bought one of the earliest 16GB cards from a budget maker about two years ago. The card is so awful that the Nikon D3 and D200 buffers could fill up quicker than the card could store data. My 9fps and 5fps shooting was more like 2fps with this POS card (A-Data 16GB).
*** Sometimes the "or more" will cost a ridiculous amount of funds. It's not really necessary. It's one of those products that seems to be made only because people are stupid enough to buy it. I see a lot of filters going that route now too, touted as "HD" or "Digital" to profit off suckers. ***
When it comes to brand, stick to well-known memory manufacturers: SanDisk, Lexar, Kingston. SanDisk and Lexar often command a premium for the brand name, where Kingston is known for better prices. Avoid budget-grade and no-name brands like A-Data and Ridata, you'll be sorry if you buy those items (as mentioned in my above experience).
You'll often find the best deals on CompactFlash cards at: