Memory Card Current Drain

[Calicajun]

Have been told by two different camera stores that CF cards draw more current than SD cards. Not sure if I buy that and even if it is true would one card really draw enough current to make a difference on battery life while using the camera?

Just curious as I can't see that making a difference on what camera someone (me) would buy.

Craig

[JimC]

I've read that, too. But, I don't know the exact differences between them.

From my perspective, it's a very minor issue.

Modern cameras are becoming more and more efficient from a battery drain perspective. It's not uncommon to see some modern DSLR models get close to 1000 images on a single battery charge (using a CompactFlash card, and needing to worry about moving optical elements in the lens around for Autofocus purposes).

My latest camera (a Sony DSLR-A700) has a CIPA rating of 650 shots/charge. But, that rating assumes that you're using flash for some percentage of the images, and from what I'm seeing, it's on the conservative side (I think it will do a lot more than that on one charge, even if you spend a lot of time reviewing images you've shot).

So, the difference in current draw between Secure Digital and CompactFlash is not something I'd worry about.

[TCav]

Lexar specifies that, intheir SD Cards, read operations require <33mA and write operations require <35mA. In their CF Cards, however, read and write operations require 50mA in 3.3V systems and 65mA in 5V systems.

See:
http://www.lexar.com/digfilm/sd_specs.html
http://www.lexar.com/digfilm/cf_specs.html

Higher performance cards will draw more current, but it seems that what you heard is true.

But read and write operations to a flash memory card constitute only a very small portion of what a digital camera uses it's battery for. I suspect that a digital camera uses far more battery power to backlight the LCD display than to read and write data to the flash memory card.

[Calicajun]

Thanks Jim,

It really wasn't something I was worried about, just curious. Seems there is so much more to know about the current line of cameras on the market today, as to the cameras I started with a while back.

Thanks,

Craig