Insights For Success

Strategy, Innovation, Leadership and Security

SD Card

What's the best SD card?

GeneralEdward Kiledjian

SD Cards are everywhere. Whether you are using them in your video gear or camera, choosing the right one can make all the difference in the world.I needed to find the best SD Card I could buy and am sharing it with you. 

In tech, there is always something better if you are willing to pay more. So what I was looking for was the best value proposition. 

What to look for in a SDCard ?

When evaluating any external memory, you will typically use the same evaluation criteria :

  • Speed
  • Reliability
  • Warranty
  • Price

Many android phones will test the SDCard  speed while preparing it for use and will warn you if it is believed to be too slow. A slow SDCard can make the entire phone slow and sluggish. Also you should be saving your photos and videos directly to the memory card so a slow card mean slow click to click speeds.

The smartphone has become the primary camera for many users and since you are storing your important memories (photos and videos), reliability is important. Nothing frustrates more than losing your memories because of a technical issue. SDCards have become incredibly reliable but choosing a strong brand is important to protecting these memories.

Electronics die. Sometimes an SDCard will live for 10 years other times it will die within 90 days of first use. You just can't tell so it is important to chose a product that is backed by the manufacturer.

Price... Price...Price... When choosing the best SDCard, price was an important factor. You could always pay more to get better (faster, bigger, etc) but most people want a card that is good enough.

The tests

I tested 12 of the best known brands (Including Toshiba, Transcend, Samsung, PNY, Lexar, and some lesser known Amazon brands). 

The SanDisk Extreme Pro came up on top every time. It tested as the fastest,  when reading and writing from a desktop, which means your camera will spend less time writing and your post photo workflow will be much faster. 

Most modern cameras will take pictures faster than SD Cards can record them (typical dSLRs save pictures at 200MB/s and some point and shoots in the low 100MB/s.) Obviously the faster the card the faster your camera will be able to offload pictures from its internal memory to the card thus preventing the dreaded slow shutter to shutter issue.

As for videos, most device record at between 30-100 MB/s, so you should be ok with this card even at 4K resolution. 

What I especially liked about it is its weather proofing. I snapped pictures then dunked the card in water (outside of the camera of course) for 1 minute. Lat the card dry up and it worked like a charm. I often use my Olympus Though waterproof camera so if the unthinkable occurred, I would likely be able to save my images (at least).

SanDisk also bundles its cards with a limited Lifetime warranty. 

My second pic would be the Samsung PRo Plus (if the SanDisk is not available).

How many SD Cards should I buy?

The other question I get asked is regarding what size of card to buy. I typically recommend that you carry multiple cards and rotate between them. Nothing would ruin your day more than losing all your pictures because of a malfunction. Buy the largest size you can afford as long as you can buy at least one-2 extra cards of the same capacity.

Most of my cards are 32-64GB in size and on a multi day trip, I will typically have 1 card per day. If the unthinkable happens, I only lose 1 day of memories. 

Is your SD card hacking you?

technologyEdward Kiledjian
CC Image - Flick user scanlime

CC Image - Flick user scanlime

Think of all of the information your SD cards have seen, questionable pictures, sensitive data. Hardware hacker Bunnie Huang (link) gave an interesting presentation to the Chaos Computer Club Congress that highlighted the fact that SD cards are micro controllers with lax security that can easily be used to trick or hack you.

He first sets the tone of the presentation with this statement:

"lash memory is really cheap. So cheap, in fact, that it’s too good to be true. In reality, all flash memory is riddled with defects — without exception. The illusion of a contiguous, reliable storage media is crafted through sophisticated error correction and bad block management functions. This is the result of a constant arms race between the engineers and mother nature; with every fabrication process shrink, memory becomes cheaper but more unreliable. Likewise, with every generation, the engineers come up with more sophisticated and complicated algorithms to compensate for mother nature’s propensity for entropy and randomness at the atomic scale."

He then explains that engineers add smarts to counteract this act of god (which is where the power for evil comes in):

"These algorithms are too complicated and too device-specific to be run at the application or OS level, and so it turns out that every flash memory disk ships with a reasonably powerful micro-controller to run a custom set of disk abstraction algorithms. Even the diminutive microSD card contains not one, but at least two chips — a controller, and at least one flash chip (high density cards will stack multiple flash die)."

So these microprocessors contain special logic (algorithms) that detect defects and then only make available bits that are expected to be good. Also cards contain more space than shown as available (to ensure the promised amount stays available). This means that a "bad actor" can change the firmware on an SD card to copy data to this hidden storage space. This also means a card can show 16/32/64gB as available when it only contains 2GB (think of low cost no name SD cards from questionable Asian sources).

With this presentation, expect someone to develop an SD card hack to turn these little cheap trinkets into Arduino competitors. 

Not sure how we will secure our SD cards from compromise but I guess you should be buying your cards from reputable resellers and only buy top name brands.