April 9, 2013

A useful SD/SDHC to CF Extreme High Speed Adapter

SD/SDHC to CF Extreme High Speed Adapter packed
With memory chip transfer rate speeds continuously increasing and prices continuously dropping one can have an 16 Gb 400X Compact Flash card at  the cost of a 2 Gb 133X CF a few years ago.
So there is not so much to be invested in memory cards as it used to be.

But yet the increased popularity of SDHC memory cards that were once sold at almost equal prices per Gb made them available at almost half the price of CF memory cards today.

SDHC memory cards, due to bus restrictions, do not equal the transfer rates met with CF cards, however they can cope very well with the demands in transfer rate speed of many older cameras. Par example a contemporary Class 10 SDHC card is by far faster than an older 80X, 133X or even 300X CF card as it will be manifested further below.
Another interesting fact is, that there are available Wi-Fi cards in SD format while not in CF format.
Where I'm getting to? Since such a comparison may become of meaning only if a CF card can be substituted by an SDHC card? Well, here the answer comes from an SD/SDHC to CF type II adapter made in Taiwan.

The Adapter
By declaration the specific device is the 3rd generation of SD to CF type II adapters supporting UDMA and promising better compatibility with SDHC cards and SDHC WiFi cards.

  • Supports all capacities of SDXC / SDHC / SD cards
  • SD 3.0 compatible accepting Class 10 or UHS-1 cards
  • Accepts most WiFi SD on the market
  • High Speed CF interface with Extreme performance
  • Supports CF true IDE mode / memory mode / IO mode
  • Equipped with push-push SD socket
  • Supports Windows / Mac / Linux
SD/SDHC to CF Extreme High Speed Adapter pack front
The SD to CF type II adapter comes in a small clear soft-PVC case sealed between two illustrated cartons. The front side shows the type of card in bold print and the compatible devices in smaller print. 
SD/SDHC to CF Extreme High Speed Adapter pack back
The back side is quite explicit enumerating the adapter features as well as a few short operation instructions of how to insert / extract an SD card and useful hints / precautions for use with a WiFi SD card.
SD/SDHC to CF Adapter w/ pvc case
Taking the front and rear cartons apart the sandwiched clear plastic case may be opened. If you care to trim the plastic flaps around the case you may keep it as a handy storage case.
SD/SDHC to CF Adapter top view
The adapter top surface is covered with a glossy label, which besides the logos has a small triangle that indicates the CF card insertion direction (pins side) and a small SD card drawing with an arrow which in turn indicates the SD card insertion direction.
SD/SDHC insertion into CF Adapter stages illustration
The adapter is equipped with a spring loaded push-push SD socket on one side. It operates like most camera SD sockets. You just push the SD card all the way into the socket and it locks in place. To extract you just push again and it comes out. With the SD socket opening on the side, the adapter has to be removed from the camera in order to exchange SD cards. It may sound inconvenient to some, who would expect to be able to insert or extract SD cards without removing the adapter from the camera but it is impossible. In order to maintain the CF type II dimensions the SD card socket opening cannot be placed elsewhere.

Transfer rate comparison
A logical question, when dealing with a memory card adapter, is how much its interference affects the efficiency of the memory card itself.
In this respect, I run a few data transfer tests with available equipment trying to establish a proof about the SD to CF extreme adapter efficiency. My tests are not meant to define the maximum performance of the cards under test or to disapprove the manufacturer specifications, but to present measurable data of any differences.
For the test, I chose to use 325 small size jpeg files totaling 795 Mb instead of a large file that would favor transfer rate parformance, in order to make the test a little more stressful, with open-write-close file operations, so be closer to every day use.
My first available test machine was an older SONY VAIO laptop which is equipped with MS Pro, SD and CF card slots with readers on board. These, combined with its ultra fast SSD I assumed that would be perfect for the purpose as there would be the minimum possible interference from the testing device as would be with an external USB card reader.
Further, I had available two 16Gb SDHC cards one SONY Class 4 and one Maxell Class 10 which I tested in the SD card slot first (Table #1) and via the SD to CF adapter in question in the CF card slot next (Table #2).

Transfer of 325 jpeg files / 795 Mb total in on board SD card reader.

Table #1Write TimeTrans. RateRead TimeTrans. Rate
Sony  SDHC 16Gb Class 42'.21".75.61 Mb/sec1'.42".27.78 Mb/sec
Maxell SDHC 16Gb Class 102'.14".45.91 Mb/sec1'.41".27.85 Mb/sec

Transfer of 325 jpeg files / 795 Mb total via SD > CF Extreme Adapter in on board CF card reader.

Table #2Write TimeTrans. RateRead TimeTrans. Rate
Sony  SDHC 16Gb Class 41'.34".58.41 Mb/sec44".917.71 Mb/sec
Maxell SDHC 16Gb Class 101'.11".511.12 Mb/sec49".016.22 Mb/sec

At first glance I was impressed reading the results as it seemed that the SD to CF adapter not only did not deteriorate the SD cards performance but on the contrary it enhanced it. I could have attributed the increase in performance to the direct ATA bus of the embedded CF reader which is wider but a second look into table #1 made me suspicious since Class 4 and 10 card results were very close, while in table #2 the Class 10 card was significantly faster in writing speed.
I guess the embedded SD card reader is too old to cope with contemporary SDHC cards and had reached its limits constricting the card performance.
Therefore, I proceeded in rerunning the tests on a desktop PC with a quad-core processor and faster RAM, but using a USB 2.0 SD reader and a USB 2.0 CF reader.

Transfer of 325 jpeg files / 795 Mb total via a USB 2.0 SD card reader.

Table #3Write TimeTrans. RateRead TimeTrans. Rate
Sony  SDHC 16Gb Class 41'.42".77.74 Mb/sec53".714.80 Mb/sec
Maxell SDHC 16Gb Class 101'.09".311.47 Mb/sec45".617.43 Mb/sec

Transfer of 325 jpeg files / 795 Mb total via SD > CF Extreme Adapter in USB 2.0 CF card reader.

Table #4Write TimeTrans. RateRead TimeTrans. Rate
Sony  SDHC 16Gb Class 41'.37".48.16 Mb/sec46".916.95 Mb/sec
Maxell SDHC 16Gb Class 101'.03".712.48 Mb/sec39".320.23 Mb/sec

Now, comparing table #3 with the previous table #1, the performance of the SDHC cards shows a dramatic improvement proving the issue with the laptop embedded SD card reader. However, further comparison between table #4 and table #3 shows once again a minor increase in performance by the utilization of the SD to CF card adapter. Such a minor increase can be attributed to the wider CF card bus more easily.

For comparison purposes, I run the same test on three Compact Flash cards of various speeds / transfer rates, I had available.

Transfer of 325 jpeg files / 795 Mb total via a USB 2.0 CF card reader.

Table #5Write TimeTrans. RateRead TimeTrans. Rate
Transcend 2Gb CF 133X3'.12".54.13 Mb/sec28".228.19 Mb/sec
Transcend 2Gb CF 300X1'.16".010.46 Mb/sec27".628.80 Mb/sec
Transcend 16Gb CF 400X UDMA43".718.19 Mb/sec25".930.69 Mb/sec

Since the hardware used was not the latest state of the art in order to ensure the optimal read/write performance of the cards the result values are only indicative and should only be considered in relation to the previous tables. There, by comparing tables #4 and #5 we can see that an SDHC class 10 card outperforms in writing speed the CF 300X card. In my opinion writing speed is actually more significant in emptying the camera buffer when recording than the reading speed that many card manufacturers promote for faster upload of photos to the computer.

The 3rd Generation SD/SDHC to CF type II adapter was tested with the Canon EOS 400D / Digital Rebel XTi, Canon EOS 50D and Canon EOS 7D cameras. Operation with EOS 400D and EOS 50D was flawless with no signs of slowing down the camera write operation to memory especially when using SDHC C10 cards. However, it seemed to me that EOS 7D operation slowed down a bit and faced also a compatibility issue with Eye-Fi Pro/x2 8GB SDHC card which was not recognized by the camera (which will be fully documented in another post). The issues with EOS 7D led me to search more in various sources and fora on the net, where I successfully discovered a firmware update for the 3rd generation SD to CF adapter released in August 2012 addressing specifically these issues. After the application of the update on the adapter any issues with EOS 7D were resolved and I intend to publish my findings as soon as I prepare some tests.
If you want you may download the firmware update from the following link to the manufacturer Dropbox bin:
(The link and zipped files were thoroughly checked for viruses upon the time of my download).

Very practical and innovative idea.
Does not affect SD card efficiency.
Good quality.
Logical price.

None so far. As I have used the adapter for a short period of time, I shall update and report any findings in the future, after testing with a WiFi card as well.

Owners of older cameras with CF type II card slots that mind for lower cost extra memory; students and/or enthusiasts in a tight budget that seek a used camera to enter the DSLR world, or owners of a number of SD/SDHC cards that would like to upgrade to a more advanced DSLR with CF type II card slot, and mind the extra investment required in CF memory cards.
Plus the owners of DSLR's with a CF type II slot, who would like to experiment with wireless transfer of their captures to a laptop / iPhone / iPad or direct uploads to the internet.
All of the above groups, may find the SD/SDHC to CF type II Extreme High Speed Adapter very useful.
Personally, I had started out with CF cards and believe that each camera should be used with the type of memory card it was designed for in order to obtain the maximum burst rate and/or uninterrupted video capture. On the other hand, I belong to the last group and would like to experiment with tethered WiFi shooting. So there will be a full review and report on SDHC WiFi card(s) soon.

This review and test was run on a single product sample, using the specifically described methods. Although the findings are good and some overcame the expectations for the product, it can not be used as a rule, unless more samples of the same product are tested. Furthermore, similar comparison tests should be run with comparative capabilities products so as to reach a solid conclusion.

I hope you found the review useful, thank you for viewing.
All Photos & Photosynths: © 2012 S.C.Vlachos

Price and Availability:
A logical price for the 3rd Generation Extreme CF Adapter should be between US$ 15 and 18 depending on the source. Please take care as to look for he latest 3rd Generation adapter. There are differently colored adapters sold by resellers as 4th generation but according to the original adapter manufacturers that is a marketing trick.
The Extreme CF Adapter is available either from Amazon, or from eBay worldwide.


  1. Very helpful - excellent!

  2. Thank you for your efforts.well done.

  3. From where can I buy this adapter??

    1. There are instructions and links in the "Price and Availability" section at the end of the above article.