Thursday, June 21, 2012

Why you should not put an SD card in your Canon 5D Mark III (if you shoot to both CF and SD and care about speed)


I am going to start this by saying that I really like my Canon 5D Mark III cameras and use them for shooting everything including Bar and Bat Mitzvahs, landscapes, portraits, sports and more. But just after receiving my two cameras I started to play with the memory slots and experimented with the best way to use both memory card slots. My first thought was...it would be great to shoot RAW images to both cards as a backup measure, and my second thought was...I could shoot RAW to the CompactFlash card and JPG to the SD card.

Well...after some testing I have determined that, if you care at all about high speed shooting or clearing you buffer quickly, YOU DO NOT want to put a card in the SD slot. Why? Because, for some reason unbeknownst to me, Canon decided to build the 5D Mark III with one very fast CF slot which supports the newer UDMA7 protocol and a standard SD card slot which does NOT support the high speed standard (called UHS - for Ultra High Speed). This is really strange because many other cameras have come out with UHS1 compatible slots over the last year. Without UHS support, the top speed that can be achieved by the SD card is 133x. This is true even if you purchase a 600x SD card and insert it in the camera. The best you will get is 133x



 So...the only reason to use a really fast SD card is for faster downloading after the shoot.

At this point, you might be thinking, "why would the SD card slow down all of the data transfer of the camera including the CF card?" It turns out that the camera will default to the slowest card inserted. So, if you have a 1000x CF card in slot one and any SD card in the second slot, the very best buffer clear that will achieve is 133x. When shooting sports or any type of images with burst mode (6 frames per second), this is crippling. I want to shoot a bunch of images, have the camera clear the buffer as quickly as possible, and then keeping shooting more. Why would I want to clear data at 20MB per second when I could be transferring at 90MB per second or better? For this reason, I almost never use the SD slot in the camera. I want to take full advantage of my Lexar 1000x Professional CompactFlash card.

If you are a photographer who shoots in a studio or does not shoot in burst mode, this may not be a big deal. But if you care about clearing your buffer, you need to be aware of this.

One more thing. Most of the time, this is a hardware limitation and can not be solved with a firmware upgrade. Even more of a disappointment!

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105 comments:

Daniel Dunn said...

Yeah, I had discovered this also. You were able to explain it, which I couldn't do, but I was still super frustrated. Bummer, come on Canon, what is up with that?! Thanks Jeff

Ira Block said...

Jeff, this is very important information. Thanks so much for getting it out there. Ira

Ira Block said...

Jeff thanks so much for putting this information out there, it's really important to know.

Unknown said...

What about If your not even using the SD card or if the SD card is set to record the video only?

Anonymous said...

Thanks Jeff. Do you know of any camera that properly uses UHS write speeds?

Unknown said...

Darn, and I have a 400x for my Mark III. Like Hassan is asking... will it work just fine with video (only)? If it is set to video only, I would have to guess that it will utilize the full speed of the Compact Flash?

Thanks for the information.

Unknown said...

I have a 1D MKIV and use the SD slot only for back up and then only for full size JPEG's. When the need calls for it, I use my Eye-Fi card to display images on my smartphone (which could as well be a iPad) for viewing.

Jeff Cable Photography Blog said...

To answer some of these questions...there are numerous DSLR cameras from Nikon and point-and-shoot cameras from other manufacturers which are UHS1 compliant. But, honestly, none of them really take advantage of the high speed cards like they should. The biggest advantage of the UHS1 SD cards right now is in the download speeds (increasing your workflow). As for the question about shooting video with the 5D Mark III, I would recommend the Lexar 600x or 1000x cards since they are VPG rated (video performance guaranteed). Finally, this same issue can be seen on the 1D Mark IV which also has a higher speed CF slot (although not UDMA7) and a slower SD slot. But, since this camera came out a couple of years ago, this was excusable. Not sure how Canon missed this on the 5D Mark III, which is newly released.

Cliff Hall said...

From the title and text the impression is that with a SD card installed, even if not being written to will throttle the CF card, is that correct?

Anonymous said...

When writing only to the CF card while using the SD card as an overflow card, the speed of writing the the CF card is not throttled down. This article is relevant to only those who want to write to both cards simultaneously.

Anonymous said...

Nice to see that someone is talking about this, but I would like to ask what about other Canon DSLR cameras that are using SD cards, how do they behave?! Are SD slots in other cameras also limited at 133x speed, or not?

Anonymous said...

So if one was to shoot small JPEGs to the SD card, and Raw files to the CF cards, the Raw files would still be recorded 133x or slower?!

alex tuma said...

Nice. But i have big problems with the Lexar 1000x (16GB). Only the Lexar pro USB 3.0 reader work with this card. Lexar pro USB 2.0 and Hoodmann USB 3.0 and a other USB 3.0 CF Card Reader dosen´t work with this cards. transfer with 1 to 2,5 MB/S to Computer or sytem stop(2 Laptop 2 Workstation Win7 32 and 64 bit the same) so perfect speed in camerer but transfer to computer...bad

Roberto Farren | wedding photographer Boston said...

Jeff, I have found this to be an issue already with the 5d3 and had wondered why, my reasonably fast cards, were struggling with continuous shoots so much. So frustrating they have set it this way. I presume then that if you are using dual cards (with the SD for back up), that maybe writing a SRAW file to the SD card instead of full quality might increase the shot count achievable in continuous mode while still providing a back up, or would that still be restricted by the size of the file being written to the CF card? Guess I'll go test now. Thanks for the heads up!

Anonymous said...

For clarity - it sounds like you have the camera set to write to both cards - either as auto backup, or to write jpg to SD and RAW to CF.

"My first thought was...it would be great to shoot RAW images to both cards as a backup measure, and my second thought was...I could shoot RAW to the CompactFlash card and JPG to the SD card"

If this is the case - it makes complete sense for the CF card to slow to match the SD, that way the SD is always at the same point in the process and there would be fewer (from a programming standpoint) issues to deal with than if you were clearing the buffer to one media faster than the other...

I have mine set to auto switch from CF to SD when the CF is full and I've not seen what you've described.

I've done some tests and have seen immense increase in throughput with UDMA7 over UDMA6 - especially re: buffer clearing... on both my 5D3 as well as my 1D4 (tho the 1D4 needs a firmware update to leverage UDMA7).

- Will

Anonymous said...

This is great information. I wish I had known this before using the 5D3 at an Air Show this weekend. I was shooting RAW to the Cf and small JPG to the SD. Then switched to Large JPG in the CF and small JPG to the SD to "speed it up". Didn't help that much. I now know why. #CanonFailedHere

Unknown said...

Excellent article, Jeff. That's interesting that Canon decided to add the SD slot then give it such a slow SR card reader. Good stuff man!

Ricky

Jamie said...

Thanks for the info, Jeff. I shoot the Mk IV and up to now, have nearly quit shooting with CF cards because I can mount the SDHC right into my MacBook Pro.

Guess I'm going to have to buy a handful of new, fast CF cards...

Jamie

Steve S said...

Yeah I had originally thought that the SD card slot would give me a good way to ensure some redundancy in my photo storage. Though I didn't know why, I figured out pretty quickly that trying to dump duplicates to the SD card was slowing me down. I just assumed that it was a limitation of SD cards, not the specific slot implementation.

For the most part the only practical use I've found for it is leveraging an EyeFi card. Then I'm only righting out medium resolution jpegs. Does lead one to wonder why Canon even bothered to include the slot if they weren't going to make it fast enough to keep up with all the data they are pushing around on the new 5D.

Steve S said...

@Cliff no, it's only if you're writing data that it slows things down. Basically if the camera fills the buffer, it throttles the shooting speed. Since the SD card slot is much slower, it can't dump the buffer fast enough and ends up throttling the whole thing.

If I shoot without the SD card writing enabled it doesn't slow down. When I shoot with medium quality jpegs it doesn't slow down. I haven't shot with high quality jpegs but basically it's just a factor of bandwidth to the card.

Andre said...

Yes, very good info, Jeff! Thank you. I am trying to upgrade from my XSi (I have SanDisk Extreme SD card in this unit). It was great news that the 5DMK3 supports it but now I will have to get the more expensive CF cards :O

In the electronics/circuit board P.O.V., it does make sense that it reads the slowest card inserted/detected (like motherboards in a computer, if the ram slot is to support PC3-12800 but two ram sticks were to install (1x@PC3-1600 and 1x@PC3-12800), the board will read the slowest ram speed and tweak the faster ram to be at the slower speed.

However, Canon in going that route doesn't seem to make sense at all. I would like Canon to fix it via firmware but I doubt this could be done.

Unknown said...

Jeff - can you clarify the article/headline?

Having a SD card in the camera doesnt necessarily mean it'll slow down - only selecting to record to the SD card will do that.

So you can have both cards in, full speed when not recording separately/recording to multiple (ie Recording to the CF card, and using standard or autoswitch)

When you want to record to both, change the setting, or if it's just backing up the CF at the end, you can do that in the menu.

Worth having a backup SD card to hand, in the camera either to backup at the end, or as a safety net through autoswitch

JacoleRoux said...

love my 5dMIII too, but Canon had to figure some way to force people to buy the 1DX! "hey lets slow down the SD slot!"

Anthony G. said...

Sorry - this is *not* new information. In Canon's defense this is all explicitly stated on page 117 of the owner's manual. If you are concerned about burst mode then leave camera on Standard or Auto Switch Card. The manual states: "When Rec. separately is set, the maximum burst will decrease greatly. (See pg 121)". Pg 121 further explains on the matrix the burst rates and also states: "The Maximum burst rate applies to High Speed Continuous Shooting", it then extrapolates that it is referring to UDM7. It may seem obvious then since the SD cads (if engaged in the two other record modes modes) would have to be the lowest common denominator. On page 32 the manual also states the camera does not comply with UHS standards although these cards can be used.

Now a good work around to this if in the field and you need the backup feature but also the fastest burst mode on a UDMA7 CF card is set the camera to record only on the CF card (Standard Mode). Be sure the CF is the card chosen to record (under Record/Play menu) as well. Now you can copy your images to the SD card by pressing Menu. Choose Menu section 3, sub menu 1 and select "Image Copy". Here you can define your Source (the CF card) and the freespace on Card 2 (SD card) there you can copy all your CF images to an SD card without losing burst mode speed and still have your backup.

KDS said...

I would love to know exactly why Canon choose to limit this but I suspect they choose to limit the speed as being either easier or cheaper in development or in cost of hardware.

Regardless of the reason I believe its unacceptable in a $3,000+ (use) camera . Though many may dislike SD cards they are now generally just as dependable as cf cards, much cheaper and readily available especially for use as backup.

So do all other Canons have the same trouble? No.

I own a Rebel T2i & 60D.
Clearing the buffer & writing to card is blazing fast using sandisk extreme 95/sec cards on my 60D. I can shoot continuous 5.5 fps (±) JPEG and the buffer clears faster than Canon product info states is possible.

Just now shooting my 60D
23 raw+JPEG in 10 secs.
14 raw+JPEG in 5 secs.

Shots till buffer slows everything at
6 sec mark
22 Raw(only)

30 sec mark
162 Large jpeg (only) = 5.4 per sec
Stopped at 30 sec because buffer never gets anywhere close to filling.

All in manual focus & 100 iso

Canon still great but its darn irritating.

Chris Tennyson said...

I specifically bought a Lexar Extreme Pro 64gb SD when I got my MKIII after doing a bunch of research online so that I'd have faster speeds. Shot a concert this weekend, first time to utilize the frame rate and buffer. Kept scratching my head why it was topping out and stopping. Makes perfect sense now.

So pleased I wasted my money on this card and now need to buy a CF.

Thanks Canon. More annoying is that I sell your damn products for a living and your rep never bothered to mention any of this either.

Anonymous said...

Why cant Canon in a firmware upgrade offer an option to just write to the CF slot and then write to the SD card when idle.

I do not care that the images are written immediately after to the SD slot. Just sometime after.

Anonymous said...

New Canon T4i is UHS-1 compatible. 1Dx has dual UDMA7 CF slots. Seems Canon went out of their way to reduce 5DIII capability.

Anonymous said...

Jeff - I'd suggest you append/change your title, it is very misleading. I've just done another quick test with my 5D3 with the SD card in and without an SD card and my write time to my UDMA 7 CF Card is *not* any different.

I think your title should be "Why you should not write to an SD card in your Canon 5D Mark III (if you care about speed)"

If you are writing to just the SD or both the SD and CF *at the same time* your write speed will be limited by the speed of the SD card.

You *can* have an SD *in your camera* and write to the CF and let the camera roll over to the SD when the CF is full. Then the buffer will write at UDMA 7 speeds to the CF till you roll to the SD, then at SD speeds...

- Will

Rich said...

I've been doing some testing on my own, regarding how how many shots you can actually take in burst on the 5DmkIII... and the answer can vary widely based on how you have the camera set up and what cards you're using. For instance.. common knowledge would say that shooting RAW+RAW would be slower because the RAW format has more data, but it seems that shooting RAW+JPEG is slower... I think it has to do with the 5DmkIII only having 1 processor so the processing of the JPEGS takes a toll on burst.

Here are my results.

Shooting RAW/RAW with a Sandisk Extreme CF (60 MB/S) and Sandisk Extreme Pro SD (95 MB/S) I was able to get 18 shots before hitting the buffer

RAW/RAW with a Sandisk Extreme CF (60 MB/S) and Sandisk Ultra SD (30 MB/S) I was able to get 11 shots before hitting the buffer

Shooting RAW/JPEG L with a Sandisk Extreme CF (60 MB/S) and Sandisk Extreme Pro SD (95 MB/S) I was able to get 12 shots before hitting the buffer

RAW/JPEG L with a Sandisk Extreme CF (60 MB/S) and Sandisk Ultra SD (30 MB/S) I was able to get 9 shots before hitting the buffer

Shooting RAW/RAW with a Sandisk Ultra CF (30 MB/S) and Sandisk Extreme Pro SD (95 MB/S) I was able to get 18 shots before hitting the buffer

RAW/RAW with a Sandisk Ultra CF (30 MB/S) and Sandisk Ultra SD (30 MB/S) I was able to get 15 shots before hitting the buffer

Shooting RAW/JPEG L with a Sandisk Ultra CF (30 MB/S) and Sandisk Extreme Pro SD (95 MB/S) I was able to get 7 shots before hitting the buffer

RAW/JPEG L with a Sandisk Ultra CF (30 MB/S) and Sandisk Ultra SD (30 MB/S) I was able to get 9 shots before hitting the buffer

bryan said...

great article thanks for the info. i noticed it as well

Jeff Cable Photography Blog said...

As many of you have pointed out, the degradation in speed will occur when you are attempting to use both the CF and the SD to write files. If you have an SD card in the camera and are not writing to it, you will be fine. I am not sure why you would want that (except for overflow), but this is the case.

Someone also brought up the speed difference in writing RAW+JPEG vs RAW+RAW. This is also true on the 1Dx. I believe that this is due to the fact that the camera has to process the file twice (once for RAW and once for JPEG) which takes longer than clearing two RAW files from the buffer. I was hoping to shoot RAW+JPEG at the Olympics with the 1Dx but will now shoot RAW+RAW only.

Anonymous said...

Perhaps a correction to your blog is in order instead of putting a partial correction in the comment. The 5d3 doesn't "default" to the slower card speed. That is just the consequence of writing to both cards.

Kurt Paris said...

Writing RAW+JPG will still overall be faster if you are writing to both cards simply because of file size.

When shooting a wedding or other event where i am bursting i am shooting RAW + medium JPG (which if the poop hits the fan i sstil a workable file). Using a fast CF (Sandisk 90Mb/s) i typically hit around 24/25 shots before the buffer runs out.

I've personally found that shooting RAW+RAW (even if you set Smallest RAW for the CF) will be slower than shooting raw + jpg.

Unknown said...

I agree. The title needs to change. I had to read all the comments before I got the full page, and this shouldn't be. Thanks for bringing up any caution but also please do change the title. A friend is trying to decide between the III and the II, and this caught the eye right away.

Jeff Cable Photography Blog said...

I did update the title to clarify that this happens when shooting to both cards. Hopefully that will be clearer to everyone.

Adrian Staicu said...

Great article, but I was missing one thing, how is the speed with SD only?
Also they CAN fix this with software update, by writing data asynchronous to the SD card. You would do most of the high speed shooting to the CF card and clear the buffer, and then duplicate data to SD card when you are not shooting.

So don't just accept that SD slot is slow, complain to Canon about this and suggest "writing data asynchronous to SD card".

inicolau said...

As Jeff mentioned it is an issue when shooting to both cards separately. The Canon manual also states this. So technically you don't have to take the title of this article literally and leave the card out. Just set it to switch cards automatically and it will still use the CF at the higher write speed until it runs out of room and switches to the SD Card.

I rarely ever need the camera to switch to the SD card and when shooting engagements and weddings I'm not shooting at high burst rates so writing to both at a slower speed is not a biggie for many people. Also stated by Jeff.

Anonymous said...

Interesting reading about the decrease in speed when shooting RAW+JPEG vs RAW+RAW. Is there a trade off for RAW+mRAW/sRAW? Does that fall in the middle or is it quicker. I like the idea of having a RAW back up and can live with a mRAW. I don't know why the need to change the title of the post though, it's pretty obvious if you not writing to a card that it's not going to slow thing down isn't it?

Anonymous said...

Great and informative article along with all the comments. However I didn't notice anyone mention that the 5D3 was never meant to be the "race car" in the burst mode of the Canon line. Should high speed burst be your major concern,possibly the 5D3 should not be your first choice. For pro/semi-pro sport shooters, the 1D MK IV, or the 1DX or even the 7D may serve your need for speed better, I use my SD slot only as a transfer card from the CF card for select images.

Jeff Cable Photography Blog said...

A couple more things...

I know that whenever you write different types of files (RAW + SRAW) the camera will slow down more than if you wrote the exact same file type. This is due to the fact that the camera has to process the file twice. This is even true in my Canon 1Dx which has 2 UDMA7 CF slots.

As for using the 5D Mark III for shooting sports. Why not? At 6 frames a second and with the high ISO shooting, I see this as an excellent option. Not everyone can afford a 1Dx or would want to have that large of a camera to hold. It wasn't that long ago that we would have killed for 6 frames a second (and high ISO) to shoot sports!

Terrance Lam said...

I use both the combination of the 133x and the EyeFi card. I've never really found it a problem.

First I don't usuallly burst more than 3 at a time. Second, I never expected 6 fps to be a sport killer. That said, the way I use the second card is to turn it down to smaller JPG images and it doesn't affect the speed for me. Both in the 133 and the Eye-Fi, I shoot JPG images in the S2 format. I use this size because first I only use my RAW for my clients, second, S2 files with my Eye-Fi are much faster to transfer to my iPad for quick reviews.

I shoot occasionally for an event company and they only want S3 sized files, so it has't really been an issue that I can see. However I do agree that it's a bit of an odd decision on Canon, but in real world application, at least in my workflow, is not affected by this.

Anonymous said...

You shouldn't put it in there because it's not a Nikon LOL, jk. Very well-informed article, though.

dterryphotography said...

I was unable to duplicate the slow down of the CF card when using a slower SD card in my camera. It might just be a difference in the cards being used, but here are the results of my tests:

16Gb Sandisk Extreme 60mb/s CF card
4Gb Sandisk Extreme SD card (I don't know the rating)

Testing procedure, hold the shutter button down for 5 seconds then let go and wait for the camera to finish writing the images to the card.

With both cards in the camera:

CF = 12 seconds to write 25 images
SD = 22 seconds to write 18 images

I removed the SD card, powered off the camera, removed and reinserted the battery to make sure everything was reset, then repeated the first part of the test:

CF = 12 seconds to write 25 images

So the CF write speed (which is definitely faster than the SD write speed) does not appear to be hampered by having an SD card in the camera. At least ... not with this combination of cards.

Anonymous said...

David, the phenomenon occurs when writing one photo to both cards. If you shot 25 images on the CF and 18 images to the SD, you're not doing what this article is talking about. Moreover, it would take the same amount of time to write to both the CF and the SD because it happens during the same action.

Ken Wallace said...

Well--found this info just in time! Just deleted that 400x SD card from my Amazon cart.

PCB Design said...

I discover this post very useful and informative..Thanks for taking time to share your great experience and knowledge here with us..Keep it up..

Unknown said...

To add to the comments here...
I was shooting my first wedding on Saturday with my new 5D3. The whole point of 2 cards is to write to them at the same time. This was at request of many I believe including Jeff Ashcough ? a respected tog.
I had it lock up completely as in... camera off, display says it is writing the remaining 5 images.
I had to stop using the camera and revert to my second cameras. 5 or 10 minutes later the 5D3 display had not changed and with so many wedding images on the CF card I was really worried.
I had no option but to do something drastic to force it to respond. I elected to eject the SD card.
Once done the camera was happy again and I continued on CF only :(
This has to be all buffer related.... may be mine just has a problem, not sure..... !? :(
Not practically being about to use both cards at the same time is a joke! :( ...imho

Unknown said...

Thanx so much for this blog. I shoot a lot of different stuff, but discovered recently that writing separately is extremely #@*!!! for Bull Riding events. Next time I will take the evil SD out.

Kevin Hubbard said...

Thanks Jeff. Wish I'd known about this before taking my brand new 5D Mk III on vacation. I'd been using SD cards in my Rebel T2i, with the maximum speed that camera permits.

Bam!!!! Major buffering issues on several occasions!! Let me tell you, trying to photograph a dozen kids at a family gathering was a real challenge! Just saying that you don't have to be doing HD video or a more formal event like a wedding…a family get-together could get to be a problem if you're shooting quickly.

I'm off to the store to get a couple of fast CF cards and keep my SD cards for something else.

Thanks again!!

Unknown said...

I love the information you've provided. Now I've searched everywhere for an answer to the following question: Will the CF Card be slowed down to SD Card Speeds in video mode? (Assume that we're in [Rec. Separately] mode). This article talks at length about the limitations of photo mode.

Jeff Cable Photography Blog said...

Jamison, if you are recording to each card separately (not at the same time), you should be fine. This should be true for still images or video.

Unknown said...

Thanks for creating this great informational resource. Flex Circuits

Anonymous said...

Really too bad since CF cards, as a format, suck. I'll live with the limitation since SD is the only way to go.

XO Vision XD103 FM and MP3 Stereo Receiver with USB Port and SD Card Slot said...

I like your information which you provided about the SD slot card which is inserted in this camera from this facility we can take more and more videos with large space memory.

Anonymous said...

any news about this problem ?

Jeff Cable Photography Blog said...

There has been one firmware update for the 5D Mark III, but as I expected, nothing to change the SD speed issue. I still stand by my first thought, which is, this is a hardware issue.

Anonymous said...

Anyone know why my 5d mark 3 won't record video to the 2 diff cards at once?????? Did I miss this in the manual ! Both the same speed cards by the way.. Many thanks in advance

Dave

hd sdi cables said...

Thanks Jeff for this informative post. It was nice reading it

Unknown said...

copy pics over to sd card every now and then. delete from cf card and start again , the beauty of this is you dont need such a large cf card thus a 8gb card should be fine just so long as you keep dumping to the sd .the price of large capacity sd cards are much cheaper than high speed cf therefore costs should be quite low

Mads Barnkob said...

I have had great trouble copying the files from the CF/SD card through USB cable to my PC. It would constantly loose connection to the PC. Turns out it was caused by having both CF and SD card in at once, pulled the SD card out and no longer any problems.

ali naqvi said...

Its fabulous post....really great work..can i use this in
Plastic Cards
?

Anonymous said...

The reason why Canon put a slow SD card is very simple. It's for commercial purposes. In the mark 4 they might add 2 CF cards or something like that. Look closely and you will notice many more such features which could have been added to the mark 3, but they were not added. For example, a 36 MP sensor, built-in geo tagging etc. HDR technology already existed when mark 2 was in development (if the processor at that time was not capable to handle this fast enough, then they could have supplied software to do this on your PC. BTW, speed is not a big issue when you do HDR. I take at least a few minutes for 1 HDR pic). And they could have put the software for high ISO enhancement in the mark 2 (which would require only a software update). If Canon put all the goodness in 1 camera today, they would sell very few cameras tomorrow. So they must use these commercial tricks. I know it sucks, but capitalism also has its disadvantages.

Unknown said...

Dear Jeff,
I bought new canon 5D Mark 111 dslr camera.just wondering what is the best card to use it ?is it CF or SD? i saw heaps of comment in the internet says using SD not good as CF card?Also can you suggest me what is the suitable CF card and its capacity.i am not a professional photographer but i wanted to become .eg:64GB Sandisk extream pro 95mb or lexar 1000x .looking forward to hear from you.Thank you Jeff

Unknown said...

Hi Jeff,
could you also give me a suggestion what lense suits in my %Dmark 111 and what lens is best?
i bought 24-105mm and 70-300mm.just for curiosity and fun but i would like to become a freeland photographer one day i hope.your suggestions and comments apprieciated.

thank you Praveen

DSLr camera said...

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Unknown said...

Nice blog and the content seems very useful about cheap sd cards devices. The blog is really very helpful. Thanks for sharing such informative post.

Anonymous said...

Here are my test results from a 1D Mark II, it doesn't play nice with UHS cards...

2 shot burst, using single cards and then RAW to both cards.

Sandisk Extreme CF (30MB/s) - 2 secs
Sandisk Extreme SD (30MB/s) - 4 secs
Sandisk Extreme SD UHS-1 (45MB/s) - 6 secs!!!

Jay Dorsey said...

Great post. I was just getting ready to buy some class 10 SD cards when I thought I better check. Thanks for saving me the headache.

Anonymous said...

The post seems quite good and huge information is given to explore about cheap class 10 SD cards and the post is really helpful for me. Thanks for sharing your views.
Keep Further Posting....

Lane Pederson said...

My camera is a Ds Mark III. I am going to buy SanDisk Class 10 cards Read:95MB/s and Write:90 MB/s. If I only use this card do you know what the real speed will be? Thanks Jeff

Lane Pederson said...

Forgot to say the SanDisk cards would be SD on my previous post If only using the SD card in Large RAW can I get a fast speed i.e. 90MB/s?

Jeff Cable Photography Blog said...

Lane - first of all, I recommend Lexar cards! :) As for the speed, the best you will get is 20MB per second in the camera. The only advantage of a fast card is for fast downloading. I am hoping this changes in the 5D Mark IV (assuming there will be one with an SD slot).

SD card Duplication said...

Hi my friend! I want to say that this article is awesome, nice written and include almost all important infos. Id like to see more posts like this.

Anna said...

Thanks for posting this nice and descriptive post. Keep on posting these kinds of informative posts in future also. boston wedding photographer.

Anonymous said...

Thank you for the article!

Luigi said...

Dear Jeff
I suggest you to amend this article. I just bought a 5D Mark III a few weeks ago, and even with the SD card inserted, the CF card can use all of its speed.
In Set Up 1 menu select:
Record function: Auto switch card
Record/Play: 1 (which is the CF). With my 120MBs SanDisk I can get 22 frames before it slows down and in a bit less than 5 sec the buffer is fully cleared.
Kind regards
Luigi

Anonymous said...

Hi
I read the article before buying the 5D MKIII and assumed i could only use one of my cards for rapid fire bird shots. But, I decided to run some tests. I found my camera will run at same speeds (6fps) writing to either a compact flash 1000x or SD card (scan disk extreme 45M/S) with either one of them in alone, or with both of them in.
However, I get 32 images before buffering slows things down writing to CF and 13 frames with the SD, so CF is much better from that perspective.

I get no difference in rate of shots or number of shots before buffering issues when writing to the CF card with the SD card installed too.

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Gerry Hanan said...

Thanks Jeff - I usually shoot in the studio but twice a year I cover New York Fashion Week and that is the only time of the year I really need my 800x CF cards. Normally I borrow a 1DX or similar for FW but I just got a 5D Mark iii and was looking forward to the lower cost SD cards. I found your article in doing research about the different types of SD cards before pulling the trigger on 10 cards. Now I can avoid the bitter taste of dissapointment thanks to your post. Thanks for posting. Sure would be nice if Canon made this information front and center in the specs.

Jeff Cable Photography Blog said...

Hugo, please contact me at jcable@lexar.com and I will help you out.

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Anonymous said...

Great info! Thanks for this post Jeff.

Rob van Empel said...

Hello Jeff, Just to know for sure. I'm using the SD slot just for writing when te CF is full. If i set up the camera that way i do not notice any speed difference with or without te SD card. Is this your expirience also? Sorry if my English is bad, i'm Dutch so there can be errors.
Greets Rob

Jeff Cable Photography Blog said...

Rob - the slow down only occurs when you are writing to the SD card. So...if you are writing to both CF and SD together or just to the SD card. If you only write to the CF card, it will be very fast.

Unknown said...

Hi there,

Just by coincidence I found your article about the slow SD card phenomenon.
Since I started reading your 2012 post, I quickly scrolled to the botton of the comments section, hoping to find that the problem was solved by CANON (by means of smart firmware), but when I arrived at postings from 2015, the problems still doesn't seems to be solverd.. Bummer.
Most probably because it is a hardware design choice that gives us this problem.
I was already not a fan of SD cards for camera's, and I'm glad that I have a HUGE capacity CF card in my 5 Mk III, and never bought an SD card.....

Cheers

Robbert, Soesterberg, NL
www.herksen.com

2 littlefaces said...

Hello, Not sure if anyone has asked this already but what if I use a CF adapter for my SD card? would that make a difference?
Thanks

CarlosVanVegas said...

Now there are newer SDXC cards for example U3 Class 10, would these faster cards reduce/remove the laggt performance?

CarlosVanVegas said...

I see some other blogs say the 5D doesnt canot benefit from the speed of UHS-I SDXC cards but you could use them but end up paying dfor a card that wont truly benefit what youre looking for.

So to save on the cost probably best to stick with non UHS cards, but those will never best CF as already stated oh well, sorry to have wasted your time, I asked but then found the solution :)

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Anonymous said...

Hello,
I do agree with you and also put an SD card inside my digital camera to save all taken photos and videos. The SD memory card will often be really convenient for me to transfer and back up my camera data to another storage device, like my computer external hard drive. It is really good for me. But, one bad thing is that such SD card also is able to get some problems, like virus infection or not formatted error. Though I did have learned to remove such error by following the guidance of this article: http://www.icare-recovery.com/howto/sd-card.html, I still don’t want to face them again after experiencing several times
Hope your guys also will take necessary precautions to avoid such troubles.

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Rowery said...

It's little shame for Canon, that they didn't make camera that holds full speed with saving to both cards. But perhaps it's reserved for 1D :)

ufa said...

you make me understand it alot more.l'll try it out.

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