Benefits of a faster memory card when remote camera fills the buffer?

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I had a quick search and didn;t come up with too much on this.

I recently bought a couple of pocket wizard plus 3s. These can shoot at the full burst speed of the camera and on my first use i found that the buffer of my remote (Canon 7D mk2) was filled before my subject had reached the focus point.

Now I have 3 options here. trigger later (which if using 2x remotes may not be an option), set a slower burst mode, or buy a faster memory card.

So Does anyone have experience of how much of a benefit buying a faster card would have? I currently have one of these, that records at 90mbs.


I can see some lexar cards that record at 120mb a second, but lets say my files are 25mb thats only 1 more image a second i am going to get, and if the max burst speed is 8 FPS that isn't going to be much of a cost/benefit really, indicativly...

Anyone got any thoughts?
 
What is the fastest speed the camera will work at? If the camera is the bottleneck, there's no point putting a faster card in. Have you got a faster card that you can test with?
 
The limiting factor is probably the buffer on your camera. When that's full you are reliant on the buffer to card transfer time, which you can see is quiet slow.

Your best option is to shoot smaller files, it will then take more shots to fill the buffer and allow more shots to be transferred to the card per second.

Andrew HATFIELD | Architectural and Interior Photographer
 
does the buffer fill if you shoot jpeg only?
 
Thanks for the responses. I presumed that the limitation was the buffer to card transfer speed due to the card being 90mb/s write. From some crude tests (raw files) i can get 7 seconds of shots before the buffer fills - when hammering the shutter - If i was to say get a 180mb/s card (expensive), then in theory I could get 14 seconds before the buffer filled on Raw - but I don't know if that logic holds.

To answer your question Lewis - no - my fastest card is 90mb/s but i could borrow someone elses to test i guess.

RE Smaller files, AH5168 and Tim - good call, I'll test on JPG tomorrow, although ideally I'd shoot raw, because i tend to shoot in fairly dark conditions and at fast shutter speeds, so want the comfort blanket of being able to play with the exposure
 
A_S said:
I can see some lexar cards that record at 120mb a second, but lets say my files are 25mb
Click to expand...

We can only assume that the m should be an M but what about the b in the file size? Card speeds are (usually) quoted in M(ega)b(its) per second but file sizes as M(ega)B(ytes).

An older thread suggests that JPEGs are slower to deal with than raw files since the camera needs to process them before writing them.
 
A faster card will give no benefit if it is already faster than the card interface in the camera.

Whether JPEG is faster or slower than RAW will depend on whether the image engine processes images faster or slower than the card interface can transfer them.
With most modern cameras, processing JPEGs won't slow the process down, so they are likely to be faster simply because there is less data to transfer.
 
CF card will give best results. Lexar Professional 1066x cards reportedly give the best write speeds for clearing the buffer, although you struggle to get much above 100Mb/s write speed.

Your other option would be to upgrade the body to a 1dxii or similar so you can go faster than a CF card will allow which will allow the buffer to clear extremely fast.

1DXi is still CF so you wouldn't gain much benefit other than a slightly higher buffer capacity and 12fps shutter rate, 1DXii is CFast (should get at least double the write speeds of CF) and 14fps.
 
A_S said:
RE Smaller files, AH5168 and Tim - good call, I'll test on JPG tomorrow, although ideally I'd shoot raw, because i tend to shoot in fairly dark conditions and at fast shutter speeds, so want the comfort blanket of being able to play with the exposure
Click to expand...
MRAW?
It'll be smaller files than RAW but slower than JPEG - you get your comfort blanket at the cost of files that won't blow up to A1
Also faster CF cards are cheaper than trying to squeeze the best out of SD
 
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billgatese30 said:
CF card will give best results. Lexar Professional 1066x cards reportedly give the best write speeds for clearing the buffer, although you struggle to get much above 100Mb/s write speed.

Your other option would be to upgrade the body to a 1dxii or similar so you can go faster than a CF card will allow which will allow the buffer to clear extremely fast.

1DXi is still CF so you wouldn't gain much benefit other than a slightly higher buffer capacity and 12fps shutter rate, 1DXii is CFast (should get at least double the write speeds of CF) and 14fps.
Click to expand...

Yes, the camera's fastest bus speed is around 102MB/s, there will be little difference between a 1066X card and a 600X card, which will be about 130% of the speed of a very fast SD card.
 
Thanks all

This has been really helpful. I'll have a look at the Link posted by @Phil V In due course - but it seems I am limited by the camera not the card in this case, so JPG or Mraw is an option, unless i can get one of the UDMA 7 cards mentioned in the link it seems...although looking at the initial test results it doesn't seem much of an advantage. I'll read on
 
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A_S said:
Thanks all

This has been really helpful. I'll have a look at the Link posted by @Phil V In due course - but it seems I am limited by the camera not the card in this case, so JPG or Mraw is an option, unless i can get one of the UDMA 7 cards mentioned in the link it seems...although looking at the initial test results it doesn't seem much of an advantage. I'll read on
Click to expand...
The old CF bus is faster than the SD one.
This was common knowledge at the time.

And it’s the reason the standard SD card architecture has been ‘upgraded’ a couple of times.
 
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Phil V said:
The old CF bus is faster than the SD one.
This was common knowledge at the time.

And it’s the reason the standard SD card architecture has been ‘upgraded’ a couple of times.
Click to expand...


Yes, very simply CF can transfer 4X as much data every clock cycle (bit width 4-16 vs 1-4) (there are additional factors like addressing that help as well)

For me, the only bad thing about CF was bent pins, I have never had it happen, but have seen it many times, enough to make me careful every time I put one in :)
 
Sangoma said:
Yes, very simply CF can transfer 4X as much data every clock cycle (bit width 4-16 vs 1-4) (there are additional factors like addressing that help as well)

For me, the only bad thing about CF was bent pins, I have never had it happen, but have seen it many times, enough to make me careful every time I put one in :)
Click to expand...
I've only ever had it on a cheap card reader which didn't give the card very good support on the way in. Never had an issue with a camera as the slot is usually a very close fit to the card dimension to guide it in correctly.
 
Phil V said:
See this - and buy a CF card
Click to expand...
Thanks for sharing that Phil.... my D500 fills up faster now that I use UHS-II cards in the SD slot rather than the UHS-I Extreme Pros (with CF E Type B in the XQD slot)...so paying the extra for 'better' SD cards is not worth the extra expense reading into that comparison.
 
Sangoma said:
For me, the only bad thing about CF was bent pins, I have never had it happen, but have seen it many times, enough to make me careful every time I put one in :)
Click to expand...
I had it once in an Olympus E20 but I somehow managed to straighten the pins involved.

Don't ask me exactly how I did it, although I do recall the liberal use of impolite language and a laser pointer! :thinking:

Olympus E20.jpg
 
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