Dual micro SD to SD card adaptor for redundancy. Anyone have industry contacts for this one?

David - Sydney

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Dec 7, 2014
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I posted this deep in another thread but thought it made some sense to add as a new one....

Micro SD cards are harder to handle but you can get UHS II and 512GB versions so technically no performance hurdle. Would you buy a dual card adaptor for your single slot camera if redundancy is important but not critical to warrant 2 R bodies?

The Sony Pro Duo memory stick was/is so expensive that there are adaptors for 2 x micro SD cards in one pro duo card. These are quite old now and only used as sequential/additional memory ie not mirrored/redundant
Pro duo dimensions are slightly physically smaller than a SD card so in theory a SD adaptor could hold 2 x Micro SD cards giving us the infamous dual SD card redundancy. SD card 32x24x2.1mm vs Pro duo 31x20x1.6mm vs Micro SD 15x11x1mm

There are a couple of threads discussing the option below. Summary is:
- Possible to do technically.
- Additional points of failure but would solve the failed card scenario.
- Could increase the latency.
- Could be much more complex/power etc if a RAID server/buffer is the solution vs a FIFO solution.
Nothing on the market at this time but I imagine that there would be some pent up market demand for such a product and probably more than a pro duo card market

In the bad old film days with underwater photography, if you wanted >36 shots you needed 2 bodies + housings (strobes) for additional storage or redundancy against flooding!
 
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Mt Spokane Photography

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Mar 25, 2011
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I don't like micro sd cards, but have to use them in my phone and tablet. I've always thought of them as slow, but I really don't know. I would not buy such a adaptor, but some might. I wonder how it would work, if I put it in a card reader?
 

David - Sydney

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Dec 7, 2014
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I don't like micro sd cards, but have to use them in my phone and tablet. I've always thought of them as slow, but I really don't know. I would not buy such a adaptor, but some might. I wonder how it would work, if I put it in a card reader?
they are certainly small cf SD cards. I would suggest using a separate card reader or single micro->SD card adaptor for read back PC. Then again writing to the dual cards but read would be from one card (eg for reviewing shots). Which card would be the read one is interesting... In my 5Div with dual SD/CF cards, I am not sure which is read for the reviews. If setup as sequential then both, if split by photo/video then each would be read depending.
 

Mt Spokane Photography

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Mar 25, 2011
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they are certainly small cf SD cards. I would suggest using a separate card reader or single micro->SD card adaptor for read back PC. Then again writing to the dual cards but read would be from one card (eg for reviewing shots). Which card would be the read one is interesting... In my 5Div with dual SD/CF cards, I am not sure which is read for the reviews. If setup as sequential then both, if split by photo/video then each would be read depending.
On the 5D MK IV, you set the card to write and to play back. You could not do that with a dual card adapter, the camera firmware for a single card camera would not know what to do.
 

David - Sydney

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Dec 7, 2014
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A
On the 5D MK IV, you set the card to write and to play back. You could not do that with a dual card adapter, the camera firmware for a single card camera would not know what to do.
Agreed... but the 5Div already has dual slot. You could always have 2 x dual micro SD for 4x redundancy though. A camera with a single slot can only point to the card in it. A dual micro SD adaptor would appear to the camera as being a single card.

A dual micro SD adaptor would default to one of the mirrored micro SD cards as being the primary read card. It could be the only card installed ie if both aren't filled (preferable) or default to a primary location.
 

YuengLinger

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Dec 20, 2012
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If the storage medium is too small, it would get lost too easily. I went to an Arthur Morris workshop. The only sensible advice I took away from it was this: "You might worry about having too many images on your card, but I've found that photographers drop and lose their CF cards often--sometimes in mud--but I've never seen one fail in all my years with digital."

Now, I'm not claiming what he says can't be challenged by statistics, but I really understood what he was getting at. And he was talking about CF cards, not even SD cards. A Micro SD card in the field? At any event or in a natural setting? Heck, I'm constantly looking for my "watch, wallet, spectacles, and t________s." (Austin Powers fans can fill in the blank.) Trying to fiddle with a micro-SD card in low light or when in a rush? And if I drop it? Holy smokes!
 

David - Sydney

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Dec 7, 2014
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If the storage medium is too small, it would get lost too easily. I went to an Arthur Morris workshop. The only sensible advice I took away from it was this: "You might worry about having too many images on your card, but I've found that photographers drop and lose their CF cards often--sometimes in mud--but I've never seen one fail in all my years with digital."

Now, I'm not claiming what he says can't be challenged by statistics, but I really understood what he was getting at. And he was talking about CF cards, not even SD cards. A Micro SD card in the field? At any event or in a natural setting? Heck, I'm constantly looking for my "watch, wallet, spectacles, and t________s." (Austin Powers fans can fill in the blank.) Trying to fiddle with a micro-SD card in low light or when in a rush? And if I drop it? Holy smokes!
a Micro sd card wouldn’t be removed From the adaptor unless there was a failure. Even then the other micro sd card would still work until you are back in a reasonable environment for replacement. The sd adaptor could remain in place for ever in theory if you were transferring files via usb (or wireless!). I couldn’t foresee a scenario where the micro sd card would need to be removed in the field but happy for feedback
 
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YuengLinger

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Dec 20, 2012
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a Micro sd card wouldn’t be removed From the adaptor unless there was a failure. Even then the other micro sd card would still work until you are back in a reasonable environment for replacement. The sd adaptor could remain in place for ever in theory if you were transferring files via usb (or wireless!). I couldn’t foresee a scenario where the micro sd card would need to be removed in the field but happy for feedback
So camera companies would be expected to write firmware for these adapters? Otherwise how would we choose how to use two at a time? (I don't believe you clearly addressed this key issue in response to Mt. Spokane's post.)

If so, I think some big name SD players would need to be involved, not just some clever entrepreneurs selling stuff on ebay.
 
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SteveC

M50 & T6i
Sep 3, 2019
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If the storage medium is too small, it would get lost too easily. I went to an Arthur Morris workshop. The only sensible advice I took away from it was this: "You might worry about having too many images on your card, but I've found that photographers drop and lose their CF cards often--sometimes in mud--but I've never seen one fail in all my years with digital."

Now, I'm not claiming what he says can't be challenged by statistics, but I really understood what he was getting at. And he was talking about CF cards, not even SD cards. A Micro SD card in the field? At any event or in a natural setting? Heck, I'm constantly looking for my "watch, wallet, spectacles, and t________s." (Austin Powers fans can fill in the blank.) Trying to fiddle with a micro-SD card in low light or when in a rush? And if I drop it? Holy smokes!
I expect you'd never remove the micro SD card from the adapter. (The only time I remove mine is when I'm trying to see what kind of card it is--capacity, speed, all the other gobbledygook they print on the thing in a font so tiny I need a magnifier. That's never under field conditions.) That'd likely be true with this hypothetical dual adapter, too, with the added wrinkle that you would have an extra reason to remove the card (hopefully under non-field conditions) if one fails.

Nonetheless, I can imagine photographers dropping the adapter as a whole off a cliff and thereby being the single point of failure that eliminates BOTH cards.
 

David - Sydney

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Dec 7, 2014
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So camera companies would be expected to write firmware for these adapters? Otherwise how would we choose how to use two at a time? (I don't believe you clearly addressed this key issue in response to Mt. Spokane's post.)

If so, I think some big name SD players would need to be involved, not just some clever entrepreneurs selling stuff on ebay.
Can’t see camera OEMs writing firmware for this. The adaptor must look like a normal sd card but write to 2 micro sd cards Just like the pro duo adaptor. We can think of a similar situation as RAID0 configuration but drastically simplified.
The micro sd cards would need to be formatted first. One way would be to use a single micro sd card adaptor (available everywhere now). All firmware and (probably FIFO circuitry rather than server-on-chip) electronics would be on the dual adaptor
 

SteveC

M50 & T6i
Sep 3, 2019
382
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Can’t see camera OEMs writing firmware for this. The adaptor must look like a normal sd card but write to 2 micro sd cards Just like the pro duo adaptor. We can think of a similar situation as RAID0 configuration but drastically simplified.
The micro sd cards would need to be formatted first. One way would be to use a single micro sd card adaptor (available everywhere now). All firmware and (probably FIFO circuitry rather than server-on-chip) electronics would be on the dual adaptor
Presumably you;d want RAID 1, not RAID 0. Raid 1 is the mirroring that people here are hoping this will do; Raid 0 stripes, so that if one card goes out, they're both FUBARed. That's riskier than the situation that already exists because it's twice as likely to trash your pictures as a single card would be.
 
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