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vohne

256GB SD on the T

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Hi guys!

 

Bought a PNY SD 256GB http://www.amazon.com/PNY-Elite-Performance-256GB-Speed/dp/B00FF90EZM

 

plugged it into the T, it gives me an option to format, I say YES, it just flashes the option again.

 

I say NO, it says can't read memory.

 

I went on the Leica site, they said the T is compatible up to 64GB sd cards. Does this mean my 256 can't work at all with it?

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Doesn't sound good for that size of card.

I'm more of a smaller size but many type, I have a couple of 16gb in my bag one in my wallet and one in the car. Would worry me too much having a large memory card and it failing.

I hope you find a way to use the 256gb on your T if you do let me know how many pics you can get on it I'd love to know.

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If they say that the card won’t work, it won't. Why on earth such an immense card? A bit like buying an ocean liner to go boating on the Thames...

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It is so important to have a 256GB card because it can only hold what, about 90,000 images? Goodness knows a person doesn't want to run out of space.

 

Some arithmetic can tell us how long it would take to review 90,000 images.

 

Oi! 256GB! Well, when we spend so much on a card, we expect it to be perfect in our expensive cameras.

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well the larger cards do make sense if video is important to you.

 

it does take special programming to support larger sized cards, so if Leica says it only supports up to 64 GB, you're probably out of luck.

 

if you know what you're doing, you might be able to partition the card, making a 64 GB exFAT partition at the beginning. but you'd only be able to use 64 GB (also not sure how the camera would deal with multiple partitions like that but seems like it might work).

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I went on the Leica site, they said the T is compatible up to 64GB sd cards. Does this mean my 256 can't work at all with it?

 

Yes it does mean that!  Seemples!

Edited by spylaw4

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Thanks for the responses guys.

 

I was aware that it could be a stupid question. It's actually for video and photos when we travel, and I think I also got hooked in by the discount.

 

Hmm, I guess I will just have to use it for something else, thanks everyone.

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Well, seeing that 32 GB card will hold about 2 1/2 hours of Video in full HD on my wife's Videocam  (from memory, I never touch the thing), I would suppose such a card would hold an awful lot of video footage - I shudder at the work of editing it....

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if you know what you're doing, you might be able to partition the card, making a 64 GB exFAT partition at the beginning. but you'd only be able to use 64 GB (also not sure how the camera would deal with multiple partitions like that but seems like it might work).

 

You may format an SD card as if were disc-like but they do not operate the same same way at all.

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You may format an SD card as if were disc-like but they do not operate the same same way at all.

 

What do you mean? it still has a partition map, so at this level it's pretty much the same.

 

I assume it just comes down to what the camera expects that partition map to contain. maybe if it sees a partition map that extends beyond addressable space (>64 GB) it'd balk; but maybe it's only checking to address the first partition it sees.

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What do you mean? it still has a partition map, so at this level it's pretty much the same.

 

I assume it just comes down to what the camera expects that partition map to contain. maybe if it sees a partition map that extends beyond addressable space (>64 GB) it'd balk; but maybe it's only checking to address the first partition it sees.

 

Formatting just sets one rule for allocating space. SD cards do not use typical disc methods.

Besides, how will you tell the camera which partition to use?

.

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Formatting just sets one rule for allocating space. SD cards do not use typical disc methods.

 

I'm still very curious, what do you mean by "SD cards do not use typical disc methods"?

 

Besides, how will you tell the camera which partition to use?

.

Yep, exactly the caveat I made twice..

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Hey so I just tested it out. Partitioned an SD card into a couple of partitions. The T just sees/uses the first partition.

 

So vohne, if you're comfortable with that kind of stuff you might be able to at least use your 256 GB as a 64 GB card with the T and not have to purchase a new card. Maybe. I don't have an SD card that large, so like I said before I'm not sure if it'll balk anyway.

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In the last published manual (internet) there is nothing to find about a maximum size for the SD card.

Does a in-camera-formatted 256GB card not work at all (no partitioning) ?

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I'm still very curious, what do you mean by "SD cards do not use typical disc methods"?

 

Simply that SD card protocols/methods are entirely different than, for example, fixed disc methods.

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Simply that SD card protocols/methods are entirely different than, for example, fixed disc methods.

I was just hoping you could enlighten me as to what the difference actually was since I'd love to know.

 

I spent time looking around and couldn't find anything to indicate there was actually a difference at this level. In hardware SD has a different (from say SSD) lightweight controller intended to work simply with USB, but once you get to the point of figuring out volumes it's the same as everything else (which, to be fair, is kind of the point of abstraction)—partition table in a boot sector, file systems on top.

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I believe is inproper for a moderator to make fun of anybody's request or need.

Why reputable companies allow this unacceptable behavior is inexcusable.

A highly sophisticated company and its equipment needs to be up to par and compatible with current product availability.

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I believe is inproper for a moderator to make fun of anybody's request or need.

Why reputable companies allow this unacceptable behavior is inexcusable.

A highly sophisticated company and its equipment needs to be up to par and compatible with current product availability.

 

First, welcome to the forum! I hope you enjoy your Leica T. I am sure the glitches will be worked out.

 

This forum is neither owned nor operated by Leica. It does have an ethical standard as outlined in this link: http://www.l-camera-forum.com/page/rules.html

 

Most of us are old enough to have rather robust senses of humor and you might read some good natured facetious posts from time to time.  Settle in, relax, enjoy. Again, welcome.

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I was just hoping you could enlighten me as to what the difference actually was since I'd love to know.

 

I spent time looking around and couldn't find anything to indicate there was actually a difference at this level. In hardware SD has a different (from say SSD) lightweight controller intended to work simply with USB, but once you get to the point of figuring out volumes it's the same as everything else (which, to be fair, is kind of the point of abstraction)—partition table in a boot sector, file systems on top.

 

(Warning notable oversimplifications below - I work on operating systems for a living and could go into way too much detail -- this is a layman's explanation.)

 

Disks are spinning media and they fundamentally they are made up of platters which are stacked up on each other on a spool, then divided into tracks which are further divided up into sectors. In the old old days the operating system actually specified a block by head, track, cylinder, and sector. It just got way to complicated and these days disks are just considered a linear series of blocks. The disk and its embedded controller maps those block numbers in some reasonable rational manner to locations on the disk. You can sort of know that block 2000 is very likely near block 2001 and so when you allocate a contagious range of blocks to store a file the disk is able to read or write them in a fast and efficient manner. And when I say "near" what I mean is that adjacent blocks are kind of timingly near each. They might be  on another platter or on a sector half way around the disk or something like that but if you read them in a linear manner the disk drive will not have too many problems following them around the disk. 

 

Flash like our little SD cards are totally different. They are randomly accessible in a very quick way. On a disk if you read block 2000 and then read block 10000 then go back to block 500 you are going to pay a timing penalty. On SSD that kind of thing is no problem. On disk the blocks have historically been 512 bytes, but have recently been expanded to 4096 bytes in some disk drives. First of all Flash has its own write width which isn't necessarily anything like 512 bytes or 4096 bytes. Inside the flash, it does its own thing. Also Flash has a limitation on the number of cycles that it can be written to each of its cells. So what the flash controller does is presents a linear series of blocks just like a modern disk drive. So since it can stick whatever it wants wherever it wants without paying a timing penalty for either read or write and because it has a finite number of write cycles on each of its cells what it does is tries to even out the wear on each of the cells. While doing this, it will also slice and dice up the data to optimize speed within its power budget. A little chunk of electronics might handle cells 1-100 and another chunk might handle 101-200 ... and so for optimal speed you want to spread the write across as many cells as possible simultaneously but you can only have 60 of them operating at one time or else you don't have enough power. In the end all the little controller in the SD card needs to do is keep track of which block is stored where in the flash.

 

Partitions are simply an offset added to a block number. So sector 2000 of the second partition may simply be block number 10,000,000 + 2000 or something like that. All the operating system designers have generally agreed on a couple of ways of storing partition tables on disks, it is just an agreement that basically everybody abides by. Some simple devices like the OS in the camera may keep things very simple and just assume that there is one partition. They read the very first entry of the very simplest form of a partition table and it says something like "add 18 to every block number for blocks in the first partition." The T doesn't pay attention to anything else. It doesn't give you a way to select a different partition. When you format a card, it writes the simplest form of the partition table, sets a label for the partition and then jumps right into the very simple FAT file system.

 

SD, MMC, SDHC, and SDXC are just specifications for how the camera communicates with the card. It defines things like power budget and how to specify block numbers to the card... IIRC MMC is long gone. SD is pretty much gone now too because it maxed out at 4GB. SDHC and SDXC are the current standards even though we still call everything SD cards.

 

SSD just means that whatever solid state (the SS) part pretends to be very much like a disk (the D) in other words it presents itself as disk controller and provides that linear series of blocks. When SSD is constructed out of Flash that SSD controller behaves very much like a SD card's internal controller does when it controls its Flash. Except while the SD card usually will have SDHC and SDXC as the interface standard to the controlling computer, SSD will usually have SATA on the interface to the computer side. We're not going to go into what SATA is. Just accept that it is the language that most current disks talk.

 

USB is a big topic and I don't want to go into it and it has nothing to do with this as far as I can tell except that you can put a SSD on the other side of a chip which implements the USB protocol for a disk. Then your computer will send SATA disk commands to its USB controller which will send them to that chip which will strip off the USB part and send them to a SATA chip which will then convert them into its internal Flash reads and writes.

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Thank you, bencoyote. That was a good explanation.

 

Just to add a couple things of minor interest: SDHC cards usually have a capacity above what is designated, however only what is designated is used - the manufacturing error ratio for SD cards is very high; usually over 30% of the allocatable cells are defective. We are not being cheated. We can use all the space advertised. There is a separate part of the card in which the cells are assured to be good and those cells are used to map bad blocks of the card. You and I cannot get to them, but counterfeiters can, and do so that they change the apparent size, which fails when the host tries to use the nonexistent space.

 

When a person overwrites the whole card it wears the card fmore than simply using it with a quick format. As bencoyote wrote, it uses a load-balancing strategy to use blocks randomly rather than using each one over and over. If it did not do load-balancing our cards would not last very long at all. (Oh, when we overwrite the whole card, we still do not get to the special area that records bad blocks, etc.)

Edited by pico

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