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05-10-2015, 07:17 PM   #1
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Buying new SD cards for 645Z

I'm looking to buy some 256GB cards for my 645Z.

I currently use some Sandisk Extreme Pro cards with write speeds "up to 45mb/s".

I know the 645Z write speed is not so great that I can really take advantage of super high-speed cards, but will I notice a difference with a 90mb/s write card like the SanDisk Extreme Pro UHS-I SDXC U3:

SanDisk 256GB Extreme Pro UHS-I SDXC U3 Memory SDSDXP-256G-A46

Compared to getting another 45mb/s card, like the (substantially cheaper) Lexar 256GB Professional UHS-I SDXC:

Lexar 256GB Professional UHS-I SDXC Memory Card LSD256CBNL633

As a third option, is it worth considering this 60mb/s PNY card?

PNY Technologies 256GB Elite Performance SDXC P-SDX256U1H-GE B&H

The reviews are generally good, with a couple of complaints.

I've usually bought SanDisk just because... SanDisk (marketing dollars at work, I guess), but I've also had fine experiences with Lexar.

05-10-2015, 07:21 PM   #2
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ben, i just had those exact sandisks arrive 2 hrs ago, the 95mb/s ones - they are a huge leap up from the 40mb/s cards i had - it's made the 645z a lot more responsive and it only takes a brief time to write a file to the card after a shot. I can't speak for the 60's, but do recommend the 95's - they are great.
05-10-2015, 07:37 PM   #3
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QuoteOriginally posted by gavincato Quote
ben, i just had those exact sandisks arrive 2 hrs ago, the 95mb/s ones - they are a huge leap up from the 40mb/s cards i had - it's made the 645z a lot more responsive and it only takes a brief time to write a file to the card after a shot. I can't speak for the 60's, but do recommend the 95's - they are great.

Very helpful, thanks!
05-10-2015, 07:41 PM   #4
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Go for the extreme pro card. You won't notice much of a write speed difference compared to a Sandisk Extreme with a 45 Mb write speed, but you will compared to one of those cheaper Ultra cards. Plus, your PC card reader will thank you

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05-11-2015, 09:10 AM   #5
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I use the Sandisk Extreme Pro 95mb/sec 64GB (over 500 images per card) and it seems to write well with my images. Hey, it's 50MP so I expect a short wait, but then again the buffer seems to work fine even when many shots are taken in rapid succession, for example when I do landscape shots for later panorama stitching.

I just got a couple of the Sandisk Extreme Pro 64GB 280mb/sec cards to try out for travel. I got these because on far off travel my biggest time consumption is downloading my images for backup. After a busy day it can take forever. I know I am anal about this, but I prefer to have 2 backups plus the original camera 64GB SD cards. In addition I save jpegs to the second slot for quick previews back in the room if need be. This probably slows things down a bit, but I have no complaints even though I am using my slower Sandisk Extreme 30mb/sec SD cards for jpeg images.

I have these very small 128GB Sandisk Extreme Pro USB3.0 silver sticks that read/write at 260/240mb/sec. So that means my only bottleneck should be my notebook which in this example I use solely for through put from camera's 64GB card to the backup 128GB stick.

Forgot to mention I save as DNG in slot #1.

Last edited by algrove; 05-11-2015 at 09:21 AM.
05-12-2015, 04:58 PM   #6
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I used to buy Sandisk until I got some really good deals on the Lexar cards and have not looked back.

Here is what I am currently using: Lexar 64 GB 1000X - 150MB/sec you cannot beat this for price/performance.

I am very skeptical about using 250GB cards, if somehow the card is corrupted (I know, but it can happen), you've lost a ton of data. I prefer to use multiple 64GB cards instead. Each one of these will take about 850 .pef files and over 1100 DNG versions if you save it that way. Enough for a day's shoot in most instances. Or at least a single session.

I typically carry enough cards to cover my entire trip, and am also anal about backups. I carry two external USB3 HDs (2TB WD Passports) and every night I copy all the cards on to the two drives (easy enough in a single pass with a fast card reader and Lightroom). I then put the original cards (CF or SD) away. That way I have 3 copies of all my images. I put all the cards and USB drives in my carry-on baggage. When I get home, one USB drive is permanently put away (so I have the originals). At around $70 per drive, it is a small price to pay in the grand scheme of things.


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