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Messages - dolina

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240GB Crucial M500 with firmware MU03 on a 2010 13-inch Macbook Pro with Superdrive through SATA 3Gb/s (300MB/s) interface. Clean install of 10.9.1 + other updates. TRIM not enabled as it was recommended by a Crucial employee that the built-in Garbage Collecting is sufficient.

240GB Crucial M500 in 2010 13-inch Macbook Pro by, on Flickr

I was able to source a 2nd HDD bracket so I can make a Fusion Drive.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: February 05, 2014, 03:05:54 AM »
It appears that I may be in error. By using PCIe 3.0 overhead is largely reduced or even eliminated to allow for ~2GB/s.

But then again we are talking about a spec rather than practical application.

I just installed a 240GB Crucial M500 SSD onto a 2010 Macbook Pro with a SATA 3Gb/s interface. Feels like having a new computer all over again!

I could imagine how it'll be like with 10x or so faster data transfers. ^_^


My point is the transfer rate does not change. It is kind of like ethernet..... packets are sent at the same speed.... it's how many packets per second that gives you the transfer rate.  A fast memory card and a slow memory card both transfer data at the same block speed. A faster memory card is ready sooner with the next block and that's what makes it faster.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: February 03, 2014, 01:17:24 PM »
What people care about are read/write speeds. Rare if you ever see anyone talk about block transfers.

Yes but the transfer rate and the throughput rates are different. If we assume that they are using block transfers, the transfer rate is 2GB/sec. That rate remains the same no matter what the read or write speed of the card is....

For example, if the read rate of the card is 200MB/sec, the data is transferred in pulses of 2GB/sec... the line is only active 10 percent of the time. Get a 500MB/sec card and the data is still transferred in pulses of 2GB/sec, but the pulses are more frequent and the line is now active for 25 percent of the time.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: February 02, 2014, 04:49:16 PM »
Is the transfer synchronous (8 bits per byte and no framing) where 16Mbits/sec = 2Mbytes per second?
Is it asynchronous (8bits per byte plus 2 framing) where 16Mbits/sec = 1.6Mbytes per second?
Is it asynchronous block (256bytes of 8 bits per byte plus 8 bits framing) where 16Mbits/sec = 1.9998Mbytes per second?
Based on industry practices it appears that they are quoting raw throughput.

See explanation contained

790-800MB/s is achievable using a PCIe SSD but no one can hit 768MB/s with SATA 6Gb/s SSD.

That is how I came about 1.6GB/s ceiling for a 16Gb/s SATA Express SSD.

I do not expect SATA Express SSDs that are below $1/GB @ 1.6GB/s sequential read/writes in 2014 based on this 2008 headline. It took them more than 5 years to get a $1/GB @ faster than 500MB/s sequential read/writes out the door. I would expect mainstream SATA Express SSDs by 2020.

Maybe by then 4K resolution *IPS displays will cost less than $1,000. The ones being peddled now at below $2,000 are TN displays.

Animal Kingdom / Re: Show your Bird Portraits
« on: February 02, 2014, 03:30:04 PM »
lion rock I do hope your camera insurance covers accidents.

Canon EF Prime Lenses / Re: Canon EF 24mm f/1.4L II USM
« on: February 02, 2014, 04:59:21 AM »

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: February 02, 2014, 04:58:56 AM »
I account for overhead. SATA 6Gbps would be 768 MB/s but no SSD I know off can consistently hit 600MB/s whether read or write.

Serial ATA International Organization interpreted 16Gb/s of SATA Express to 2GB/s. I would more likely believe 1.6GB/s to cover overhead.

I am also speculating where future unannounced versions could lead to.

XQD and CFast are based on PCIe and SATA technologies. As such are restricted by the same limitations. Like SATA rev 3.0 peaks at 600MB/s and PCIe rev 3.0 peaks at 800MB/s.

You're being a little imprecise there.  PCIe peaks at 985 MB/s of bidirectional bandwidth per lane.  However, PCIe allows you to aggregate (bond) up to 32 lanes.  An x32 PCIe bus, therefore, maxes out at almost 16 gigabytes per second in each direction.  Mind you, XQD currently provides only a single lane, but you could trivially turn it into a much faster standard just by throwing enough additional pins at the problem (four extra pins per lane, ignoring any ground pins that might be required to prevent crosstalk).

For a data card standard, unless I'm missing something, you could easily do away with all but three of the first 22 pins in the PCIe standard (the two SMBUS pins and one 3.3V rail).  The next 14 would probably be required, though perhaps not all of the grounds.  So you're at about 17 pins for the first lane, and possibly fewer.  If you then add more lanes using the same ground-opposite-data scheme that PCIe connectors use, add 8 pins per additional lane.

So if you used the same 50-pin connector that CF cards use, for example, you ought to be able to do 4x PCIe with nine pins to spare (assuming that you either require everything to do 4x or require the mode to be negotiated over the SMBUS instead of using detect pins).  If you use those nine pins as detect pins in some particularly smart way, you might even be able to achieve backwards compatibility with CF in both directions....

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 05:00:40 PM »
Rereading it appears that SATA Express uses PCI Express to achieve 16Gbit/s throughput.

Perhaps this is why everyone but Sony & Nikon abandoned XQD.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 04:12:38 PM »
Canon cameras not memory cards. ;) Unless of course ARRI and Phase Ones also make their own memory cards.

The limitation is indeed the mirror hence Canon going TLR-like.

Or as you mentioned a global shutter would work as well.

1DX benefits from the buffer and UDMA 7 CF cards.

I didn't think Canon manufactured memory cards. Maybe rebranded, sure.

Anyway, I thought part of the limitation on FPS was the shutter & mirror. I'd think that on a 1DX they have pretty big memory buffers, yet they can't speed up the shutter. If they actually can get a real global shutter on the next line of sensors, they could really pump things up as they would no longer be reliant on physical mechanisms.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 04:06:25 PM »
Amusing thread.

Fir of all, if it is a Q3 release, my vacation at the end of Q2 beginning of Q3 will have to live with the 7D and 50D I currently own, and that sucks.

Secondly, if it is a Q2 announce and Q3 release, prototypes are not a word used at this point. There might be some firmware changes between cameras. But these would be Beta or pre-production cameras.

As far as problems writing to the CF cards, those issues should be long found in regression tests and such. I would hope. I would expect bugs will be a minimum, there will be some. But I would also expect any photographer to have a few 1000, or more exposures on any new camera before they head to the sporting event, no?

Like seriously, who would grab a new camera and the start taking event pictures, unless you absolutely had to??

just say'n.

I have been in production development for a while now, and unless Canon is an absolute broken mess of a large corporation, I would expect there is significantly less risk with than some of y'all think. I have to expect these cameras have already been vibe-table tested with accelerated aging tests, temp testing for both environmental use, but again accelerated aging tests, regressions tests, life tests and so on.
Often times it is a job requirement imposed by the photoagency or directly with Canon itself.

Any who SATA Express and PCIe 4 (both 1.6GB/s) will come out by 2017 with Intel Skylake.

2017 4K resolution 32-inch iMacs anyone?

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 03:07:38 PM »
From what I've read Sandisk, Arri, Phase One, Lexar and Sandisk support CFast 2.0.

XQD was developed by Sandisk but not manufactured by them. Lexar and Sony are the sole XQD memory card makers and Nikon D4 the sole camera supporting it. Some months ago BH Photo claimed that Lexar discontinued XQD but Lexar rebukes this.

Only XQD you can buy off BH is from Sony.

CFast is not available on BH as of my writing.

My thoughts are the next 1D, 5D and possibly the 7D will support CFast if they start allowing uncompressed video straight to internal memory card or 4K resolution recording.

CFast would also be required if Canon were to adopt a TLR-like technology to attain higher continuous RAW fps. As I see it memory card read/writes are the main culprit holding back cameras.

XQD and CFast are based on PCIe and SATA technologies. As such are restricted by the same limitations. Like SATA rev 3.0 peaks at 600MB/s and PCIe rev 3.0 peaks at 800MB/s.

Next step up has both CFast and XQD peaking at 1.6GB/s. I think they will be updated once 8K resolution recordings become popular. In say 5, 10 or 15 years from now?

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 02:24:04 PM »
Alternatively Canon could go SDXC like what was done to the 60D and 6D. SDXC Version 4.0 allows for 312 MB/s using additional row of pins..

What I should be my worry now is to make sure the 5 CF cards are sold and I find the other 5 cards that I need to sell.

I really just want to have one memory card per body to keep things tidy.

Don't forget that CFast is Canon's preferred card format that they've been publicly backing - they'd be crazy to suddenly use XQD, especially since Nikon only has one camera that supports XQD so far, but Alexa is already supporting CFast via standard upgrades for most of their cinema cameras.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 01:57:15 PM »
If they're giving it out to pros, it'll be CFast. Or XQD. I haven't really looked at which one is superior, if either one really is. XQD is based on PCI-Express, while CFast is based on SATA. Either way, while they both support extremely high max speeds, those speeds will only be reached by very few cards, if ever. Until we get new technologies past flash memory. It's getting harder and harder to boost flash speeds, especially in such a fairly small & confined space. With current top end cards just starting to hit UDMA7 max speeds, XQD/CFast support is definitely needed on the next generation of pro cameras.

No one has max'd out CFast or XQD yet but they've surpassed UDMA 7 CF's 167MB/s limit.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 11:22:40 AM »
To be honest I was expecting the announcement for the 7D and 1DX replacement to have been made last October 2013.

EOS Bodies / Re: Canon EOS 7D Mark II in Q2? [CR1]
« on: January 31, 2014, 10:17:10 AM »
Canon lends out their prototypes to photoagencies and photogs they closely work with. Best time to organize such a test under real world conditions are at international sporting events like the World Cup and Olympics.

Canon & Nikon have both been doing this for decades to good effect.

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