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Messages - kaihp

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16
EOS Bodies / Re: Do you have a 4K display?
« on: December 20, 2013, 04:41:11 PM »
But profits are only attained when the consumer seesthinks there is a benefit.

There, I fixed it for you  ;)

I will seriously consider a 4K monitor when it comes down in price .... not necessarily for photos, but for the need of "screen real estate" for general usage. I was recently comparing a UHD TV vs a FHD TV for work (as a replacement for a projector), and the ability of the UHD to do render more details just for text etc was quite convincing.
The RMB19,000 price tag for the 65" version kept me at bay, though.

 

17
Included:
--A pouch of reasonable quality -- Seems to be woven nylon, neoprene lining, a touch of pleather trim, velcro

By the picture, the pouch looks much like my genuine Canon ST-E3-RT pouch. I will probably buy the YN-E3-RT when I'm back in China and do some back-to-back comparison. I am not, however, going to do a teardown of the ST.

18
EOS Bodies / Re: Thinking Out Loud: EOS 7D Mark II Thoughts
« on: December 16, 2013, 04:37:44 PM »
is an aps-c sensor really cheaper to produce? You would think the 70d sensor with its smaller photo sites and dual pixel tech would be more expensive than the 6d sensor which is about the same mp count?


Pixel size doesn't matter significantly (as long as the density is achievable with the process scale being used (500 nm, 180 nm, etc.).  Area matters - you get a lot more APS-C sensors than FF from a wafer; the larger sensor also means a higher QC failure rate, raising the cost further.

I suppose that's true, I just don't think that it is the huge cost difference its made out to be and if its the sensors area and not pixel count is what makes it expensive then they should hurry up with the high mp ff sensor


Neuro's got it right here.

The silicon wafers used for IC and sensor fabrication have a fixed manufacturing cost per wafer*. So if you can get ten times the number of good parts out of a wafer, the part cost will be - everything else equal - 1/10th the original cost.

There are a couple of things that affect the actual yield of a wafer:
1. How many (rectangular) dies that can be put on the (round) wafer. The "square peg in round hole" problem. See Wikipedia. Plugging in some numbers for a 300mm wafer size, I get 1610/610 = 2.64 times more APS-C sensors than FF sensors.
2. Intrinsic die yield. This is usually modeled as falling exponentially with the die area, so an APS-C sensor will intrinsically have exp(1.62)~=13 times higher yield than a FF sensor. The yield is based on how likely fabrication defects will not impact a die of size X, with an inherent defect density of A0. The defect density is related to the fabrication line itself (it usually starts out high, and then improves over the lifetime of the fab line, as the engineers learn how to control and improve the process line).
3. Feature density. This reflects how dense the wires/transistors etc are, and will somewhat counteract the die yield above. I'll ignore this below, since I don't have data and this has never been significant enough for me to bother about when considering the yield of a particular product.

So for APS-C vs FF sensors, fabricated on the same line, a single 300mm wafer will yield ~2.64 * exp(1.62) ~ 34 times more good dies of APS-C size than of FF size.

I probably forgot a number of details in relation to the yield - apologies in advance for that - but hopefully this shows why an APS-C sensor will always have a cost advantage over a FF sensor.

As a reference, the cost of a processed 180nm wafer for mixed analog/digital designs can be on the order of USD2000 (ex fab cost). Lower geometry wafers are generally more expensive, higher geometry less expensive.

*) This assumes a number of technicalities, such as using the same fab options, metal layers, equipment utilization rates etc etc etc. To the first order and for this discussion, this is a good assumption.

19
Personally, I don't think whether DSLR is around in 10 years matters that much. If DSLR is dead, then it's because something superior has replaced it.

But what I think we can be pretty sure of, is that in 10 years there will still be bodies/sensors that can take EF lenses.

We as Canon's customers have far too much invested in EF lenses to be interested in giving up the EF mount lenses on such a (relatively) short term horizon.  Canon knows this, and will make sure that we are not overly tempted to abandon them (ie jump ship to, say, Nikon).

20
Canon General / Re: Sensor production
« on: November 29, 2013, 02:41:39 AM »
Intel's fabs are geared towards digital logic designs (processors, GPUs, chipsets, flash), not sensors.

Fabs are optimized towards specific uses, so trying to put a light sensor is not likely to be feasible. As an example, significant leakage currents can be accepted in a digital process, whereas the same leakage would leave an analogue circuit heavily compromised: A/D resolution, noise, dynamic range would all be impacted.

As Mt Spokane is pointing out, the digital IC are "tiny" - preferably below 100 mm^2. Compare this with the 864 mm^2 area needed just for the sensor array in a FF sensor (just the pad ring is likely to rack up another 25+ mm^2).

21
Yes but that will get you about as far as "no dear your bum looks big in everything!" :o
"Does my bum look big in this?"

"yes, you have a big bum!"
My Brazilian friend would take that as a compliment :)

cue the yearly "Miss BumBum" competition held there.

22
EOS Bodies / Re: Canon EOS 7D Mark II in 2014 [CR2]
« on: November 13, 2013, 11:19:46 AM »
With today's technology I'm sure they could redesign the battery bay to be smaller and carry a thinner battery that equals the power of about two LP-E6s and a slightly better voltage to drive the AF better than it's driven on the 5D mark III but not as good as the 1D-X.
Alas, we are up against physics here, so getting towards a ~ half-sized battery (compared to an LP-E6) is not very likely.

23
Lenses / Re: AFMA & distance?
« on: November 08, 2013, 12:11:50 AM »
In practice, I'd expect to see a difference with a +5 adjustment for an f/2.8 lens (but it would be barely perceptable for an f/5.6 lens, if at all).

FWIW, I found that an adjustment of +4 on my 70-200/2.8IS II made a very visible and significant difference. At some point, I want to get around to testing the 70-200 for how much the AFMA varies with target distance because I feel that the portrait-type photos I take don't seem to be sharp where I expect them.

24
DSLR's need to reinvent the CF card
The CF card has already been reinvented. It's called CFast and is based on the SATA standards (instead of the PATA/ATAPI/IDE interface).

25
Kids also swallow memory cards, coins, pins, clips, magnets in mobile phone covers/purses/wallets/camera bags/laptop bags etc and get serious problems, yet knowledgable photogrpahers, who work with the public, still carry/use them ... I do not think the two little magnets in the magmod will cause any serious problems to the public.


The problem with kids swallowing super strong magnets is real.  But it was mostly the Bucky Balls that caused most of the trouble.  Read this... http://www.cnn.com/2012/11/02/tech/web/apparently-this-matters-buckyballs/


The problem with kids swallowing almost anything is real too. Batteries, in particular (it's a patient/product risk in my line of business, so we provide child locks so they cannot get to the battery).

26
EOS Bodies - For Stills / Re: EOS 5D Mark III Firmware 1.2.3 Available
« on: November 03, 2013, 10:15:11 PM »
Is there a way to save the existing firmware out of the camera to support a future downgrade in the event the upgrade turns my camera 'pear shaped'? Also, does the upgrade wipe the camera settings or are they retained?

Admittedly I have only done an upgrade once with my 40D and it went well so there was no need to revert back to the earlier firmware.
If you had downloaded an earlier version, you can rewind back to that one. All the versions Canon puts out are complete. Unfortunately Canon USA has removed the firmware version 1.2.1 in the last two days.

These links might be useful:
https://dl.dropboxusercontent.com/u/27313056/eos5d3-v113-win.zip
https://dl.dropboxusercontent.com/u/27313056/eos5d3-v121-win.zip

27
Site Information / Re: new look for CR
« on: November 01, 2013, 05:33:55 AM »
I like the new look! Not sure about the blank horizontal gray bar though.

That's a space for banner ads - if you have ad blocking, it'll be blank.

One thing that has always annoyed me is the highlighted forum posts on the right hand side of the Home page. If you click on one, I find it annoying that it doesn't take you to the first post, but to some random place down the thread, often the bottom post. Can it not be fixed that it opens at the top of the thread?

On the other hand, there may be a good reason for this that I can't figure out...

It links to the most recent posts, not the first post in most recently active topics.  An easy (and often overlooked) way to access topics starting with the post after the last one you personally read (which is the first post, if you haven't read that thread) is from the upper right corner of the forum pages.

Well, I for one can't see the point of that - if it's a new thread, I want to read it from the top, not navigate all the way back. And "upper right corner" - darned if I can see what you're referring to - must be blind!

If you click on the subject of the thread, you'll be sent to first posting. If you click on the "NEW" icon, you'll be sent to your first unread posting.

Personally, I would really appreciate if CR could go away from red-on-black, due to the bad contrast makes it difficult for me to read the text (esp. the "Show unread posts since last visit" and "Show new replies to your posts" lines)

28
Lenses / Re: Photos from 200-400. Also any comments...
« on: October 28, 2013, 11:46:47 PM »
Eldar & Edward,

Maybe the Manfrotto Belt pouch is the right thing for you?


Should be available from several sources like Amazon, B&H, ...

Regards,

Kai

29
Software & Accessories / Re: I think I may want a Monopod
« on: October 26, 2013, 12:05:51 PM »
I've found (after being tipped off by an English car/motorcycle pro photographer) that using a head like the Benro DJ-80 makes the monopod much more versatile, especially when combining it with a Belt pouch.

Attaching the monopod to yourself allows you to pivot around yourself with getting the monopod's pivot point in your way.

30
Lenses / Re: Focus issues with 600mm f4 is ii
« on: October 26, 2013, 11:56:37 AM »
At the risk of asking an obvious question: did you use mirror lock-up with the shutter release and what was the delay?

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