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Old Sep 25, 2005, 10:49 AM   #1
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I thought the better cameras use the CCD capture device? And usually have a higher Capture bit depth. Like 16 or more?

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Can anyone explain why the Canon EOS 1Ds is $8,000 uses the older kind of capture device (CMOS) and the ADC-analog to digital converter is only 12-bit?
http://www.dpreview.com/reviews/canoneos1ds/


Yet a Sony DSC F828 has a 16-bit CCD capture device, and is only about $900. not to mention a killer Carl Zes lens.
http://www.dpreview.com/reviews/sonydscf828/


Is there is something I'm getting mixed up?




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Old Sep 25, 2005, 11:23 AM   #2
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Nothing is getting mixed up. CCD had been around for a long time and used to be quite a bit BETTER than CMOS. CMOS, is in fact the "new kid on the black."

It first came out commercially about five years ago and has steadily improved unitl there is little difference between their ability to capture images.

It's great advantage over CCD, is that it uses quite a bit less power. Thus you get more bang for your battery. CCD is still dominant in scanners, because they plug into your wall outlet. Both can shoot in 12 bit, which gets translated up or down in to 16 or 8 bit respectively. I don't believe there's much difference in the cost of manufacture.

Probably (and don't quote me on this) but the reason Canon's Mark II 1Ds costs so much is that their sensor is not maufactured in huge amounts. Or, who knows, maybe they're being greedy?

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Old Sep 25, 2005, 3:57 PM   #3
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I see thanks DBB

I've just read something like that so I see what you mean.



However, what about the capture bit-Depth? That is one of the most important things is capturing accurate light. The canon only uses a 12-bit while the Sony uses a 16 bit.


That's a big difference.
When I asked if I my have mixed somethingup: the Capture bit-Depth numbers is what I was referring to.
-Canon 14-bit's per alpha channel
-Sony 16-bit's per alpha channel




Even if the CMOS is more efficient and harder to produce, the simple fact this one only captures 14-bit per channel doesn't justify a $7,000 dollar difference.

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Old Sep 25, 2005, 7:26 PM   #4
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Could you please give a link to the camera that uses that Sony sensor? I've never heard of that sensor (but then again, I don't really keep up with that stuff... not until it's time for a new camera.)

That could really help dynamic range in the images a huge amount! And that is something I want to know about. Maybe Sony has "announced" it, but it isn't in use?

My understanding of the reason for some of the high cost of the 1Ds MkII is two fold:

It is hard to make a perfect sensor and the physically larger the sensor the more money you throw away when there is a manufacturing defect. So there are more places to have a defect (larger sensor, more photosites) and it costs them more money when they have to get rid of it. In technical terms, it means there is a lower yeald and therefor higher costs.

The second reason is that a photosite (the part of the sensor which actually samples the light) requires the light to be entering the photosite as an angle closer to perpendicular than film does. What this translates into is that a set of micro-mirrors must be used to "strighten" out the light (bend it closer the perpendicular) for the photosites closer to the edges of the sensor. Those mirrors are a cost that smaller sensors (like on the 20D, and I think the 1D MkII) don't have.

Now, since the 5D has been announced, and it will use a full-frame sensor, I assume that Canon has gotten good enough at making the full frame sensors that they can sell the camera at a cheaper price (it doesn't hurt that they removed other features from the camera as well... the 5D is a "lesser" camera than the 1Ds MkII, but it is in more ways than just a lower resolution sensor.)

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Old Sep 25, 2005, 7:48 PM   #5
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Hi Eric, Are we talking about the same camara here?
I'm refering to the Canon EOS-1Ds


Both links are at the top, on the first post.

The first link is the Canon I'm referring to and the second link is for the Sony DSC717



I see what you mean but $7,000 is kind of huge don't you think?
Who the heck is going to spend 7 thousand bucks more when the spec's don't match up.
There must be something special about the Canon.




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Old Sep 25, 2005, 9:12 PM   #6
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Starstreams wrote:
Quote:
There must be something special about the Canon.
Well, that's what they'd like you to believe.
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Old Sep 26, 2005, 8:21 AM   #7
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Starstreams wrote:
Quote:
I see thanks DBB

I've just read something like that so I see what you mean.



However, what about the capture bit-Depth? That is one of the most important things is capturing accurate light. The canon only uses a 12-bit while the Sony uses a 16 bit.


That's a big difference.
When I asked if I my have mixed something up: the Capture bit-Depth numbers is what I was referring to.
-Canon 14-bit's per alpha channel
-Sony 16-bit's per alpha channel




Even if the CMOS is more efficient and harder to produce, the simple fact this one only captures 14-bit per channel doesn't justify a $7,000 dollar difference.
The links you posted don't work, so I can't comment

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Old Sep 26, 2005, 2:51 PM   #8
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The Canon 1Ds is no longer made, and can be purchased used for a lot less than $8,000 (ebay has them for 4,000.) It has been replaced by the 1Ds Mark II (often written as 1Ds-MkII or 1Ds MkII or 1Ds II.) Its replacement is still $7,400.

First one clarification point. The F828 has a 14-bit sensor, not 16-but, as you suggest. Read page 6 of Steve's review of the camera. It is still more than the 1Ds or the 1Ds MkII, so in theory it should have more dynamic range.

But that isn't your point. The reasons for the extra cost are HUGE... but for most people doesn't matter and therefor aren't justified. I think its also over priced (i.e. their profit margin is too big) but who am I to really say? My only input is not buying the camera!

The 1Ds is a "Professional" grade camera. It does way more than the vast majority of people care about or will ever use. But if you need it, then you need it. I could buy a Toyota car, or I could buy an SCCA street legal race car. Both would get me to work in basically the same amount of time (obeying the speed limits) but one would cost *way* more than the other. For the vast majority of people the race car would be completely wasted on them, but for a few people (people who race cars) it is exactly the right tool for the job.

The 1Ds has more resolution (11.1MP vs. 8MP.)
The 1Ds is water proof. Truly, it is. People have put them in showers and then used them without drying them off.
The 1Ds has better auto focus and more AF points.
The 1Ds (probably) has lower shutter lag.
The 1Ds has way more customizations that can be made.
The 1Ds has a body that can withstand way more abuse and still work.
The 1Ds has a shutter that is rated at way more actuations.

There are more differences than that, but hopefully you get the idea. The 1Ds is made for someone whom the F828 isn't good enough. I, for one, would not buy an F828. It would cost me pictures. I also wouldn't buy a 1Ds (too expensive.) But I will buy the replacement to the 1D MkII when it comes out. It will cost me around $4,000 but it should actually let me get shots than I can't get with the 20D right now.

Does that help?

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Old Sep 26, 2005, 7:48 PM   #9
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First off Thanks to all of you, that was basically my question.
I have a lot to learn. I've never even heard of cross talk in cameras.

And I don't get how the mm sizes work where you mentioned the sensors.
Anyway, you've given me something to at least go off of and look into.
I think I need to read more reviews to learn this stuff.
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Old Sep 26, 2005, 8:53 PM   #10
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:-)
The mm (millimeters) is just a length; 1 mm is about 1/32 of an inch.
So the Sony sensor is a rectangle about 1/4 inch by 11/32 inch in size.

The Canon sensor is a rectangle that is 30/32 inch by 46/32 inch, (about 1 inch by 1.5 inch).

The larger the sensor the less densely packed the photosites can be and each photosite can be larger.

This gets you 2 things:
  • The larger the individual photosites are the more light they can absorb; this translates to a more sensitive the sensor. Which shows up as higher available ISO's on the camera, ISO 3200 is available or even ISO 6400 might be possible on some cameras. [/*]
  • The lower photosite density on the larger sensor reduces false photosite triggering. On a very densepacked sensor a blob(tm) of light hitting one photosite may cause the neighboring photosites to trigger. A phenomenon which I beleive may be called blooming. [/*]
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