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propwash
08-31-2004, 09:40 AM
I am a little confused regarding the manufacturer's specifications for CCD's. I have seen something like "this camera has a 1/1.8" CCD." What do they mean by the improper fraction 1/1.8? mathematically speaking, 1/1.8 is the same as 0.5555555....

Do the two numbers in the specification mean two different things, or are they both used in the physical description of the CCD?

Thanks in advance for any help you might give me to help clear up my confusion.

mikeS
08-31-2004, 10:28 AM
Hi propwash

have a look at http://www.dpreview.com/learn/?/Glossary/Camera_System/Sensor_Sizes_01.htm for an explaination.

propwash
08-31-2004, 10:35 AM
Thanks for the quick reply. That link helped to explain a lot! My original impression seems to be right--it is a fraction, but for some reason they have decided to keep the improper fractions rather than simplifying them. Thanks again.

PixChick
08-31-2004, 12:09 PM
What do they mean by the improper fraction 1/1.8? mathematically speaking, 1/1.8 is the same as 0.5555555....


I know this doesn't really have to do with your question, but I am a former math teacher and have to comment...

1/1.8 is not an improper fraction. In an improper fraction, the numerator is greater than or equal to the denominator, as in the fraction 4/3 or 5/5. An improper fraction will be a number equal to or greater than 1 when converted to its decimal equivalent.

Again, sorry this isn't really an answer to your question but like I said, as a former math teacher, I couln't let it lie. Hope I didn't offend.

PixChick :)

mikeS
08-31-2004, 12:17 PM
It's also the way that the bookies in some parts of the world express the odds. We have the good old 7 to 4, 3 to 1 system here.

Anyway a quick question that's tenuously linked to this thread and pointedly about the difference between the conon a80 and a85.

a80 has a 1/1.8 sensor.

a85 has a 1/1.2 sensor.

does anybody know which is the better camera?

D70FAN
08-31-2004, 04:40 PM
It's also the way that the bookies in some parts of the world express the odds. We have the good old 7 to 4, 3 to 1 system here.

Anyway a quick question that's tenuously linked to this thread and pointedly about the difference between the conon a80 and a85.

a80 has a 1/1.8 sensor.

a85 has a 1/1.2 sensor.

does anybody know which is the better camera?

A85 spec = 1/2.7 sensor according to Canon.

mikeS
09-01-2004, 08:52 AM
Well spotted George! Sounds like you have the inside track there at canon.

Any other observations regarding the relative merits of the two cameras in question?

D70FAN
09-01-2004, 11:06 AM
Well spotted George! Sounds like you have the inside track there at canon.

Any other observations regarding the relative merits of the two cameras in question?

Nope, in fact my digital cameras are Nikon (CP990 & D70) and Sony (DSC-S85) to this point, although I have seriously considered adding the A75 and Panasonic FZ10 to the stable. The probem is that I can't justify buying new cameras every 6 months.

It appears that the A85 is using a smaller area 4MP sensor (1/2.7 vs. 1/1.8) for the A85 which leads me to believe that higher ISO pictures will be noisier. Additionally, 4 MegaPixels (A80/A85) is not a substantial increase over the A75 (3.2MP) whereas 5MP (A95) is.

While I can't really recommend it yet (as I haven't tried one) I think that I would look at the A95 for a few dollars more.

The A95 seems to have taken the best features of the A series and combined them with a 5 MegaPixel imager, and improved 1.8" articulating LCD, to come up with the (almost) perfect "jacket pocket" camera. Add a 12X Image Stabilized Zoom (from the FZ3) and you would have the perfect all-in-one.

Canon and Panasonic need to get together on this... ;)