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bobo69
08-14-2004, 01:18 PM
Can you go by the interpolated "6megapixles" that they advertise or is that some sort of term for blowing the image up?

thanks

bobo

Rhys
08-14-2004, 01:39 PM
Can you go by the interpolated "6megapixles" that they advertise or is that some sort of term for blowing the image up?

thanks

bobo

interpolated means:

Definition: interpolated resolution
The resolution a device can generate by using a process known as interpolation -- estimating intermediate values based on the knowledge of two known values in a sequence.
(http://www.computeruser.com/resources/dictionary/popup_definition.php?lookup=8369)

In`terīpo`la`ted
a. 1. Inserted in, or added to, the original; introduced; foisted in; changed by the insertion of new or spurious matter.
2. (Math.) Provided with necessary interpolations; as, an interpolated table.
(http://www.thefreedictionary.com/Interpolated)

Basically, it means taking the picture and stuffing guessed bits in to try to make it bigger.

bobo69
08-14-2004, 01:51 PM
Cool, thank you!! (so stay away from it!! )

Rhys
08-14-2004, 02:03 PM
Cool, thank you!! (so stay away from it!! )

Good idea :)

Watch out for digital zoom as well.

If you look for actual megapixels and optical zoom, you won't go far wrong :)

John_Reed
08-14-2004, 04:57 PM
Good idea :)

Watch out for digital zoom as well.

If you look for actual megapixels and optical zoom, you won't go far wrong :)Most digital cameras have a sensor laid out in a "Bayer" matrix, consisting of 50% "green" sites, 25% "red" sites, and 25% "blue" sites. So if you have, say, a 4,000,000 pixel camera, its sensor will really have 2,000,000 "green" sites, 1,000,000 "red" sites, and 1,000,000 "blue" sites. (On the CCD chip, they're really all the same color, but by using filters, manufacturers can make certain sites sensitive only to Green, others to Red, others to Blue) But, when your camera proceeds to create an image file after you've captured a photo, the going starts to get tricky. Each individual pixel of the "4 megapixel" image will need three components of color: A Green byte, a Red byte, and a Blue byte. Since there are 4,000,000 total pixels needed for the entire image, that means that 2,000,000 Green bytes need to be generated, 3,000,000 Red bytes and 3,000,000 Blue bytes also have to be generated. How is that done? It has to be done by interpolation. The only cameras that don't use interpolation for generating images are those that use the 3-layer Foveon technology, where each sensing site contains an R, G, and B layer, stacked so as to be coincident.

judge9847
08-14-2004, 05:40 PM
What a great explanation of interpolation by John - highly technical and complicated stuff made to sound simple! Top marks, Brother ;)

It seems a bit churlish to add more but interpolation is, if I've got it right, one of the main reasons why the traditionalist (film) photographers claim digital imaging isn't "real" photography at all and maybe they've got a point. To a certain degree, the camera isn't really collecting all the information for the final image from the scene in front of it when the shutter release is activated, in the way that a film camera does. It has to use interpolation - or a sophisticated system of guesswork if you want to call it that. Because of that, it could be argued that a lot of the detail is, in effect, "computer generated" and therefore not "real" photography.

Personally speaking, I think that's a lot of round things but I understand the argument.

But don't get carried away with worrying about it. As John says, it's the way most digital cameras work.

What I can't make up my mind about though is the "interpolated 6mp" that you talk about. I think that it means there's a 3mp sensor in the camera which uses interpolation to get an effective 6mp image. But using John's explanation, I now think it could mean that it's a 2mp sensor.

Help!!

Rhys
08-14-2004, 06:24 PM
What a great explanation of interpolation by John - highly technical and complicated stuff made to sound simple! Top marks, Brother ;)

It seems a bit churlish to add more but interpolation is, if I've got it right, one of the main reasons why the traditionalist (film) photographers claim digital imaging isn't "real" photography at all and maybe they've got a point. To a certain degree, the camera isn't really collecting all the information for the final image from the scene in front of it when the shutter release is activated, in the way that a film camera does. It has to use interpolation - or a sophisticated system of guesswork if you want to call it that. Because of that, it could be argued that a lot of the detail is, in effect, "computer generated" and therefore not "real" photography.

Personally speaking, I think that's a lot of round things but I understand the argument.

But don't get carried away with worrying about it. As John says, it's the way most digital cameras work.

What I can't make up my mind about though is the "interpolated 6mp" that you talk about. I think that it means there's a 3mp sensor in the camera which uses interpolation to get an effective 6mp image. But using John's explanation, I now think it could mean that it's a 2mp sensor.

Help!!

The way Bayer images are constructed is largely ignored by the "interpolated 6mp output" claim. What they refer to there is that they take a 3mp Bayer picture and blow it up to 6MP.

John_Reed
08-14-2004, 11:20 PM
What I can't make up my mind about though is the "interpolated 6mp" that you talk about. I think that it means there's a 3mp sensor in the camera which uses interpolation to get an effective 6mp image. But using John's explanation, I now think it could mean that it's a 2mp sensor.Thanks, Bob. But if you're referring to the Fuji S5000, which has a 3MP sensor that generates 6MP images, i'm not sure it can be characterized as a "Bayer Sensor," though I think it's still true that the 3 million sensing sites are divided 1/2, 1/4, and 1/4 for G, R, and B respectively. I think Fuji, whose sensor is laid out in a diagonal array rather than a square grid, is forced to interpolate to 6MP to "square up" the image. But does it work? Here are three resolution comparison charts from dpreview Phil Askey's review of the Canon S1, the first chart for the (3.2MP) S1, the second for the (6MP) S5000, the third for the (4MP) Panasonic FZ10. Judge for yourself which one has the highest resolution?
http://www.dpreview.com/reviews/CanonS1IS/Samples/comparedto/canon_s1is-001.jpghttp://www.dpreview.com/reviews/CanonS1IS/Samples/comparedto/fuji_finepixs5000-002.jpghttp://www.dpreview.com/reviews/CanonS1IS/Samples/comparedto/pansonic_dmcfz10-001.JPG

judge9847
08-15-2004, 04:01 AM
Rhys, thanks for that but you'll have to forgive me being a bit of a thicko! It comes with age I'm afraid :)


What they refer to there is that they take a 3mp Bayer picture and blow it up to 6MP.

I don't understand what you mean by "blowing up" to 6mp: are you referring to the output of what is the final image which is made bigger simply by increasing resolution or are you saying that interpolation is used to get to the 6mp mark? If that's so, then though I might not have been able to explain it quite like that, it's what I thought I was saying.

John, there was quite a lot of noise from Fuji about one of their more recent cameras when the informed press were suggesting, that despite their claims, all Fuji were doing with the imaging was using interpolation to get it to the size that was being claimed. I'm almost sure it was the S7000z which Fuji proudly claimed had a top image size of 4048x3040 but needed 12mp to produce it. If memory serves me correctly, Fuji claim that it is indeed a 12mp sensor but the counter claim is it can only be achieved by electronic wizardry taking the 6.3 effective mp of the sensor up to 12.

I have a Fuji 6800z and that uses the 2nd (?) generation CCD and claims to generate a 6mp - 2832x2128 - image from the 3.3 mp sensor. Fuji call it "image processing" but the rest of the world would, I'm sure, all it interpolation. Mind you, to my untrained and uneducated eye, the output at that resolution is remarkable.

D70FAN
08-15-2004, 07:57 AM
Rhys, thanks for that but you'll have to forgive me being a bit of a thicko! It comes with age I'm afraid :)



I don't understand what you mean by "blowing up" to 6mp: are you referring to the output of what is the final image which is made bigger simply by increasing resolution or are you saying that interpolation is used to get to the 6mp mark? If that's so, then though I might not have been able to explain it quite like that, it's what I thought I was saying.

John, there was quite a lot of noise from Fuji about one of their more recent cameras when the informed press were suggesting, that despite their claims, all Fuji were doing with the imaging was using interpolation to get it to the size that was being claimed. I'm almost sure it was the S7000z which Fuji proudly claimed had a top image size of 4048x3040 but needed 12mp to produce it. If memory serves me correctly, Fuji claim that it is indeed a 12mp sensor but the counter claim is it can only be achieved by electronic wizardry taking the 6.3 effective mp of the sensor up to 12.

I have a Fuji 6800z and that uses the 2nd (?) generation CCD and claims to generate a 6mp - 2832x2128 - image from the 3.3 mp sensor. Fuji call it "image processing" but the rest of the world would, I'm sure, all it interpolation. Mind you, to my untrained and uneducated eye, the output at that resolution is remarkable.

When you look at the 100% crop the 12MP image is only moderately better that 6MP. This is because interpolation takes the base 6MP image and adds pixels in post processing that approximate adjacent pixels. You can do that yourself using any number of software image processors, with better results.

To get an idea of how rediculous the claim is, compare the image from a Canon EOS 1Ds (11.1MP) to that from a Fuji interpolated 6/12MP image. An unfair comparison you say. Pitting a $700 consumer digicam against a $7500 Pro SLR?

No more so than Fuji claiming 12MP imaging performance from a 2/3" 6MP CCD. At the very least misleading. A lot of people were mislead thinking the Fuji images were superior to other 3, 4, and 5MP images. When in fact they are not, and in some cases the oposite is true.

my 5 cents worth (2 cents with many years of inflation, or interpolated if you will).

John_Reed
08-15-2004, 09:08 AM
No more so than Fuji claiming 12MP imaging performance from a 2/3" 6MP CCD. At the very least misleading. A lot of people were mislead thinking the Fuji images were superior to other 3, 4, and 5MP images. When in fact they are not, and in some cases the oposite is true.Case in point is the comparison sequence above, where Askey was shooting the Fuji in "6MP" mode. To me, its resolution looks to be the worst of the three, not even as sharp as the 3.2MP Canon. Jake hasn't weighed in on this issue, though, so maybe he'd have a different take on it. Hey, the Smilies are back! :D Thanks, Jeff!

Jake Conner
08-15-2004, 01:37 PM
That's because the S5000 is a piece of crap, straight up, SCCD or no. Compare the S7000 to another small-sensor 6MP, and you might get a different result.

Jake

esemones
08-26-2004, 06:30 PM
While discussing image clarity, is there a significant observable difference between the size (1/1.8, 1/2.4, etc) of the CCDs and their resultant photos?

esemones
08-26-2004, 06:58 PM
Sorry, link answers in spades: http://www.dcresource.com/forums/showthread.php?t=442&page=1&pp=10

PixChick
08-30-2004, 10:32 PM
The only cameras that don't use interpolation for generating images are those that use the 3-layer Foveon technology, where each sensing site contains an R, G, and B layer, stacked so as to be coincident.

As a point of curiousity--can you tell me which cameras use the 3-layer Foveon technology? Good explanation in that post--thanks!

PixChick :)

Jeff Keller
08-30-2004, 10:44 PM
As a point of curiousity--can you tell me which cameras use the 3-layer Foveon technology? Good explanation in that post--thanks!

PixChick :)

I'm not John, but...

Sigma SD9, SD10 ($$$)
Polaroid x530 (still not shipping)

PixChick
08-30-2004, 11:15 PM
I'm not John, but...

Sigma SD9, SD10 ($$$)
Polaroid x530 (still not shipping)

Thank you.

Sooooooo, do you think that we might start to see more cameras with this technology, that this will eventually become the standard and replace the CCD? Do you think that the Foveon sensor will necessarily always give a better quality image than the CCD? Am I asking for too much speculation?

PixChick :)

D70FAN
08-31-2004, 07:55 AM
Thank you.

Sooooooo, do you think that we might start to see more cameras with this technology, that this will eventually become the standard and replace the CCD? Do you think that the Foveon sensor will necessarily always give a better quality image than the CCD? Am I asking for too much speculation?

PixChick :)

1. Not for the forseable future, and most probably not in consumer all-in-ones.

2. It is very promising technology, but they have had to hitch their horse to the slow wagon. If Canon or Nikon had adopted this technology in one of their pro dSLR's then they would have had a better chance. Not that the Sigma cameras are bad, they just lack the "star" power of the two leaders.

Also the image quality is not necessarily better in all aspects, but the images are very good and compare well to 6MP dSLR's. CCD technlogy is more than holding its own against other technologies, so I would imagine that they will just co-exist in the future.

John_Reed
08-31-2004, 08:43 AM
Also the image quality is not necessarily better in all aspects, but the images are very good and compare well to 6MP dSLR's. CCD technlogy is more than holding its own against other technologies, so I would imagine that they will just co-exist in the future.Well, at low ISOs, anyway. From Jeff's review of the Sigma SD10, here's his shot at ISO 400:
http://www.dcresource.com/reviews/sigma/sd10-review/nightshot400-crop.jpg
It's hard to say whether high-ISO performance is inherently limited with the Foveon sensor, or is limited by the camera's electronics. (I suspect the former; intuitively, it seems to me that, square micron for square micron, the single-color dSLR sensor site will out-perform the triple-color Foveon sensor site, ISO-wise) But in this embodiment, the Foveon is doing no better than pro-sumer CCDs. I'm really curious to see how that new Polaroid X530 will perform in the fixed-lens market. It may be a sleeper.

D70FAN
08-31-2004, 05:12 PM
Well, at low ISOs, anyway. From Jeff's review of the Sigma SD10, here's his shot at ISO 400:
It's hard to say whether high-ISO performance is inherently limited with the Foveon sensor, or is limited by the camera's electronics. (I suspect the former; intuitively, it seems to me that, square micron for square micron, the single-color dSLR sensor site will out-perform the triple-color Foveon sensor site, ISO-wise) But in this embodiment, the Foveon is doing no better than pro-sumer CCDs. I'm really curious to see how that new Polaroid X530 will perform in the fixed-lens market. It may be a sleeper.

I was trying to be kind, but a picture is worth a thousand words.