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Old Aug 6, 2003, 11:22 AM   #1
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Default Recorded Pixels? Effective Pixels? Is the F700 really 6.2 ?

Did anybody ever get a good explanation as to where the F700 is 6.2 pixels or a 3.1 pixel in disguise? The Fugi website shows two pixels side by side in the video about the camera's pixels(one for low light;one for bright light) . It appeared to me that there are 6.2 pixels.

I looked at Canon and Olympus 5 pixel compact cmeras and bought the Fugi. It can be returned and I am trying to figure out if I just bought a real 6.2 pixel camera.

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Old Aug 6, 2003, 1:35 PM   #2
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Quote:
Fujifilm Super CCD SR with 3.1 million S-Pixels and 3.1 million R-Pixels
(6.2 million photodiodes), delivering 6.03 million recorded pixels
*In accordance with CIPA regulations on pixel count
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Old Aug 6, 2003, 2:28 PM   #3
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Just devils advocate here, but does that mean you get 3Mpix resolution for the low and highlights and 6Mpix at mid range! (I would agree the above definition still stands)

I mean, if you've got a night pic shot, you might well have used a 3Mpix camera then, if the highlight pixels are at cutoff?? Could be a case of more width, less depth.

Of course, the saved file output will still represent 6Mpix, but most of the highlight pixel data will be 00hex. How does the low light noise performance compare - like a 6Mpix camera, or a 3Mpix.
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Old Aug 6, 2003, 3:38 PM   #4
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this has been a subject of debate ever since fuji came out with their CCD array. there is a method of interpolation used to create the effective output. they have managed to blur what is a pixel since both types are needed in unison to produce the image.
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Old Aug 11, 2003, 6:25 PM   #5
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If you go by the standards, then it's a 3.1MP, but it interpolates to 6.x pixel "sized" photos.

I believe a while back I saw an article or a post about the Fuji 4900, that said in essence that Fuji had to take the 4.3MP off the box since it was really a 2.4MP that they interpolated up to 4.3MP image size.

You'll notice if you read the boxes of these Super CCD cameras, that Fuji refrains from printing the MP, but instead uses the photo size as their marker for the MP size.
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Old Aug 12, 2003, 6:08 AM   #6
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It's all a question of how you look at it. Yes there aren't 6M discrete photo site pixels on the ccd. Neither is 6Mpix produced by simply scaling up to 6Mpix. Rather it's the other way round. The camera's 'native' resolution is 6Mpix but the trickery is done on the pixel data coming off the sensor (turned through 45 deg.) That's why you'll never find a RAW or TIFF at 3Mpix, which is a downsample. You'll also notice that the levels of in-cam sharpening are different. So when comparing 3Mpix with 6Mpix, it's the sharpening rather than resolution which is making a difference.

What you lose over a standard ccd layout is equal resolution in the normall vertical and horizontal planes - instead you get it at 45 degres. They argue pics 'look better' by a resolution factor of about root 2.

Just apply the root 2 factor (not 2X) when comparing other cams features performance and prices!
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Old Aug 24, 2003, 7:50 PM   #7
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This is exactly the question that has been bothering me for the last several months and I am desperately waiting for a proper review, where someone who knows what they're doing does photos of grids etc.. and lets us know the real issue, how good do the pics look. In the meantime, I have a couple of things to add. First, the are clearly 6million sensors on the chip (3mill low sens and 3mill high sens). But, this does not mean there are 6 million true digital pixels. In fact I think there can't be 6 million, at least not all the time. Clearly when the high sensitivity pixels are saturated (ie: during bright light) then they won't provide any useful information. So, if each sensor is represented, then you would have a photo that had 3 million pixels with image related info interpolated with 3 million white spots (ie: all the saturated pixels). Presumably the camera simply reduces to 3 million pixels under such cicumstances. But this means that during bright light photos, or presumably flash, it can only be a 3 M camera. The opposite must be the case during low light conditions (ie: the low sensitivity pixels would all be black). There might be a small window of light levels where all 6 M pixels could be used but this wouldn't be too great or the wouldn't really be a point in having different pixel types (if they're sensitivity range completely overlapped). So, personally, I think on principle alone, the camera is going to be for the most part a 3M camera. However, it should produce better pictures than a normal 3M camera because it will have a greater dynamic range (ie: it can use hi sens pixels in shadowy areas and low sens pics in bright areas, thus giving a full range of detail across different light levels). However, the resolution (and hence graininess) will still be of a 3M camera. That's my opinion anyway. Finally, since I have been unable to get a review, I went to the camera shop to see if they would let me take some photos and print them out to do side by side comparisons. I directly compared the true 5M canon powershot S50 with the fuji f700. I will preface this with the idea that I went into it hoping the fuji would look better, because I like a lot of it's other features better (including faster and higher resolution video; a much larger iso setting range-canon only goes upto iso 400 fuji goes upto 1600, albeit only at 1M; and it is smaller and lighter). So, I really wanted it to look better so I could finally decide and buy the damn thing. I would further preface this with the comment that just walking into the shops I didn't really know how to work either camera so it is possible that I did something wrong, although I did have the camera guys help. With all that in mind, I have to say, that the canon produced better pictures. There were some nice points to the fuji, the colors were brighter or more saturated and so the overall picture looked brighter at first. But, if you looked closely, the colors were literally saturated, so you couldn't see the texture on a pink dress, it was just a block of pink. Whereas the canon, the pink dress looked more faded but you could see all the folds. Similarly black hair looked richer black on the fuji but you couldn't see as many individual hairs or texture of hair as well as you could see with the canon. And, all thought they were both pretty damn good on the resolution front, in my opinion when we blew up a picture to about 12X18 the fuji looked somewhat more digital. It wasn't quite that you could see pixels, it just didn't look quite real. wheras the canon looked more like film to my eye. Most of these differences probably wouldn't be noticeable if the pictures weren't side by side. In fact, they both did a pretty nice job. But the fuji was clearly losing information (strangley in an area I would have thought it woulld do better in). One thing I did like better about the fuji (in addition to the things mentioned above) was that it seemed to have less of a lag time from pressing the button and when the actual photo was taken. This was not rigorously tested (I just squeezded them both together and it seemed to me the fuji snapped significantly faster than the canon). This seemed cool to me because it seems really annoying how long a lot of the point and shoot digitals take. You go smile, they smile you snap, they stop smiling, then the picture is taken. So, I ended up frustrated. I like some of the techincal features of the fuji better but the canon seemed to take better photos. But, before I go out to get the canon, I am going to wait for a professional review of the fuji, maybe I just didn't have the time and experience to make it perform optimally. So, if anyone finds a good rigorous review out there, please let me know.
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Old Aug 25, 2003, 7:10 AM   #8
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Lordrossi.............It's becoming more and more difficult to compare technical specifications and make a decision based on these objective measures. This is just what manufacturers want. If you're at the cutting edge of sensor design versus cost, you'll do everything you can to market the 'intangibles'.

Start with JPEG. If this is your capture format, then you don't know precisely how much compression has been applied or its algorithm. That Pic you took in the shop may not have been demanding enough to show whether one cam was better than another. You mentioned colorimetry and saturation. Manufacturers will use these things to give a brand 'look' to their products - based on research that probably says most people like high contrast bright pics (even though that may not be you and me).They may also be 'hiding' sensor noise. So if you are comparing like with like, uncompressed TIFFs, BMP's and RAW at least put the file formats on an equal footing.

Then we have in-camera processing - a variable feast and as I mentioned, sharpening is necesary and will be optimised for a particular mass look and appeal. If you're short on Mpix, then software sharpening is cheap. If a 6X4 print can be enhanced to look 'similar' to a cam with a more expensive sensor - how many will notice? - a good picture is a good picture.

But then what makes a good picture? how definable is it in technical spec terms? With so many different impairments produced in different amounts for different pics you can only aggregate them through actual subjective tests and this is extremely difficult. Something like this is done for digital TV, but the result is only a descriptive 5 level scale. That's the best you can do. In the meantime we concentrate on the thing we think makes all the difference - Mpixels, when we should be looking, more critically at the total quality for the widest range of shots. When the first 1Mpix cams came out we latched on to Mpix as the yardstick.

Now there is a plateau in sensor res. for most average shooters so what more are you looking for from future digicam quality - and will you 'see it' first before you can measure it? Fuji are hoping you will see it, rather than ask too many difficult technical questions for re-assurance!

Then there's the lens, not much is often said about this, but it's an expensive component. At what point does the lens fail to deliver on resolution geometry etc or when the Mpix runs out? Sure you can test the complete system for resolution, but which is the limiting factor?

So along come Fuji with a different approach to sensors. Remember, as soon as you design something that works better in some situations than others and is driven by cost optimisation, comparison becomes much more difficult as each manufacturer will have their own reference criteria. Fuji's sensor design means that conventional resolution tests in vertical and horizontal planes aren't quite compatible anymore. But then we are told that resolution presented diagonally is what subjectively matters!

If you leave it to a manufacturer to choose their own test pics, they will always be the best, because they know where the warts are! Although Fuji sometimes seem to choose the poorer pics to post.

What this is all saying is it is becoming more and more difficult to buy picture quality by relying on specs. Whenever you have compression and fancy sensors, you must capture scenes you intend to shoot regularly and if your output is print, print the largest size you may need. Even there, the print process isn't always standardised.

What you should be looking for is a digicam which can handle the widest possible range of picture scenes, at least as good as film and consistently produce acceptable prints of a given size with fewer electronic artefacts than the equivalent film cam. Let me know when you find one and how you've ranked in impairment terms, say film grain against JPEG artefacts or resolution enhancement ! VOX
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