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Old Aug 19, 2002, 11:49 AM   #1
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Default Slow writing/reading Fuji S 602

I want to use the 602 at the best quality i.e 6Mp and H because I want the highest quality prints. Unfortunately, with a IGb. Microdrive, the camera locks for minutes, before finishing writing. Then it takes about 30 seconds to change viewing from one pic to the next. Does anyone else think this is unsatisfactory?

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Old Aug 19, 2002, 1:01 PM   #2
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This is normal and would do the same even with flash on any consumer camera! The speed is limited by the camera design with cost being more important than transfer speed (ie both the 1G microdrive and the flash cards are way faster than your camera can handle!). Shoot in jpeg and you'll be fine...

http://www.stevesforums.com/forum/vi...d.php?tid=1952

http://www.stevesforums.com/forum/vi...d.php?tid=2019

[Edited on 8-19-2002 by NHL]
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Old Oct 6, 2002, 5:28 PM   #3
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I've tried the tiff mode and 6m J.Peg. you cant tell the difference in quality.Try it in comparison I bet you cant tell the apart, and it works fast enough for me!
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Old Oct 7, 2002, 5:45 AM   #4
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See my previous post and you have the answer: 3.1Mpix fine mode!

Why waste time and batteries with more in-cam processing for same or worse result?

http://www.stevesforums.com/forum/vi...d.php?tid=3135

[Edited on 10-7-2002 by voxmagna]
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Old Oct 7, 2002, 10:50 PM   #5
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Default Tiff mode

Your taking pictures in Tiff mode which means the pictures are about 17 megs for each picture. You cant expect it to be fast when dealing with 17 meg pictures. Take them in JPG format.
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Old Oct 26, 2002, 7:46 PM   #6
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Howdy,

I own the S602Z as well. When I'm not shooting my digital camera, in my spare time I'm a professional software engineer so I know a thing or two about how images are stored.

The only difference between 6MP High and 6MP Fine is, effectively, the image format. Let me explain...

TIFF is what's called a "lossless" image format. For each and every bit of information collected by the CCD, there is a pixel represented in the image (well, not actually, because this particular camera has a super CCD, which I'll talk about in a minute). The JPEG image format is a "lossy" format, meaning that some information in the image is lost. However, in the JPEG format the user has control over how much information is lost.

Primarily, when converting lossless images to JPEG, the information lost is color information. The camera's CCD can differentiate between far more colors than the human eye effectively can. I say "effectively" because, while the color range of the human eye is astonishing, the eye is not simply a lens--we have a brain behind it that plays all kinds of tricks on our vision and fills in information that isn't actually there. So, if your eye sees a color gradient in low light, say from a saturated blue to cyan, you're going to think that it's not as much of a spread between the two extremes as if you see that same gradient in high light. The point is, JPEG is designed to do away with gradients that you can't see for the purpose of compressing the image size. When you shoot on 6MP Fine, the difference is so slight to the human eye that you shouldn't be able to tell the difference between that and a 6MP High shot.

To get an idea, take the exact same image with all the same settings and conditions in both modes, and then put the image in photoshop (make sure your monitor is adjusted correctly). Crop out a finely detailed area of both shots and blow them up side by side until you see a difference. Keep track of how much you cropped and multiply the inverse by any zooming you do. So, say you cropped out 10% of the original image--make sure you keep the same proportions or you'll throw off the calculations--and then zoomed in by 920% before you saw a difference:

inverse of crop: 1/10% = 1/0.10 = 10

Then, the zoom: 920% = 9.20

Multiply them: 9.20 * 10 = 92 = 9200%

Using these numbers, that means you blew the image up by almost 100 times before you saw any difference. 100 times the area is, keeping the original proportions of the image, 10 times in each dimension. A 6MP High image at 72 pixels/inch resolution equates to a 40" x 30" image.

What's all this mean? It means that if you took two pictures, one at 6MP High and the same one at 6MP Fine, and blew them up 10 times in each dimension to 400" x 300" (33'4" x 25'), you'd just begin to see a difference in quality between the two images. Of course, all these calculations assume that the original 10% cropping and zoom of 920% hold, but you get the idea so you can work the numbers for yourself based on your own judgment of the side-by-side comparison of image quality.

Now, to get back to the super CCD issue, this is another highly mitigating factor. The reason is, the image resolution provided by 6MP High is actually an *interpolated* image. That's right. This is because the super CCD uses hexagonal photocells to collect light, as opposed to the traditional rectangular array. This allows a much better image, and to prove it to yourself think through the following thought experiment with me.

Imagine an image which is half black, half white, with the edge vertically oriented in the image. The edge is perfectly vertical. If you zoom in on that image in photoshop, no matter how much you crop and zoom you're always going to see a perfect line of black on one side, and white on the other. Now, imagine the same picture but the edge is not perfectly vertical--it's jumps over one pixel to the right as you go toward the bottom. With a regular rectangular array of photocells, the horizontal jump over is going to be the distance between the centers of two photocells. If you think about the way hexagons tile a surface, though, you'll see that the horizontal jump is going to be *half* the distance to the next photocell horinzontally over. This means that there will be one step over in the black/white edge with a rectangular array, but two with the super CCD. This means you get, absolutely, a 133% higher resolution image with the same number of photocells with the super CCD, and effectively a 150% increase in resolution.

If you zoom enough in photoshop, what you'll eventually find at the exact edge of the black/white boundary is that there were some photocells that collected some white and some black, meaning they're grey. Now think about what JPEG does, it takes all those millions of shades of grey in the original bitmap image and only represents the shades that can be determined by the human eye (at the highest quality JPEG--it samples even lower numbers of shades at lower qualities). In other words, you can't really tell the difference at any reasonably sized blow-up.

So, based on this argument, my advice is to shoot images less than 1/7th the size on 6MP Fine and don't waste your time and memory on 6MP High. And if you're only shooting for 5" x 7" prints, then I would choose between 1MP Fine and 3MP Normal--3MP Fine if you're worried about the images or if you think you might go 8" x 10".

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Old Oct 28, 2002, 6:25 AM   #7
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Does anybody know how lens quality limits the theoretical resolution explanation which sev has provided? Should we assume that the lens contributes nothing, or is insignificant? Nobody will challenge a manufacturer who claims XMpix, 'cos that's what the ccd, software and chips produce.

Surely, what really matters is will the cam/ccd/software combination achieve some measure of output picture sharpness in relation to shooting a real image with detail, tested in a way which as far as possible, is output device (monitor/printer) independent.
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Old Oct 28, 2002, 3:28 PM   #8
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This is a very difficult question to answer, because lens quality and resolution are orthogonal concepts. What does that mean?

It means, take a macro closeup of a flower at a wide-open f-stop. Make sure the background is completely blurred into abstract blotches. Now, take a look at the items in the background. What is their "effective" resolution? Well, if you took the shot at 6MP, then the resolution is 6MP everywhere in the image, even though they're so blurred you can't tell what they are.

Lens quality is important, but it is a totally independent idea from resolution. The reason it's important--imagine that you are taking a picture of exquisite scrollwork on a plane that is exactly perpendicular to your shooting angle, so the entire thing should fall into the same focal plane and be exactly in focus.

If there are spherical aberrations in the lens, or dust, scratches, chips, any defect imaginable, then each ray of light entering that lens will not end up focused on the CCD sharply. With a poor quality lens, you'll still be able to take hi-res pictures, but the lens will inject artifacts into the image. An artifact is a color or shade variation that appears in the image that was not originally there. A spherical aberration will turn a straight line into a squiggely one.

Bad lenses can cause color casts on the image as a whole, changing the relationship of one color to another. They can also be sensitive to light waves in the non-visible spectrum (in fact, most are), so you have IR or UV light which the human eye cannot see changing the overall relative qualities of the image.

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Old Oct 28, 2002, 5:10 PM   #9
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I'm not sure I completely understand. The lens and ccd together provide the resolution. Isn't that why cameras are tested by pointing them at resolution test charts, which measure how many 'lines' can be resolved?

I agree that 6Mp equivalent of data might be present in a stored image, but if the resolution measured in lines vertically or horizontally from a test chart, does not equate to the number of pixel samples (Nyquist,modulation Index and all other things considered) - doesn't that mean you're wasting time/storage and money on the digicam to give sharpness of detail it can't deliver?

Isn't it like saying, I've put a very fine grain film in my Brownie box (6Mpix+ worth!). Yes there may be less noise on the image, but I can't see any detail on my prints 'cos the lens is so poor. So I'll go and buy a Nikon put the same film in it and wow do I see a difference!
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Old Oct 29, 2002, 7:15 AM   #10
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The number of photocells in the CCD, their shape, and their arrangement determines the resolution. If you have a lousy lens that can't hold a focal plane, the poorly projected image will still be recorded at whatever resolution the CCD is capable of.

There are many things that affect overall image quality, of which resolution is one. Resolution has a very specific meaning, and only a specific aspect of image quality is being referred to by it. A lens quality issue, such as a spherical aberration, for example, also affects image quality but in a completely different manner. A bad lens can also affect image quality in other ways, such as color casts, reflections, internal dirt or dust, etc. These are all factors, but independent of the idea of resolution.

Think of it this way...the better the resolution, the more accurately the CCD will record any defects present in the lens.

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