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Old Jun 28, 2005, 10:24 AM   #11
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Old Jun 28, 2005, 10:59 AM   #12
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I know that all other things are not equal here, but the brigher lens on the G6 should give it an advantage over the Pro 1 all along the zoom range.
The G6 will make the same shot at ISO 50 that the Pro1 makes at ISO 100 if you use maximum aperture and keep the shutter the same. So in limited available light where you are shutter speed limited you can take the same shot with a lower ISO setting. That should give you less noise. But once you get enough light that both can use their lowest ISO I don't think the fact that the G6 would be using a faster shutter or have its lens stopped down an f-stop would affect the noise. That is probably what you already said but relativity is one of my weak points.

Reviewers seldom do sample photos under conditions where the G6 would have an advantage in that regard.


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Old Jun 28, 2005, 12:22 PM   #13
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Old Jun 28, 2005, 1:09 PM   #14
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I think the dark and light sensors apply only to some Fuji CCDs that have sensors less light sensitive to extend the dynamic range mixed with more normal higher sensitivity ones.

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Whatever the noise problem is, it does appear that the number of sardines packed into the sensor is only part of the problem.
[/quote]

This is a really interesting post: http://www.nikonians.org/cgi-bin/dcf...p;viewmode=all

It corresponds to some things I have been thinking about lately. My tests with shooting with the flash out of range seemed to agree with the post. Every shot ended up with the same noise after I adjusted to the same light level. They were taken at different ISO. Even the ISO400 shot dovetailed perfectly once I sharpened it back up.

I have also noticed that if I pull shadow detail from a shot taken at low ISO the shadows I pull up are noisy. As noisy as they would have been had I taken the shot at higher ISO to get the shadows.

I don't know what that has to do with density or why a DSLR gives lower noise. From my limited reading on the subject I had thought it was a result of cross fertilization or cross talk between adjacent sensors. Stray electrons are picked up from adjacent sensors as I understand it in the conversion stage. But for a given sensor, less light produces more noise as the above post points out.

There is also thermal noise. I think that is mostly what the long exposure noise reduction removes. But it does evidently appear in normal shots.


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Old Jun 28, 2005, 9:03 PM   #15
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Just a few words about sensor size, focal length and f-stop.

Typically a "normal" perspective (closest to what the eye sees) is achieved with a focal length approximately equal to the diagonal size of the film or sensor. That is why normal for 35mm is about 44mm (most lenses were actually 50 or 55mm, close enough). A 7.2mm sensor needs only a 7.2mm lens to get the same perspective.

Now how does this relate to aperture? The f-stop of a lens is actually the focal length divided by the effective aperture size therefore a 50mm lens with a 25mm aperture would be an f2 lens. 25mm is a substantial size, the 7.2mm lens would only need a 3.6mm aperture in order to be an f2 lens. Obviously this means a much smaller opening and therefore a physically much smaller lens.

As for the minimum f-stop, most of these small lenses do not stop down more than f8 because by then the physical aperture is so small that diffraction would degrade the image (f8 on a 7.2mm lens would yield a physical aperture of only 0.9mm, f16 on a 50mm lens is still 3.125mm, much larger, no fear of diffraction here). I often see people complain about the limited f-stop range but remember that 200mm lenses often go to f22 or even f32, medium format lenses often have an f45 setting and large format went to f64 (thus the photography group of the same name). Apertures smaller than f11 on a small sensor camera would produce very poor results since you now have a pinhole camera with a very small pinhole, and a lens in the way.

Pixel density does have theoretical limits however we have not reached them yetand advances in sensor design allow us to increase density with little loss of quality (the initial 8MP prosumers not withstanding). For most of us a camera in the 6 to 8 MP range offers all of the resolution we would normally need but as advances continue we may see still higher numbers in small sensor cameras. Larger sensors in smaller cameras will probably appear but remember that sensor size has an immediate impact on lens size and, like Slipe, I like the smaller camera size and the wider zoom ranges possible.

It took two lenses in my 35mm SLR kits to equal the modest 6X zoom of my Fuji S7000, a new Canon S2 IS doubles that range and is physically even smaller (smaller sensor). Add to this the flexibility of ISO and White Balance on digital cameras and you would need at least two 35mm bodies loaded with different films. My usual 35mm kit was 2 bodies, 4 lenses, two flash units and numerous filters. Now I carry the camera, one flash unit and a couple of Cokin filters in a small bag which weighs only about a quarter of my 35mm outfit. And the "noise" produced by the S7000 is still far less intrusive than most of the 400 speed film I ever used. And the 12MP mode may be interpolated but it still produces excellent 11" X 17" prints.

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Old Jun 28, 2005, 9:44 PM   #16
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Monza76 wrote:
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It took two lenses in my 35mm SLR kits to equal the modest 6X zoom of my Fuji S7000, a new Canon S2 IS doubles that range and is physically even smaller (smaller sensor). Add to this the flexibility of ISO and White Balance on digital cameras and you would need at least two 35mm bodies loaded with different films. My usual 35mm kit was 2 bodies, 4 lenses, two flash units and numerous filters. Now I carry the camera, one flash unit and a couple of Cokin filters in a small bag which weighs only about a quarter of my 35mm outfit. And the "noise" produced by the S7000 is still far less intrusive than most of the 400 speed film I ever used. And the 12MP mode may be interpolated but it still produces excellent 11" X 17" prints.

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i agree. i have a Panasonic FZ20, uses a 10mm sensor for 5MP. the 12x zoom lens on this beast will do more all by itself than an entire bagful of optics did when i used a Pentax ME Super, and the images i get with the FZ20 are at least as good, if not better in terms of clarity and color rendition. it's "only" 5MP, but it makes 8x10 prints, or even 11x14 without interpolation, that are indistinguishable from goodfilm photos. and if there's any noise, as there sometimes is in low-light settings, it's far easier to remove than the grain from using 400 speed film. i oncetried some telephoto shots in a sports arena with 1600 ASA film (which i had to use to get my f5.6zoom lens to yield a half acceptable shutter speed) that came out looking like pointilist art! i could take that same shot now with my FZ20, at f2.8, and the noisewould befar less objectionable (in addition to having twice the zoom range), and, as i mentioned, it can be easily removed using any one of half a dozen readily available post-processing programs. try THAT with film grain!

is the MP race worthwhile? nah, not to me. it's just a marketing tool, sorta like "total harmonic distortion" was with stereo amps back in the '70's. all the amp makers were bragging about "less than .005% THD" or some such thing, when the human ear can't detect distortion below .03%! same with pixels. unless you're planning on a lot of 20x30 poster prints, there's not much reason to bother with 7 or 8 or 10 MP. 4 or 5 will do just fine for the shots most people take, even enlarging to 8x10 or more, and will produce less noise. i havea closeupshot of a blue-and-gold macaw that i took as a test, to see how it would print at 11x14. it has lots of veryfine detail, dark areas where noise would show if there were any, and sharp edges that would reveal any "jaggies" that might arise from over-enlarging to the point that pixelation became visible. that picture printed flawlessly at 11x14 with no interpolation. 5MP is plenty. the higher pixel counts are just something for the salesman to point to as justification for a higher price. i suppose there are times when only more pixels will do, like if you want to blow up a shot to 20x30 or bigger, but how many hobbyists do that on any regular basis?i know in my house, by the time i get an 11x14 matted and framed, it takes up enough room on my wall that a 20x30 would be out of the question!


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Old Jun 28, 2005, 10:24 PM   #17
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is the MP race worthwhile? nah, not to me. it's just a marketing tool
Where do you want to cut it off? People were saying that back in the 2 and 3Mp days. Would you be happy with a 2 or 3Mp camera? I wouldn't. If they could make a 10Mp 1/2.5 sensor with decent noise so you could get a 12X stabilized zoom that would maintain f2.8 I would be very happy to buy it. Hopefully somebody besides Panasonic would make it so it could have some physical controls and you could see the viewfinder with a flash unit attached.

I recently upgraded my pocket camera to a 7Mp. I did it mostly for size, LCD and controls. But my 13 X 19 prints are better than they were with 5Mp. I can still generate only around 160 PPI with the 7Mp – more would be better. I think the big prints look a lot better on the wall. The largest 11 X 14 crop you can get from your 5Mp is around 175 PPI if you don't do any cropping. They would look nicer with more pixels.

A few years from now 5 and 7Mp will be pitifully small. And people will be very happy with their new 16Mp low noise cameras and feel the world should stop there – just like they did when they got their 2Mp UZI or 5Mp FZ. I think they are doing very well with the MP race. Each series of cameras has better resolution and they are keeping the noise better than the detractors had predicted.

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Old Jun 29, 2005, 12:31 AM   #18
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squirl033 wrote:
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i suppose there are times when only more pixels will do, like if you want to blow up a shot to 20x30 or bigger, but how many hobbyists do that on any regular basis?*i know in my house, by the time i get an 11x14 matted and framed, it takes up enough room on my wall that a 20x30 would be out of the question!
Don't forget cropping as a reason for more megapixels. And at some resolution point "digital zoom" is no longer a dirty word, at least on point and shoot cameras.
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Old Jun 29, 2005, 7:07 AM   #19
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With the higher resolution, why not have a cropped zoom instead of digital? On my 7mp camera I would be more than happy on some shots to make do with the central 2mp and have the camera expose that properly. That would give me around 200mm equivalent instantly but with no digital zoom noise penalty. This would save me cropping in photoshop and correcting the exposure of the cropped image.

BruceMcL wrote:
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squirl033 wrote:
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i suppose there are times when only more pixels will do, like if you want to blow up a shot to 20x30 or bigger, but how many hobbyists do that on any regular basis?i know in my house, by the time i get an 11x14 matted and framed, it takes up enough room on my wall that a 20x30 would be out of the question!
Don't forget cropping as a reason for more megapixels. And at some resolution point "digital zoom" is no longer a dirty word, at least on point and shoot cameras.
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Old Jun 29, 2005, 11:08 AM   #20
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I am really enjoying and learning from this thread. Thanks for contributing everyone.

slipe wrote:
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If there is noise reduction converting from raw to JPG it blurs the image.* Even sophisticated noise reduction programs blur the image a little.* But the trade-off is acceptable to me if the settings are kept subtle and you use a plug-in so you can avoid edges and treat areas like sky differently.* The trade-off isn't acceptable to me for in-camera noise reduction and I wish I could turn it off on cameras that use it.* I prefer full sharpness with the noise and I can take it out myself if it is too obnoxious.*
Cameras are becoming more and more programmable these days. Manufacturers are allowing users to change what is on top level menus, create their own "modes" or combinations of settings, and in some cases assign created modes to physical knobs or buttons.

Someday it would be great if a camera manufacturer allowed people to write their own firmware. That would solve slipe's delimna mentioned above. He could look around on the "Photozilla" or sourceforge web sites for an alternative build of his firmware that allowed adjusting the noise reduction.

I would say that Mozilla is the main reason that web browsers are getting better. It took a while for the project to get to this leadership position. Netscape, the company that deliberately turned their browser into an open source project, doesn't exist as a company any more, it's just a brand of AOL. So there are definitely risks involved in a manufacturer doing this. I would like to see it happen though. I think there are some major potential benefits to photographers.
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