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Old Oct 29, 2005, 10:14 AM   #41
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I'd say most of us have come to look primarily at: the pixel count to CCD size ratio's affect upon noise while increasing resolution. Then keeping in mind the CCD's size affect upon the true focal length size and weight that system will then demand. Chip size and quality costs mimic that of rare jewels. We realize cramming too many pixels in too small an area produces heat resulting in noise that ultimately will have a negative resolution result. We understand the pros and cons ifs an ands of the currently available chips foveon, sony, etc as well as the bayer mask variant R G B Cy, or at least to some extent we understand. I loved my Sylvania tube system. I love my Yamaha system. I sure as heck would not trade my FZ for any 35mm on the planet if that was all I'd ever have. I never tire of learning and hopefully benefitting from the time spent therein. So far I don't feel like I've been hoodwinked on my purchase. My personal decision was based upon results, the photos various cameras produce.

My interest in following your posts are from a stand pont of file compression. The smallest file that results in the accurate rendering of the picture.

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Old Oct 29, 2005, 12:02 PM   #42
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not upset at all, Ruben... just that a discussion of this nature isn't where i'm at. i was an electronics tech myself for 9 years back in the 70's and 80's, so i know a bit about the subject. and i do appreciate your intention of dispelling any misconceptions about the way these cameras work. it's simply that i don't really care about the deepest mysteries of sensor design. what i DO care about is results, the images a given model of camera can produce, and how those images look when printed in the sizes i use most (5x7, 8x10, and 11x14).

i know, for example,that as you pointed out, basic audio amp design hasn't seen a major improvement in decades, simply because it has already reached the point where any further improvement would be undetectable, and people (aside from the very wealthy or those who are utterly obsessed with perfection at any cost) don't want to pay for "improvements" that don't offer them any discernable benefit. by the same token, i know that more pixels, up to a point, can be a good thing in a digital camera, especially in making larger prints, but beyond that threshold of perception, adding more is superfluous and only serves as a sales pitch talking point. what counts, once that threshold is reached, is not more pixels, but better optics, better sensor designs that yield less noise, and improved camera functions.

i'm perfectly happy with my FZ20, and see no need to by a '30 just because it offers 8MP instead of 5. but if Panny had included some other improvements, like a focus range indicator, an EVF that doesn't freeze up when the shutter is pressed, and a really low-noise sensor, i'd be in line for one right now. i do believe they would have been much better off to roll the '30 out as a 6MP camera... a smaller improvement in pixel count, but on the sensor they're using, that would've resulted in a good deal less pixel (photodiode) density, which in turn would have produced much better noise performance and a better quality image. unfortunately, they chose the "marketing hype" path of jacking up the pixel count as far as it would go on that sensor, so they could claim 8MP and attract customers who lack the basic understanding of the relationship between pixel density, noise, and image quality.

nice Foveon pic. here's one taken with my FZ20 and its Bayer filter sensor. (click in lower right corner to view best image)...


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Old Oct 29, 2005, 1:21 PM   #43
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What type interpolation method did you use to blow up the 2mp? I appears that the 2mp wasn't sharpenned properly. I took the 2mp and was able to sharpen just enough to resemble the 4mp, but because I don't have the originals i don't it will be a fair comparison.

Note to all: One of the points in this experiment is to see whether or not the camera is using some form of interpolation. It may be possible that the camera's hardware is doing some sort of interpolation and possibly sharpening (hardening) of its own. So in the main part of the experiment I seek to know: Can a 2mp image be inflated (using bicubic sampling) and then sharpened at its best (using "Unharp Mask" filter in Photoshop to tweak the sharpness) to very closely resemble the 4mp, look practically the same as the definition of a 4mp. But now this experiment will need to change to some extent based on Ted's new article of "Bayer pattern CFA".
The upsample was done with standard bicubic.

Sharpening does not add detail. If you can't read the lettering on the can unsharpened, you are unlikely to be able to read it after sharpening. Sharpening adds artifacts to give the impression of sharpness when viewed at a distance.

If you compare apples to apples and apply the same processing to both images the 4Mp image still has more detail. I did a quick and dirty sharpening in Sharp Control and a shotgun noise reduction on both images.

2Mp sharpened:

4Mp sharpened:

I dont think this camera really puts out 4 megapixels, detail wise. It appears to be resampling and interpolating from a smaller resolution to higher one, because frankly, I dont see any more detail in "Picture Size = 2304x1728" (4MP) then i do in the smaller resolution of "Picture Size = 1600x1200" ( 2 MP) of my fz15. Not to mention that the small pattern of jagged lines appearing on very picture i take in 2304x1728 mode are a sure sine of poorly done interpolation the camera's internal circuitry, if it is indeed upconverting the resolution. Im not really saying or claiming that is has a 2MP CCD. Im sure that it has a 4MP, but when it is possible to get a 1600x1200 to have the same level of detail and less noise then the higher 2304x1728 mode, then something is wrong no matter how you put. Simply put, It should not be in anyway possible to make a 2 megapixel picture look as good as a 4 megapixel picture, unless of course the 4 megapixel picture started out as a 2 megapixel picture all along. Even then, it will still lack the detail of a "true" 4 megapixel picture.
You seem to think Panasonic is doing a Fuji type smoke and mirrors interpolation of a 2Mp sensor and calling it a 4Mp camera. It is clear to me that isn't the case.

I think the efficiency of sensor interpolations, shapes etc is a red herring on that subject. The sensor captures 4Mp and that is your best resolution. Some of the cameras that use an interpolated resolution to boost their advertised Mp would work pretty much the way you are assuming. But Panasonic isn't doing that.

There is sharpening and such in the processing. Panasonic is good at letting you turn off the noise reduction in some of their models – I wish everyone did that. But assuming the same quality and settings, the processing should be pretty much the same for a 4Mp and 2Mp image.

My guess is that your printing problem with 4Mp images is somehow related to how you are sizing for printing. I would have to follow your workflow to know what is happening. But I can guarantee that you will get a nicer 11 X 14 from a 4Mp image than you will from 2Mp. You get about 157PPI from a 4Mp image and about 109 PPI from a 2Mp. It doesn't matter how much you interpolate or sharpen the 2Mp image – it still has only 109 PPI of detail in an 11 X 14 print. And 109 PPI doesn't give a very good print.

If your use is to display or e-mail images at 800 X 600 or print only in snapshot size, you would probably do fine shooting at 2Mp. I don't get lower noise at 2Mp and that corresponds with the theory. The camera is just downsampling the 4Mp image and the noise is already there. Something is happening in your post processing and I don't really have a handle on what it is.

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Old Oct 29, 2005, 10:46 PM   #44
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The squirl is back!

The squirl is back!

The squirl is back!

good to see you:-)

Hi squirl033and Hito all,

Sorry for the short reply but I have to take my wife somewhere. Glad to see you...

My new experiment coming soon: The new experimentshould be far better, but to avoid confusion i will put it in a seperate post and add the link here when it is ready. It will likely take a few days, maybe 3 to 5to complete. It will be used to measure physical definiton instead of resolution. It will allow people with any brand of camera and almost any cheap photo printer to gauge their own results and compare them with others, and it will be based on simple physical properties that can be reasonably weighed. I cannot guarantee if this is at all possible with my resources, but i can assure you i willdo my unemotional best.

slipe...the 4mp picture cannot be touched, edited,or for that matter, sharpened to make the required comparative results. Furthermore, the 2mp is improperly and insifficiently sharpenned. After two of yourincorrect attemps at the experiment in question, I can't help butwonder if you are protecting your feellings about your camera-- I do hope thatI'm wrong about this. Let me assure you that this is no place for emotional orreligious camaraaffairs. Again, I do hope I'm that wrong about this.If you want to be the one to bring me down, then by all means, but please demontrate proper skills in experimentation and in using Photoshop. I am getting bettercomparitive results withthepicturesyou originally supplied (excluding the last ones because you edited the 4mp) by simply sharpening the 2mp [[only]]. When i come back i will post them so you can see for yourself, but i wont do anything to the 4mp. I found that by roughly using a "threshold of 3 and radius of 1.5 and then tweaking the percentage" in the "unharp mask sharpening filter" in photoshop you can correctly attain satisfactory results to make the comparison against the unedited 4mp. To carry out a proper attitude in this experiment, you cannot allow anyof this to upset you or the results will be biased and useless. If indeed you are upset by what I justsaid, then you have missed the whole point in this on going process.

To those in deep opposition to my experiment: I think Panasonic is outperforming their rivals within their given pricelimitations and market restrictions, and I do think they care about making their best effort to improve their products.Furthermore, Panansonic has to follow the rules of the market to compete andcannot be held responsible for what the market decides is best for you and I to be told. I started this post byillustrating a curiousobervation/experiment about the performance ofmy fz15. But make no mistake, this is not a personal vendetta against this wonderfull company. There is absolutely no reason why anyone should get angry over this. It's just one man's simple experimentwith his fz15, big deal, get over it. I cannot stress enough how important it is to understand that this is nothing more then a simple observation/experiment.

My current observations: This experiment is apparently flawed because there is no way to physically gauge the observations. Sowhile it is worthy of observation,no conclusions can ever be derived from it. It did however help clarify a few things about the so called "Megapixels", and Ihope it will help to enlighten a few.Unfortunetly,theres is a good chance that asmall number of people will likely just breezethrough the post and willprobably miss the point all together, as I have personally witnessed a few times here.

see you guys later and take care:|


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