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jazzisit
10-28-2004, 05:50 PM
I recently purchased the Panasonic Z20 and was very disappointed in the image quality. I did notice in Photoshop, and I believe Steve's Digicam's (or one of the other major camera review sites) EIF information on the gallery pictures that the Z20's resolution is only 72 pixels per inch, even at the highest quality. My Canon G3 is 180 pixels per inch and that's a pretty old camera in tech years. Does anyone know if this is the reason why the pictures are so noisy. Any way to increase it? Thanks in advance!

Turbosloth
10-28-2004, 08:14 PM
I recently purchased the Panasonic Z20 and was very disappointed in the image quality. I did notice in Photoshop, and I believe Steve's Digicam's (or one of the other major camera review sites) EIF information on the gallery pictures that the Z20's resolution is only 72 pixels per inch, even at the highest quality. My Canon G3 is 180 pixels per inch and that's a pretty old camera in tech years. Does anyone know if this is the reason why the pictures are so noisy. Any way to increase it? Thanks in advance!

I was comparing FZ10 and FZ20 images and you're right. The resolution on the FZ20 is only 72 pixels per inch. But I doubt that's the cause of all the noise, they're only 72 pixels on the FZ10 too.

Personally, I think the FZ10 has superior image quality, especially when fully zoomed. Images appear sharper and there is definetally way less noise.
While on the FZ20, every image I have seen which includes sky, has very visible noise, even when viewing the picture in lower resolutions.

Billiam
10-28-2004, 09:14 PM
Pixels per inch has nothing to do with noise. 72 ppi is standard resolution for display on a monitor. If you actually printed a 5 mp (2560 x 1920) image from an FZ20 at 75 ppi, the print would measure 35" x 27". For printing you would want to rescale the image in software. 250 ppi would yield an 8" x 10" print, and that's plenty of resolution.

nooner
10-29-2004, 12:55 AM
The noise is a factor when viewing on monitors but try printing a few photos and see what you think.

RobertJ
10-29-2004, 04:26 AM
I recently purchased the Panasonic Z20 and was very disappointed in the image quality. I did notice in Photoshop, and I believe Steve's Digicam's (or one of the other major camera review sites) EIF information on the gallery pictures that the Z20's resolution is only 72 pixels per inch, even at the highest quality. My Canon G3 is 180 pixels per inch and that's a pretty old camera in tech years. Does anyone know if this is the reason why the pictures are so noisy. Any way to increase it? Thanks in advance!

As Billiam has said, pixels per inch is not even a factor in the actual camera image. A pixel is a pixel - the factor is how many there are in total.
Pixels per inch only comes into the quality when printed - and thats a printer factor, not the camera

jazzisit
10-29-2004, 05:48 AM
Thanks for all your replies. I'm still a little confused. If what RobertJ says is true that the pixels per inch only comes into quality when printed (which I've read as well), does that mean that the "printed" 72 ppi will be of less quality than the 180 ppi of the Canon G3 or the 300 ppi of the higher end cameras. Also, if I increase the ppi for printing at the suggested 300 ppi (as different books suggest for printing pictures), the software just adds misc pixels to make up the difference and that lessens the quality as well? My printed pics are not coming out that impressive as well which is very disappointing for me because this camera has every single thing I've been looking for in a digicam.


UPDATE: Please disregard the above. I think I'm confusing ppi and dpi. Thanks again!

RobertJ
10-29-2004, 06:19 AM
.... the "printed" 72 ppi will be of less quality than the 180 ppi of the Canon G3 or the 300 ppi of the higher end cameras. Also, if I increase the ppi for printing at the suggested 300 ppi (as different books suggest for printing pictures), the software just adds misc pixels to make up the difference and that lessens the quality as well? ...

Cameras do not have "Pixels Per Inch" (or if this is quoted it is a meaningless thing to quote). Cameras take pictures with various numbers of pixels. The FZ20 can record an image with 2560 pixels horizontally x 1920 pixels vertically (2560x1920 = 4,915,200 pixels or 5 MegaPixels).

On most monitors images are viewed at the default resolution of 72 pixels per inch. So a picture taken at maximum pixels on the FZ20, would need a monitor over 35 inches wide to be able to see the full picture (ie.2560/72)

As for printing, you should be able to set you printer to print at varying ppi. On you example of printing at 300 ppi (which should be adequate for most print jobs) this image would print at 8.5 inches wide (2560/300). No pixels will be created or added by the printer in this case.

RobertJ
10-29-2004, 06:27 AM
.... As for printing, you should be able to set you printer to print at varying ppi. On you example of printing at 300 ppi (which should be adequate for most print jobs) this image would print at 8.5 inches wide (2560/300). No pixels will be created or added by the printer in this case.


ignore this as well Jazzisit.... i've just mixed my ppi and dpi as well :(

aaava
10-31-2004, 05:04 PM
First, lets look at the total number of pixels that are stored in the Z20:

2560x1920 = 4,915,200 (for example)

At 72DPI (which is what screen images all read), if you printed this out, you'd see noise, and if you display it on the screen you also see noise. This is because, at 72DPI, the pixels are really BIG.

If you know any Photo software, like Adobe Photoshop, you can convert the 72DPI image to something with more 'dots per inch', (where a 'dot' is equivalent to a 'pixel') and *then* print this resulting image out, with much SMALLER 'pixels', the noise will disappear. Also, just because your Canon stores the images at 180DPI, it still doesn't come *close* to the number of total pixels that the Z20 stores.

For instance, if, as someone stated above, you converted the image in Photoshop from 72DPI to 180DPI, you'd STILL end up with a much larger printable image than from the Canon you mention. It wouldn't be 32" x 27" or whatever, but it would still be much bigger, with equal quality to the image stored by the Canon. I haven't installed any of the software that comes with the Z20, (since I have Photoshop, and don't need it to manipulate images), but I'm sure there's a way in the image software to change the DPI to a larger number.

The point is that with really big pixels, of course it's going to look like there's more noise...even unacceptable noise...once you make the pixels 'smaller', this issue becomes less pronounced. Probably this was a marketing mistake by Panasonic, since photographers are more used to dealing with higher DPI numbers in the print industry, like 300DPI or so that is used for most magazines today...but that's all it is.

Of course, whether the Z10 is a better picture taker than the Z20 is another issue altogether. I'm a little concerned about all these posts about the noise (I've just purchased the Z20 after having a DISASTROUS encounter with a Canon Powershot S1 (P.O.S.)), and am a little confused...since the pictures I've seen thus far taken by the Z10 and Z20 look pretty indistinguishable on screen. Perhaps they've been 'touched up', with imaging software...which is fine, but I'd rather not have to spend time in Photoshop for every picture I take...

Hope this helps...

jazzisit
10-31-2004, 10:19 PM
aaava,

That does help....alot. I'm using Photoshop as well. I will try increasing the ppi/dpi and try printing them again. The prints I've made thus far has not been very impressive.

Also, can anyone tell me why the "greens" look so yellow? I have the saturation on low to no avail. Thanks in advance!

judge9847
11-01-2004, 09:44 AM
There are a lot of misconceptions in this thread. Rather than go to any length trying to explain the differences between pixels, resolution, dots per inch and pixels per inch, which has been done many times before, here's a link to an article which I think explains it all pretty well.

This article (http://www.fotofinish.com/resources/centers/photo/resolution.htm) is very thorough and to my mind deals with the entire subject very simply. If there are any questions about it, don't hesitate to post again and I'm sure someone will be able to help

As to the problem with printed colours I'm going to guess that the monitor hasn't been calibrated to work with the printer. Because printers and monitors use entirely different techniques and technology to get colour produced, they need to be told to work together so as to get what you see on the screen reproduced as closely as possible on the printer.

Several web sites offer the opportunity to do that and can be used but normally the Adobe Gamma Control Panel utility is best. Run that and then see if there's a problem still.

D70FAN
11-01-2004, 09:59 AM
aaava,

That does help....alot. I'm using Photoshop as well. I will try increasing the ppi/dpi and try printing them again. The prints I've made thus far has not been very impressive.

Also, can anyone tell me why the "greens" look so yellow? I have the saturation on low to no avail. Thanks in advance!

You need to adjust the hue. Saturation is the intensity of the color, hue is the color cast.