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cadu82
09-17-2005, 09:19 AM
Just a guess. Looking at the sample of the church from s9000 and putting together with the same from 350xt and sony R1, the s9000 sample seems to achieve more details (windows above statue ,clock, etc...)although in the corners the picture is blurry with clear lost of quality and detail.

Shooter
09-17-2005, 10:44 AM
I've been looking in Photoshop at them. The purple fringing is quite visible, but at the same time I don't know if I am zoomed in unreasonably when I see it. I suppose it is necessary to print a full 9MP image at 9*12, then a cropped half size image at 9*12, then mabe a cropped .25 image at 9*12. My onscreen judgement suggest that the last one starts to have the fringing become visible. I guess when the sites have real reviews up they will explore these things.

Shooter
09-17-2005, 11:25 AM
I've finished looking at them in photoshop at least for now.

For these particular images I've decided that the purple fringing / chromatic aberration is not acceptable for the cropping that I would like out of 9MP. If you can crop half width and half height, you are left with 3MP, which is enough for 9*12 at 150 ppi which in my opinion is fine. However when I do this the CA is visible on inspection.

The resolution seems good to me however as well as little distortion. I don't see the edge blurriness that much.

CA is correctible in photoshop but I prefer to limit the requirement to do these things, ie I don't mind occaisionally but my hope for the cropping above would require it on all images with white/black contrast.

They seem like good images but with a few issues. Therefore I am not convinced yet.

Does any of this make sense? :)

cadu82
09-17-2005, 11:51 AM
Hi there shooter. Im not an expert, but i think that the CA is because of the lens that is not that good.Maybe you could give some advice about printing since you look like a photoshop user.In the web most people consider
less then 300 dpi not acceptable for photos .Do you have experience to give some advice...Thanks

JTL
09-17-2005, 10:26 PM
The whites are blown out in a few of the samples...could probably be controlled in camera, though...

Merlin
09-17-2005, 11:17 PM
the images seem very.. soft..

Shooter
09-18-2005, 11:52 AM
Hey Cadu,
If you have photoshop CS2 then removing CA is as simple as applying a filter (filters - lens correction or something similar). The problem is you have to apply it and check it out several times. The CA could indeed be caused the lens which is probably fine in terms of quality but a bit aggressive in terms of focal range. It can be limited by some techniques both in taking the pictures and in processing, but I am not overly impressed by CA on this camera.

About the 300 ppi, well everyone is entitled to their opinion but mine is that this figure was created out of thin air by camera industry types to ensure that people have a reason for upgrading their camera every 2 years. Some research has shown that the limit of human perception is around 100 lines per inch. However, test on people with images have shown that people can distinguish greater sharpness, for example correctly sorting a stack of photos printed from 100ppi to 300. I am not convinced that these studies were done properly and 'double blind'. For example if you use the same image and change the cropping or zoom factor peoples perception will change regardless of the ppi, and there are also printer issues.

Anyways... In my personal experience a handheld photo at 200 is fine and a wall photo at 125 is good... I have a print of 125ppi from a 4MP image which is just under 16*20 inches... it looks great.

Another thing I should add: "these images are too... soft" is a practically useless statement. I have a feeling Merlin only looked on screen:

Now that images are getting so big, computer screens cause more harm than good when looking at quality. It does not do justice to zoom in to the native resoultion of your screen, and neither does it do justice to zoom out and see the whole image. You need to be particularly careful not to use internet explorer to judge quality. Because assuming an onscreen ppi of 100, looking at a 9MP image on the internet is the same as a print of roughly 36 inches across. Better stand back a bit before you start criticizing. The way to judge quality on screen is to match an image resolution for the cropping you want with your screen resolution then step back so that the image is approximately in correct size perspective. If you want to see what a 5*7 will look like at 200 ppi, put an image at native resultion on your monitor (~10*14 inches of the screen) and step back so the image size on screen is the same as a 5*7 held at arms length. (This is what you did right Merlin?).

Basically don't trust image quality statements unless it is from someone with a consistent methodology.

Anyway. Back to the S9000, I had hopes that you can crop down to one quarter of the image (half height and half width) and still have a good 8*10 or 9*12 handheld images or even 12*18 inch posters. I'm still looking at more images and hope to take some of my own to get the CA figured out.

Keep in mind what you're paying for this advice though!