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So i'm trying to get some quality pics with my Canon S3 IS, but no matter what ISO I use, and what lighting condition, the images always have artefacts or coloured noise in them.

I've got the CHDK firmware mod on it which allows me to run scripts and shoot in RAW mode, so that should cancel the effects of JPG compression artefacts. Regardless of whether or not the hacked firmware is loaded it still gives me similar results.

Here's a blown up look:

post-256-1204528261.jpg

Here's the EXIF data:

post-256-1204528297.gif

Full image resized with some noise reduction:

2306991960_0297e29fda_o.jpg

RAW file (converted to Digital Negative DNG file)... right click and save as:

http://www.superfunhappysliders.com/images/CRW_1502.DNG

Does anyone have any ideas on what I'm doing wrong?

post-256-1204528261_thumb.jpg

post-256-1204528297_thumb.jpg

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Have you set the compression to fine in the options? About the only thing that I can think off.... Used that very camera for a good while and didn’t have any issues like that... Could also be your pc as it looks like it’s not blending the pixels, when I zoom into my pictures it’s also showing the picture pixelated like that but changes to smooth in about 1 second. My first sugestion would be to try the same pickture on another pc if you haven't yet

Edited by bnr#@

Seems strange, that is definitely a bit too noisy for ISO 75.

*has a look at the DNG*

Alright, I've done a bit of research on you camera. The noise levels you're experiencing are pretty much normal for that sensor. It's small, and noise is a unfortunate result of that.

I believe the S3 IS has noise reduction settings, try them out. A lot of the time though you'll find the noise reduction filters will kill image detail and quality. Software noise reduction options do a pretty good job and might be an option for you in your post processing workflow.

DPReview has some good sample shots from your camera model: http://www.dpreview.com/gallery/Canon_s3IS_samples/

So, you can either live with the noise, fight the noise or buy a new camera. :D

you have taken a photo then tried to crop out a tiny little part of it - maybe 5% of the actual image, and then tried to blow it up big

it is just all pixely

if you printed the original photo at 8x10inch or even 16x20in you wouldnt see that noise

if you just wanted a shot of the grill of the GTR, you should have walked over and taken one, Photoshop cant put detail in that wasnt captured in the original image

you have taken a photo then tried to crop out a tiny little part of it - maybe 5% of the actual image, and then tried to blow it up big

it is just all pixely

if you printed the original photo at 8x10inch or even 16x20in you wouldnt see that noise

if you just wanted a shot of the grill of the GTR, you should have walked over and taken one, Photoshop cant put detail in that wasnt captured in the original image

the blow up was a chunk to show the amount of colour noise that's in the photos. Usually when you blow up a picture there's blurring or antialiasing, but no colour noise like that. the point I'm trying to make is that the colour noise is quite visible with no zoom applied. Of course I'd take a pic of the grille closer up if that's what I wanted a pic of.

Yeah for 75 ISO on a nice bright outdoor setting that's way too much noise... I'm suspicious that the sensors panel's got something wrong with it.

I turned off the internal noise reduction settings to capture a raw image at full quality and then wanted to do the noise reduction by hand to try and retain as much detail... might try turning it on and see if that's any better. I really wanted to do some macro shots, and that much noise can ruin those kind of shots. Night shots are a nightmare also with all that noise.

having never used an S3IS it may be normal for that model

Canon did issue a recall a while ago for a camera with a CCD problem- i cant remember which model it was though i am currently trying to find out though

my Cameras are a Canon 350d and 1dmk2n - both of which are 8mp DSLRs with a fairly large sensor.

i work for a camera repair facility here in perth and am constantly surprised at what some point and shoot cameras produce.

stuff my colleagues call "normal" from some cameras, wouldnt stay on the memory card for more than a minute or so if i took it with my camera.

Pixel size and density affects image noise.

a large sensor of the same Megapixels as a smaller sensor will nearly always produce cleaner images because of the lower pixel density and lower buildup of heat (the actual cause of the noise) CCD sensors are normally also noisier than CMOS sensors (your camera will have a CCD type sensor)

i am currently downloading the DNG file to have a closer look

EDIT - those pics actually look pretty clean.

i have seen much worse photos come out of some of the cameras at work, and some of the photos that a friend of mine did at my wedding are really noisy, even at 100ISO

a little bit of noise ninja or lightroom's noise reduction and they will look a little better.

and the noise reduction bit in the camera still works with RAW files, it does a dark frame subtraction to long exposures - so even with it on it wouldnt have helped this photo

Edited by Echo63

Like I said, that amount of noise seems pretty normal for that camera (even on those settings). If you want less noise you're going to have to get a new camera (something with a larger sensor -- this usually means less noise).

That seems about right for a camera of that range. If you wanted better you'd prob have to upgrade camera and get something with a better/larger sensor.

Also, comparing the original to the crop you've zoomed in quite alot. Thing is though, even if you had no noise in the crop the pic is still extreemly pixelated so getting rid of it would be of little benifit.

  • 2 weeks later...

Thats totally normal for a S3 Shan...

Unfortunatlly thats about the best you can do with a CCD, Cmos is the next step in compact digital still cameras, coming next year...

Already great examples in the current DSLR range of what a Cmos sensor can do...

There is also new CMOS technoligy coming to DSLR, with a sensor that has a "gapless micro lens" over each individual diode...

Currentlly on demonstration as the eyes of the Canon HV20 & HG10 HD Camcorders...

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