Noise in pictures

C

Cranky

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Edit My Images
Yes
Yep still learning :D

Can anyone tell me the reason for excess noise in my pics,

They seem fine in small sizes but the moment you zoom in it looks rough

tew0378004000194ej7.jpg


tew0378004000256ue4.jpg


tew0378004000212gg5.jpg



http://www.flickr.com/photos/si_crank/3003161701/
 
Hi,

I can't extract the EXIF info from your pics, but the two most important factors leading to high noise in images are:

High ISO speeds - say 400 ISO and above. This is particularly noticeable with camera set to ISO Auto, when the shot is made in low light.

Cropping image until noise is inevitable.

Other things that can cause noise, are oversharpening, adjusting incorrect exposure, over saturating, resizing etc. In other words, any manipulation done to a Jpeg will to a certain extent, lead to noise.
 
Hmm pretty sure the iso was set to auto, i'll try and edit the first post with exif info
 
There can be a number of reasons for noise.

First of all it depends on the camera, some produce "noiser images than others. However most modern cameras tend to have noise well under control

Second is sensitivity. If you are shooting at high ISO ratings, there is a lot of signal amplification going on. It's like static on radio and TV. The weaker the signal the more static or noise you get. So if you are shooting at high ISO 1600 etc, expect to see some noise. Some cameras are better than others at controlling high ISO noise.

Thirdly exposure. Under exposing and then compensating in image software will accentuate noise especial in the shadow areas.

Also excessive sharpening can make noise worse

Why does it seem worse at higher magnification, well simply you are enlarging the image and looking at finer detail, and the noise is in that detail.

OK but what can you do about it. Well there are noise reduction programes on the market, such as Noise Ninja and Noiseware. The latter has a free version available to download. OK it doesn't have the bells and whistles of the paid for version but it does an OK job, and I prefer Noiseware to Noise Ninja. Try them both and see which you prefer
 
Hmmm, i'll have to try choosing the ISO myself and do some test pics
 
If the ISO's are resonably low then how come there is so much noise?
 
What camera were they taken on?
 
*cough* Sony DSC-H2 *cough* :D
 
Looking at the images it's difficult to see the noise you are referring to. I've had a look on your flicker site but the resolution is too low to make anything out.All I can see are compression artifacts.
 
Let me see if I can put up a larger pic.....
 
....right back now, just took a straight crop off the original sized 6mp picture

gosm5.jpg
 
It's the shadow area that you are going to see noise. There is inherently less data there so it shows up more. I wonder if this is simply a characteristic of the camera.

If it is don't panic. Visit those very very nice people over at Imagenomic and download their free noise reduction software. Very simple to use and may help you pics

Here's the link

http://www.imagenomic.com/download_nwsa.aspx
 
Cheers fella, i'll see if that software helps, out of curiosity does anyone know if there is a test to see if the camera has dirt inside it?
 
Maybe someone can get some info from the EXIF I took from #3, Sorry it's not very expansive!!:thumbs::lol:. Kind regards Graham.

Standard Information
Make: SONY
Model: DSC-H2
ImageSize: 800x600
ComponentsConfiguration: YCbCr
CreateDate: 2008:10:28 14:04:25
ModifyDate: 2008:10:28 14:04:25
DateTimeOriginal: 2008:10:28 14:04:25
ExposureTime: 1/400"
Aperture: F4.0
MaxAperture: F2.8
ExposureProgram: Program AE
ExposureBiasValue: 0
CompressedBitsPerPixel: 8
MeteringMode: Multi-segment
Flash: Off
ISO: 80
WhiteBalance: Auto
FocalLength: 72.0 mm
FocalLength35efl: 72.0 mm
SceneType: Directly photographed
ColorSpace: sRGB
Contrast: Normal
Saturation: Normal
Sharpness: Normal

GPS Information

Other Information
Anti-Blur: On (Shooting)
BitsPerSample: 8
ColorComponents: 3
ColorReproduction: Standard
Compression: JPEG (old-style)
CustomRendered: Normal
Directory: C:\Documents and Settings\Graham Crowther\Local Settings\Temporary Internet Files\Content.IE5\0MPOF016
EncodingProcess: Baseline DCT, Huffman coding
ExifByteOrder: Little-endian (Intel)
ExifImageHeight: 2112
ExifImageWidth: 2816
ExifVersion: 0221
ExposureMode: Auto
FNumber: 4.0
FileModifyDate: 2008:11:07 17:23:43
FileName: tew0378004000212gg5[1].jpg
FileSize: 298 kB
FileSource: Digital Camera
FileType: JPEG
FlashpixVersion: 0100
ImageDescription:
ImageHeight: 600
ImageWidth: 800
InteropIndex: R98 - DCF basic file (sRGB)
InteropVersion: 0100
JFIFVersion: 1.1
LightSource: Unknown
LightValue: 13.0
LongExposureNoiseReduction: Off
Macro: Off
MaxApertureValue: 2.8
Orientation: Horizontal (normal)
Quality: Fine
ResolutionUnit: inches
SceneCaptureType: Standard
ShutterSpeed: 1/400
ThumbnailLength: 16909
ThumbnailOffset: 2982
XResolution: 72
YCbCrPositioning: Co-sited
YCbCrSubSampling: YCbCr4:2:2 (2 1)
YResolution: 72
 
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