Why the noise?

[dk]

I seem to be having some problems with noise in my photographs; for example, the first one I've posted here shows some evidence of noise in the upper-left corner at 100 percent. Here is the EXIF:

Nikon D70
2006/01/23 18:13:15.9
JPEG (8-bit) Fine
Image Size: 3008 x 1002
Lens: 18-70mm F/3.5-4.5 G
Focal Length: 44mm
Exposure Mode: Manual
Metering Mode: Spot
1/200 sec - F/4.5
Exposure Comp.: -1.3 EV
Sensitivity: ISO 200
Optimize Image: Vivid
White Balance: Auto -1
AF Mode: AF-S
Flash Sync Mode: Not Attached
Auto Flash Comp: 0 EV
Color Mode: Mode IIIa (sRGB)
Tone Comp.: Auto
Hue Adjustment: 0°
Saturation: Normal
Sharpening: Auto
Image Comment:
Long Exposure NR: Off



I don't see anything there that would cause noise unless my using a UV filter (blue by the way...hmmmm, I wonder if that is adding to my blue tint?)

As for the second shot, I just thought I'd throw it in the mix to get your thoughts.



Thanks a million.

dk

[xerubus]

both photos are good .... regarding the noise perhaps it's to do with the jpg compression settings you are using?

cheers

[Mal]

Not sure about the noise question in photo number one.
However I like picture number two. My only thoughts are that we can see your shadow in the water and this takes a little something away from it.

[rog]

The only real noise i can see in the first shot is due to jpg compression. Whether this happened in the camera, or as a result of cropping and saving again, or both, I don't know.

Apart from that, it could just be the limits of 8-bit colour that you're seeing some slight posterisation of sorts in the snow against the sky.

- R

[frink]

Exposure Comp.: -1.3 EV

Did you underexpose in camera and then push it back in processing the NEF?
If so that would explain it..

[dk]

Thanks for the comments. I am ever willing and able to learn. Now to address some of the questions that came along with your comments:

Jpeg compression; I was shooting in fine.

Mal, I know that looks like my shadow. I thought the same thing when I first saw it myself. In fact, it's a patch of blue sky visible through the clouds. I checked my other images and found the same darn thing. I guess I could/should photoshop it out. I agree, it is very distracting.

frink: I think you've solved my noise problem. Definitely underexposed; not by a lot but enough. I've been fighting this blue tint issue when shooting in snow and read somewhere online that setting the EV -1.3 would eliminate the blue tint. It looks like it did the trick but at the expense of having to deal with noise.

Again I'm grateful to you all for your comments.

Thanks a million.

dk

[leek]

Jpeg compression; I was shooting in fine.

While it's probably not the cause of your noise issue, no matter what JPEG mode you were using, it is still heavily compressed. Also when you resize for the web, resampling and possibly further compression takes place... The in camera compression will cause image information to be lost and the PC processing will cause further loss of information.

Do yourself a favour and shoot in RAW format - you will capture so much more detail in your images and will have much more control over your exposure and white balance in post processing.