Excessive noise when editing in PS RAW

[avz10]

I have a Canon EOS 450D and learning Photoshop (CS5)

I take my photos in RAW and do most of the editing in PS Adobe RAW. I save the edited photos in jpeg format, but keep the originals. My computer crashed and I am not sure what I do wrong, but there is a lot of noise when I use a photo as a desktop background.

Editing:

Background (the noise does not show up very well in this screenshot):

Picture data:

Any advice please??

 

[Tony S]

What are the pixel dimensions of the edited photos you are using? If it's only 72 dpi and set at something around 640 on the long side it's going to be noisy, it really helps to use images that would have a similar pixel count to the size of your screen as a background.

 

[Bend The Light]

I had this problem a while back. The issue was using BIG files as desktop. The desktop (Windows) had to compress/reduce the file, and it did it badly. I realised later that using a file over 4 or 5mb would cause a problem. And the 10mb I tried once was awful!

Try resizing the image in PS, using edit, image size, and set it to a similar size to your desktop. You might also want to change the colour profile, too...to sRGB and the colours will show properly on all applications, whereas aRGB is not recognised in some (like internet explorer).

 

[avz10]

This is where I get stuck!

This is the pixel dimensions:

This is the image at 100%

Hope this helps

 

[Bend The Light]

No point having 600ppi, I don't think.

For my screen I would change the pixels/inch to 100 (which is what my screen is...yours might be similar), then change width to 1366 pixels, and/or height to 768pixels, which are the dimensions of my screen.

Try that, then save as JPG and set as background.

See if that works.

 

[KmH]

The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

You have several ACR sliders all jacked up that are making the noise recorded in the original capture more visible.

Here is another truism many don't know about, any edit (even parametric edits) degrades an image to some extent. If you do many edits the degradation gets worse with each one.

FWIW, I see your ACR color space is set to Adobe RGB. I do all my edits in the ProPhoto RGB color space because virtually every image editing book I have read explains why Prophoto RGB is better to use for editing.
Bruce Frasee, Jeff Schewe, Martin Evening, Dave Cross, Scottt Kelby, Tim Grey, Doc Brown, blah, blah, blah)
It's a 4272x2848 pixle image, which is likely way bigger than his computer display. I use a 22" display and it can only show 1600x1200 pixels.

The Brightnss slider only effects the mid-tones, but so does the Clarity slider so you have double dipped.

Use the Exposure slider to set the white clipping point (look at the histogram, or hold down the Alt key as you move the Exposure slider)

If the original was under exposed use the Adjustment brush and/or Gradient tool locally in the photo rather than doing global edits.

 

[Bend The Light]

The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

How so?

If my screen displays images at 100ppi, with a pixel size of 1366x768, and my image is saved at 100ppi with a pixel size of 1366x768 then surely that is a 1:1 ratio and the image will display without any resizing, and without any "made up" data to display pixels.

If i make the image 50ppi, at 1366x768, then each pixel on my screen is going to display 4 pixels for each pixel of the image, in effect stretching the image in both directions. This would lead to blocking?

If I make the image 200ppi, at 1366x768, then 4 pixels (in a rectangular array) on my image would need to be displayed by 1 pixel on the screen...the software would have to decide which colour to display if those 4 pixels were different colour.

In each scenario, surely some image degradation would occur?

I'm not an expert, all I said above could be wrong, and I'm sure someone will tell me that. But it seems logical to me.

Also...I did have a problem with large file sizes displaying poorly on Windows Image Viewer, and in Facebook, and a couple of other places. It was solved very easily by reducing the images a size and resolution to match my screen so no resizing occurs. And for Facebook etc., making them 800px longest side so the Facebook algorithms for resizing didn't screw it up.

Cheers

 

[Robin Usagani]

Do not resample. You are telling the puter to add (interpolate) pixels.

 

[Robin Usagani]

No, that only applies to printing. For electronic display, it just cares about the pixel size. Each pixel goes to each pixel on your monitor. Thats it. If you are talking about the display on editing program like photoshop, yes... ppi will matter I believe.

The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

How so?

If my screen displays images at 100ppi, with a pixel size of 1366x768, and my image is saved at 100ppi with a pixel size of 1366x768 then surely that is a 1:1 ratio and the image will display without any resizing, and without any "made up" data to display pixels.

If i make the image 50ppi, at 1366x768, then each pixel on my screen is going to display 4 pixels for each pixel of the image, in effect stretching the image in both directions. This would lead to blocking?

If I make the image 200ppi, at 1366x768, then 4 pixels (in a rectangular array) on my image would need to be displayed by 1 pixel on the screen...the software would have to decide which colour to display if those 4 pixels were different colour.

In each scenario, surely some image degradation would occur?

I'm not an expert, all I said above could be wrong, and I'm sure someone will tell me that. But it seems logical to me.

Also...I did have a problem with large file sizes displaying poorly on Windows Image Viewer, and in Facebook, and a couple of other places. It was solved very easily by reducing the images a size and resolution to match my screen so no resizing occurs. And for Facebook etc., making them 800px longest side so the Facebook algorithms for resizing didn't screw it up.

Cheers

 

[avz10]

Hi all

Just to get it clear. KmH advises me to use ProPhoto RGB. What should the other settings be in Adobe Camera RAW? (Settings disdlayed in this screenshot are Depth; Size; Resolution and Sharpen)

Or what are the settings for general use in RAW and PS itself??

Thanks

 

[Robin Usagani]

Doesn't matter what you put. Only matters if you want to print it.

 

[KmH]

The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

Let me repeat that.....The PPI value is meaningless for electronic display......

How so?

If my screen displays images at 100ppi, with a pixel size of 1366x768, and my image is saved at 100ppi with a pixel size of 1366x768 then surely that is a 1:1 ratio and the image will display without any resizing, and without any "made up" data to display pixels.

Do the math - 1366 pixels divided by 100 pixels-per-inch = 13.66 inches. The pixel units cancel leaving only inches, which is why PPI is only meaningful for prints, and only the pixel dimensions are meaningful for electronic display.

Pixel density - Wikipedia, the free encyclopedia

 

[KmH]

Or what are the settings for general use in RAW and PS itself??

Thanks

I'd say you and Bend The Light need some good reference materials:

Real World Camera Raw with Adobe Photoshop CS5

Adobe Photoshop CS5 for Photographers: A professional image editor's guide to the creative use of Photoshop for the Macintosh and PC

Real World Image Sharpening with AdobePhotoshop, Camera Raw, and Lightroom (2nd Edition)

Here is some other good info: http://wwwimages.adobe.com/www.adob...ly/prophotographer/pdfs/pscs3_renderprint.pdf

 

[Bend The Light]

Do the math - 1366 pixels divided by 100 pixels-per-inch = 13.66 inches. The pixel units cancel leaving only inches, which is why PPI is only meaningful for prints, and only the pixel dimensions are meaningful for electronic display.

Pixel density - Wikipedia, the free encyclopedia

Right, so I have my image at 100ppi, and this time the image is 2732 x 1536 pixels in size.

Doing the mathS I get 2732 pixels divided by 100ppi = 27.32 inches. So my image is twice the width of my screen.

So I make my screen show that image by asking the computer to reduce the image in size to fit. the screen still only has 1366 pixels to show that image width, but it has 2732 pixels to display per line.

My question is...how does the display program know which one pixel out of two to throw away? Or merge? Or whatever?

Something must give somewhere...some colour, or sharpness, or something must change.

 

[Robin Usagani]

If you show that as a desktop wallpaper, you wont see the whole thing unless you pick the stretch option. If you are on photoshop and you click on display print size, same thing. I you pick display to pixel size, then it will be even be more zoomed in assuming your screen is 72ppi.