How to guess what kind of noise levels are where?

[janwalker]

This is a question about evaluating an image in order to choose filter settings for it.

Profile Viewer: The profile viewer in Neat Image has an assessment of the noise characteristics of the image used to make the profile. [Yes?]

I'd like to know more about the definitions of the components and the values that are shown. Then, I'd like to know similar information about the the noise in the image being processed because I assume that would help me make better or faster decisions about the filter settings to use. [Yes?]

Question: Do you know of any tools or applications that would do an analysis like I'm asking about? I wonder what a graphical representation of spatial frequency would look like? (All we see currently in our camera or Photoshop histograms is magnitude of light-dark frequencies in different channels. No representation of spatial freq, although it is important to know when you want to use Photoshop filters like blur, hi-pass, or sharpening. Otherwise, you're just guessing.)

I'd like to see a "spatial" representation of spatial frequency! Like using the light/dark values to represent hi/lo spatial frequency -- even nicer if it were laid out with the XY axes being those of the image itself. So you would see in the image where the mid-frequency noise is. Or is that possible?

I love Neat Image but I have the feeling I could use it even more effectively if I could see which parts of my image were classified as being which spatial frequency.

I'd like to hear what other people do in choosing filter settings. I mean, what does very low spatial frequency noise look like in an image? And how do you know if you have "more or less" than the noise sample used for the profile -- which is after all a featureless uniform area. Or am I confusing spatial freq of the image with spatial freq of the noise? Help?

Is this comment/question explained OK?

Jan

[janwalker]

Maybe, at some level, the question reduces to asking what the meanings of "high" and "low" are.

[NITeam]

First of all, please check What is frequency?. Seeing these samples of high, mid and low, it should be easy to guess the next size: very low.

Then, please see Component Viewer, it will show the frequency and channel components separately so you will be able to make targeted adjustments of the filter settings.

Please note that the Component Viewer is currently available only in the Windows version of Neat Image. We are going to add it to the Mac version in the future updates too. In the meantime, you may want to simply try the Windows version (new Macs can run Windows) to see how the filter controls affect various components.

Hope this helps.
Vlad

[sternhagen]

To Neat Image Team:
I am presuming that Component Viewer and Additional Tools are not a part of my Mac version 4.5 as I can't find them in the interface nor in the March 27, 2008 manual—is that correct? Will they become a part of some future Mac version?
Regards
Sternhagen

[NITeam]

Yes, as I said, the Component Viewer is currently available only in the Windows version of Neat Image. We are going to add it to the Mac version in the future updates too. In the meantime, you may want to simply try the Windows version (new Macs can run Windows) to see how the filter controls affect various components.

Vlad

[janwalker]

May I suggest that Mac users are being somewhat ill-served by the Neat Image developers. We need the tools that you are describing in the previous messages. It seems a bit unfair to tell us to use tools that you do not provide.

Given both modern cross-platform coding techniques and the Intel based Macs, it seems feasible to me at least to code once and produce twice, in order to keep your versions in parallel for the two main platforms used by photographers. I don't have the money to buy a new Mac in order to buy and install Windows in order to use the Windows version of Neat Image and then port the result back to the Mac environment in order to continue using Photoshop (which I would not be using under Windows.)

How might we Mac users help you to raise the priority of our needs in your product development plans?

Thanks for any suggestions.
Jan Walker

[NITeam]

We started to develop the Mac version later than the Windows version so it is not surprising that some features from the original Windows version are not yet implemented. We are working on this and future updates of the Mac versions will become closer to the original Windows version.

We listen to our users and in the first place implement those features that are most frequently requested. The features we discuss in this thread are relatively infrequently mentioned. Still, we have them in our development plan and they will be implemented in one of the future updates.

Vlad