How can I explain to others?

[Jaffa]

I love the noise reduction in Affinity Photo.  Just recently I used 395% on a girl's face and it worked beautifully.  Now we all know that in practice you can only have 100%,  so the scale must be different in some way.  What is 100% based on in Affinity Photo?  Is that the measure to which some other programs can only reach to?   

When I am singing the praises of Affinity Photo to others how do I explain this?

[jkehoe]

Hi Jaffa,

I had to try this myself to see what you meant since I didn't know that we could push a denoise value beyond 100%. I see now that when adding a Live Denoise layer I can click / check the "Extreme" checkbox in either the Luminance or Color sliders and only then can I move the slider well past the 100% value. The Contribution slider stops at 100%; there's no Extreme checkbox on my Affinity Photo 1.6.7.

 

I browsed through the pdf download of the Affinity Photo manual and couldn't find an answer to this so I did a web search on "Noise Reduction" and among other hits I found this one on RawPedia:

https://rawpedia.rawtherapee.com/Noise_Reduction

 

What's interesting to me is that some of these software tools add pixels to our image and, perhaps, pushing the value in excess is similar to exceeding the recommended maximum that the software recommends? When I tried high values on a few images I did see some very strange results that were impressive but strongly altered the image in such a way that I found comical.

 

Let's see what other folks say about this topic.

 

[firstdefence]

There is a point, when using the extreme options where the effect drops off, a kind of diminishing returns, The point I got to with this was approx 200% +/- 20%

If you zoom in on a face and move the slider to around 200% the skin and general details will soften, if you move past this, you can push to 700-800% with little additional denoising, the odd pixels will jiggle about but the majority of denoising will have been done.

[firstdefence]

An example of what I've just said.

At the 800% the image is degrading and smooth tones are breaking up but overall there is little difference.