Lugarimo wrote:Can some clarification be added about these new features?
Yes, more details are available in the user guide of Neat Video 4. Please read the corresponding sections of the user guide to learn more about those new functions.
"Dust and Scratches" filter to remove film scratches, dust, impulse interference (more...)
How does this work? Will these scratches and dust have to be in the noise profile
Quite the opposite, it is best to not include them into the profiling area. That is also described in the user guide.
Lugarimo wrote:will NV automatically try to detect and remove the scratches and dust?
It will. And there are adjustments in that Dust and Scratches feature that allow you to control the way it works.
Lugarimo wrote:If so, should the mechanism be trusted not to find false positives and damage the picture?
It is pretty good in my opinion. I recommend to try it and see if you can trust it.
Lugarimo wrote:I prefer NV to just remove noise
That is fine too. Did you already try NV4? It should very easy to see there that all those new filter sections are really optional.
"Slow Shutter" mode for video containing repeated frames (more...)
Can we have more details, how does this work? Are the frames detected as repeated removed and replaced? I have videos with frames that are not duplicates that NV 4.0 said they are likely duplicates. Should I be worried?
Nothing is removed nor replaced. That feature simply allows the noise filter to work more accurately in presence of repeated frames.
If NV says that some frames may be repeated then it is worth taking a closer look at those frames. Some components may in fact be repeating. For example, please see the second clip here
. The useful content of the frame does change every frame, but the noise component doesn't change every frame. That is one of the cases of repeated frames (repeated noise in this case) where the Slow Shutter mode can help. You can see why in that example too. The case "Filtered not using Slow Shutter" corresponds to NV3 (or NV4 not using Slow Shutter), while "Filtered using Slow Shutter" clearly show this new feature of NV4.
If you do not have such kind of problems (of noise not being fully reduced in presence of repeated frames) then you probably do not need to use this feature. After all, it is optional and should be used only when it is needed. Hence I see no reasons for worries.
"High Quality" mode for better detail preservation and sharper image (at the cost of reduced processing speed: 1.5-4 times slower)
Is this the same high quality option of the last versions? I've always had them enabled by default.
No, it is a new feature too. The old High quality option did not change the speed so much. This new feature does in fact do much more work trying to discern the finest details to better preserve them. Sometimes that actually helps to get better visual results, but that depends on the clip. However the processing speed is quite reduced so it makes sense to run some tests on a small part of a clip before choosing one setting of that option or another. Otherwise you may spend much more render time without a significant improvement. But if you do see some improvement then you can decide to spend additional render time.
Lugarimo wrote:You should add before/after examples that demonstrate the better denoising quality of NV 4 vs NV 3.
We added new examples showing the features that were not present in NV3 (Dust and Scratches, Slow Shutter). Showing the difference of the regular noise filter is a bit more tricky but we will probably add that later too.