correcting overdetailed / sharpened footage

Mindmatter wrote on 5/11/2015, 3:42 AM

Hi all,

I recently rented a sony PMW 320 for a small documentary. I had rented it before from the same company, no problem. When I looked at the footage later, I was in for a bad surprise...everything was totally overdetailed, noisy, with lots of ugly, video like contours that sometimes look like chromatic aberration.
I had kinda sensed something was odd as the peaking was almost impossible to dial in without the peaking effect hijacking the whole screen...I later realized it had reacted to the added sharpness, but initially thought it was somehow just not working as it should.
So I had a deeper look at the menu, which, I know I know, I should have done beforehand. So someone had created a "lens setting", which I'd normally call a picture profile, but had named it "standard". I had checked that before filming, but wrongly assumed that it was the standard sony profile for that cam, namely neutral. So, someone had created a setting with the detail up 60%, and some other atrocities, resulting in the mess I'm in now. I only now realized that the actual "standard" profile is at the very bottom of the list , and is called " standard" , duh.
Ok panic aside, what would be the best approach to get rid of at least some of the artifacts, I know i won't be able to totally save the footage, but still... unsharp mask with negative value? Sony soft contrast plugin?
I'd be really thankful for some good tips on this.
Thanks!

Comments

ushere wrote on 5/11/2015, 4:42 AM

don't know about video that's oversharpened, but i had some clients stills to use that had been 'manipulated' by the office receptionist to look like sandpaper and managed to 'soften' them to a usable quality just by using a little gaussian blur (very, very little).

give it a go on a test sample - you can't lose anything ;-)

musicvid10 wrote on 5/11/2015, 4:49 AM

No it cannot be reversed, maybe mushed a bit as ushere suggests.

Any rental company that doesn't reset everything on return should be avoided.

johnmeyer wrote on 5/11/2015, 1:43 PM

I'd have to see a clip to offer informed advice. However, most sharpening works by putting a thin halo around sharp light/dark transitions. Over in the doom9.org AVISynth forum, quite a few people have developed "dehalo" scripts that attempt to eliminate these halos. They do work, but only to a modest degree.

musicvid10 wrote on 5/11/2015, 2:14 PM

In addition to piping, high pass filters cause data loss by blowing pixels.
That's what is unrecoverable to the extent that it occurs.

wwjd wrote on 5/11/2015, 4:20 PM

I vote mess about with SONY SOFT CONTRAST. Especially the Diffusion slider. Can't really fix bad footage, but maybe you can distract with some glow or something. :) depending on final need look, of course.

larry-peter wrote on 5/11/2015, 4:55 PM

You may also try a pass through Neat Video with sharpening turned off. The image softening you get from NR using a noise profile may help, and the temporal noise reduction will help with the sharpened camera noise.

And although I am not proficient with Convolution Kernel (even explaining it) you may try starting with the blur preset and playing with the matrix. I always use it for sharpening now, rather than Sharpen or Unsharp Mask and the results seem better to me. It may be able to undo a portion of the sharpening damage.

A quick test with a over-sharpened low-res photo, followed by a Gaussian Blur with only green channel checked (very low setting - I used .0016 for both horizontal and vertical) put me back very close to where I started.

musicvid10 wrote on 5/11/2015, 5:21 PM

Atom 12 is correct that unsharp / kernel does not over sharpen because it is a low cut filter.
More subtle, but safer for the highlights.

fldave wrote on 5/11/2015, 10:35 PM

I've had some luck with
a) duplicate track
b) mute top track
c) lower track add gaussian blur to a nice smoothness, not too much
d) top track, unmute and adjust opacity down to a level that makes the full image bearable. 60%-40% is not unheard of. You want to balance the smooth background with some crisp top track elements.

It sometimes makes harsh footage watchable.

Mindmatter wrote on 5/12/2015, 1:39 PM

Thanks very much to all of you!
I will definitely try out all those options once I get to the editing.
On the positive side, at least I found and could get rid of the problem for the following shoots...
I'll post the results as soon as I'm on it.

harryfear wrote on 3/14/2018, 8:22 AM

I'll post the results as soon as I'm on it.

What did you find worked best in the end? Any results to show?

@Mindmatter

Mindmatter wrote on 3/15/2018, 3:01 PM

Harry -that's a long time ago... :)
I vaguely remeber softening it ever so slightly, but the shot was pretty messed up. The double track thing Dave proposed did not seem to save much of it, it was probably too far gone already. Had to live with it.