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Marty Hudzik May 20th, 2013 07:52 AM

help retrieving highlights with WDR preset
 
Guys. I shot my first event with the c100 this weekend and things went pretty well. However, I used the WDR preset and even though I did not see any zebras on the screen, some of my highlights are a little hot. This was a dance competition and several of the dancers are quite pale. As such, their faces seem to be a little overexposed and details are slightly lost.

I guess I am wondering if there is a good technique to try to retrieve some of these details. Using most of the tools that I usually use, I have not been able to pull this detail back. I realize there is a chance that it is lost. But since it didn't really show zebras on the camera....I am thinking I might be able to recover it still.....at least improve it somewhat.

I have read on here that some users like to overexpose and pull the image back as it is cleaner than underexposing. I typically do not do this....but I am stuck in an odd situation at the moment.

Thanks.

Bob Willis May 20th, 2013 10:12 AM

Re: help retrieving highlights with WDR preset
 
What do you have the zebras set at?

When you loose detail from overexposure that detail is lost. Even when shooting raw highlights that are overexposed can be completely lost.

Marty Hudzik May 20th, 2013 11:56 AM

Re: help retrieving highlights with WDR preset
 
the zebras were probably set at 100. I know that when things get blown out they are usually lost for good. This stems from the fact that the camera was largely unmanned during the show and the exposure on the stage might have been changing. They were using just white lights so no color issues. Based on the angle and distance of the camera, the faces are very small.....as such they zebra pattern might not have been visible in the little spots on the LCD screen to know it was overexposed.

It's not terrible but it's a little bright. Seeing as the final deliverable is DVD, I am not sure this will be an issue at all.....but I was hoping to tweak it a little and don't know what the best way is to just dial down the skin tones really.

Thanks.

Seth Bloombaum May 20th, 2013 07:04 PM

Re: help retrieving highlights with WDR preset
 
This might better be answered in a forum for your particular NLE - what do you cut with? And what have you tried...

On Vegas, I'd probably start with Color Curves, then maybe the Secondary Color Corrector. I really like curves for correcting brightness/contrast kinds of issues, because it gives control where I want it, and really works well to decode various flat picture profiles.

IMO, it's much better to underexpose (a little), than overexpose at all. Good post corrections can pull out some underexposure pretty well, with a look I like.

But Zebras set on 100 is a bad way to gauge most exposure. What we care about is faces, and as a rule of thumb, exposure should be set so that caucasian faces show highlights that hit somewhere around 75 or 80; I set Zebras there when shooting people.

If you do have significant white in the scene, or specular highlights on shiny objects, that's when to pull out Zebras at 100. Faces not showing zebras 100 could mean they are exposed to 98 or 50. Doesn't really tell you much.

Marty Hudzik May 20th, 2013 07:59 PM

Re: help retrieving highlights with WDR preset
 
Thanks. I didn't really anticipate the skin tones to be so hot or I would have backed down the zebras. You live you learn I guess. I'll just work to salvage the best I can in this project. The latitude I was seeing on screen seemed so great compared to my xlh1 that I didn't give it the attention it deserved on site.

Marty Hudzik May 21st, 2013 09:53 AM

Re: help retrieving highlights with WDR preset
 
You know......I am not even sure this is not a software issue. When I view the clips in Premiere CS5.5 the highlights seem to be clipped. However I just viewed the same files using VLC media player and the highlights seem fine. Some google searching seems to indicate that in older version of Premiere it could mishandle highlights like this. I need to do some more digging. Thanks for all the ideas.

Matt Davis May 22nd, 2013 10:08 AM

Re: help retrieving highlights with WDR preset
 
I'm a little shy of Premiere with 109% highlights.

Premiere is a strict 100% tool, so if you shoot with super-whites - 109% rather than 100% - you need to take action. That's where I check out back to FCPX, as I was using ProcAmp to lower things a bit. There is a reason, Adobe Premiere Editors can explain, I check out with 'Thank you but no' only because I've spent too much time in FCPX to be happy in Premiere Pro.

There's two options here: take your AVCHD clips through 5DtoRGB to map the highlights to a 100% space by mapping them into ProRes - and do a nice sweet trick with the chroma at the same time - to make edit ready rushes that any NLE would love - but this takes a lot of time... OR... let your NLE deal with it, and FCPX says 'this is interlaced!' which it isn't, so you need to switch its interpretation (I believe the same is with Premiere Pro with native footage). I believe Avid deals with things in a similar way, sorry, can't report on it.

I'm a great fan of using a 109% range and using zebras to flag 100% clip. WDR is as close as you get to a 'do it all' profile which requires minimal correction. When you use C-Log, you're going to do some curves on every shot and thou shalt not over expose - use the monitor cheat to ensure you don't 'help' it. I believe it's the Canon noise reduction built into the C100 codec software that means you can pull more out of the shadows than you'd expect from AVCHD, which leaves the highlights to roll off so orgasmically. Every shot needs careful tweaking with C-Log. WDR is a lot more forgiving and flexible in post if you're doing fast turnaround stuff. You can get a great picture with a little play time and a copy/paste approach to grading.

But of course YMMV. LOL.

Ben Giles May 22nd, 2013 12:58 PM

Re: help retrieving highlights with WDR preset
 
Hi Matt.

You mention, "There's two options here: take your AVCHD clips through 5DtoRGB to map the highlights to a 100% space by mapping them into ProRes - and do a nice sweet trick with the chroma at the same time - to make edit ready rushes that any NLE would love."

What settings are you using with 5D to RGB? I have a beta copy of their 1.5.14 version to evaluate. I have been using FCPX to ingest for the past few months, as it gives me the advantage of a UID, which can then be matched up if I pull the AVCHD clip out of the archive at a later date.

However, are you seeing a significant advantage in the way that 5D to RGB transcodes?

Cheers,

Ben.

Matt Davis May 22nd, 2013 01:19 PM

Re: help retrieving highlights with WDR preset
 
I'm not seeing an advantage that I can't correct for.

So, people who don't want to futz around with their levels, and just want rushes they can edit and play with in a format that's edit-friendly will get a lot of value from 5DtoRGB. Especially if they've not used a Ninja or other 4:2:2 recorder and just want solid rushes that won't misbehave.

But... if you're cool with the 109 and C-Log thing, are happy with global/block colour changes on rushes, have plugins such as Tonalizer, Levels and Magic Bullet Looks, maybe you'll be happier with the base rushes ingested into something like FCPX.

I am known as an FCPX hater who switched to Premiere Pro. I am now switching back again (again). Sorry to any followers for the confusion. WDR and the FCPX Color panel are actually working really well together, and I only need help from other plug-ins when things didn't go quite according to plan.

But... if I were doing my own movie, I would still probably take all my rushes through 5DtoRGB - Premiere Pro, FCPX and FCP seem to ignore all my metadata, it does a great job on Chroma and Luma info, and although it takes its own sweet effing time, the results are rock solid. I wish I could take all my rushes through it.

Ben Giles May 22nd, 2013 01:36 PM

Re: help retrieving highlights with WDR preset
 
Fine to be an NLE tart - I'm currently not talking to FCPX, but will probably relent when it treats me like a princess and buys me things.

Ahem...

Might have taken that too far.

Ben.


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