Tag Archives: LUTs

HPA Tech Retreat — Color flow in the desert

By Jesse Korosi

I recently had the opportunity to attend the HPA Tech Retreat in Palm Desert, California, not far from Palm Springs. If you work in post but aren’t familiar with this event, I would highly recommend attending. Once a year, many of the top technologists working in television and feature films get together to share ideas, creativity and innovations in technology. It is a place where the most highly credited talent come to learn alongside those that are just beginning their career.

This year, a full day was dedicated to “workflow.” As the director of workflow at Sim, an end-to-end service provider for content creators working in film and TV, this was right up my alley. This year, I was honored to be a presenter on the topic of color flow.

Color flow is a term I like to use when describing how color values created on set translate into each department that needs access to them throughout post. In the past, this process had been very standardized, but over the last few years it has become much more complex.

I kicked off the presentation by showing everyone an example of an offline edit playing back through a projector. Each shot had a slight variance in luminance, had color shifts, extended to legal changes, etc. During offline editing, the editor should not be distracted by color shifts like these. It’s also not uncommon to have executives come into the room to see the cut. The last thing you want is the questioning of VFX shots because they are seeing these color anomalies. The shots coming back from the visual effects team will have the original dailies color baked into them and need to blend into the edit.

So why does this offline edit often look this way? The first thing to really hone in on is the number of options now available for color transforms. If you show people who aren’t involved in this process day to day a Log C image, compared to a graded image, they will tell you, “You applied a LUT, no big deal.” But it’s a misconception to think that if you give all of the departments that require access to this color the same LUT, they are going to see the same thing. Unfortunately, that’s not the case!

Traditionally, LUTs consisted of a few different formats, but now camera manufacturers and software developers have started creating their own color formats, each having their own bit depths, ranges and other attributes to further complicate matters. You can no longer simply use the blanket term LUT, because that is often not a clear definition of what is now being used.

What makes this tricky is that each of these formats is only compatible within certain software or hardware. For example, Panasonic has created its own color transform called VLTs. This color file cannot be put into a Red camera or an Arri. Only certain software can read it. Continue down the line through the plethora of other color transform options available and each can only be used by certain software/departments across the post process.

Aside from all of these competing formats, we also have an ease-of-use issue. A great example to highlight on this issue would be a DP coming to me and saying (something I hear often), “I would like to create a set of six LUTs. I will write on the camera report the names of the ones I monitored with on set, and then you can apply it within the dailies process.”

For about 50 percent of the jobs we do, we deliver DPX or EXR frames to the VFX facility, along with the appropriate color files they need. However, we give the other 50 percent the master media, and along with doing their own conversion to DPX, this vendor is now on the hook to find out which of those LUTs the DP used on set, go with which shots. This is a manual process for the majority of jobs using this workflow. For my presentation, I broke down why this is not a realistic request to put on vendors, which often leads to them simply not using the LUTs.

Workarounds
For my presentation, I broke down how to get around this LUT issue by staying within CDL compatibility. I also spoke about how to manage these files in post, while the onset crew uses equivalent LUTs. This led to the discussion of how you should be prepping your color flow at the top of each job, as well as a few case studies on real-world jobs. One of those jobs was a BLG workflow providing secondaries on set that could track through into VFX and to the final colorist, while also giving the final colorist the ability to re-time shots when we needed to do a reprint without the need to re-render new MXFs to be relinked in the Avid.

After a deep dive into competing formats, compatibility, ease of use, and a few case studies, the big take away I wanted to leave the audience with was this:
– Ensure a workflow call happens, ideally covering color flow with your on set DIT or DP, dailies vendor, VFX and DI representative
– Ensure a color flow pipeline test runs before day one of the shoot
– Allow enough time to react to issues
– When you aren’t sure how a certain department will get their color, ask!


Jesse Korosi is director of workflow at Sim.

Review: NewBlueFX’s ColorFast 2 for editors

By Brady Betzel

Basic color correction is rapidly becoming a skill that is expected of an editor, or even an assistant editor. If you have had the luxury of using a colorist and/or an online editor, you have probably seen them use apps such as Blackmagic Resolve, Avid Symphony, FilmLight’s Baselight or other color grading tools. These systems have so many levels of intricacy that without years of experience in color correction, most editors’ knowledge starts at the beginning stage.

If you are an editor looking to do basic color correction, slight secondary correction and, maybe, even a creative grade, you probably want to stay inside of your NLE, whether it’s Adobe Premiere, Apple FCPX, Avid Media Composer, Magix Vegas, or even After Effects. This is where NewBlueFX’s latest color correction and grading plug-in comes into play.

Featuring over 60 different looks (sometimes referred to as creative LUTs or preset color grades), skin tone isolation and the ability to isolate regions of an image for the video scopes to analyze, New Blue ColorFast 2 is a modest color correction app without the overwhelming toolset of a full-fledged color correction application.

The Details
ColorFast 2 costs $99 and works in apps like Vegas Pro 10+, Resolve 11+, Premiere CS6/6.5/CC, After Effects 5+, FCPX, Media Composer/Symphony 6+ and Grass Valley Edius 7 and 8. If you are using apps like Resolve you probably would only use ColorFast 2 for its preset looks since you already have access to all of the color correction tools included in the plug-in — unless you like the region isolating feature for the video scopes, something I find really intriguing.

ColorFast2 RGB Scope and the Lumetri RGB scope.

Most people reading this review will probably want to know why they should buy ColorFast 2 when Premiere Pro has a lot of these features built into their Lumetri color correction tools. To be honest, there are only a few things that ColorFast 2 has that Premiere, or other apps for that matter, don’t have: region-controlled video scopes, skin color isolating and NewBlueFX’s color presets. You should really check out NewBlueFX’s product page for ColorFast 2 to see some more examples of the color presets and download a trial for yourself.

Right off the bat, I felt that stacking ColorFast 2 after the Lumetri color correction tools in the effects panel in Premiere is the proper order of operations. If you are familiar with LUTs and how the chain of command works, you probably have experimented with color correcting before and after the LUT is applied.

Typically, a LUT gives the colorist a good starting point to grade from, but these days you may see creative LUTs. If the creative LUT doesn’t quite look right you will want add color correction first in the chain of command and then the LUT. This is how I would work with ColorFast 2 and Lumetri color correction tools. You will be correcting the footage to work with your creative LUT instead of correcting the LUT, which most of the time will give you inadequate results. Long story short: stack your ColorFast 2 effect after Lumetri tools in the effects window and then fine-tune the Basic Correction settings with your ColorFast 2 preset to get a great color grade.

The ColorFast2 waveform with isolated scope region.

Video Scopes
I was excited to check out the video scopes inside of ColorFast 2, so I jumped to the bottom where the Region Scopes twirl-down menu is. Under that is the Video Scopes menu, which contains Vectorscope (Classic), Vectorscope (Color), Vectorscope (Sat, RGB Parade), Waveform and Histogram. The real beauty is that NewBlueFX gives you the ability to isolate a square region of your footage to be output through the video scope. This allows you to pinpoint your correction a little easier, and I really love this feature… but I also noticed that when you have both the Lumetri video scopes, as well as the ColorFast 2 scopes there is a discrepancy in values. I tended to like the Lumetri video scopes a little better. In fact, they go all the way up to 100, where the ColorFast 2 scopes only go up to 80 — this could very well be a bug in the compatibility between ColorFast 2 and the new Adobe Premiere CC 2015.4.

One issue I found with the ColorFast 2 scopes was that I couldn’t move the actual scope around or have more than one on at a time. While the region selection is an awesome feature, being able to see your full image is sometimes more important, so that is why I would probably stick to the NLEs built-in scopes.

Primary, Secondary, Output Correction Menus
Going back to the top of the ColorFast 2 Effect Editor menus, up first is the Primary Correction twirl-down menu. Here you can quickly white-balance your footage with an eyedropper, even keyframe it. In addition, you can adjust the White Strength, White Tweak (fine-tune control of the white color), Hue, Saturation, Exposure, Brightness and Film Gamma. A problem I encountered was that if you do a primary color correct on your image and then choose a color preset, all of your primary work gets reset, which is a real bummer if you want to correct and then grade your footage. So, if you want to work in ColorFast 2 in a more traditional way, where you color correct then color grade, you may want to do it in two separate effects. Moreover, you may want to primary color correct inside of the Lumetri tools then stack the ColorFast 2 on top.

Secondaries menu.

Next up is the Secondary Correction twirl-down menu, which gets you into the real meat and potatoes of the plug-in. There is a helpful “Show Mask” drop down that will allow you to isolate and view Highlights, Midtones, Shadows, Skin Color Mask and a Shape Mask. Inside each of these you can adjust Tint, Saturation, overall Level, and even enable and disable this secondary if you want. Further down in the secondary menu you can adjust the High, Mid and Shadow thresholds (basically transitions from high to mid or mid to shadow), and even the blending and spread.

While still in the secondary twirl-down menu you can jump into the Skin Mask, which will quickly help you identify skin color, soften imperfections and even help keep skin color fidelity while adjusting the rest of your image.

The last menu is the Output Correction twirl-down. Here you can do a widespread correction that lands after the fine-tuning. You can adjust overall Saturation, Exposure and Brightness.

Summing Up
In the end, I think ColorFast 2 is best suited for people who want a quick color grade by applying a preset look but who also want a little ability to fine-tune that look. ColorFast 2 has some pretty good-looking presets like Vintage, Fallout, Gotham and even some black and white presets like B&W Ink. It’s even more fun to go and purposely change your white balance to something crazy, like a deep purple, for interesting grades. You should definitely try NewBlueFX’s ColorFast 2 if you are looking for some additional creative grade looks while still being able to individually tweak the output.

Brady Betzel is an Emmy-nominated online editor at Margarita Mix in Hollywood, working on Life Below Zero and Cutthroat Kitchen. You can email Brady at bradybetzel@gmail.com. Follow him on Twitter @allbetzroff.

BenQ offering 4K UHD monitor for editing pros

For video editors looking for a new monitor, BenQ America has made available the PV3200PT IPS, which is purpose-built for post workflows. The 32-inch 4K Ultra HD display offers color precision via 10-bit, 100 percent sRGB color, which follows the Rec. 709 standard. Available now, the unit sells for $1,499.

The PV3200PT reproduces color tones with a Delta-E value of less than or equal to two and features a 14-bit 3D LUT to display an accurate color mixture for improved RGB color blending. By balancing brightness to a deviation and chromaticity less than 10 percent, the monitor offers a more consistent viewing experience. The monitor also features simple hardware and software calibration by allowing users to adjust the unit’s image processing chip without altering graphics card data.

An OSD controller provides preset custom modes so users can easily switch between Rec. 709, EBU and SMPTE-C modes. The PV3200PT is part of BenQ’s Eye-Care models, which are designed to increase visual comfort while performing common computer tasks. While conventional screens flicker at a rate of 200 times per second, BenQ’s ZeroFlicker technology eliminates flickering at all brightness levels, which reduces eye fatigue and provides a more comfortable viewing experience during prolonged sessions of computer use. Further capabilities include ergonomic customization such as height, tilt, pivot and swivel adjustments.

Watch this space in coming weeks for a review of the product via video editor Brady Betzel.