Nuke - Feature-quality glow workflow tips

#1

Hi all

First post on this great platform.

I’m currently trying to figure out the best workflow for feature-quality glows. Hoping to get some insight from experienced compositors on the topic. The glow in question are the common “burnished” kind of glow usually present in exterior scenes. A good example of what I am referencing is Next Gen, where the highlights have a nice warm glow to them.

Could anyone suggest a potential workflow? Some workflows I already consider are - shuffling out speculation channel and applying blurs, merging plus on top of beauty. Additionally, ensuring blur is exponential. Beyond that, I am wondering if there are any additional or unique merge operations/Cc/Grade etc. too tricks anyone can give to make my scenes look much better. This includes how to properly manage off-camera “flares” - but the kind that falls across the frame, kind of like a ramp of light. I suspect something more involved than basic flare nodes are used.

In particular I am trying to make my glows look feature quality and avoid the usual flat, straight blur results with standard tutorials all over the internet.

Please find a frame from Next Gen below which contains spec glows and soft, diffused lens flaring.

IMG_3211
IMG_3211.JPG1100x618 68.3 KB

Any help would be greatly appreciated.

Thanks

#2

There are a number of ways of tackling this… Usually, I would grab the spec pass (if it’s not available, just pull a luma key and isolate the highlights) and give it a large generous glow. Use an exponential glow to ensure it has a realistic falloff.

Here are some suggested glows/exponential blurs:
http://www.nukepedia.com/gizmos/filter/l_exponblur
http://www.nukepedia.com/gizmos/filter/bm_opticalglow (my personal go-to)
http://www.nukepedia.com/gizmos/filter/apglow

Otherwise, create your own by stacking blurs on top of each other with an exponential falloff in size and mix.

You could grade it (warm it up maybe), then merge it back on top, and perhaps use an “over” instead of plus or screen (aaargh!) so you don’t make your highlights too bright. Then mix it back quite a bit (you’ll often be at something like 0.1 or less). Hope that makes sense!

#3

Hi eugen-olsen

Thank you very much for you concise reply!

I’ve tried out the opticalglow and certainly seems to do the trick. It’s a nice gizmo so can see why it’s your go-to glow node. It also gives that nice “burnished” highlights when the gamma is increased which is exactly what I was after. I appreciate the recommendation!!

While on the point, what are your thoughts on glows existing outside of the camera? In the above image, it appears as though the flare/glare is coming from screen-right too (as though light is entering the lens from a source outside the frame). From your own experiences, what are your thoughts on achieving and controlling such an effect. I’m thinking something simple like a ramp/gradient across the screen. To me, creating a flare node for this is a lot of work for something that may/may not be distinguishable from a simple over-layed (screened?) ramp. But I may be over-simplifying here.

Thanks!

Thanks

#4

These kinds of optical effects can easily be overdone, but used well they can really integrate and improve the ‘sense’ of a shot.
I’ve often used optical flares and tracked (and offset) a point offscreen to produce a flare playing into the shot, and then instead of using the flare itself, I would reveal a lens dirt texture that’s blurred and just slightly visible. Gradients can also work, it just depends on what kind of movement you want.
But only do it if the shot calls for it!