Sky Replacement: Test1

After a busy morning in the Tin Shed, I snuck away in the evening to test some footage that Vince shot for me. 

I replaced the sky in this shot with one I rendered from Vue by using Nuke to luma key out the original sky.  Unfortunately I couldn't remember how to animate the clouds in Vue so this image seems a bit flat.  There are also some keying issues- seen by the crawl around the treeline.

However this does give an idea of the techniques that can be used.

I also had a bit of a play with the shadows and colour of the footage, adding a purple tinge to the shadows and pink lighting just for fun.

VFX techniques research

This project is going to include a significant amount of VFX work.  I have been working on identifying what Visual Effects and CG elements will be needed for each shot.

So far we are looking at adding Blood effects, Sky replacements, Set extensions, CG props, and CG buildings.  A number of shots will use the greenscreen and then be composited together later.

With this is mind I have been looking at a few different tutorials online to get an idea of how other people might approach some of these tasks.


This is a Sky replacement tutorial which uses a Channel Key and Garbage matte on a still image to replace the sky.  This technique is fairly basic, and could be adapted for use on filmed footage.






This next tutorial is a Sky replacement which uses geometry with a sky texture applied and a camera track to help integrate the sky into the moving footage.  It isn't a brilliant tutorial but gives a good starting point and some ideas to work with. The first two parts of this tutorial focus on preparing the sky. 




In our project we are going to be compositing skies created in Vue.  I am wondering about the use of camera tracking and how this data could be brought into Vue so we could render out the correct movement.  This clip shows a Nuke/Vue workflow, and it seems that the camera from nuke can be imported into Vue scenes.




Some test footage is being filmed for me at the moment so once I get hold of that I will begin testing out some of these methods.  This should give me an idea of any issues that may crop up that I should be aware of before we begin the shoot.

Visualizing Essimer: Props, Sets and Animatics

Over the past few days we have been hard at work with preparing for the upcoming film shoot.  We began our prop making adventure on Good Friday and still have more to create.

My contributions include a number of odd jobs, the kind that make one feel that they haven't really achieved anything but are important never-the-less.

One thing I do have to show from the past nearly week are a number of masks I have been working on for costuming.

This is a mask for one of the Bone Cultists.   I carved the design (loosely based on Jade's concept art) from polystyrene and then covered it with paper mache.  While I was working on the next lot of masks, Bex did an awesome job painting up the mask.

These other two masks are for the Bounty Hunters.  They have been designed by Jade to contrast with the masks of the Bone Cult.  These masks are were cut from MDF then covered in boiling water to allow the wood to bend.  They aren't quite finished as they need to be backed with black mesh and foam to allow them to fit onto the face nicely.

The major thing I have been working on this week is the 3D Animatic.  The Animatic is an important part of pre-production as it helps to visualize and time out the action of the shots, as well as exposing any continuality issues.  Since time is running short, I arranged for the full VFX team to work with the Previs team to help them get this done.  By making use of assets we already had (such as my character from last years 3D animation) and working on this as a group we were able to get the Animatic done in less than 2 days. 

It's Been a While...

It's been a while since my last post, but a busy time at that.  On the 8th a group of us went location scouting and found some awesome possible locations for our shoot.  Since then we have had a chat about the VFX/ Live action components of the shoot and decided to shoot on location with the actors on the portable greenscreen.  This will be composited into a plate of the location with CG elements integrated. 

Since the storyboards are close to being finished, I will soon be starting on getting the VFX breakdowns sorted out. 

Time is going past so fast now, and we are only going to be getting busier so it's going to be really important that we are well organised going forward.

Vue environments

Today I looked at the concept art for our cinematic, and tried to recreate a similar feel using Vue.  Here are some of the experiments.

Vue Presets

 These two shots the default of two different atmospheres in Vue.

Experiments

I manipulated the sky colour map to make it more pinky/purple.  I also took down the yellow of the sun and the intensity of the lens flare.

These experiments all use a procedural terrain, which I later populated with some plants.  I also added a sea in the later experiments.

 I had difficulty with getting the clouds how I wanted them, but it's just a case of experimenting more when I have the time.

Cloth Simulations

For my Cloth Simulation assignment I did a lot of experiments just changing different attributes of the cloth.  I choose to use my character from The Lonely Mannequin and attempt to simulate a similar style of clothing so that it a direct comparison of both techniques could be easily made.

I found that my experiments got resulted in better simulation to begin with, but that after a certain point any further changes made things worse and worse.

For my final render I reverted the settings to an earlier test- but had issues with the cloth behaving differently in the cache not matching the then it did when using a playblast.

This is the final clip- the simulation would have benefited from some further experimentation to fix the problems with the skirt.

Pipeline Update

I have continued working on the pipeline for our game cinematic based off the footage I have had access to so far.

At this point there is still an assumption that we will be shooting on the F55.  From our test footage so far our DOP/ Colourist has indicated a preference for the look of the footage with the following settings.

XAVC 2048x180
Shooting mode: Custom
Main Op: YPbpr
Colourspace: S-Gamut
S-Log 2
White Balance- 5500k

I tested this footage by converting using Adobe Premiere into the following image sequences:

TGA

TIF

DPX

These sequences were then brought into NukeX, and then rendered back out to be brought into Premiere.  This allowed me to compare the original footage to the converted footage through the histograms, scopes and simple eyeballing.

I found that the DPX files were being read strangely in Nuke which was causing an over saturation of colours.  A solution could be seen through changing the read node to the SRBG colourspace.

At this point in the pipeline I found that the next step would be to shoot some actual test footage in this format, and confirm whether Resolve had any issues with any of our file type options.

However I was informed that Nuke had problems handling footage from the F55, so more investigation was needed.

It seemed that there was a loss of information in Nuke and that areas of the footage which were over or under exposed couldn't be pulled back nicely.  At this point it is unclear whether the problem was actually due to Nuke or an issue with the original footage- which was shot using a continuously changing exposure.

The issue seems to be fixed by changing the Read node in Nuke to read the sequences as Raw.  We also now have some better footage to look at which should have a constant exposure, which will hopefully reveal any further issues.

A pipeline will also be tested for HDCam footage- with a final decision to be made once storyboards are completed. 
 
HDCam is not able to shoot at higher frame rates- meaning no slow-motion shots.  It also cannot be taken into Adobe Suite so a completely different pipeline would need to be used.  It seems that our options for converting this footage for use in Nuke are bringing it into Avid and rendering it out or using a proxy.  I personally don't have any knowledge of Avid or using proxies so will need to do some research and get guidance from those who do.
  
 

Thinking about VFX

Now that we are getting a better idea of the script and concept for our cinematic there are a few things that we need to start considering.

One of the first things to consider is what we want to shoot in live action versus what will be done digitally.

This need to be a discussion between our On-Set Director, the Art Director, and myself- the VFX/ CG Supervisor.

It's important to consider our budget, the length of time we have available and our stylistic intentions.  Because we are creating a quite fantastical world we need to think about whether scenes will be better off being shot on location, on small sets which could later be extended, or on a green screen and later composited into a digital environment.

Some issues we might run into logistically include time and money constraints, expertise and a suitable location for sets to be built.

If in some cases a huge amount changes would need to be made to a location in post we might be better off using a green screen, or even a small set in front of a green screen to enable keying.

If we need any large scale action shots we might require an outdoor location for space.  

On a location shoot we might need to using motion tracking to enable CG elements to be integrated.  We would also need to look into sky replacement- the basics of which seem relatively straight forward for a locked off shot according to this tutorial:

      


I also want to experiment in Vue to get an idea of whether this is another possibility for us.