Topic: Chroma Key and Blender CGI Tests

https://farm5.staticflickr.com/4897/44907647115_9b1c937816_z.jpg

Chroma and Effects Test by SteampunkDoc, on Flickr



Yep, another Chroma Key thread... mini/wink

I'm using Vegas Pro 14 and some pretty Dollar Tree posterboard and this was about the best I could get. I've never been one for fancy effects but have finally decided it's time to figure this out. Getting the Enterprise further away from the green to avoid spill and using a handle more easily masked out than my hand are two issues that I'm aware of, but what else would ya'll recommenced?

I added a little backlighting (taking the mask and turning it white, the blurring it and placing it below the layer with the ship) and a lens flare effect just for fun. Opinions?

Re: Chroma Key and Blender CGI Tests

That looks pretty awesome! Keep it up, man!

Re: Chroma Key and Blender CGI Tests

Thought I'd give this a crack myself, having never actually done chroma keying/masking in a vegas before myself. Because of the overspill, a straight-up chroma key will take out some of the color of the rest of the model/make parts of it seem to turn invisible. In gimp, however, it's easy to crop with the selection tool (not the scissors one), and then apply manual color correction. Here was my quick little test:

Top is the gimp version (took me about half an hour to do)

https://i.imgur.com/nP4myO7.png

And the bottom is from Vegas Pro (less than 8 minutes).

https://i.imgur.com/HVT6oOA.jpg

Comparison of mask only:

https://i.imgur.com/94Q6J9H.png

Obviously, gimp takes a lot longer, but gives you more control over the overall effect per frame. Vegas can work well as a quick solution if the amount of green overspill is lessened. I don't really know how to do that... Alter the lighting set up, I guess?

https://i.imgur.com/Z8VtGae.png

Re: Chroma Key and Blender CGI Tests

Dude! That GIMP version looks amazing! mini/jaw
I'm loving the motion streak/blur thing in the first picture, and the masking effects seems flawless.
Fantastic editing my dear sir!

The Vegas attempt also looks nice, but you're right, the green spill in this picture seems to be fatal.
Another side effect I just noticed is that the Vegas Chroma turns her blue-ish (resembling Colombia's slight recolor) rather than the more yellow-ish tint of the NX-01, which GIMP retains. A touch of color-correction can fix that, but it's something else to keep in mind. Thanks for helping me see that!

This was, very much, just a quick test shot. I literally laid the poster board on the floor beneath my ceiling fan light and snapped the picture on my phone. I don't think it'll be hard to manage some better lighting in the future. The model was about 1 1/2 feet from the screen, so moving it further away should help with the spill. I've got two poster boards, and can always grab two more if necessary to make it big enough to get that far away.

While I hate to invest the time to GIMP every frame, my mind goes back reading about all the time consuming effects work Smeagol and Nick Durron put into their early films. If I'm going to attempt this kind of thing, I might as well go all-out and do it right.

Over the next few days I'll try to figure out better lighting, then do a test clip of it actually in motion. Thanks for the feedback!

Re: Chroma Key and Blender CGI Tests

That looks really interesting! I also gave it a try myself but I don't know how to post an image on this site. Can someone help?

Re: Chroma Key and Blender CGI Tests

Ice Fox wrote:

That looks really interesting! I also gave it a try myself but I don't know how to post an image on this site. Can someone help?

You have to use BBCode to post pictures on the forum. First, upload your image to an image sharing site like imgur or flickr. Then, copy and paste the link into your post and put an img tag around it.

For example: [img]urlexample[/img]

Re: Chroma Key and Blender CGI Tests

Willow Tree wrote:
Ice Fox wrote:

That looks really interesting! I also gave it a try myself but I don't know how to post an image on this site. Can someone help?

You have to use BBCode to post pictures on the forum. First, upload your image to an image sharing site like imgur or flickr. Then, copy and paste the link into your post and put an img tag around it.

For example: [img]urlexample[/img]

Thanks for the help. I hope this works:

https://image.ibb.co/iSxkc0/Enterprise0000.jpg

Well I gave it a try using the free version of Blackmagic Fusion. Took about twenty minutes to complete. The keying worked fine but required some masking here and there. I decided to give the ship a rim light at the back to better integrate it with the lensflare. I've also done some color correction and added a glow to the lights of the ship as well as a little zoom blur to give it a sense of speed.

Mod Edit: Updated image link to direct .jpg link, rather than indirect image page, that was linked previously.

Last edited by Dyland (November 14, 2018 (12:31pm))

Re: Chroma Key and Blender CGI Tests

Wow! Ya'll are having a lot more success than I am!

Adding lights to the lights on the ship was a great idea, although the rim light may be turned up a bit much.

I filmed a few shots of the NX-01 in motion last night, but the vain attempts at chroma in Vegas continue to completely fail and once again I didn't get far enough away to eliminate the green reflections on the model. The first one isn't masked, the second is. However, neither seems to be working. Saturday afternoon may open up enough to try GIMPing something, we'll see.

I'm also considering trying my hand at doing the effects shots in Blender instead, but know virtually nothing about how to work that software, so that may not go anywhere.

https://farm5.staticflickr.com/4872/32036059378_24c654aa82_z.jpg

Re: Chroma Key and Blender CGI Tests

Double Post! mini/shifty
Finished the CG test: https://youtu.be/t7pZyn2uVVQ

Gotta say, even if it took ~7 hours to render just that, it's pretty amazing.
Found some tips to help reduce render time, so armed with those, I may pursue this route rather than trying to green-screen a real model.

Stay tuned for more.

Re: Chroma Key and Blender CGI Tests

On your youtube test, it says 'Choma keyed in Vegas', why are you chroma keying if it is a CG render straight out of blender? Surely you have an alpha channel already baked in?

Re: Chroma Key and Blender CGI Tests

That, sir, is because I'm an idiot. 

Or I simply didn't think of it.

My end goal now is to do it all CG rather than doing any green screen. It's proving more fun, looking better, and allows much greater freedom and ease of integrating other elements in the scene. It's now just a matter of fully figuring Blender out.

At the time of that render, I wasn't sure how to change backgrounds in Blender, so it came out with the default gray-ish mess. Which was fine for that simple test. But wanting to just take a peak at that clip with stars, I noticed that the gray was all the same shade while getting ready to export it in Vegas, so plopping a star background behind it using Chroma Key was the work of only a few seconds. That was never going to be my final solution or workflow, it was just so I could see that render with stars.

Progress is slow, but steady. I'm very inexperienced with Blender, so it's taking time to look up/figure out how to accomplish even the most simple of tasks.

Here's the latest video test.

And since then, I've been working on adding a planet: (That still needs an atmosphere.)
https://farm5.staticflickr.com/4913/32114246598_f9a59476b0_z.jpg

Re: Chroma Key and Blender CGI Tests

Wow, those bricks look really realistic! mini/smile Keep up the great work.

https://i.imgur.com/Z8VtGae.png

Re: Chroma Key and Blender CGI Tests

Welcome to the CGI side, Pritchard.

https://i.imgur.com/4b9NnS3.pnghttps://i.imgur.com/GUIl0qk.pnghttps://i.imgur.com/ox64uld.pnghttps://i.imgur.com/v3iyhE5.png

Re: Chroma Key and Blender CGI Tests

https://farm5.staticflickr.com/4884/31081094187_77511b0721_z.jpg

Finally got the stars figured out. mini/dizzy
Blender has a crazy learning curve, especially the particles, but once you figure it out, it's not too bad.
Thankfully there are a lot of tutorials on Youtube.


Next step: Figuring out what kind of lighting I want.

Re: Chroma Key and Blender CGI Tests

Pritchard Studios wrote:

https://farm5.staticflickr.com/4884/31081094187_77511b0721_z.jpg

Finally got the stars figured out. mini/dizzy
Blender has a crazy learning curve, especially the particles, but once you figure it out, it's not too bad.
Thankfully there are a lot of tutorials on Youtube.


Next step: Figuring out what kind of lighting I want.

Dude sweet model!

Some advise, set your background to clear (render-film-check box the transparent box) That way you don't need to green screen.

Also, set your resolution to 100% instead of 50%, that will help with size.

Next, set your device to GPU Compute, if the option isn't there go to your preferences and find the check box for it. (massively faster than CPU compute)

Re: Chroma Key and Blender CGI Tests

Also, if you have discord I might be able to help more if your interested.

Re: Chroma Key and Blender CGI Tests

Neat render! Just to add something to what The_Director said, you could increase the number of samples to render for each pixel, in order to remove some of that grain(noise) in the image. It'll slow down your computer, depending on how strong it is, but it'll improve the quality.

Re: Chroma Key and Blender CGI Tests

@The_Director, Thanks for the offer of help! I've got some craziness these next few weeks with church and family obligations, but I'll certainly keep that offer for help in mind for when the schedule lightens up.

Rather than green screen the Blender renders, I'm just doing it all in Blender. In the above picture, the background is black, while the stars are particles in the scene. This seems far better than bothering to render, then match the camera motions and try to add stars in Vegas. I did take your advice and set the resolution up. Thankfully, the GPU tip is one that I saw before. You're right, it does help! (Not much, since my laptop isn't built for heavy graphics, but every little bit is nice.)

Raytistic, Right now, I've got the samples sitting at 1,000. It's taking roughly 10 minutes a frame, which is killer when the clip is 140 frames long. I tried with higher samples before, but it was simply far too slow for my liking. The lighting setup has been adjusted since that frame was rendered, things aren't as dark and grainy anymore so 1,000 samples may suffice for now. However, you're right, it would help the quality.

Other than rendering the newest draft of the scene, which can be done at night or while I'm at work, little will be done with this through the holidays. However, it's been a great learning experience. Thank you to all for your tips and encouragement! I'll be sure to post the video whenever it's finally done.

Re: Chroma Key and Blender CGI Tests

Some extra tips.

Have you tried a website called sheep It? They will let you render other people’s projects for points which you can trade back to complete your own projects faster.

Another is to check that your lighting is set to full (this makes for more light bounces but signafacly reduces fireflies, allowing you to reduce samples which will reduce rendering times) and there should be a smoothing option you can try with mixed results.

Good plan with forgoing the green screen. Another idea for you is to use an HDRI map instead of an particle system. If done right it may be better than an particle system, at the cost of control of output.

If your a guy with $$$, get blender guru’s pro lighting add on. It’s expensive but very much worth it.

And finally, a shameless plug!

https://youtu.be/ZcT9lh_B4kY

Re: Chroma Key and Blender CGI Tests

I keep having these second notes lol

I am looking for sci-fi ships, but they cannot be themed like Star Trek or Star Wars (For instance LEGO space classic is fine) And I could use ideas for simple stop motion.

Also if you do do sheep it, I can render your projects for you. I have a GTX 1070. it’s not TI but it gets the job done.