White specks after Chroma Key Studio

I can’t get rid of some white specks after using Chroma Key Studio. Any ideas on what I am doing wrong or what I can do?





Hi there,

Well I probably would have used BCC Primatte Studio instead of BCC Chroma Key Studio for the key but in lieu of that, you can try refining the key using the tools in BCC Chroma Key Studio. But again, BCC Primatte Studio would be better suited for this type of work.

If this is the full rez shot that you are working with then I can pull a key from this source and send you a preset that you can compare against the key that you have. Is the shot static or a frame from a clip? If the latter then please send me the full rez clip and I’ll work with that. You’ll then be able to use the settings that I provide to see the difference and know how to improve your key next time you have a shot like this.

Cheers,
Peter.

Ok, so I downloaded the foreground image and generated a key setup using both BCC Chroma Key Studio and BCC Primatte Studio that you can review. I then saved out the set up for each filter and zipped them - I’ve attached the zip with the setups.

So just copy the zip with these presets, unzip them to the desktop, apply the corresponding BCC filter and load up the preset. Any additional clean up and finishing of the key should be done using the integrated Light Warp and Mocha features.

Cheers,
Peter.

BCC_KeyPresets.zip (4.3 KB)

Dear Mr. McAuley,
THANK YOU so much!
I just got your post, but my day is over (I live in Austria), but will try everything you sent in the morning.
Again, Thank you!
warm regards
jimmy

You are so very welcome, Jimmy. Please let me know if you have any questions regarding this key or other filters in the product - I’m happy to assist in any way that I can.

Cheers,
Peter.

Good morning, Mr. McAuley.
Thank you again. Already improved.
I loaded your presets for both.
I apologize for my ignorance, but do I use both Chroma Key Studio and Primatte? It seems that Primatte Studio does not need Chroma Key Studio. When I enabled both, it seemed to be not as good.
Primatte alone is better, but I still have a little silhouette problem.
When I switched to matte status view, I had a lot of white pixels. I tried to use the rectangle and point methods, but I could not draw a rectangle nor point by point eliminate the white points - no change
When I did clicked auto analyze, it got much worse. The last image below shows the improved, but still with a few points along the outline.



Good Morning Jimmy,

Glad to see that you’re taking the bull by the horns there and working with Primatte to produce a solid key. Although it is possible to combine keys using different tools, for this shot you should only need to use either the BCC Chroma Key Studio OR the BCC Primatte Studio. So here are a few tips that will assist you in pulling a better key result from Primatte :

• always auto-analyze the shot to set a start point for the keying algorythm
• immediately switch to show matte status after using the auto-analyze button
• in matte status, white is 100% opaque, black is 100% transparent and grey is anything that is not either 100% opaque or transparent
• switch to clean up background and use the rectangle tool to push pixels to be transparent
• switch to clean up foreground and again, use the rectangle tool to push pixels to be fully opaque
• you may need to go back and forth a few times with foreground and background cleanup
• use the point tool to reduce spill but be careful with that as you can negatively impact the result with too much spill correction
• use the secondary spill correction - usually, just enabling this removes all spill from the image
• try using the edge cleaner option - it sometimes makes a huge difference in the result and with this shot I think it would help
• use the light wrap edge option to bleed a little of the background onto the edges of the foreground - in light wrap, set the softness and width to 2 and the mix with original to 50%
• and finally, don’t forget about the Mocha mask and tracking integration - you can use Mocha to handle areas that you need to add-to or remove-from the key, such as tracking markers, booms and mics that don’t key out from the scene or reflective surfaces like jewelry that are keying when you won’t want them to.

I hope this helps!

Cheers,
Peter.

Dear Mr McAuIey,
I am having a big problem with auto analyse. When I don’t load your preset, when I start from scratch, I get a very bad result.


hey Jimmy,

Well for this source shot that result is expected. It was the same when I worked with it. As I mentioned previously, you need to work the keyer to get the desired result from this piece. So the first step is to auto-analyze, but you must then switch the view mode to matte status and massage the result. Toggle back and forth between foreground cleanup and background cleanup until you have a clean matte result. Then continue to follow the steps that I outlined above to refine the matte.

Cheers,
Peter.

Dear Mr. McAuley,
Thank you again.
I have used the presets you sent as starting points for all my scenes (they all use the same green screen). I studied what it did. I then go into the mask and point or rectangle out the back- and then the foreground. I worked with the black limit and the choker and have gotten very acceptable.
But I am relieved to know that the initial auto result is expected. Thought my program was screwy.
Again, thanks for all of your help.
jimmy

Dear Mr. McAuley,
Is it better to use after effects for Boris FX or Premiere Pro?
Chroma Key Studio has Pre Key Cleanup which has “push to solid”.
Does Primatte have that?
Can that part of Chroma Key Studio work with Primatte?
Thanks again for all of your help.
jimmy

Hi Jimmy,

Good question! Personally speaking, I find it easier to work in After Effects when creating shot composites but the same results can be achieved via either host.

The Pre Key Cleanup option in Chroma Key Studio is something that we developed as a way to assist with uneven key backgrounds but Primatte does not need this option as you can sample many colors. That said, should you find it useful, you can always stack the two keyers - use Chroma Key Studio for the pre key cleanup push to solid option, then use Primatte to key out the remaining green/blue screen.

Let’s consider for a moment the main differences between Chroma Key Studio and Primatte Studio. Chroma Key Studio is a single color keyer, meaning that you can only pick and key out a single color and it’s tuned to work best on either green or blue screens. Primatte Studio is a 3D keyer, meaning that you can sample more than just a single color for the key making it a much more versatile solution, especially when dealing with uneven backgrounds.

Both Chroma Key Studio and Primatte Studio include garbage mask options to tackle reflections in the foreground or unwanted elements in the background such as boom stands or tracking markers. Chroma Key Studio offers a single simple mask shape for the background and foreground of the key. Primatte Studio includes Mocha with unlimited trackable mask shapes for both the foreground and background.

Primatte Studio also includes the secondary spill corrector which is an incredibly useful one-click option to remove unwanted chroma spill from the foreground. Chroma Key Studio does not have this option.

And Primatte Studio also includes an Edge Cleaner option for refining the edges of the key matte. Again, Chroma Key Studio does not include this option.

I hope this helps.

Cheers,
Peter.

Dear Mr. McAuley,
Once again, I have learned a lot from you. Thanks for the help!
warm regards
jimmy