Can FKG3 replace three Cadet Hard Keys?

Here you go:

Parrot MP RGB Still → Mult
Mult → FKG-3’s Foreground input and Cadet Hard Key Generator (HKG) x3’s Key inputs
FKG-3’s RGB out, the 3 + outputs and the 3 - outputs from HKG into two Fox PASS4 (Quad Passive Switches) and then encoded. I’m switching between each set of outputs in different parts of the patch. FKG-3 is set to non-inverted key (middle), Foreground Source and Luma Mode. At 1:13 on 060722-1, I switch it to the inverted key (top) on FKG-3 so you can see that the brightest parts of the image result in those areas moving towards black when Softness is closer to CW.

For modulation, I have a variable 1V offset from DAISY multed through MULTB into the 3 VC inputs of HKG. Another variable offset from DAISY is plugged into FKG-3’s Threshold input. On all modules, the Threshold pot is set CCW and the attenuverters are at CW so they are entirely controlled by the input offsets.

Then I plug PR in LFO mode into DAISY to break the normalization so the offset is replaced by PR. Stuff gets tweaked on PR. While FKG-3 is monitored, I mess with Softness a bit but it starts at CCW, i.e. Hard Key.

Same as above but I switch MP’s RGB outs to 3 ramps out from Visionary Ramps. Pause the video at the start and have a good hard look at where the ramps are positioned from 0-1V for each color.

Now the major difference, different Threshold offsets on the HKGs by manually adjusting each HKG’s pot and then adjusting the offset/VCO into all three HKG’s VC inputs. The Quad Switch is regularly being flipped to show + vs - hard key outputs. First MP RGB still and then Visionary Ramps:

Lars articulates it far better than I could in this thread but let me know if anything isn’t obvious. These were just quick patches I threw together.

On the HKG examples, anytime that you see a primary color switch to a secondary color (Red → Cyan, Green → Magenta, Blue → Yellow), you’re seeing a positive key invert its position relative to the other two channels. In other words, Red NOT Green & Blue turns into Green & Blue (Cyan) NOT Red. Green NOT Red & Blue turns into Red & Blue (Magenta) NOT Green. Blue NOT Red & Green turns into Red & Green (Yellow) NOT Blue. Remember that a hard key generator is putting out logical levels of 0V or 1V roughly per pixel–there is no gradient.

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