I've been experimenting with new combinations. It is designed to counter the difficulty I had to adapt the "blue trees" technique popularized by Christoph. This is a straight out of camera technique in which the colors of the real world are represented normally along with the infrared displayed as blue, like a 4th primary.

The main difficulty I encountered with the blue trees technique is the conflict that happen between the blue IR and the yellow-greens of the vegetation. In additive color synthesis blue and yellow cancel each other. This leads to a desaturation of bright foliage hues or an unpleasing color in young and healthy plants. 

The idea here is to use the XB30 to cut out all yellow light reflected from plants, allowing only pure green to reach the sensor. Pure green and blue IR should mix together nicely as saturated cyan and turquoise.

I tried different combos. I'll post a few photos from each

The DB940 Combo

• Hoya Sepia B, warming filter, on the lens

• Omega XB30, saturation filter, behind the lens

• Midopt DB940, IR reduction filter, behind the lens

The super DB840 combo

This second stack has a better balance between IR and visible. It passes a little bit more visible.

• Hoya Sepia B

• Omega XB30

• Midopt DB850

• Midopt DB830

I tried it in an urban environement first :

then by the sea :

The unknown combo

There is a third combo that had the XB30 in it but I can't find which filters where used exactly.

The blue setting sun combo

The cool light of the sky provides visible light illumination and the warm rays of the sunset color the trees with infrared.

• Omega XB30

• DB830

• GRB3

• Hoya Sepia B

Two simpler combos, without the XB30

It worked perfectly fine, at least in overcast weather.

• DB830

• GRB3

• Sepia B

This one can also work however I remember it being non-consistent. It works on a cloudy day but in direct sunlight the greens and yellows would start cancelling the blues.

• DB940

• Sepia B