Dr Choong was inspired by his expeditions into Endou Rompin and Bako National Park. In the jungle, he viewed from distance, looked from close-up to appreciate the changing rhythm and mystery of Nature. He probed into the eternal and ephemeral of Nature to apprehend the contrasting yet complementing nature of Ying and Yang. He realized that in nature, the solid rock has to live with the gradual erosion process. Even the long lasting mountains cannot avoid the changes of vegetation due to seasonal variations. Staining process and spray gun techniques were employed to achieve the best visual results. He also used hand-made paper to create quality and beautiful tactile and low relief works.

岩景系列也是从恩道云宾森林及巴果国家公园探险中得來的灵感，在森林中他有机会作 “远距眺瞄，临近关注，贴近自然”。 从窥探自然的恒如与替变，他悟出阴阳相对又互补之道和自然规律：「磬石虽坚固，卻须与风化过程共度时光，山丘万年依旧，卻免不了草木的季节更替」。 这一系列的创作方法，大部分是先在半干的手造紙上渲染，待干后再以手绘及喷染手法营造出最佳视觉效果。从自造纸上可以用喷射营造年轮优美规律，色彩和粗糙肌紋及气氛，去描述大自然的风化和腐蚀的过程。其余的是在画布上以手绘及用喷射完成。

Rockscape 1				Hidden Image 1
1985				1988
Acrylic on handmade paper				Acrylic on canvas
122 x 92 cm				92 x 122 cm
Private Collection				Private Collection
Hidden Image 2				Misty Rockscape
1988				1988
Acrylic on canvas				Acrylic on canvas
122 x 152 cm				122 x 152 cm
Artist Collection				Artist Collection
Rock Mood				Rockscape at Dusk
1990				1990
Acrylic on handmade paper				Acrylic on handmade paper
92 x 122 cm				122 x 122 cm
Artist Collection				Private Collection
Rockscape at Dawn				Rockscape XVIII
1990				1991
Acrylic on canvas				Acrylic on handmade paper
122 x 122 cm				92 x 122 cm
Private Collection				Artist Collection
Rhythmic Flow 91-1				Rhythmic Flow 91-2
1991				1991
Acrylic on canvas				Acrylic on canvas
152 x 122 cm				152 x 122 cm
Artist Collection				Artist Collection
Rhythmic Flow 91-3				Mountscape MK
1991				1992
Acrylic on canvas				Acrylic on handmade paper
152 x 122 cm				56 x 75 cm
Artist Collection				Artist Collection
The Sound of ROCK				Rockscape Mt. Aso I
1992				1992
Acrylic on handmade paper				Acrylic on handmade paper
53 x 72 cm				47 x 58 cm
Artist Collection				Artist Collection
The Sound Cliff III				Rhythm Flow 1992-4
1992				1992
Acrylic on handmade paper				Acrylic on handmade paper
48 x 67 cm				75 x 55 cm
Artist Collection				Artist Collection
Yeh Liu-1				Yeh Liu 1992-2
1992				1992
Acrylic on handmade paper				Acrylic on handmade paper
45 x 60 cm				55 x 73 cm
Artist Collection				Artist Collection
Yeh Liu 1992-3				Yeh Liu 1992-4
1992				1992
Acrylic on handmade paper				Acrylic on handmade paper
55 x 73 cm				55 x 73 cm
Artist Collection				Artist Collection
Bercham at Dawn				Cavescape 91-1
1992				1991
Acrylic on handmade paper				Acrylic on canvas
45 x 60 cm				122  x 152 cm
Artist Collection				Artist Collection