John's Jottings

112. There is green, and then there is green - October 2015

Posted on October 1, 2015 at 5:00 AM

As our new layout progressed, we got round to discussing the scenic treatment and the choice between light, medium and dark green scatter materials.


“There’s more to it than that,” Felicity advised.


“Why, how many shades of green are there?”


“In Ireland there are supposed to be forty,” Graham answered.


”Aren’t there fifty shades of grey?” Adrian asked, tongue-in-cheek.


“But isn’t grass just green?” Peter retorted.


“Go and look,” Felicity advised him. “The leaves at the top a swath of grass receive more light than the lower parts, so they will appear lighter and brighter, sometimes almost white. Close to ground level it may be quite dark. I reckon that there are three or four shades for any plant: direct sun light, slight shade, full shadow and back-lit. And each plant has its own basic green, so for any mixed herbage, there will be dozens of tints of green.


“I just mix blue and yellow,” Paul commented. “Add a touch of grey or white to vary things a bit and the job’s done.”


“Ah, yes,” said Jane. “Did you know that yellow and black also make green, but a different range of greens?”


“Black and yellow?” Paul asked incredulously. “Surely it’ll be a dark yellow?”


“Oh, no,” Jane replied. “Think of it this way. Blue is a sort of dark colour. So is black. So the eye can be fooled into seeing yellow plus a dark colour as a green.” Paul was not convinced.


“Only well-tended grass lawns are uniform in colour, mainly because they have a limited number of species and all cut to the same height,” Felicity continued. “Pasture, rough grassland and woodland contain many different species, each with its own range of colours, some of which aren’t even green. And that’s before you consider the flowers and fruits.”


“And don’t forget the shadows,” Jane reminded her. “In sunlight, they aren’t black.”


“Not black?” was Paul’s incredulous comment. “It stands to reason, shadows are always black.”


“Oh, no,” Felicity replied. “In full sunlight, shadows are illuminated by blue from the rest of the sky, so they appear blue-purple. If there’s some cloud, then this reflects some of the sun’s light and shadows are more greyish.”


“Doesn’t it just go to show,” the chairmen suggested, “that it’s a good idea to have periodic reality checks? Just to make sure that the models we produce have some basis in the real world, and that they’re not replicating what we’ve seen in other models, or how we think we remember the world outside the railway room?” And we all agreed with that.


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