Posts by Ross Mason
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And here is a cracker for those who might want some "image stabilisation".
"Here chook chook chook"
Had a bit of a cackle over it.
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This may be of interest to some:
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Capture: Two Tone, in reply to Ian Dalziel,
pulling your legume…
cup of (homegrown)…
Christmas card?
Peas on EarthBean there. Done that.
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I went hunting for some spectral response info for films and stumbled upon a couple that make interesting reading and hopefully explain things. “Panchromatic” is the term i was looking for. Early film was only sensitive to the blue end of the spectrum. Eventually they progressed into the greens and a wee bit into the red. The reason you can use a red light in the darkroom was the film was not sensitive to red light!!!
This first page has a bit of the stuff I was playing with years ago in the aerial survey work. Now done with satellites a whole lot more with more and more and narrower bands to filter the spectrum into channels. The graph on different spectral response to grass, ground, trees, sea etc shows why colours are what they are. Note the extreme high reflectance in the near infrared of green and growing plants. This was/is useful to pick the health of grass or crops because the near infrared reflectance drops when the crop becomes stressed.
http://www.geog.ucsb.edu/~jeff/115a/lectures/films_and_filters.html
This Agfa page gives some specs on B&W aerial film to demonstrate the different spectral response and their uses.
This guy is trying to emulate Ansell Adams which I think someone here was too.
http://www.johndavies.uk.com/atec.htm
B&W film is nice to use with filters because there is only one layer to get exposed. With colour film and digital cameras the problem is the different layers spill over into adjacent colours. So even though a green filter on a digital camera only lets in green light, because the blue and the red has some sensitivity to green, they too get exposed. As someone alluded to, splitting the image into RGB and eliminating it from the product AND using a filter is useful.
The upshot is, if you want to have a real RGB image with a digital camera then you have to take 3 pictures of the same scene. Use a blue filter and delete the green and red layer, then use a green filter and eliminate the blue and red, then a red filter and eliminate the blue and green. Combining what remains should be a true RGB image. The filters MUST be good cutoffs and let minimal light through outside their band.
Polarising filters a cool for enhancing contrast in sky scenes. The blue light from the sky can be highly polarised in different directions around the sky.
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Legal Beagle: Fact check: Q+A on mayoral…, in reply to matt mccarten,
I dismissed it as wishful thinking but maybe that’s why Palino told Chung to go public with her story and force Brown to resign before the week’s end.
Bloody conspiracy theorist.
But then…..it is not beyond the pale to think that they might!!!!
They needed a lawyer.
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There is a subtle problem with trying to emulate Adams and others work using filters. The spectral response of B&W film is used to enhance the changes. The response of film varies across the visible - and UV and near IR as well. It all depends of what type of film is used. Say for instance, there is a decrease in sensitivity in the red end. Then naturally anything red comes out light on the negative. So if you want to eliminate the blue then stick a no blue filter (which allows red to pass) over the camera and then both the red and the blue is decreased. One from the filter, one from the film response. So the combination of film and filter does the weird things. If I remember correctly the classic is a red filter to darken the skies.??
Digitally, you already have the "data" and you can only cheat. You can't take out "half the red" digitally. That is, the deep red and red get cut evenly, whereas with a filter it can be gradually changed over the red spectrum. By all means use filters with a digtial camera but I suspect there won't be the same effects as B&W film.
The response of B&W film is (or used to be) readily available. We spent considerable time sorting B&W film for our multispectral aerial surveys.
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A South African
of Italian heritage, Mr Wewege moved to New Zealand in 2011
Maybe 'e should go bick to plaeying rogby in Ellis Pok.**
Was last seen driving backwards away from the scene in his 10 reverse gear Italian tank.....Run for you life.
How stereotypical......
(** Headline from Alex Veysey years agoe emmitaeting bad SA accent)
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Note those not disgusted by the above post will be receiving their boarding passes for the B ark shortly in the mail, have a wonderful trip.
The B Ark had the telephone sanitisers. I think the purveyors missed that ark didn’t they?
Simply standing for a community board, unsuccessfully, does not qualify for the the epithet ‘politician’.
Yes it does. A bit less than half of our pollies are on a list – those who don’t put up in an electorate. They don’t “stand” at all.
"Wewege comes across like a lying inconsiderate bastard.
Did someone misspell his name – Loo Sewage?
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Yee Haa Islander: Now there’s two!!!!!
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Travelling with paralympians in an Asian country a few years ago: "You handicaps please come the front, you normal people queue at the back please." Had cripples too at another place. But Europe still uses "handicapped" in a lot of general conversation. Translation problems probably.
And I suppose all those (rope?) "bound wheelies" are right into 50 shades eh.