Any tips for enhancing rainbows?
in [Digital Cameras]
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From: Martin Brown on 1 Jul 2010 03:09 On 30/06/2010 17:24, bugbear wrote: > Ted Nolan <tednolan> wrote: >> I've noticed that whenever I take a picture of a rainbow, it looks >> much less >> impressive than it did to my naked eye. >> >> For instance this one from yesterday is ok: >> >> http://www.tednolan.net/misc/p1120927.jpg >> >> but looked much better in real life. >> >> Any tips for punching rainbows up in GIMP? > > Alternatively, can anyone give an explanation > of why photos of rainbows tend to be disappointing > compared to the Mk1 human eyeball ? > > I've experienced this too. The problem is that the dynamic range of the scene is too high for a camera to handle satisfactorily. It is one place where HDR imaging might help if you have a bracketed set of exposures. Basically the human can distinguish brilliant pure red light as truly pure red whereas the camera sees it as bright first then coloured second (ie pastel shade). Weaknesses in the filter (true also for film) allow enough crosstalk between the colour channels that it desaturates. You can demonstrate this under much more controlled conditions by photographing the various brightly coloured LED indicators on hifi and TVs at varying exposures. > > (some of the corrections in this thread > have been pretty good, BTW) You can get something of the look and feel back by careful use of histogram curves, contrast and brightness. But the eye is just so much better at seeing bright coloured light as truly saturated colour. Regards, Martin Brown
From: Ray Fischer on 1 Jul 2010 03:39 ray <ray(a)zianet.com> wrote: > Ted Nolan <tednolan> wrote: >> I've noticed that whenever I take a picture of a rainbow, it looks much >> less impressive than it did to my naked eye. >> >> For instance this one from yesterday is ok: >> >> http://www.tednolan.net/misc/p1120927.jpg >> >> but looked much better in real life. >> >> Any tips for punching rainbows up in GIMP? >> >> Ted > >Have you tried a polarizing filter? Won't work. Polarizing filters improve sky contrast when the camera is aimed at roughly 90 degrees from the sun. Rainbows always happen opposite the sun. -- Ray Fischer rfischer(a)sonic.net
From: Kevin McMurtrie on 1 Jul 2010 11:41 In article <4c2c4621$0$1581$742ec2ed(a)news.sonic.net>, rfischer(a)sonic.net (Ray Fischer) wrote: > ray <ray(a)zianet.com> wrote: > > Ted Nolan <tednolan> wrote: > > >> I've noticed that whenever I take a picture of a rainbow, it looks much > >> less impressive than it did to my naked eye. > >> > >> For instance this one from yesterday is ok: > >> > >> http://www.tednolan.net/misc/p1120927.jpg > >> > >> but looked much better in real life. > >> > >> Any tips for punching rainbows up in GIMP? > >> > >> Ted > > > >Have you tried a polarizing filter? > > Won't work. Polarizing filters improve sky contrast when the camera > is aimed at roughly 90 degrees from the sun. Rainbows always happen > opposite the sun. A rainbow has polarization so a polarization filter does have an influence. Whether or not it helps depends on conditions and how much of the rainbow is in the photo. -- I won't see Google Groups replies because I must filter them as spam
From: Ofnuts on 1 Jul 2010 13:40 On 01/07/2010 17:41, Kevin McMurtrie wrote: > In article<4c2c4621$0$1581$742ec2ed(a)news.sonic.net>, > rfischer(a)sonic.net (Ray Fischer) wrote: > >> ray<ray(a)zianet.com> wrote: >>> Ted Nolan<tednolan> wrote: >> >>>> I've noticed that whenever I take a picture of a rainbow, it looks much >>>> less impressive than it did to my naked eye. >>>> >>>> For instance this one from yesterday is ok: >>>> >>>> http://www.tednolan.net/misc/p1120927.jpg >>>> >>>> but looked much better in real life. >>>> >>>> Any tips for punching rainbows up in GIMP? >>>> >>>> Ted >>> >>> Have you tried a polarizing filter? >> >> Won't work. Polarizing filters improve sky contrast when the camera >> is aimed at roughly 90 degrees from the sun. Rainbows always happen >> opposite the sun. > > A rainbow has polarization so a polarization filter does have an > influence. Whether or not it helps depends on conditions and how much > of the rainbow is in the photo. A PL Filter can only remove light and so is only good against unwanted polarized light. If the rainbow is polarized the PL can only attenuate it, and not accentuate it. -- Bertrand
From: Mike Russell on 1 Jul 2010 14:17
On Thu, 01 Jul 2010 19:40:41 +0200, Ofnuts wrote: > On 01/07/2010 17:41, Kevin McMurtrie wrote: >> In article<4c2c4621$0$1581$742ec2ed(a)news.sonic.net>, >> rfischer(a)sonic.net (Ray Fischer) wrote: >> >>> ray<ray(a)zianet.com> wrote: >>>> Ted Nolan<tednolan> wrote: >>> >>>>> I've noticed that whenever I take a picture of a rainbow, it looks much >>>>> less impressive than it did to my naked eye. >>>>> >>>>> For instance this one from yesterday is ok: >>>>> >>>>> http://www.tednolan.net/misc/p1120927.jpg >>>>> >>>>> but looked much better in real life. >>>>> >>>>> Any tips for punching rainbows up in GIMP? >>>>> >>>>> Ted >>>> >>>> Have you tried a polarizing filter? >>> >>> Won't work. Polarizing filters improve sky contrast when the camera >>> is aimed at roughly 90 degrees from the sun. Rainbows always happen >>> opposite the sun. >> >> A rainbow has polarization so a polarization filter does have an >> influence. Whether or not it helps depends on conditions and how much >> of the rainbow is in the photo. > > A PL Filter can only remove light and so is only good against unwanted > polarized light. If the rainbow is polarized the PL can only attenuate > it, and not accentuate it. Digital math will get the job done. Use a tripod. Take two images, one with the rainbow attenuated, and subtract the images to emphasize the rainbow. -- Mike Russell - http://www.curvemeister.com |