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Published: 2007-11-29 21:17:03 +0000 UTC; Views: 949; Favourites: 58; Downloads: 23
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One made of glass...
People doesn't understand that it's not about the filter, 99% of times it's a Hoya r72, like this, the key is the customized white balance...
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And how do you get the white balance just right?
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Simply trial and error, thereΒ΄s no magical recipe
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not according to most, they make it out to be some sacred art.
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^_^ (there are idiots everywhere xD)
Do you know something about alchemy? when you reach something in a manner you can't understand nor explain, tends to be a highly protected secret, something between sacred and mystical... same with ir photography.
Are you interested in the whole process? from inner to outer: the camera, as you may know, every digital camera has a built-in ir cut filter, to avoid overexposition (ir converted cameras has changed this filter with a r72), the most modern camera, the less sensitive the sensor is. The one above was taken with the D50, which has the same ccd as the D70/D70s, the first reflex used on ir photo. Nowadays my main camera is a D300, much less sensitive to near infrared, but still ir capable, is likely newer cameras will wear a stronger cut-off filter and even less sensitive.
Next stop, the lens, inner coated layers may change colour rendition, let me explain it with samples:
[link] This one was taken with a nikkor 18-55 using auto white balance and the r72 filter
[link] This one using a sigma 28-200 with auto wb too
Note on post processing: the original image as came from the camera tends to be really bloody, so sometimes a blue and red channel swap is needed, the first one has both channels swaped, the second one don't, why, see by yourself [link] the blue parts are recovered but the pink points... o_O The same camera, the same parameters, the same filter, the only difference are the lenses...
As you may know, most of modern cameras allow to create a custom white balance, you shoot something white and she learns the curve, if you shoot something white with the ir filter placed on... easy uh? Mistake, with the filter placed everything green, mostly vegetation, looks white, so, why people creates their wb preset the wrong way? who knows.
The difference? well, judge by yourself [link] using the nikkor 18-55 [link] with the sigma, much better but without channel swapping for obvious reason 
And finally the filter itself, the number at the label says the lenghtwave transsmisivity (not sure if it's written this way, english is not my main languaje xD), the higher the number, the more restrictive it is, that reduces the false colour and makes expositions much longer.
It's easy to see that ir photography has only few differences with the conventional one, light reflected by objects captured by a film/sensor, only changes that you use part instead of the full spectrum, what I can't explain to you is why people who seem to understand what photography is (in general), can look at infrared as a sacred or strange mystical science, since I have no answer for it yet (and my first ir experiments are dated six years ago...)
By the way, nice dragonfly shots but slightly overexposed, try central point light metering or -0.3 exposure compensation
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Alright everything made sense besides 2 aspects, "As you may know, most of modern cameras allow to create a custom white balance, you shoot something white and she learns the curve, if you shoot something white with the ir filter placed on... easy uh? Mistake, with the filter placed everything green, mostly vegetation, looks white, so, why people creates their wb preset the wrong way? who knows."
and what is central point light metering?
Thanks, so much
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[link] Also known as spot metering ^_^
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So, you pick a colour that the majority of other colours have in them. That's pretty much what i believe they are saying
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Not exactly, you pick a reference point. You must think about colours from their essence, energy with a given wavelenght, each visible color comes from a value, with the custom wb you search the starting point to calculate where should be the others, since they has no fixed place to be.
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gotcha, alright then
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q lindooo lugarrrr!!! esos colores parecen sacado de algun cuento magico
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Es que el efecto del filtro infrarrojo, cuanta mas vegetacion, mejor, y otra cosa no, pero bosques por aqui tenemos pa repartir xD
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definitivo, tengo q ir a EspaΓ±a urgentemente!!
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jajajajaja,, pues dile a la lluvia q pase un ratito por acΓ‘, q hace falta y yo con gusto le digo al super Sol q haga lo mismo por allΓ‘!
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Tonses traete algo de sol, que llueve mas de lo que nos gustaria (a ver si te vas a pensar que tanto verde sale de los arboles... anda, ahora que lo pienso... xDDD
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abusadooooooorrrrrrrrrrrr QUE MARAVILLA!!!!!!!!!!!!
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Si tampoco es para tanto, pasaba por alli y...
El caso es que con la cantidad de luz que recibe el sensor de tu camara, lo mismo podias aprovechar esta trenica pa retratos de almas digo de los tuyos
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UmmmmMMmm hehehe pero tendrΓa que dejar a la persona que retrate quieta no? para que se le viera, una exposiciΓ³n larga, sΓ? pregunto... tendrΓ© que leer del tema en cuestiΓ³n
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No tanto como crees, hace poco estuve experimentando, y con el 50mm a F 1.8 e iso 1600 se podian hacer fotos sin tripode con el filtro puesto a velocidades aceptables, como tu sensor es mas grande, compensaria que no tengas objetivos tan rapidos y podrias hacer cosas decentes, a lo sumo una exposicion de un segundo o dos, que tampoco es mucho pedir ^_^
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jajaja, iba a decirte "anda si ya os ha nevao"...entonces he visto las hojas de los arboles....
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A ti si que te ha nevao un glaciar en el cogote... digoooo como va a nevar en octubre xDDD
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