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Anonymous
IR Filter: bad/fake or user error? 2017-03-28 06:26:37 Post No.
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IR Filter: bad/fake or user error? 2017-03-28 06:26:37 Post No.
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Bought a cheap Hoya R72 filter second hand.
I have no experience processing IR whatsoever but I followed exactly what most tutorials tell you to do and I get some (what I think are) strange results.
In upper pic related you see the blues look completely unaffected by the IR filter.
In the lower pic (in which I slightly increased saturation to make it more obvious) you can see that the fence has the same tint as the foliage, along with some of the rooftops, windows, etc. In all IR pictures I could find there's a clear difference between buildings and foliage.
I have some reasons to suspect the filter might be a counterfeit Hoya. The line of the 'H' doesn't cross the 'O' and the label with the serial number on the back of the box doesn't have a code for the type of filter, which some say indicates a fake.
The glass looks very dark as it should, when I look through it at something brightly lit I can faintly see it.
So: am I bad at processing, are my expectations of a 720nm IR filter wrong or is something actually wrong with the filter?
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that image looks dope as fuck. why are you complaining you fag?
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>>3047654
don't post images from your window with recognisable elementa anon, never a good idea on 4chan.
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>>3047658
these are legit
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>>3047654
You need to do a full ir conversion for the intense effect.
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>>3047671
this isn't /b/ faggot, no one here is going out of their way to locate some random anon who hasn't provoked anything, the only people anyone here is going to try and find info on is cancerous tripcunts such as yourself
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>>3047654
IR shots SOOC look like red only. The usual white/color parts are coming from a palette swap, similar to sliding the color information to the IR range. 720nm filters retain parts of the normal colors so it is more "colorful", not a more uniform spectrum like something above 1000nm
It is totally legit, don't worry about it. You can tell the way the color swap is made if you develop from RAW in PS.
Also, note this is not real IR photography, actual IR range is much longer wavelength in the hundred um range instead of nm. This is NIR or Near IR range so it will not behave the same as heat photons would (most basic stuff on IR is about heat photons if you would look on wikipedia or similar) so look up specific areas of NIR if you want to know more.
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>>3047654
I have genuine Hoya R72's and it's normal to see through them when looking at bright objects. You can see quite a bit if you put the filter very close to the eye and put your fingers around it to block any light from going around it. After a while your eye gets used to it and wew, you're seeing NIR. The human eye isn't strictly limited to "visible" wavelengths, just that its sensitivity in the NIR range is so poor that normally visible light overwhelms it.
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>>3048038
R72 is part visible you dingus, H-alpha is still part of the visible spectrum at 650nm and the filter doesn't cut right at 720nm. It is letting through 680nm easily and is more of a deep red filter than a "proper" IR filter.
You can try the same you described on a 780nm filter and you won't see shit. The human eye is sensitive for the visible light, that is why it is called visible range. NIR is still out of our sensitivity.
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