Shooting IR VS Post processing

[RiderOnTheStorm]

What are the advantages of shooting with an IR filter vs taking a picture, converting it to black & white and then inverting it?

 

[Alpha]

Post processing does not an IR photograph make.

 

[Digital Matt]

As Max said, you can't make an infrared photo in post processing. Infrared is a wavelength of light that your eyes cannot see. Capturing infrared wavelengths to a digital sensor or to film provides an image that your eyes, or normal film/capture can not see. No amount of processing can accurately simulate it, let alone reproduce it.

 

[ksmattfish]

What are the advantages...

It depends on your goal. If you want a strange looking photo, and you are happy with the look you are getting in digital processing, then go for it. If you want a photo that somewhat accurately shows the intensity of IR reflecting off of your subject, you need to use IR photography techniques.

Since IR is completely invisible to the human eye, methods of making it visible have to be considered somewhat of a fake to begin with. In IR photography we are giving IR the characteristics of visible light: the greater the intensity the lighter the tone. But that's somewhat arbitrary as tone is a visual description and IR is not visible. Someone could make a camera or film that does the opposite: the greater the intensity of IR, the darker the tone. Or they could make it so different intensities of IR create different hues or saturation.

 

[rmh159]

I've never seen an image that acheived the IR look by post-processing. They look close but anyone who knows the difference can spot the fake pretty easily. In my opinion, it's kind of corny too. I'm all about post-processing to avoid spending money on filters but only if you can't see the difference.

The process you mentioned is kind of like taking a Honda and sticking a Mercedes Benz emblem on it. Anyone with a brain will spot the difference.

 

[ksmattfish]

The process you mentioned is kind of like taking a Honda and sticking a Mercedes Benz emblem on it. Anyone with a brain will spot the difference.

Only if you are trying to sell the Honda as a Mercedes. If the important thing is to drive to the grocery store and get groceries does it really matter what emblem is on the car?

IR film was created for scientific study, and I can understand why scientists might need accurate recordings of IR levels, but most photographers are just using it to get a weird visual effect. If you are posting photos in an IR photo only group, sure it probably should be "real" IR. But if the photog just wants something strange, then there are no limits.

 

[PatriK-b]

Am I wrong if I say that there is an IR filter in front of the sensor?
Does it have to be removed to get real IR picture?

2 questions from a complete newbi on IR shoots.

 

[rmh159]

Only if you are trying to sell the Honda as a Mercedes. If the important thing is to drive to the grocery store and get groceries does it really matter what emblem is on the car?

LOL way to stretch an analogy. I guess it depends on who's going to see you driving the car and how much you care what they think of you.

Like I said, I'm all about ditching filters if they can be reproduced in post... IMO you can't reproduce IR shots in post to a high enough quality level to toss the filter.

Spend the $40 and do it right.

Am I wrong if I say that there is an IR filter in front of the sensor?
Does it have to be removed to get real IR picture?

You're right there's a low-pass filter over the sensor but for the most part it won't block 100% of the IR light. You can get the shot by using long exposures and an IR filter (Hoya R72 is a good example) that will block the visible light.

 

[avcabob]

Does it have to be removed to get real IR picture?

You can also have the filter removed essentially converting the camera to an IR camera to cut down on the long shutter speeds, but I don't think it will really take "normal" picture very well anymore.

 

[ann]

converting a camera for IR work will not allow for normal images to be made.

it is very expensive to do this and so most of us who do IR work with digital cameras use the old fashion method of using a filter.

you will need to convert the file to black and white as it is going to be magenta, but that is not the same as a plug in to make something "look like IR", as most have suggested, it isn't the same, not even close IMHO.
it is worth the extra "work" to do it right in camera.

 

[Alpha]

Since IR is completely invisible to the human eye, methods of making it visible have to be considered somewhat of a fake to begin with.

Strictly speaking, the IR portion of the EM spectrum is outside the visible portion. As such, you can't see it. However, if you've ever peered into a spectrophotometer at long wavelengths, or simply looked through a "black" IR filter, it is still possible to see, though it is very limited. Red & red/black filters do not limit sensor or film exposure to the IR portion of the spectrum.

 

[fightheheathens]

inverting a black and white image will simply give you a negative...
it would look like the equivalent film negative of that same image, which is not IR at all.