I need help with Infrared

[Valadilene]

Okay, so I do not have a converted digital SLR, I have a Hoya r72 infrared filter, which most people seem to get good use out of to produce those really cool looking color- infrared images.. where all the foliage is white and whatnot... but I cant get it to work.

Ive set my custom white balance on a white card.. I've set it off of green grass in sunlight.. I've done camera auto white balance.. all with the IR filter ON..and nothing will work to give me white foliage.. no matter what kind of post-processing i do (channel mixing, auto level, ect)

What in the world am I doing wrong???

shooting on a canon 40D

[Imagebuffet]

In my experience, the white foliage is inevitable. I don't know how you could not get white foliage if you did not want it.

Do you have an example of what you are getting?

[Imagebuffet]

Here is an image that I shot with an IR-modified Canon XTi. I did some sharpening and adjusted the lighting, but this is about how the image looks, straight out of the camera:




Here, I converted the image to black-and-white using Adobe Photoshop Elements 5:




Here, I used APE5 to adjust the colors to the gray of the sidewalk:



Color in an infrared photo is arbitrary, because the human eye cannot see infrared. Some of the color is due to the image sensor picking up some light bleed through its color filters, but most of the color is due to the editor setting up colors. An infrared photo to a human should be just shades of gray.

[Valadilene]

Image- the colors are wonky, I know, but its still possibly to get really awesome looking color infrared photos... i see alot of people doing it where there is no longe ra red tinge to it. I dont have any examples right now, since im at work..but ill post it later. I either get the super red tinge but with dark foliage, not white, or if I set my white balance off of grass or a green bush the entire pic has a green tinge and the plants are super saturated green.. the same plants I set the WHITE balance on.. ill post examples this evening

[Valadilene]

okay so i lied, i do have one of the images with me. This is edited a bit in photoshop, but not very much at all.. it did not come out of camera with a red tinge at all.. this is an example of setting the white balance on a green leaf in the sunlight (from the plant in the foreground) with the IR filter on.. look what it did to the plants.. I just dont get it.

[Imagebuffet]

I've looked around the Web a bit and I've played with your photo in Adobe Elements. I'm wondering where you got your Hoya R72 filter? It is possible that your camera is interpreting some of the IR light as if it were visible light. This could be due to the pixels under the color filter picking up IR light, and deciding it is "green." But, I'm beginning to think that your camera is showing the leaves as green because it actually is picking up visible, green light.

What you can try is taking photographs of foliage under bright, incandescent light (either electrical or solar). Your photo has a cloudy sky; that should not matter, but I note that the blue parts of the sky should be very dark (black or red, but dark), and the clouds should be very bright, as should be the foliage. Your photo looks like it was produced by a dark red filter, but not an IR filter.

[Valadilene]

Got the filter at a local camera store, reputable one. do you think it could be caused by stacking it with my UV filter? maybe light leak between the two filters?

when I set auto WB the photo is very RED, but still no white foliage..

[Imagebuffet]

I'm wondering if this is something pecular to the 40D? In my reading, I found that out of the Canon 20D, 5D and XTi, only the 40D is able to display the light from an IR remote without any modification of its filter. It may be that Canon is using a different process to take out the IR and keep visible light in an image, perhaps a different mask or filter or light path. If so, your IR filter might not work as expected.

Perhaps you could try your filter on a different camera, and a different filter on your 40D? See what happens. I really cannot come up with a good explanation for your results. I don't know how I could get your results if I wanted to.

[Valadilene]

ill do some research, maybe steal my friends nikon and see if it works on hers. thanks

[Bob_S]

After reading this thread, I played around with my R72 that I just got last week for my G9. From what I saw, you need to have the direct sunlight on your subject (I'm guessing so the IR light is reflected off of it). If I shot plants with the sun shining directly on them I got the white effect. When they were in shadow or if the sun was in front of me, they were dark.

I played around with WB too and found that using a custom WB on the sidwalk or a cloud lost the red tint.

I shot it in Av mode wide open at ISO 200 and was almost able to hand hold it.

Not sure if that will help, but it could be something else to try.

[Imagebuffet]

Originally Posted by Bob_S

After reading this thread, I played around with my R72 that I just got last week for my G9. From what I saw, you need to have the direct sunlight on your subject (I'm guessing so the IR light is reflected off of it). If I shot plants with the sun shining directly on them I got the white effect. When they were in shadow or if the sun was in front of me, they were dark.

The problem isn't whether the foliage is light or dark. The problem is that his foliage is green. It shouldn't be green in IR.

I'm not trying to be snide when I say this, but, I would expect things in shadow to be darker than things in direct light. That's what you are observing with the plants in sunlight or shade.

[Bob_S]

Originally Posted by Imagebuffet

The problem isn't whether the foliage is light or dark. The problem is that his foliage is green. It shouldn't be green in IR.

I'm not trying to be snide when I say this, but, I would expect things in shadow to be darker than things in direct light. That's what you are observing with the plants in sunlight or shade.

True, but if it is not directly reflecting the IR light then I think there is more opportunity for the color to come through.