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04/15/2011 02:11:37 PM · #1 |
Hi, I'm hoping someone can help me with this.
I've recently started exploring the world of Infrared photography.
I use a Canon 7D and recently purchased a B+W 092 IR 20 - 40x filter.
The problem I'm having is that I'm not getting the effect I've been hoping for. Instead of the bright foliage and dark skies, I'm getting dark foliage and normal skies but a deep red tint in the image. I've experimented with everything, high iso, long exposures, different WB settings. I've also experimented in different light settings, harsh sunlight, overcast days, all with the same result, dark plants!!
Has anyone tried IR photography on a 7D? What am I doing wrong here? Did I buy the wrong filter?
I even tried placing the filter infront of my iPhone camera and got better results than my 7D!
If anyone can help on this i'd be forever thankful. I've been trying to search online for any feedback on 7D + IR but cant seem to find any solid answers.
I know it CAN be done with an unmodded 7D because i've seen plenty of images online
here are some samples
7D
iPhone
you can clearly see that the Iphone is giving the proper result while the 7D isn't.
IR gurus please help! |
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04/15/2011 02:18:01 PM · #2 |
| The difference between your iPhone and your 7D is probably the filter covering your sensor. Recent cameras have filters which let practically no IR frequency through, so effectively you just see the red light which the filter you bought lets through. If you have an old DSLR, you might want to try that. Otherwise there are companies who will convert a camera for IR. |
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04/15/2011 02:33:55 PM · #3 |
A red tint "false color" on everything is pretty normal for IR photography. Have a look around for processing an IR image in photoshop.
Usually you need to switch your red and blue channels. Create a new adjustment layer in Photoshop and select Channel Mixer. In the channel mixer, Select "Red" and set Red to 0% and Blue to 100%. Then select "Blue" and set Blue to 0% and Red 100%. This should remove the red tint, and get you close to that typical IR image.
After that, play around with the the Levels and Curve settings to get the picture as you want.
EDIT. You may also need to custom WB on some foliage with the IR filter in place.
Message edited by author 2011-04-15 15:13:36. |
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04/15/2011 02:52:39 PM · #4 |
Yes Garry is right. Firstly set a custom WB by using a shot of some foliage (for example) and use that as your custom WB.
Then the most common image syou see of white foliage and deep blue skies is done using post processing. There is a good tutorial here on DPC that explains it very well.
Message edited by author 2011-04-15 14:54:45. |
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04/15/2011 04:20:24 PM · #5 |
The previous two posts are correct. For white balance, take a picture of a nicce green lawn to set the white balance. (Doesn't need to be in good focus, just not any other colors to any sizeable amount in the image.
Use levels to get the maximum distribution of tonal range. You will find, before adjustment, that the bottom end is set too low, and the high end is usually set higher than the brightest information in the image.
Infra red with no color adjustments
Infra red blue and red channels swapped
Infra red levels adjusted and converted to B&W
For an unconverted camera, expect long exposure times as little infra red makes it through. Long exposure times means from 30 seconds to a couple of minutes. (Depending on the camera) An IR converted camera can get you back down to normal exposure times, which makes life much easier. |
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04/15/2011 05:01:04 PM · #6 |
Thanks for all the feedback guys..
I have seen the tutorials online on swapping red and blue in channel mixer but it seems the problem is with my original image. I have not yet tried setting a custom white balance on green foliage. In fact i'm not even sure how to do that I have to research setting custom white balance on my camera.
But shouldn't I be able to set a custom white balance in RAW conversion? Or does it make a difference if I do it in camera?
I will try again tomorrow with some longer exposures and under some sunlight.
I will not give up on this till I get it right!
Also going to try this on my old 400D and see how it works... |
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04/15/2011 05:16:30 PM · #7 |
| You can set a custom white in post processing, it is just much easier to do in the camera. |
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04/15/2011 06:29:09 PM · #8 |
I haven't used my IR filter since one of my early point and shoot cameras but have been wanting to try again, so I'm interested to see what results you can get as you have the same cameras as I do. I really hope you can get it to work with the 7D because I'm not keen on doing IR using the 400D due to lack of live-view.
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04/15/2011 07:30:53 PM · #9 |
| I'm still waiting for a Hoya R72 to become available on Ebay for less than $80. |
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04/15/2011 08:01:33 PM · #10 |
Originally posted by Timosaby:
Thanks for all the feedback guys..
I have seen the tutorials online on swapping red and blue in channel mixer but it seems the problem is with my original image. I have not yet tried setting a custom white balance on green foliage. In fact i'm not even sure how to do that I have to research setting custom white balance on my camera.
But shouldn't I be able to set a custom white balance in RAW conversion? Or does it make a difference if I do it in camera? |
If your software has a White Balance picker, that's probably the easiest. One problem that I have is that Lightroom only goes down to 2000K WB, and it would be nice to be able to go lower.
Originally posted by Timosaby:
I will try again tomorrow with some longer exposures and under some sunlight. |
I've found that making much longer exposures than the meter suggests makes all the difference. My camera has a fairly weak IR cut filter, and 2-8 seconds in full sunlight is right in my camera's sweet spot. You are basically only recording red light, so more exposure is always good to reduce noise.
Originally posted by Timosaby:
I will not give up on this till I get it right!
Also going to try this on my old 400D and see how it works... |
One interesting thing is that flashes put out near-IR light as well as visible light, so you can do IR with flash if you are inclined. Weegee is famous for shooting IR and using an IR only flash to shoot teens in dark theaters in the '50s.
Message edited by author 2011-04-15 20:02:25. |
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04/16/2011 05:19:50 AM · #11 |
| Whilst the posts about setting the colors right are certainly very good advice, I still think that you have not enough IR light hitting the sensor with your 7D. Just white balance will not help if you have little details in the light tones. Except for the really skilled post-processers. Please tell me if I am wrong, but could you not get very similar "IR" effects by post processing a picture with a red filter in front of your 7D? |
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04/16/2011 10:49:04 AM · #12 |
Originally posted by MistyMucky:
Please tell me if I am wrong, but could you not get very similar "IR" effects by post processing a picture with a red filter in front of your 7D? |
It may be similar, until you get the WB sorted out. Foliage in IR goes white. With a red filter, you are just getting dark red foliage. There are some things that reflect IR differently than visible light, and the effect is difficult to duplicate.
It's like a polarizer filter, you can get a decent simulation of the effect with lots of time and energy, or you can use the filter and get the full effect from the get-go. |
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10/01/2014 05:16:00 PM · #13 |
I am just about to send my spare Canon 400d for a 720nm IR conversion. I have spoken to the people who do this and have assured me my camera would be perfect for the conversion. I am a little concerned that Gina isn’t too keen due to lack of live-view on this camera. Does IR need the live view function or is it a personal choice. (I never use the live view) Please can anyone advise, don’t want to throw £260.00 away.
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10/01/2014 05:23:55 PM · #14 |
Originally posted by dbarb:
...Does IR need the live view function or is it a personal choice. (I never use the live view) Please can anyone advise, don’t want to throw £260.00 away. |
I can't think of any reason that live view would be inherently superior when shooting IR. More a personal preference thing, I believe.
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10/01/2014 05:43:29 PM · #15 |
My reason for referring to live view was because the human eye can't see through an IR filter. I've got no experience of converted cameras, so I don't know if this problem still applies.
For what it's worth I've never had any success shooting IR with my Canon 7D, but have done slightly better using micro four-thirds.
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10/01/2014 05:44:50 PM · #16 |
Originally posted by kirbic:
Originally posted by dbarb:
...Does IR need the live view function or is it a personal choice. (I never use the live view) Please can anyone advise, don’t want to throw £260.00 away. |
I can't think of any reason that live view would be inherently superior when shooting IR. More a personal preference thing, I believe. |
Ahh, but there is!
If you're using filters that block the visible spectrum, (think IR pass) then you will actually NEED to use liveview to compose an image.
This usually comes into play with a full-spectrum conversion, where you need to actually use a blocking filter on the front of the lens, since it's not present on the sensor. (as you would find in a 'normal' IR conversion) |
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10/01/2014 06:37:03 PM · #17 |
Originally posted by Cory:
Originally posted by kirbic:
Originally posted by dbarb:
...Does IR need the live view function or is it a personal choice. (I never use the live view) Please can anyone advise, don’t want to throw £260.00 away. |
I can't think of any reason that live view would be inherently superior when shooting IR. More a personal preference thing, I believe. |
Ahh, but there is!
If you're using filters that block the visible spectrum, (think IR pass) then you will actually NEED to use liveview to compose an image.
This usually comes into play with a full-spectrum conversion, where you need to actually use a blocking filter on the front of the lens, since it's not present on the sensor. (as you would find in a 'normal' IR conversion) |
Right... I should have specified that my comments were in reference specifically to the proposed 720nm conversion, which would not require a front-side filter
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10/01/2014 08:02:33 PM · #18 |
| It seems to me that live view may be helpful for focusing, since you can't see the IR image with your eyes and with most lenses, IR and visible light focus differently through the lens. |
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10/02/2014 02:30:41 PM · #19 |
Many thanks for your feedback,
Think I need a little more thought about the conversion. Don't think I know enough about IR photography to take the plunge. Thank you for making my decision at this moment.
I know very little about IR pass
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10/02/2014 11:13:14 PM · #20 |
If you have your camera converted by a quality outfit, they calibrate the focus to compensate for the IR difference. My 30D appears normal through the viewfinder, and autofocus works great as well. Except for the images, you would never know that you are not using a standard camera.
I can't speak to filters in front of the lens. My unconverted 40D, and 5D II, are so slow because of the existing IR blocking filter, that I have never really tried the live view. It is just so much easier to get the converted camera out. |
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10/03/2014 03:10:46 AM · #21 |
| Many thanks ambaker, Decided now to have it converted. Thank you all for your expertise to make my decision. |
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