# IR HDR?



## zombiemann (Aug 18, 2012)

I've been playing around with IR photography lately.  It can be a bit.... tricky trying to get the exposure right.  As such I've taken to shooting 3 bracketed shots to give myself a better chance of capturing the right exposure.  With the IR filter on the camera the built in metering is worthless, so is autofocus.  And while I understand the fundamentals of exposure/aperture/ISO/etc even an educated guess is still a guess.  I did some IR work today and got the bright idea to try stacking one of my brackets.  I went through and made sure I had a consistent white balance, swapped my red and blue channels as usual when processing IR shots (gives it a blue sky and makes it look less like a film negative).  I then fed them through photomatix. The first image is the "neutral" exposure of the stack "as shot" with no white balance or anything other than convert to jpg and resize.  The second image is stacked and tone mapped to B&W. The third is a color tone map that I think works well for this pic.  Keep in mind, this is not shot in visible light, so the fact that it looks "weird" is part of the goal.


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## Bynx (Aug 18, 2012)

There is some strange stuff going on where details are gone replaced by a solid gray -- across the road into the bushes. You cant mean that was your goal?


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## zombiemann (Aug 18, 2012)

no, that wasn't my goal.  It's not actually a road but a mowed grass path, my best guess that is a "ghost" like effect of extended exposures with the breeze ruffling the grass.  Sort of like when you take a long exposure of the surface of moving water.  Other than that part though, what do you think of the over all effect?


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## unpopular (Aug 18, 2012)

Maybe try taking this further, an IR stack with a Visible stack to represent a wideband image?


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## that1guy (Aug 18, 2012)

try focusing before you put your filter on thats what we do before day time long exposures


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## mjhoward (Aug 18, 2012)

These don't look at all like IR to me.  You said you put an IR filter on the camera, but did you remove the IR cut-off filter from in front of the sensor?  In an IR image, the vegetation should be white and it isn't white in any of your photos, including the one you said was "as shot" with nothing done other than convert to jpg.


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## zombiemann (Aug 18, 2012)

I do focus before putting the filter on, sometimes the act of putting the filter on knocks it out of focus just a hair.  Not enough that I notice on my LCD when reviewing but when I get home and start processing I end up scrapping them.  

Mj, I have not done the full conversion on my camera.  I don't have the spare money for a dedicated IR only body. My camera doesn't have much in the way of IR cut off as it is. It's weak enough I can point a tv remote at it without a filter on and see the light from it. I am not sure why the vegetation is coming out so dark.  I have other shots using the exact same method I took these with that it did in fact come out white.  Actually there is a thread over in "Landscape and Cityscape" where I posted pics I took that came out as you mentioned.  http://www.thephotoforum.com/forum/landscape-cityscape/295054-playing-my-new-ir-filter.html


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## Bynx (Aug 18, 2012)

I guess I just cant appreciate what you have done. IR is just something I dont have any interest in.


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## zombiemann (Aug 18, 2012)

So you have no interest in IR yet you felt compelled to come comment?  I am truly confused...


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## DGMPhotography (Aug 18, 2012)

Well he's interested in HDR, not IR, but seeing as this is a combination of both, he would have some sort of interest I would assume.


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## Bynx (Aug 19, 2012)

Exactly as DGM says. Since this is the HDR forum and I am greatly interested in HDR my comments would be towards the HDR aspects of your picture. The area of blankness I mentioned is not a result of a breeze blowing across causing absolute loss of detail and creating a totally single gray tone. I have shot with IR film before and got decent weird results with vegetation turning white and people looking like ghosts, so Im familiar with IR. I quickly lost interest after a couple of rolls. Looking at your efforts, hasnt made me miss doing it again. Keep trying, you might get it some day. Just not today. I just checked out your other posts and I see you have no problems with blank areas that you have here. Whatever you have done different here, doesnt work. The images in Playing with your IR filter look in focus and somewhat ethereal with the weird colors. Again not my cup of tea but if you like that kind of thing, go for it.
On closer examination that blank area is only on the B&W and the Color version and doesnt appear in your red one so its caused by something you are doing and not what someone higher up is doing.


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## zombiemann (Aug 19, 2012)

Bynx, I'm not sure what exactly caused the issue but it was something in photomatix.  No matter what I tried the trouble area was there.  I merged them in photoshop and got a much better result.  A couple of clouds have a weird edge to them but the path looks about a lot better.


Here is another stack I tried from a different scene that I think turned out fairly well

View attachment 17553


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## unpopular (Aug 19, 2012)

Just because it doesn't "look like" an IR doesn't mean it isn't an IR. The question should be if the image is interesting or the technique worthwhile. I think combining HDR with IR is an interesting persuit, though I am not crazy about the false color aspect.

Whether it looks like how an IR "ought to look" is completely irrelevant.

I never much cared for commercial HDR applications, their proprietary tone mapping I think is often unreliable, and as a general rule I think exposure fusion is a better approach.

google "enfuse gui".


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## zombiemann (Aug 19, 2012)

Thanks Unpopular.  I'll spend some time over the next couple of days playing around with enfuse gui.. looks like its got a bit of a learning curve but I think it will be worth it.


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## unpopular (Aug 19, 2012)

It's only a learning curve if it doesn't work with the default settings. 99.95% of the time the default work out fine. It's really a no-brainer in most cases, and works very well.

One nice thing about enfuse is that it actually tends to decrease noise, rather than increase it. It doesn't really change so much change the data it's provided, but fuses the existing data into one image on a local level. Tone mapping OTOH makes a high depth image, and then adjusts it to fit. Tone mapping is inherently subtractive while image fusion is additive. (though the combination into a single HDR source is additive, of course)

The uncompressed output files are true 16 bit TIFFs, so provided that you feed it good data, you end up with significantly more data than you started with in any one exposure. Many tone mappers (not all) produce only 8-bit images.


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## Bynx (Aug 19, 2012)

I agree with you that the pic looks better without that patch. But Im not sure what you are trying to achieve. This might be a fantastic image from the method you are trying. But for an image Id like to look at, not so much. I kinda like your lake scene. Looks like late autumn that had no wind to blow the leaves off the trees. Another shot while still on the tripod without the IR filter might have been good. Then you'd have a summer, fall comparison look


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## zombiemann (Aug 19, 2012)

I unfortunately don't have a visible light duplicate of the first lake scene I posted, but I do have another lake scene that came out nicely.  I'm thinking maybe the first image (the old school house) might just be a poor choice of exposures.  

1. Visible light HDR


2. IR without the R/B Channel swap (3 exposures)

3. IR with red and blue channel swapped for "false color"


P.S. yea I know the branches at the top need to be removed/cropped out.  Right now I'm just trying to get an idea of if this is a viable methodology.


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## Bynx (Aug 19, 2012)

Now that might make a nice tryptic. Leave the branches there. It gives a bit more 3D look and establishes where you are.


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## zombiemann (Aug 19, 2012)

So riddle me this Bynx, in your opinion, lack of interest in IR not withstanding... Do you think this is a process I should continue to peruse and refine or am I spitting into the wind?


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## zombiemann (Aug 19, 2012)

Also is this kind of what you meant by "tryptic"?  It's a very quick and dirty attempt, just seeing if I understand you correctly


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## Bynx (Aug 19, 2012)

That tryptic is good. I was thinking of the 3 pics side by side.
Like I said Im not that familiar with IR photography other than the little bit Ive shot on film. Ive seen some spectacular shots done B&W which gave a beautiful wintery look to a nice green summer scene. I dont know what look you are after. Is there someone's work you have seen and are trying to go for? It seems a convoluted way to end up with an HDR image. I tried your version of the tryptic.


*Please note:  The member's profile indicates that his/her images are Not Okay to Edit.
Tks*


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## zombiemann (Aug 19, 2012)

No, not trying to emulate anyone else's work.  Quite the opposite really.  I'm not trying to make a name for myself or anything, but I like to try things that are unusual.  Anybody with a tripod and a little bit of time can do a passable HDR (note: if they put forth the effort, I know HDR isn't cruise control for cool).  I like to dabble in HDR and like I said in the original post, I've been bracketing my IR shots to cover my bases as far as exposure is concerned.  So I just kinda thought "what the heck, this might be neat" and what you see in this thread is the result


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## mjhoward (Aug 19, 2012)

unpopular said:


> Whether it looks like how an IR "ought to look" is completely irrelevant.



IMO it is completely relevant since I was suggesting that it wasn't even an IR image but rather a visible light photo with a red filter applied.  My suspicions seem at least mostly correct since the OP admitted the IR cut-off filter had not been removed from in front of the sensor, meaning most IR light is being filtered out.  The other giveaway is that the SOOC should look at least nearly black and white since IR is not in the visible spectrum. Again, I think establishing wether or not this was actually just a strangely filtered HDR photo rather than IR as the title suggests would actually be completely relevant, but you are entitled to your opinion.


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## unpopular (Aug 19, 2012)

Wait. So not even an Bandpass or Highpass filter was used? You can sort of get IR without removing the filter on the sensor, but you need to filter the visible spectrum first and provide a long exposure.


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## zombiemann (Aug 19, 2012)

I used a 720nm visible light filter when taking the source photos.. The three shots I stacked for the initial image (the one room school house) have an agregate total of 55 second exposure.  Many DSLR cameras can still "see" IR even with the built in factory filter over the sensor.  You can test this yourself by pointing a TV remote at the lens of your camera and watching live view as you press a button on the remote.  If you see a light flashing on the end of the remote, guess what.... your camera is picking up the IR light that is invisible to the naked eye. 


So please, before you call me a liar (which is exactly what you did in essence), have half a clue as to what you are talking about


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## zombiemann (Aug 20, 2012)

Just to take it one step further... Here is the filer I use:


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## mjhoward (Aug 20, 2012)

zombiemann said:


> So please, before you call me a liar (which is exactly what you did in essence), have half a clue as to what you are talking about



I swear this forum is littered with all kinds of reading comprehension problems.  I'm also fairly certain that I've got more of a clue as to what I'm talking about than you do.  I never called you a liar or even suggested that you were lying.  I did, however, suggest that the photo may not actually have any IR component to it, which you may not have realized.  I understand that your camera, which most if not all do, picks up the IR light from your remote.  That is one small range of NIR light out of a much broader spectrum.  It could be that nothing in that particular scene is reflecting the spectrum that your camera is sensitive to (meaning no IR) and all you are left with is the long exposure of visible light up to 720-750nm.  Sure your $8 filter might be advertised for cutting of everything shorter than 720nm but it is a VERY cheap filter and there will be some fall-off.  Like I said, your SOOC photo would indicate that vegetation reflects NO IR light while the sky reflects a relatively large amount of IR, which is the opposite of reality, hence my suggestion.  Now the second photo in your post #12, on the other hand, looks MUCH better and actually exhibits IR behavior.


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