Is Digital Infrared Interesting? (Corrected info on filter)

Visited a local sculpture park with a “full-spectrum” EM5 Mk1 and UV and blue filters.

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I think it’s certainly interesting! :smile: Personally, I’m itching to try messing with the colour channels or WB on some of the images to see if I could get a less ‘orange all over’ look, but no idea if it even possible. Thanks for sharing!

I can do a raw play later today

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:smiley:

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Hey @TonyBarrett these are really fun! The colors are nice.

For the first one, I’d crop out the sky in the upper left.

For the second one, I’d crop out the fence on the right.

For the last one, I’d straighten the lines in the foreground using rotation, and crop the sky in the upper left. Then I think it would be excellent. Its the kind of frame I’d go back and shoot again and again.

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It is definitely an interesting look. And I think a lot more definition in the “greens” of the plants.

What is a “hot mirror”?

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Thanks. Agree on your points. That big hole in the foliage is distracting without an interesting sky. (The scene didn’t need IR but I didn’t bring a conventional camera as I didn’t expect such a relatively conventional scene at the sculpture park). I did try to crop the top of the last one at first but then the figure was even nearer the top of the frame. Could reshoot at some point.

CORRECTION: It’s not a hot mirror filter, it’s a UV filter… sorry, misremembered.

The UV filter, combined with a green-blue filter, gives an approximation of Kodak Aerochrome film, with orange-red foliage and fairly normal looking blue skies without having to do any channel swapping with the channel mixer.

I think I may have got all that from here:

Kolari Vision produce a more expensive single “IRChrome” filter that does something similar:

Sure it is! Really like the look here.
Reminds that I have a Pana GM1 with a half-broken sensorfilter lying around, might as well finally rip that out for good.

Here is what I do not get about the hotmirror filter, please tell me where I go wrong.

So every regular camera has a hotmirror installed by default to cut out UV and IR. By adding a hotmirror filter to your fullspectrum camera you basically get a regular off-the-shelf camera. Then you add a blue filter. So your raw file has all information in the blue channel and depending on the strength of the filter little to none in both red and green.

So how does the foliage turn orange???

Edit: just saw the images posted in PlayRAW, thanks a lot. Will take a look at them. =)

CORRECTION: Ignore all this, I used a UV filter, not a hot mirror filter…

I guess these cheap hot mirror lens filters are not as good as the manufacturer installed filters on your sensor. I did wonder why the blue green doesn’t filter out the blue of the sky so much. I think the link on the ultraviolet photography website may go into that, from memory.

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Now that makes so much more sense!! :bulb: :joy:

Thanks for the update!

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I looked the “hot mirror” up. It’s really a mirror, but for infrared light. Shorter wavelength (visible and UV) pass through. A filter would absorb the energy and get warm. Reflecting the heat is cool. :slight_smile:

The UV part can then be absorbed in the glass carrying the mirror.

(and now I am reading up about Bragg mirrors…)

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Just in time Barney Britton posted his own first experiences with a fullspectrum camera:

https://www.dpreview.com/articles/5738504587/here-s-what-happened-when-i-converted-a-panasonic-s1r-to-full-spectrum-imaging

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I think that it is very interesting.
Although I do not master the technique of infrared photography.
I share these links of a photographer who reveals his files with Darktable, I hope they are useful.
On their website there are examples of how interesting infrared photography can be, and his youtube channel.
Greetings…

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I really like his channel (and his German accent in English is quite soothing)

Interesting. Thanks for pointing it out. I’ve never tried shooting full spectrum without a filter

That’s the guy who did my K-5 conversion for me. Great service and good introduction to IR shooting to.

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