Random Photos...

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FeelioBabar

Trad climber

One drink ahead of my past.

Apr 10, 2011 - 10:24pm PT

The Larry

climber

Moab, UT

Apr 11, 2011 - 12:11am PT

Mike Bolte

Trad climber

Planet Earth

Apr 11, 2011 - 12:26am PT

neebee

Social climber

calif/texas

Apr 11, 2011 - 07:01am PT

hey there say, here's one....

the grandkids found it.... in our old shed:

and, i found this... naturally, THIS was in my HOUSE:

WELL, all for now.... think i can sleep now...
:)

perswig

climber

Apr 13, 2011 - 04:03pm PT

Banquo

Trad climber

Morgan Hill, CA (Mo' Hill)

Apr 22, 2011 - 06:25pm PT

Infrared cameras love full, bright, harsh sunlight. I am looking forward to taking it rock climbing.

Mike Bolte

Trad climber

Planet Earth

Apr 23, 2011 - 01:21am PT

damo62

Social climber

Brisbane

Apr 23, 2011 - 02:17am PT

Banquo Bro, how did you do that? Pretty Please.

perswig

climber

Apr 23, 2011 - 06:21am PT

Nice additions! Pretty cool, Banquo.

Dale

(Edit: may be a repost to this thread?)

Captain...or Skully

climber

My ready room

Apr 23, 2011 - 08:45am PT

Tiny snapper! Very cool, Dale.

Banquo

Trad climber

Morgan Hill, CA (Mo' Hill)

Apr 23, 2011 - 08:47pm PT

Converting a camera to infrared (IR)

All digital cameras can sense IR but they have a little filter in front of the lens that blocks the IR so your photos look natural. All you have to do is take the filter out (it's called a hot mirror) and replace it with either a clear glass or something that blocks all or most visible light.

There are services that will do this for $200 and up but if you aren't too picky about results and are handy with little parts, it isn't too hard to do for free. The hardest part is getting the camera apart and back together again. Luckily, there are lots of geeks on the internet who like to take cameras apart and post step by step instructions. Sometimes you can find service manuals, parts lists or exploded parts diagrams that help.

STEP 1
Find, borrow, steal or buy on ebay the cheapest digital point and shoot you can find for your first project. I had a Canon A550.

STEP 2
Take it apart until you can get at the sensor. Sometimes you get at this from the back and sometimes from the lens side.

STEP 3
Find and remove the hot mirror. It's a little piece of glass that looks almost clear. Mine was about a centimeter across.

STEP 4
Find something to replace the hot mirror with. I used a piece of very over exposed and developed color negative film. When you get a roll of film processed, the tail that hangs out in the light when you load the camera. It will look pretty much black after developing. I've seen people cut a piece of the magnetic disc from inside an old floppy. A piece of black garbage bag might work. Hopefully it is about the same thickness as the old hot mirror (mine was 0.009 inches thick).

STEP 5
Put the camera back together. Usually harder than getting it apart. Like down climbing. I hate that term down climbing, I prefer to call it unclimbing. "I climbed the pitch and then I unclimbed the pitch."

STEP 6
Go take pictures. They will look pretty weird right out of the camera. If your filter is good at blocking all visible light, it will probably be red and black. My filter seems to let some visible spectrum through so of RGB I get some red and green but not much blue.

Banquo

Trad climber

Morgan Hill, CA (Mo' Hill)

Apr 23, 2011 - 09:05pm PT

The leaves and clouds reflect the IR but the sky is cool and dark. Seems to work best in full sunlight. Best cloud pictures ever. It seems to see more clouds than the eye.

Mike Bolte

Trad climber

Planet Earth

Apr 23, 2011 - 09:25pm PT

this is neat Banquo,

an interesting little aside, the detectors in most digital cameras are CCDs and they lose sensitivity by around 8000A=800nm. This is considered the red end of the optical part of the spectrum, not the true infrared that is usually defined to start at around 1micron=1000nm. For sure the light in these "infrared" images is reflected red light not emitted infrared from the objects in the scene.

Banquo

Trad climber

Morgan Hill, CA (Mo' Hill)

Apr 23, 2011 - 10:19pm PT

Mike, very true.

I think this is more correctly called near infrared photography and shouldn't be called thermal imaging. I've shamelessly snatched some plots off the net, one for CCD's and one for visible. A bit confusing because the scales are reversed.

When I hold my filter up to sunlight, I can't see through it so I think the camera is capturing something outside the visible range. Pretty crude filter and camera so it's hard to say what the image spectral range is. I suspect it is partly in and partly out of at least my visible range. The lens glass also filters and may have coatings.

I suppose visible range varies from person to person.

The images remind me of moonlight. I'm too lazy to research this but it may be that moonshine is in the near infrared.

The two images posted here were taken at f2.6 1/640 and ISO 200 in full sunlight. This is maybe 3 stops down from a "normal" camera so there is a fair amount of light getting through my black filter.

Edit:
Chlorophyll has absorption peaks in the blue range and in the orange-red range. The bright white of the leaves in my pictures is light beyond 750 nm. The green we see is the light between 450 and 650 nm which is reflected.