I borrowed a Fluke thermal camera from work over the weekend and snapped these infrared pics of my old Jotul #8 doing the "ignition sequence start" thing. Thought folks here might be interested... though I'm sure someone's posted these kinds of images here in the past.
The pictures were taken at roughly 0, 2, 5, 20, and 40 minutes after light-off. The first four all use the same 350F temperature scale, but on the fifth (#0116) I re-scaled to 650F because most of the image was above 350F and thus blown-out. (I also left my coffee cup on the stove while taking the pic.) The first two pics show uneven heating of the stove since the door is ajar for start-up air (opens on left, hinges on right).
The last pic is outside looking up at my stainless stovepipe, and illustrates one of the pitfalls of IR temperature measurement (including the handheld single-point guns)... emissivity correction. The glowing patch on the side of the stovepipe that the camera measures as 126 degrees is just the remnants of the paper label that was on the polished stainless pipe. The rest of the pipe, that the camera thinks is 64 degrees, is almost certainly the same 126 degrees as the label... maybe a little hotter. But because polished stainless has an emissivity of 0.1 or less, whereas paper is 0.9 or more, the temperature reported for the polished metal is cooler by a factor of two or so. (The soot inside the cap is a pretty good IR emitter, too.)
Eddy
The pictures were taken at roughly 0, 2, 5, 20, and 40 minutes after light-off. The first four all use the same 350F temperature scale, but on the fifth (#0116) I re-scaled to 650F because most of the image was above 350F and thus blown-out. (I also left my coffee cup on the stove while taking the pic.) The first two pics show uneven heating of the stove since the door is ajar for start-up air (opens on left, hinges on right).
The last pic is outside looking up at my stainless stovepipe, and illustrates one of the pitfalls of IR temperature measurement (including the handheld single-point guns)... emissivity correction. The glowing patch on the side of the stovepipe that the camera measures as 126 degrees is just the remnants of the paper label that was on the polished stainless pipe. The rest of the pipe, that the camera thinks is 64 degrees, is almost certainly the same 126 degrees as the label... maybe a little hotter. But because polished stainless has an emissivity of 0.1 or less, whereas paper is 0.9 or more, the temperature reported for the polished metal is cooler by a factor of two or so. (The soot inside the cap is a pretty good IR emitter, too.)
Eddy
