1200*C - 2000*F is how hot the yellow flowing lava at the back of this cave, and about 800*f in the orange-red parts… Shot with a 24-70mm lens.
I was shooting into the lower end of a large square shaped fissure that had a cave at the back end. Surface lava was flowing from the top down into back end and sides of the cave & fissure; pooling together and moving toward me while rolling and twisting into pahoehoe bands. The fissure walls kept the advancing lava fluid much longer than it would have been across a surface exposed to more air.
Yes it was very difficult and hot to get this image. I took it recently while documenting the continuing lava flows on the south slopes of the Island of Hawaii.