Photographing red hot steel question. (1450-2200F) color distortion

[Liamh]

Hi everybody. First off, glad to be apart of this forum. I am purchasing a D5200 to take pictures of my work, as a professional Blacksmith with a Tamron 18-270MM lens.

My question for you all is this - Will a special density filter or UV filter be necessary for photographing and filming hot steel. The steel puts off a lot of light which causes those weird purple hazy colors to show up. Basically a smart phone camera or cheap digital camera shows this as a yellow blob, whereas i'm looking for detail. Could any insight be given to this very specific question?

Thanks in advance,
Liam :sillysmi:

 

[Derrel]

I dunno about steel, but on hot things like fire and the coals in a fire, OVER-exposure tends to create a bad-looking, yellowish tint on what SHOULD be a hot coal-orange coloration. In many situations where there is very HOT material, the surrounding environment is often very,very dark, like soot-covered-metal-black for example, so in-camera light metering that is not a narrow spot meter reading will tend toward seriously over-exposing the hot, firey bits, due to the overall amount of dark material that surrounds the hot material. In many digital systems, greatly over-exposed, lighted bodies (like the sun, or lights) can take on that ugly, detail-less yellow color.

I do not think you need any filters at all to photograph hot metals, but you WILL need to figure out how to arrive at PROPER exposure settings if you want the color to be good. If you ALSO want dark, surrounding material, like a forge, or a dark crucible, or sand molds, etc.etc. to look good, you would actually want to bring in ancillary light for the "dark stuff". Flash would work I think, to bring the darks "up" close to the molten metal.

I can envision that a Neutral Density filter might be helpful to cut down on the brightness of hot, molten metal when shooting video, so you do not need to be at f/22 all the time.

 

[lambertpix]

Part of the problem here is likely the huge dynamic range between the light of the steel and the ambient lighting conditions. I'm not sure if this is exactly equivalent, but I've found that fill flash can help even the lighting on shots like this:

IMG_1705.jpg by lambertpix, on Flickr

IMG_6201.jpg by lambertpix, on Flickr

 

[Derrel]

That is **exactly** the issue I was talking about....molten material that's realllly bright...and then the dark stuff that is outside of the forge/furnace/etc.. Like, look at the glory hole in the glasswork shot at bottom; the exposure there is incredibly much brighter than say, on the woman's blue and black shirt...without fill-in light, she would be barely more than a silhouette...

 

[lambertpix]

That is **exactly** the issue I was talking about....molten material that's realllly bright...and then the dark stuff that is outside of the forge/furnace/etc.. Like, look at the glory hole in the glasswork shot at bottom; the exposure there is incredibly much brighter than say, on the woman's blue and black shirt...without fill-in light, she would be barely more than a silhouette...

Points to Derrel for best use of "glory hole" in a non-locked thread. And yes... that's exactly what they call it. ;-)

 

[pthrift]

That is **exactly** the issue I was talking about.. Like, look at the glory hole

I fixed it so now it's the quote of the day. geez its only 2pm, and we already have a winner

 

[Liamh]

Ha Ha thanks for the insight guys, so now I understand that the main problem is the contrast in environments.

Derrel, since I will be photographing AND filming you suggest a neutral density filter for the filming. I'm totally new to this. I'm on B&H right now looking at 62MM Hoya filters. I'm looking at one in the $100 price range and they're all $85.90, except they all have different "stop" amounts, and optical density amounts. Off the top of your head do you think that you could recommend one with a proper amount of stops and an optical density amount for the kind of work it will be seeing.

Thanks for the information guys and gals

 

[Liamh]

Derrel, can you recommend a filter stop amount for filming?