Very nice question!

Let's look at the frequency distribution of a halogen lamp:

You can see that all frequencies are present (hence the white color). The temperature of the burning lamp is about $800$ Kelvin. If you polarize the beam nothing, in particular, should happen because the photons have a random distribution of polarization. The intensity should obviously get less (with a polarization filter).
Did you change the settings of the camera? I think you have to (why did you use two filters, by the way?).

I can think of nothing else to conclude that the metal reflects the light in such a way to produce your observation(s). Paper reflects in a completely different manner. Try using another metal.

Let's look at the frequency distribution of a halogen lamp:

You can see that all frequencies are present (hence the white color). The temperature of the burning lamp is about $800$ Kelvin. If you polarize the beam nothing, in particular, should happen because the photons have a random distribution of polarization. The intensity should obviously get less (with a polarization filter).
Did you change the settings of the camera? I think you have to (why did you use two filters, by the way?).

I can think of nothing else to conclude that the metal reflects the light in such a way to produce your observation(s). Paper reflects in a completely different manner. Try using another metal.

See also this article. Maybe you have already seen it, maybe not, but for sure it contains information for your project.

Very nice question!

Let's look at the frequency distribution of a halogen lamp:

You can see that all frequencies are present (hence the white color). The temperature of the burning lamp is about $800$ Kelvin. If you polarize the beam nothing, in particular, should happen for the photons have a random distribution of polarization. The intensity should obviously get less.
Did you change the settings of the camera? I think you have to (why did you use two filters, by the way?).

I can think of nothing else to conclude that the metal reflects the light in such a way to produce your observation(s). Paper reflects in a completely different manner. Try using another metal.

Maybe this is of some importance (though it's not related to reflection) One can read the following question here:

How can I obtain a circularly polarized light with Tungsten Halogen light? I'm the graduate student Po-Yang Wu of Taiwan National Cheng Kung University. I have bought an optical element (AQWP05M-1600) form Thorlab company, but I have some problems now. The problem I want to ask is that whether I can use the combination of a polarizer (Glan-Thompson, 300~2300nm) and achromatic quarter waveplate (1100~2000nm) to generate a circularly polarized light with Tungsten Halogen light (350~2300nm). Or the light source only can be a laser light source?

Very nice question!

Let's look at the frequency distribution of a halogen lamp:

You can see that all frequencies are present (hence the white color). The temperature of the burning lamp is about $800$ Kelvin. If you polarize the beam nothing, in particular, should happen because the photons have a random distribution of polarization. The intensity should obviously get less (with a polarization filter).
Did you change the settings of the camera? I think you have to (why did you use two filters, by the way?).

I can think of nothing else to conclude that the metal reflects the light in such a way to produce your observation(s). Paper reflects in a completely different manner. Try using another metal.