Hi all,

I'm open and debayering 3 Light frames which were recorded with DSLR at 28 C temperature with ISO1600.

Noise evaluation for those 3 files reports:

Gaussian noise estimates:

s0 = 1.331e-003, n0 = 0.212 (MRS)

s1 = 1.282e-003, n1 = 0.283 (MRS)

s2 = 1.319e-003, n2 = 0.216 (MRS)

Gaussian noise estimates:

s0 = 1.359e-003, n0 = 0.210 (MRS)

s1 = 1.308e-003, n1 = 0.280 (MRS)

s2 = 1.349e-003, n2 = 0.214 (MRS)

Gaussian noise estimates:

s0 = 1.329e-003, n0 = 0.210 (MRS)

s1 = 1.280e-003, n1 = 0.280 (MRS)

s2 = 1.319e-003, n2 = 0.215 (MRS)

Now, to calibrate those I'm using Master Bias which created from 250 Bias frames at ISO1600 and Master Dark which created from 30 Dark frames at ISO1600 with exactly same 28 C temps.

After calibration with Master Bias and Master Dark with noise scaling and debayering I'm getting noise evaluations accordingly:

Dark scaling factors:

k0 = 1.491

VNG debayering: done

Noise evaluation: done

Gaussian noise estimates:

s0 = 1.013e-003, n0 = 0.556 (MRS)

s1 = 9.803e-004, n1 = 0.700 (MRS)

s2 = 8.908e-004, n2 = 0.544 (MRS)

----------------------------------------------

Dark scaling factors:

k0 = 1.500

VNG debayering: done

Noise evaluation: done

Gaussian noise estimates:

s0 = 1.024e-003, n0 = 0.555 (MRS)

s1 = 9.927e-004, n1 = 0.700 (MRS)

s2 = 8.972e-004, n2 = 0.541 (MRS)

-------------------------------------------------

Dark scaling factors:

k0 = 1.544

VNG debayering: done

Noise evaluation: done

Gaussian noise estimates:

s0 = 1.007e-003, n0 = 0.553 (MRS)

s1 = 9.766e-004, n1 = 0.699 (MRS)

s2 = 8.818e-004, n2 = 0.541 (MRS)

After calibration it shows that only channels R got reduced in noise in all of the three files and channels G and B got injected with noise.

Can someone explain what's going on here?

I have also run calibration on those files without dark scaling and got those noise evaluations accordingly:

s0 = 1.042e-003, n0 = 0.417 (MRS)

s1 = 1.001e-003, n1 = 0.539 (MRS)

s2 = 9.275e-004, n2 = 0.388 (MRS)

s0 = 1.059e-003, n0 = 0.404 (MRS)

s1 = 1.019e-003, n1 = 0.525 (MRS)

s2 = 9.407e-004, n2 = 0.372 (MRS)

s0 = 1.037e-003, n0 = 0.412 (MRS)

s1 = 9.977e-004, n1 = 0.534 (MRS)

s2 = 9.198e-004, n2 = 0.381 (MRS)