Thanks @bnorthan That helps me understand.
Interesting that some of the algos don’t normalize integrated intensity at the end.
You seem to be talking about small differences above though - little details, slight differences:
I am thinking about the validity of the assumption that:
“The raw image and result image “should” have close to the same total integrated intensity”
Where does the logic from that come from? Its seems intuitive… but the harder i think the less i think it makes sense physically, and light doesn’t always behave intuitively!
Thinking out loud:
We are restoring contrast of the image: The OTF tells us that lowest frequency features should not lose signal in the lens, and so remain the same after restoration, but small features lose contrast strongly in the lens, and should gain contrast strongly because the OTF at high spatial freq. is small…
I’m thinking that this should mean that the total image intensity after restoration should be much larger than in the raw image, because we have failed to catch a bunch of signal, and especially so if the object structures contain a lot of very high spatial frequency, like a field of fluorescent beads???
Trying to think another way (my maths isn’t great, but I try to imagine things visually, like Feynman explains them)
Consider the way the low and high spatial frequency info goes through the lens:
The low freq goes at a low angle so the axial (z) component of its vector is close to 100% of its size.
But high freq. info goes through the lens at a high angle, so the axial (z) component of that high angle vector is much smaller.
We are doing far field imaging, so we mostly get the z (axial) components of the photons, and not much of the lateral components… don’t know if this is physically correct… but I try to imagine the physical mechanism of how the OTF gets to be the shape it is. And it is roughly triangular…
Would this mean that since we detect only a small amount of the total real signal from high frequency features, we should be correcting that systematic error, and this is what our deconvolution algorithms in fact do. Boost high frequencies, but not the lowest one, according to the shape of the OTF.
I guess I’m still looking for a “physical justification” of why the raw and reconstructed images “Should” have the same integrated intensity, especially for structures that contains lots of fine detail, high spatial freqs.
any clues on this assumptions correctness?