wickerprints
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Again, at the risk of being pedantic....
Reducing the problem of chromatic aberration *requires* the use of at least two different materials of different dispersion. That is the basic principle of an achromat. It's not simply that a given design might have one or more low-dispersion elements, UD or fluorite. For example, the traditional achromatic doublet uses crown and flint glass, neither of which is particularly "low dispersion." But to achieve even better correction of secondary spectrum we need to use another material and this is where fluorite or fluorite-doped glass comes into play.
That is to say, low dispersion glass in itself doesn't entirely fix CA. If you made the entire lens out of it, you would certainly see less CA than if you made it out of normal glass (assuming refractive index is the same but it won't be), but it still won't be an achromat or apochromat. The key to correction is different materials, not necessarily a material with low dispersion. You take one element with one dispersion characteristic and positive refractive power, cement it to another element with another dispersion characteristic and negative refractive power, and if calculated correctly, you get a doublet with net refractive power (positive or negative) and some degree of correction where red/blue wavelengths are made to focus.
Personally, I believe there is still much reason to continue R&D in optical glass to reduce CA of all kinds. First, the amount of CA depends strongly on the design of the lens, with retrofocus and telephoto designs being particularly prone to CA. You can see this especially in UWA zooms, in which the corners are almost inevitably marred by strong transverse CA. We would see a lot more CA in the supertelephotos were it not for the use of low-dispersion or fluorite glass. What is not as obvious is that CA is the primary reason for differences in sagittal and meridional MTF in superteles, not astigmatism which is inherently small for long focal length (due to small angle of view -> low field curvature).
So when we talk about wanting to keep things simple and not use fancy constructions, that's well and good for a 50mm prime, but it just isn't going to fly with a 16/2.8 or 500/4. You can't rely on software to correct this because CA manifests in a variety and combination of forms, not just the familiar transverse CA in which the image is sharp but magnification varies by wavelength. It is undesirable to have to software correct for longitudinal CA and overall haze/loss of contrast due to CA. Distortion is probably the easiest aberration to correct in post--even the "mustache" distortion can be corrected if one collects the relevant data. But spherical, chromatic, astigmatic, and comatic aberrations are best corrected in the lens.
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