sgfriend said:Like to know what is achromatic macro lens for? :dunno:
sgfriend said:What i have was a Sigma achromatic macro lens. So when I set the Sigma 70-300mm into macro mode and use it to become macro and more macro?:dunno:
student said:There are two aspects to the description of this lens
1 Achromatic
2 Macro
"Macro" as explained by blurblock is a "magnifying glass"
Now for "achromatic".
A single lens causes colored fringes around images because the lens diffracts the different wavelengths in white light to slightly different extents.
An "achromatic" lens uses a combination of lenses to reduce this color aberration.
MDZ2 said:I think the term is Apochromatic or APO for short. These are coatings on lenses that filter out different wavelengths of light. Without these, you will tend to get images with chromatic aberations or rainbows at the edges of images. its especially pronounced when using long lenses and in broad daylight.
MDZ2 said:I think the term is Apochromatic or APO for short. These are coatings on lenses that filter out different wavelengths of light. Without these, you will tend to get images with chromatic aberations or rainbows at the edges of images. its especially pronounced when using long lenses and in broad daylight.
MDZ2 said:I think the term is Apochromatic or APO for short. These are coatings on lenses that filter out different wavelengths of light.