These days I'm gradually realizing that Meniscus solution is unmanageable for me, unlike much simpler PCX solution.
In theory, meniscus front-end filter can also correct both field curvature and astigmatism, perhaps even better than PCX in some conditions.
However, the correction effect of meniscus lens is very sensitive to the parameters below:
1. Curvature radii of both side: we can't measure these accurately without using professional equipment. Even very small difference of these curvature induce visible correction error.
2. Distance between the meniscus filter and the primary lens: even 1mm difference of this gives visible correction error. Also I can't set this distance precisely in my simulation bench without knowing the primary lens' technical details.
3. Assembly variation of the filter: small decentering and tilt give visible correction error.
When we use PCX, all of these parameters give much smaller effect to correction results so things are much easier.
I'm not saying negative to use Proxar lenses for correction by trial and error method, but it seems difficult for me to simulate its behavior
Fred Miranda wrote:
@HaruhikoT@ ,
Would a Proxar 1m lens have similar optical characteristics to a Minolta 1m close-up filter for example? They both seem to be meniscus lenses.
From your modeling, how would do they differ from a PCX lens as far as correcting FC and astigmatism?
If they are similar in your software simulation results, what would be the positive and negatives of each approach?
