PDA

View Full Version : Soft focus lenses; anastigmats or not?



Mark Sawyer
1-Mar-2007, 16:32
Just wondering... of the popular soft-focus lenses (Verito, Imagon, etc.), are these considered anastigmats or not?

Ernest Purdum
1-Mar-2007, 17:46
Neither of those you mention are anastigmats. There have been several anastigmats with soft-focus capability, usually by changing element separation to add some spherical aberration.

Amongst the articles at the bottom of the home page, you will find an article which gives more detail on this subject.

Jim Galli
1-Mar-2007, 22:54
Typically, the anastigmats are the least soft and fuzzy of the "soft focus" lenses. Cooke Portrellic and Portronic, Voigtlander Heliar, Wollensak Velostigmat are all anastigmats and all share a similar look. Kind of a very smooth creamy sharp. A fine look at f4.5 and often just what the situation calls for.

Mark Sawyer
2-Mar-2007, 00:10
Thanks Earnest. I just wasn't sure whether the older designs (Verito...) or achromatic doublets (Imagon...) were corrected for astigmatism.

And I agree, Jim, the adjustible diffusion Velostigmats are wonderfully smooth and much more subtle than most soft-focus lenses. But, for the moment, I'm throwing subtlety aside... :)

Pat Hilander
2-Mar-2007, 10:52
The Graf Variable's are also anastigmats with the adjustable soft focus control on the front. I just got one cleaned up and mounted to a speed graphic board last night. I'll test it out this weekend.