Focusing

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when using digital (Phase one), very often I have difficulties focusing with tilting/swinging. How can I overcome? will using a focusing lupe which is stronger (15X or20X) helps me? At the present I am using a 8X Lupe. Thanks for your input. Regards T

-- Theo Tan (aperture@internet.look.ca), August 09, 2001

Answers

Theo - a higher magnification lupe will not help your focusing, most recommend 4X lupe. When using movements, your plane of focus will change, along with the shape of your DOF - to obtain a sharp image across the whole film area may require additional movements, or stopping down - there are articles and threads in this forum on both. There are many basic principles on how the shape of images change with back movements, and how your focus plane/DOF changes with front tilts/swings. Try looking through some of the previous threads and articles - also a good book is Leslie Strobels "View Camera Technique". If you could be more specific in the type of focusing problem you have, I'm sure someone here could help you.

-- Michael Mahoney (mmahoney@nfld.com), August 10, 2001.

Sorry, Theo just saw the "digital" in your question, so I really don't know if I've given you the correct info or not - does anyone know if there is a difference with the digital vs. regular lenses?

-- Michael Mahoney (mmahoney@nfld.com), August 10, 2001.

Theo,

Are you using a small MF CCD phase one, or are you using a 4x5" phase one scanning back?

-- edward kang (ekang@cse.nd.edu), August 10, 2001.


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