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split focus

Started Dec 3, 2018 | Discussions thread
petrochemist Veteran Member • Posts: 3,619
Re: split focus

SmoothOperator wrote:

There are some nice split focus filters out there, but I'm wondering if other lenses like a pair of bifocals can be repurposed, or these graded optometrist test lenses, that step up a quarter of a diopter.

Does anyone make a circular splitfocus, where the center is closer, and the outside can be focused on the background. Somewhat like the minolta variable field lens.

I've never seen anything like that sold for photographic use. I do have a few strong aspherical lenses elements for playing around with where the strength varies across the radius. I've not yet managed to get anything looking remotely like an image with them!

Does the accessory lens need to have the same optical center, or can you basically wave a magnifying glass in frontof the lens.

You can just use a magnifying glass the image quality probably won't be quite as good. In experiments I've actually used Fresnel lenses too (IQ definitely takes a hit with these)

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