Cylindrical lenses and linear flare...

Would an optically flat filter made from a doublet of cylindrical lenses create linear flare like anamorphic lenses do?

Unless I can find some suitable lenses on Aliexpress or something to experiment with it could be very expensive and/or time-consuming to find out for myself...

So here I am!

The lenses are colored differently for illustration, but would be made from the same glass type in reality.

For the record, I do know anamorphic lenses (or attachments, of which I currently have a few), streak filters, and fishing line exist. 

I don't think its inherently better - though you could potentially have better control over CA compared to a hunk of glass.   You can model this in an optical software to figure it out.   Also EO and so on may have off the shelf cylindrical lenses which you can get specs for.   I know its possible for anamorphic optics to eliminate most of this, like the arriscope lenses and others for which there may be patents or lens formulas disclosed.

I know thats not the answer you wanted.

Thanks for responding, BobORama!

BobORama wrote:

I don't think its inherently better - though you could potentially have better control over CA compared to a hunk of glass.

You can model this in an optical software to figure it out.

I'll have to look into what my options are, starting with things that are free / open-source hehe.  Zemax is $$$.

Also EO and so on may have off the shelf cylindrical lenses which you can get specs for.

They are a great resource.  I've indirectly picked up some of their bits and bobs over the years.

I know its possible for anamorphic optics to eliminate most of this, like the arriscope lenses and others for which there may be patents or lens formulas disclosed.

I'm looking to *introduce* linear flare, not eliminate it, all while leaving bokeh mostly unaffected (something that streak filters and fishing line do NOT do - they leave lines in bokeh balls).  A filter made as I propose could end up being a very costly, thick, and heavy piece of glass that would surely introduce its own aberrations and shift focus quite a bit, so I know it has its own set of problems.  But if it works... In combination with an elliptical aperture insert in a spherical lens, it could create a pretty convincing "anamorfake" that would be much easier to use than, say, a dual focus anamorphic attachment both during shooting and in post.

I know that's not the answer you wanted.

Again, thanks for responding - I'll take any answers I can get!

Tons o Glass 0 Class wrote:

I'm looking to *introduce* linear flare, not eliminate it, all while leaving bokeh mostly unaffected (something that streak filters and fishing line do NOT do - they leave lines in bokeh balls).

There are always diffraction gratings... although they'll color the flare. I also can imagine some shiny things being placed at the rear of an adapter tube to created a linear flare pattern. Lindsey Optics has some pretty freaky-looking filters that are pretty close to the fishing-line concept, and yes, they will change the OOF PSF (out-of-focus point spread function) and hence the bokeh.

However, this is really pretty easy to fake in post. Basically, you'd just isolate the bright spots, directionally smear them, and then apply them as a lighting effect to the original frame. Not necessarily easy to get right by hand, but very similar to what I did back in 2012 to credibly repair Fuji "white orbs" . That turned:

Into:

A few months back I purchased a large (60x51mm) negative (-300mm) cylindrical element from SurplusShed. The recent Moment CineFlare filter announcement reminded me do get going on this experiment again.  To get a second element I 3D-printed a holder/mold for the negative and poured clear resin over it.

Once cured there were no reflections from the cylindrical surfaces because they were so perfectly bonded, so I wasn't getting any linear flares. Once I got it separated (which would have been easier if I had designed the mold with that in mind hehe) and [barely] air-spaced, the flares I was looking for showed up easily!  They were faint and more tasteful than those found with streak filters or fishing line, which to me are over the top.

If at least one of the cylindrical surfaces was single-coated prior to being cemented (the element I bought was uncoated, dang) would the linear flares (or is it technically ghosting?) take on the hues of the coating's reflections, or is the airspace needed to get any flares at all?