difference in heliars

[absolom]

It's been a while but I'm getting back in LF and I'm interested in buying a heliar. Can someone explain the difference between older and newer heliars to me? Should I avoid older heliars? Does it matter? I can't find a lot of information about them other than the fact that people like them and I also like the photos I've seen taken by them.

Thanks in advance!

[Tracy Storer]

Use google site search of this site. Lots of good info already shared.

[dasBlute]

thus... google: heliar site:https://www.largeformatphotography.info

[erian]

If you find a dead link then check https://archive.org/

Changes are that it is archived.

[Ken Lee]

See A Short History of the Heliar Lenses (http://www.antiquecameras.net/heliarlenses.html)

I've never seen anyone do a rigorous Heliar-only study where they shoot an unchanging subject under unchanging conditions and simply change the lens - but having made photos with a few Heliar lenses, I would refer you to our own Christopher Perez's study of out-of-focus rendition of non-Heliar lenses, since the principles are the same.

See "Out of Focus Rendition Studies" at http://photosketchpad.blogspot.com/

Here are some questions to keep in mind when comparing:

Given that a lens renders in-focus areas with adequate sharpness, what happens in front of and behind the plane of sharp focus: are optical aberrations over-corrected or under-corrected ?

What do under-, over-, and properly corrected aberrations look like ? As we stop down the lens, do the aberrations go away ?

How far do we have to stop-down a given lens before aberrations are controlled ? Do all lenses behave the same once we reach a certain aperture, or are there some which never lose their aberrations no matter what we do ?

Do some lenses have controls which let us vary the aberrations, independent of aperture ?