I'm doing a physics research project on lenses.

[Jaszek]

What are some questions you want answered? This is what I have so far:" . How can lenses be combined to achieve different effects? (eg. Zoom, wide angle) How can you achieve different effects using different types of lenses and glass “filters”? (eg. Polarizers)". Let's hope my teacher doesn't see this .

 

[Joves]

What are you lookig for the diffrent types of elements and, how their individual curvature effects them? That is a fair amount of math and, Im not in the mood to do the math. go here and have a look see. Stops and Apertures

 

[Jaszek]

thanks for that link. I have time until may or something like that si i'll have time to do the calculations lol.

 

[Eldrich]

What level of class is this? There are plenty of topics that are interesting.

I think many photographers could benefit from understanding the actual physics behind light polarization. I think there's a fair amount of misunderstanding about what polarizers actually do, and also about what circular polarizers do and why they're needed. But I guess thats technically not the lens.

Chromatic aberration is also pretty interesting. Do many photographers actualy know what it is? You could look into the frequency dependence of the index of refraction of different types of glass, and talk about low dispersion glass.

There's also a lot of interesting developments happening in dielectric coatings these days, which is why they are showing up more and more on photography optics for cheaper and cheaper. They are mainly used for antireflective coatings on filters and on lenses I think. But you could look into how dielectric stacks of thin films can have broadband antireflective behavior.

I think if you're going to do something regarding the bokeh and depth of field I think its probably not the best physics project to look up DOF equations online (which there are plenty) but rather look into the equations that lead to bokeh effects. Such as the deviation of a lens from the 'ideal' shape as you move off of the center of the lens.

There's also a fair amount of interesting topics in terms of defects. How large would a grain of dust have to be on your lens before you can resolve it in the photo?

anyway, sorry, grad student in an optics lab, you tickled my funny bone...

 

[Jaszek]

Well its a high school physics class...and my teacher is a photographer also so he wouldn't mind me doing this topic lol

 

[astrostu]

For a HS project, I'd say going into methods of removing CA and spherical aberration would be reasonably appropriate and interesting. Getting into polarization may be more of a college-level project.

You could also look at diffraction effects, so why camera lens sharpness degrades at high f/stops, and you could also look at the reverse of that, why it degrades at the widest apertures, too.