Do glass lenses produce sharper images than plastic lenses?

Discussion in 'Film Discussion and Q & A' started by Ap22@, Apr 20, 2017.

  1. Ap22@

    Ap22@ TPF Noob!

    Joined:
    Apr 20, 2017
    Messages:
    1
    Likes Received:
    0
    Can others edit my Photos:
    Photos NOT OK to edit
    Hi there

    I'm looking to get on of those Lomo'instant Automat cameras. I see they have a new version that comes with glass lenses.
    My question is, should I go for the slightly more expensive model and buy the one with glass lenses assuming it produces sharper images?

    Thanks


     
  2. mdruziak

    mdruziak TPF Noob!

    Joined:
    Nov 9, 2009
    Messages:
    74
    Likes Received:
    7
    Location:
    Rochester NY
    Can others edit my Photos:
    Photos OK to edit
    Lomo is not about sharpness. I think the main benefit of the new version is autoexposure.
     
  3. petrochemist

    petrochemist TPF junkie!

    Joined:
    Mar 9, 2014
    Messages:
    1,673
    Likes Received:
    494
    Location:
    North Essex UK
    Can others edit my Photos:
    Photos OK to edit
    I'm sure I have some glass lenses that are worse than many plastic lenses, but despite that I'd expect a glass lens to generally be better. Plastic does have one big advantage it's much easier to shape to accurate aspherical surfaces allowing a reduction in spherical aberrations, without very expensive elements.

    There are literally hundreds of types of glass, and loads of plastics too. The optical properties of each will be different. Good lens design requires the use of different materials where the properties are used to reduce the issues introduced by a simpler single material design. The classic example is combining crown glass & flint glass to reduce chromatic aberration.

    None of the lenses made for Lomography will be highly corrected (quite possibly all will be single elements as most of the lensbaby lenses are).
    Rather than relying on our prejudice have at look at Lomogrpahy groups on Flickr. this might give you a chance to access the results from both options & choose which YOU prefer. Esthetics are going to be more important than sharpness here. :)
     
    Last edited: Apr 20, 2017
  4. john.margetts

    john.margetts No longer a newbie, moving up!

    Joined:
    Dec 3, 2015
    Messages:
    1,103
    Likes Received:
    275
    Location:
    Lincoln
    Can others edit my Photos:
    Photos OK to edit
    As far the the initial question goes, both glass and plastic lenses work very well. My spectacles have excellent plastic lenses.

    Quality is a function of design and poorly designed glass lenses will not produce sharp images. You need to decide if Lomo lenses are going to be effectively designed or not.

    Sent from my A1-840 using Tapatalk
     
  5. webestang64

    webestang64 Been spending a lot of time on here!

    Joined:
    May 15, 2013
    Messages:
    1,854
    Likes Received:
    919
    Location:
    St. Louis, MO. USA
    Can others edit my Photos:
    Photos NOT OK to edit
    Lomo cameras/lenses will not be as sharp as say Nikon, Pentax etc.....glass or plastic it depends on the manufacture. When Kodak went to plastic lenses in their disposable cameras I saw no loss in sharpness.
     
  6. SoulfulRecover

    SoulfulRecover TPF Supporters Supporting Member

    Joined:
    Jun 8, 2010
    Messages:
    1,525
    Likes Received:
    724
    Location:
    Texas
    Can others edit my Photos:
    Photos OK to edit
    I have a couple Polaroid Land Cameras that have plastic lenses and they do great. I think it has more to do with the film than the lens. Lomo and Fuji instant film is not very good compared to to Fuji's peel apart film. Maybe Im missing something though
     
  7. smarty62

    smarty62 TPF Noob!

    Joined:
    Jun 25, 2017
    Messages:
    40
    Likes Received:
    43
    Lomo is about fun... not sharpness as other folks said before. Glass isnt't always sharper.... (see cheap old M42 lenses ), but compared to an old Nikon, Zeiss, Canon etc glass, glass is always better. Just my 2 cents.
     
  8. Dave Colangelo

    Dave Colangelo No longer a newbie, moving up!

    Joined:
    Apr 27, 2016
    Messages:
    452
    Likes Received:
    157
    Can others edit my Photos:
    Photos NOT OK to edit
    Lomo is about fun, soft focus, blurry edges, light leaks etc. But you pose an interesting question, you may want to read Ken Rockwells overly sarcastic article on sharpness here but ill throw in my 2 pence for every ones fun reading. First off good non glass lenses may very well yield better images than a poorly made glass lens how ever on the spectrum of whats practically commercially available glass lenses usually take the cake. Why that is has to do with a few factors.
    1. Glass making has been going on for far longer than clear precision plastic production. With that in mind we are just really really good at making flaw free glass that is great for lenses.
    2. Plastic tends to be mass produced in often somewhat inconsistent (for optical precision) molds and the results can vary greatly. If care is taken accurate plastic can be made.
    3. Glass machining and production tolerances generally lead to much tighter standards both because we desire it and because the medium allows for it.
    You should check out this video on how lenses are made. Sharp or not its a lot of cool footage.

    FWIW Plexiglas has a very similar transmission rate to regular soda lime glass at about 92%. So they both let through about the same amount of stuff. The issue boils down then to production and manufacture. Glass can simply be cut and polished more precisely than plastic.
     
    Last edited: Jun 28, 2017
    • Like Like x 1
  9. Gary A.

    Gary A. Been spending a lot of time on here!

    Joined:
    Sep 17, 2014
    Messages:
    22,357
    Likes Received:
    7,532
    Location:
    Southern California
    Most plastic will scratch easier than most glass.
     
  10. unpopular

    unpopular Been spending a lot of time on here!

    Joined:
    May 17, 2011
    Messages:
    9,471
    Likes Received:
    1,994
    Location:
    Montana
    One thing people don't take into account is the fact that index of refraction in inversely proportional to wavelength, so you want a material that has relatively little variation in IOR across the visible spectrum. You also want higher IOR so that you can get thinner lenses.

    http://opticalengineering.spiedigitallibrary.org/data/journals/optice/23421/013003_1_3.png

    As you can see here, polycarbonate is a pretty bad choice, but polyoleofin(??) would make a very good choice, assuming that it has good transmission. Ikea uses PO foam as a structural plastic.
     
    • Informative Informative x 1
  11. nerwin

    nerwin Been spending a lot of time on here!

    Joined:
    Jan 31, 2015
    Messages:
    3,486
    Likes Received:
    1,435
    Location:
    Vermont


    Doesn't Nikon's 17-35 2.8 have a plastic element?
     

Share This Page