Kevin asked in Consumer ElectronicsCameras · 9 years ago

How can you tell if a camera lenses is good or bad?

Other than the obvious stuff, like the size of the aperture and the zoom. What does it mean to have 11 elements and 9 groups? Is more necessarily better? People say that image quality is mostly dependent on the quality of lenses.

For example, which lenses is better?

http://www.dpreview.com/products/compare/side-by-s...

Update:

Taylor, regardless that they are not compatible with each other without an adapter, which one will give the better picture?

7 Answers

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  • Taylor
    Lv 7
    9 years ago
    Favorite Answer

    A general rule of lenses is cheap lens = crap lens. There are a few exceptions to this rule, two being Canon and Nikons 50 1.8s. The Samsung lens you listed is a Pentax mount but the other is a Canon... There is a newer version of the Canon 100 macro. When stopped down, they're both sharp. The newer Canon 100 macro probably has a slight advantage.

  • 9 years ago

    In order:

    1. Assuming the lens is manufactured to factory specifications (not damaged), years of experience using various lenses to develop an eye for superior image quality and personal taste.

    2. 11 individual pieces of glass, 9 separate groups (where a group can be one or more lenses making physical contact). One lone element = one group. Two elements touching = one group. Three elements touching = one group. Two elements touching and one not touching any other element = two groups.

    3. No. Some lenses have fewer elements are superior resolution/contrast/color. I would take a Zeiss 2/35 T*Distagon over a Sigma 28mm f/1.8 EX DG any day, but the Sigma has more elements.

    4. Image quality is mostly dependent upon the person holding the camera. Beyond that, image quality is very complex, involves many important factors in both equipment and subject, and cannot be easily broken down into a false dichotomy of lens vs camera. Ideally, both lens and camera should work as a seamless system with neither suffering from serious detriment in quality or craftsmanship.

    5. At this caliber of lens, either would be distinguished by subtle variations in contrast and color palette, as well as mechanical considerations. These are all subjective tastes, and as both are optically sound, there is no objective "Better." Both are macro lenses, both are from reputable companies. The Samsung is a Schneider rebrand, or vice-versa. The Canon is widely accepted as a quality lens. I have never found a true macro lens (I define as at least 1:2 magnification prime lens) that is not optically superb.

  • Scott
    Lv 7
    9 years ago

    Regardless that they work in different cameras, you are right, aperture and focal length are equal. So the next thing to look at is lens performance. Some reviews can be found where a standard grid target is photographed to map any displacement of the image, and likewise there are standard targets for sharpness.

    Beyond that, lenses like the very nice Canon (which I do own) are consistent enough that better photo editing software includes "profiles" for perfecting the small errors a lens might have, I did not check, but especially since this particular Samsung lens is not in production, AND a non-pro brand, I'd bet it does not have an Adobe profile (a 3rd party may have built one though).

    Then there is customer service, repair, and overall durability.

    One HUGE benefit with a prime lens, it that better ones do not pump air (and dust/moisture) in and out like most zoom lenses do. The Canon is internally focused = no air movement. The Samsung's objective (front) lens moves in and out as focus is adjusted = might just as well have a bellows blowing air (and dust/moisture, lol) into the lens and camera.

    I'd leave Samsung to make cell phones, if you want to save a buck on a lens, go used. Just take your time, be suspicious, and at least the first few, try to stick with local buys (craigslist). If you do use the mail, be sure you know the sellers return policy and promptly test any lens you get. Most of my lenses including the 100mm macro are used and I have never had a problem. (Paid $400 for the $600 lens).

  • Nahum
    Lv 7
    9 years ago

    Until you come to understand what all the different specifications mean, ignore them. Most of it is just "marketing", cheap words to entice you to a purchase. Actual performance comparisons (like the test shots that Scott mentions) give you a better indication than any stat ever will. Better glass also happens to be more expensive.

    However, two particular stats do prove useful:

    - A larger 'lens diameter' (which also roughly corresponds with the filter diameter) generally indicates better performance, since manufacturing defects on the glass will not affect the image as much as it would with smaller lenses.

    - A larger 'maximum aperture' indicates that it will perform better in low light. Also, when fully open, more of the lens glass is actually being used, which means all that glass has to be in top shape or defects will be noticeable.

    If you must know, an 'element' is an individual lens. 'Lenses' are actually composed of many lens elements, each of which bends light in a different way at different points along the light path. Some elements are termed "aspherical" (harder to produce than regular spherical elements) or "low dispersion" (uses exotic materials that reduce aberrations) that increase quality and price. A group of elements usually implies that they are cemented together and move in unison. Generally, the more elements, the higher the quality, higher price from ensuring the elements move properly, and higher susceptibility to shock or failure. (All moving parts and chemicals eventually fail, without proper maintenance.)

    Regarding your additional question: You simply cannot compare the two lenses. Even if they gave comparable performance, the fact that you have to use different camera bodies (from different brands) means you are going to get different performance.

    Also, don't bother with lens mount adapters. Most of the time you sacrifice other vital features like autofocus and metering, and the quality of the lens is now compromised by a potentially cheap adapter. Always go with the native mount.

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  • Anonymous
    9 years ago

    First you have to have a need, for a particular type of photography.Say macro work. Then check your manufacturers web site for the lens or lenses that best fit your needs. Then read all the comments by actual owners of this lens. Then check several sites like B&H or Adorama, or amazon. Also check what owners have to say. Match up the site with your needs and price. Buy the lens, making sure you can return it, just as you received it, with box and all packing materials, even original shipping box.Then take some pictures the same day you receive the lens. Blow one shot up to 11x14 to test quality.If it is great, keep the lens. Otherwise return it. Sites like dpreview. com will aid you in your decision making also.

    Source(s): 45 yrs professional photographer
  • Anonymous
    9 years ago

    I think bad.

  • Anonymous
    9 years ago

    should be good.

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