What's so special about Groups and Elements

Horoscope Fish

Senior Member
WHY do I need to know how many Groups and Elements there are in a lens?
You don't need to know; it amounts to superfluous information. You seem bound and determined to attribute significance to this technical specification; why I don't know, but there simply is none.


Does a lens with 9 elements in 5 groups perform better or worse than a similar lens with 8 elements in 6 groups?
Overall lens performance has nothing to do with the number of groups/elements present in the lens. The two things are entirely independent of one another. I'm not really sure how else to put this.


What does this information mean to me?
Nothing.


... I was under the assumption that the fictional trade names of FlareMaster and PurpleFinger would be a huge tip-off that the lens doesn't exist.
Now I'm just disappointed.

...
 

Dave_W

The Dude
The group/element listing is for those optic wizards who love the physics of light and find meaning in the nuances of lens engineering. To common users, it means nothing. Same with listing the chemical name and structure on the side of medicine bottles. It's there only for us medchem geeks and no one expects the common user to care one way or the other

Sent from my SCH-I535 using Tapatalk
 

SkvLTD

Senior Member
OK, maybe it's time to rephrase the question.


I'm shopping for a new 50mm f/0.45 lens. I've narrowed down my choices to the FlareMaster and the PurpleFringer. Both are 50/0.45s, they're the same size & weight, take the same size filters, etc. Setting them side-by-side, they appear identical. But the FlareMaster has 9 elements in 5 groups, and the PurpleFringer has 8 elements in 6 groups.

Which one should I choose, and why?

Like shopping for cars. You can buy car A or B and the only differences between them is auto/manual transmission and front/rear wheel drive. IF you have NO idea what the technical difference is and thus have no particular preference, it's really all the same to you. Both cars will let you drive from point to point about equally the same unless you can make use of their differences.

My own personal example,
Nikkor-H 50/2: 6 elements in 4 groups
Nikkor 45/2.8 AI-P: 4 elements in 3 groups

Say aperture is the same, difference in blades is negligible, etc etc. Since the original 45/2.8 wasn't too far from the 50 H, let's say that their technological level is about the same as well (since other equally thin lenses have come out since with much more complex designs).

It all comes down to how light passes through all that glass: how prone it is to flare and how the flare looks; whether corners are sharp or softer; and then we have physical size and weight. Another factor could be ability to focus closer than the competitors and that's all governed by the internal design.


I, won't ask how you're semi-pro in experience without knowing these kinds of basics since I know quite a few people who can make really nice pictures with the sole knowledge that shutter buttons makes the picture happen using camera with some lens attached.
 

SkvLTD

Senior Member
Overall lens performance has nothing to do with the number of groups/elements present in the lens. The two things are entirely independent of one another. I'm not really sure how else to put this.

Am I really reading something like this from you, of all people? :/
 

SkvLTD

Senior Member
MY final statement is this- whoever thinks that our Nikkor 105/2.8 and say, Trioplan 100/2.8 are "practically the same" has a big research paper due by the end of the week. Late submissions not accepted.
 

WayneF

Senior Member
Am I really reading something like this from you, of all people? :/

Yes, that certainly was a puzzler why anyone would say that. The intended meaning must be different than the words chosen.

It may not matter to us why the f/2.8 zoom has 18 elements in 14 groups, we know nothing about such details... but it was very important to the performance designers who found it necessary.
 

SkvLTD

Senior Member
Yes, that certainly was a puzzler why anyone would say that. The intended meaning must be different than the words chosen.

It may not matter to us why the f/2.8 zoom has 18 elements in 14 groups, we know nothing about such details... but it was very important to the performance designers who found it necessary.

Read my post right above yours. Google.
 
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