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2 votes
1 answer
3k views

What does "Di III" in a Tamron lens model name mean?

A Tamron "Di" (Digitally Integrated) lens is a lens optimized for digital cameras including those with 36x24mm 'full frame' sensors. A Tamron "Di II" (Digitally Integrated II) lens is a lens ...
  • 170k
7 votes
1 answer
5k views

What are STF lenses?

What are STF (smooth transition focus) lenses? How much do they differ from other fast lenses? What artistic techniques are done with them? For example Sony has an a-mount 135mm F2.8 [T4.5] STF. What ...
-1 votes
2 answers
145 views

How much zoom does a lens need to have before we call it a superzoom lens?

I've read that superzoom lenses have poor image quality, but how much zoom does a lens need to have before we call it a superzoom lens? 3x is certainly not a superzoom, while 10x probably is. ...
10 votes
5 answers
126k views

What is the difference between Nikkor D type and G type lenses?

I recently bought a Nikon D5100. And along with this camera, I got the AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR lens as kit. It's "G" type lens, right? One of my friend suggested to buy a 50mm f/1.8D ...
  • 203
4 votes
3 answers
45k views

What is the relationship between "macro" and "telephoto" lenses? [duplicate]

Can anyone explain the difference between "macro" and "telephoto"? I know that a macro lens will give you a magnification of 1:1 but how does it differ from a telephoto lens?
9 votes
2 answers
11k views

What does "Flat Field Focus" mean?

Looking at lenses, specifically sigma macro lenses, I noticed that it had a ""Flat Field" front lens element". What does this mean? And how is it different to the norm?
1 vote
1 answer
8k views

What are screw drive lenses?

Are lenses known as screw drivers actually available?If so what are their features and why are they called so.Name some of the lens and their manufactures.
  • 3,466
4 votes
1 answer
516 views

What is meant by 'centering quality'?

I'm reading lens reviews and I have encountered the term 'centering quality' a few times (e.g. http://www.photozone.de/sony_nex/720-sony50f18nex?start=1). What does this term mean? What are the ...
17 votes
2 answers
7k views

Retrofocus lens? What's that?

I saw that in Why do some people prefer 50mm to 35mm prime lenses, even for a crop sensor? , in @MattGrum's answer: ... The 50mm is a simpler design compared to the retrofocus 35mm ... What's ...
  • 1,285
0 votes
3 answers
2k views

Below which focal length are lenses considered to be wide angle?

Focal length is the only factor that decides whether a lens is described as being normal or wide angle. Below which focal length are lenses considered to be wide angle? Is this focal length the same ...
  • 3,466
9 votes
2 answers
9k views

What are ED elements?

I find that some lenses are indicated with the letters "ED", referring to some special type of lens element. What are ED elements, and what advantages do they bring? Note that this question isn't ...
  • 5,806
2 votes
1 answer
3k views

How does the quantity of elements and blades in a lens affect the optics?

I am trying to get a greater understanding of how lenses work. Basically I bought this lens, the Sigma 10-20 f4-5.6: The construction has really fascinated me. 14 Elements in 10 Groups?! What exactly ...
  • 2,561
43 votes
4 answers
42k views

What does the number of elements and groups in a lens mean?

All lens specifications include a statement of how many elements the lens contains, and in how many groups, for example: Nikon AF-S VR Zoom-NIKKOR 70-300 mm 1:4,5-5,6G: 17 elements in 12 groups (two ...
  • 1,285
11 votes
4 answers
5k views

Lens "family" names - what do they mean and should I care?

Some lens manufacturers have special names for their lens designs/families. Just to name a few: Leica - Summar/Summarit/Summilux, Elmar/Elmarit, Noctilux Carl Zeiss - Planar, Tessar, Sonnar, Distagon,...
  • 10.6k
31 votes
2 answers
7k views

What is a pancake lens?

I've read about a "pancake lens" but don't really understand what that means. What the pros and cons of having a pancake vs. another type of lens? I'm thinking of getting a Panasonic Lumix DMC-GF1 ...