query: Why does some lenses have red focus points on their focus rings?
positive_passages.docid: 86838
positive_passages.text: What do the red values mean on the distance scale of a lens?
negative_passages.docid: 57013
negative_passages.text: What is the purpose of the red laser pointers some Borg have attached to their head?
negative_passages.docid: 104041
negative_passages.text: What does a lens hood do?
negative_passages.docid: 27692
negative_passages.text: Why do I need an add-on lens to take smartphone macro photos?
negative_passages.docid: 86784
negative_passages.text: What is a focusing rail?
negative_passages.docid: 94271
negative_passages.text: What is the reference plane used when the minimum focus distance is measured?
negative_passages.docid: 130570
negative_passages.text: Why can't my SLR autofocus on certain parts of a scene?
negative_passages.docid: 80777
negative_passages.text: Canon 700d - lens does not move when focusing?
negative_passages.docid: 62759
negative_passages.text: Why am I allowed to turn my focusing ring beyond infinity?
negative_passages.docid: 4389
negative_passages.text: How can a lens with a single focal length focus on more than one plane?
negative_passages.docid: 54122
negative_passages.text: Why does using a tilt-shift lens make things look miniature?
negative_passages.docid: 102058
negative_passages.text: Weird canon 17-55 f2.8 IS lens error
negative_passages.docid: 41934
negative_passages.text: How do zoom, magnification, and focal length relate?
negative_passages.docid: 34665
negative_passages.text: What image-quality characteristics make a lens good or bad?
negative_passages.docid: 75334
negative_passages.text: Why do Full Frame lenses and crop body lenses exhibit the same crop factor when used on a crop body camera?
negative_passages.docid: 135594
negative_passages.text: Spotlight with Halo applied is creating rings around light
negative_passages.docid: 79654
negative_passages.text: What is the effect of the number of cross-type focus points on sharp focus?