What does "mm" mean in digital photography?
Does it refer to the length between the sensor and lens? How can I find out what the min and max distances are for my camera? Is this referencing the same "mm" as a 58mm filter add-on for my camera? If someone says that a lens isn't as good between 28 and 44mm, what does this mean in layman's terms? Sorry for all of the questions; any help is appreciated!
In layman's terms, it means the same thing that inch means. It is a unit of linear measure.
For instance the sensor may be 24 x 36 mm (the same as a 35 mm negative) or the lens my be 100 mm (a medium telephoto) or 12 mm (a very wide angle lens)
When lenses are tested under laboratory conditions, lab techs look for inconsistencies in lens performance like pincushion and barrel distortion as well as colour aberrations at the edges of the image. In the report, the mention these issues and tell the reader where these problems occur. Based upon these errors, a person can decide whether or not they want to buy a certain lens or not.
Most minor aberrations are tolerable, especially if the buyer is not attempting to make a living as a pro or in actual use, do not show up and detract from the image being photographed
Sometimes the maker of a lens actually designs in some of these qualities, like the Canon EF 135mm f/2.8 Soft focus lens used mostly for shooting portraits.
Digital Photography - Call me on Skype with your Photo Questions
digital photography questions5
digital photography questions5
No comments:
Post a Comment