During the 1960s to early 80s every optical house had Super Panchro type, then Super Takumar type Double Gauss normal lenses jockeying for sales.
22.
It provides a field of view on a DX format camera similar to that of a normal lens on a 35mm film format camera.
23.
Especially outside of the " normal lenses ", lens speed also tends to correlate with the price and / or quality of the lens.
24.
For normal lens, field of view can be calculated FOV = 2 arctan ( SensorSize / 2f ), where " f " is focal length.
25.
That's more than contacts that change eye color ( about $ 110 ) as well as normal lenses ( about $ 90 ), according to Nitschke.
26.
The apparent difference in proportions results solely from the content added around the edges of the frame in the normal lens photo and the wide-angle photo.
27.
Although the wearer ideally should be able to tell no difference from a normal lens, Travis and Tiffany complained that some of the styles altered their vision slightly.
28.
By comparison, the " Rolleiflex " only had a single, fixed normal lens, although the Rollei " Magnar " tele-converter lens with 4x magnification was available as an accessory.
29.
The Double Gauss became the preferred normal lens design in the 1950s with the availability of antireflection coating and new generation extra high refractive index rare earth optical glasses.
30.
The introductory US list price for the body plus normal lens was only $ 231 note that SLRs usually sold for 30 to 40 percent below list price.
