LENSES ON DIGITAL CAMERAS
General Information:
Digital SLR cameras electronically capture images using a method similar to that of film. In place of film, an image capturing device is used and is generally called a CCD (Charged Couple Device) or CMOS (Complimentary Metal Oxide Semiconductor). Since the CCD or CMOS is usually smaller than a full frame of 35mm film, the focal length of any lens is effectively increased, usually by a multiplication factor averaging about 1.55x (most Canon models have a 1.6x factor while Fuji FinePix Pro and most Nikon's have a 1.5x factor).This holds true unless a 35mm full frame image capturing device is used. For example, a 14mm lens would be considered an ultra-wide angle on a conventional 35mm camera or full-frame digital camera, but it would be equivalent to about a 21mm on most digital SLRs using the smaller image capturing device. The same is true for zoom lenses as well; for example, a 17-35mm lens on a conventional 35mm camera is approximately a 26-54mm when used on a digital SLR.
Auto Focus Performance and Image Quality:
When using a digital camera it is very easy to choose a specific area, magnify it, and check it on a computer monitor. If this area is excessively magnified beyond the normal viewing capability, the image will appear pixilated. For example, viewing an image on an average 17-inch monitor with a pixel count of 6,000,000 is like viewing a film print at approximately 32x21”. Under these conditions, it is possible that slight auto focus errors will be visible that would normally go unnoticed on a normal size print or enlargement.
Auto Focus technology has been around for many years and has improved dramatically since its inception; however, under certain conditions it can get confused. The best focus point may shift slightly when certain conditions exist such as a low lighting on the subject matter, low contrast, etc. This can occur with both film and digital cameras.
Tamron SP Lenses: (Super Performance)
Many photographers, amateur and professional, are using Tamron’s SP lenses on their digital SLRs. The SP series of lenses feature outstanding optical performance based on demanding design specifications. In designing any SP lens, the first and foremost priority is given to high optical performance and superior specifications. When using an SP lens on a digital SLR, we recommend that you shoot test images, consider the findings, and confirm satisfactory performance.
Tamron Di Lenses: (Digitally Integrated; a new standard of lenses for Film and Digital SLR Cameras)
Di design is the designation Tamron puts on lenses featuring optical systems designed to meet the performance characteristics of Digital SLR cameras currently on the market.
For specifications on our Di lenses, please click here.
Tamron Di II Lenses: (Lenses designed Exclusively for Digital SLR Cameras)
Di-II inherits all of the optical benefits of the Di design. Di-II lenses are made for exclusive use on digital cameras with image sensors 24mm x 16mm and smaller and are not intended for use on full-frame D-SLRs or film cameras.
For specifications on our Di lenses, please click here.
Tamron’s Warranty Policy:
Like all Tamron lenses, our SP and Di lenses come with a manufacturer’s 6-year limited warranty.
Contact Information:
If you have questions about the use of your Tamron lens on your digital SLR camera, please contact our service department at 631-858-8400 ext. 2502, or via e-mail at custserv@tamron.com. |
