What is the difference between DG and DC lenses?
The designation DG indicates that the lens has been optimised for digital SLRs but is equally compatible with film SLR cameras. These will work on digital SLRs with a small (APS-C size) image sensor, digital SLRs with a full frame sensor and film SLRs. DC lenses are designed specifically for digital SLRs with the small, APS-C size image sensor. These are not suited for full frame digital or film SLRs as heavy vignetting will occur.
There are many abbreviations used by SIGMA in the name of you, can you explain what these mean?
Each abbreviation has its own meaning and is an important part of the lens’ construction and design. Here you can find a list of abbreviation with their meaning.DG: Lens compatible with DSLR camera's with full-frame image sensors.DC: Lens is optimized for DSLR camera's with APS-C size image sensor.DG DN: Lens exclusively for mirrorless interchangeable lens cameras with full-frame sensorsDC DN: Lens exclusively for mirrorless interchangeable lens cameras with APS-C sensorsOS: An optical stabilizer mechanism built into the lens helps assure a sharp image while giving you freedom of movement and more latitude in camera settings.HSM: Using a motor driven by ultrasonic waves, these lenses offer speedy auto focusing and quiet operation.
I would like to purchase a new camera of another brand, is it possible to change the mount of my previous SIGMA lenses?
SIGMA produces lenses with exclusive fixed mount systems; therefore it is not possible to change the mount of a majority of SIGMA lenses. However with the new Mount Conversion Service, any of the Global Vision Lenses can be converted to a different mount system. More details can be found on the Mount Conversion Service page.
I understand SIGMA make 1.4X and 2X tele-converters. Do these converters work on all SIGMA lenses?econverter?
Our teleconverters are matched to work with a few SIGMA telephoto lenses and are therefore not compatible with all our lenses.
What is the difference between built-in HSM lens and DC-motor lens?
With conventional auto-focusing, auto-focus is driven by electromagnetic force of a DC-motor, gear and shaft mechanism. However, Ultrasonic Oscillation Energy operates the HSM lens and creates high-torque drive. Since this motor has no reduction gears, it has much quicker response to start and stop compared to DC- motor lenses. HSM system has virtually silent auto focus function, very quick responsive auto focus function and “full-time” manual focus, wherein AF can be overridden without disengaging the AF mode altogether.
I have just purchased a new Sigma optically stabalised lens and notice that the lens makes a slight noise when I half press the shutter button. Is that normal?
OS lenses do make a soft noise upon start up. This noise emits whilst the OS system is setting into position. Once the OS is set, generally after one or two seconds, the noise will stop. This is completely normal for OS lenses.
Is it possible to use the OS function with a tripod?
The vibration caused by the firing of the shutter and the movement of the mirror is transferred to the tripod. The characteristics of these movements are different to those experienced during hand held photography and the OS system cannot compensate for them. If you wish to use a tripod, please switch off the OS function..
You use the term ‘Minimum Focusing Distance’ on all your lens specifications. What does this mean?
This is the distance from the film plane/image sensor to the subject. Many people assume it is the distance from the front of the lens however it is measured from the film plane. The shorter the Minimum Focusing Distance, the closer you can focus on the subject.
Can I use different types of lens hoods on my SIGMA lens?
No. All our lens hoods are matched exactly to the lens they are supplied with.