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41

This is a Sigma name for one of their lens lines. It is not a general purpose term and really only has the marketing meaning Sigma ascribes to it. From the Sigma website, that definition is: Engineered for today’s photographer who wants to do it all, our Contemporary line combines superior optical performance and compactness for high-performance lenses ...


27

Because that rainbow is partially obscured by your subject, I would tend to believe that it has nothing to do with any of your equipment. Rather, there was something in the room acting as a prism and diffracting light into a rainbow pattern that just happened to fall within the frame of what you were shooting. It might be that the source of the light was ...


25

Your old D80 had a focus motor built into the body that connects to a mechanical coupling on Nikkor AF lenses to move the focus elements in the lens. Your D5300 does not have a focus motor in the body. To use autofocus your D5300 requires that you use Nikon AF-S or AF-I lenses or the equivalent third party lenses (such as Sigma's HSM or Tamron's USD and PZD ...


22

I think you are putting too much emphasis on the "digital" part of the lens' DG designation. It seems to be more to differentiate them from "digital" lenses that are APS-C only. Sigma calls their current APS-C only lenses "DC". When digital SLRs first began to gain a foothold in the market, they almost all had sensors that were APS-C or similar sized. So new ...


18

Yes, lenses designed for digital sensors have several differences from their older film based camera lens counterparts. One of the primary differences is that digital sensors are more reflective than film, so anti-reflective coatings are applied to the rear element of a digital lens. This helps prevent reflections off the sensor that could result in image ...


15

Based on your comment, you have a Sigma 17-70mm f/2.8-4 DC Macro OS HSM Lens, which is an APS-C lens, on a full-frame camera. An APS-C sensor is smaller than a full-frame sensor, so the lenses that are designed for these cameras project a smaller image circle. APS-C specific lenses aren't designed to be used with with full-frame cameras. (See this post for a ...


15

It is a common problem when using some 3rd party lenses. Just turn off the in-camera lens corrections.


9

I think you've got a Minolta A-mount lens. Compare to this photo (image borrowed from here): Minolta and Konica merged at some point and were subsequently acquired by Sony, and this mount is apparently still used by Sony as the "Alpha mount system".


9

You are apparently using a Sigma DC lens on the full frame Canon EOS 6D. Sigma DC lenses are designed to be used on "crop body" cameras. That is, cameras with APS-C or smaller sensors. APS-C sensors are 24x16mm or smaller. SIgma DC lenses only need project an image circle large enough to cover an area 24x16mm with a diagonal measurement of just under 29mm. ...


8

The Sigma dock only works with select Sigma lenses. The lens needs to have the needed firmware to respond to the commands sent by the dock. Even Sigma lenses that are not part of their 'Global Vision' selection (ART, Sports, Contemporary) can not be calibrated using the Sigma USB dock. So how i.e. does Sony 100mm lens for E-mount is calibrated? Is is ...


7

You don't really need the dock until you need to install a firmware update, or until you decide you want to fine tune the lens. My suggestion: don't buy the dock until either of those situations arise. No need to spend the money now because you might want to do something later. You can also rent the docks from some of the lens rental places (lensrental.com ...


7

Is there a reason why Canon and Nikon allow third party makers to make lens that provide similar specs to first-party lens such are AF, IS and aperture control when they sell for less? Controlling a product line that has the support of many third parties is much more profitable than trying to build and sell every product yourself. Canon and Nikon don't just ...


7

This is probably because some cameras disable autofocus at slow apertures. The camera manufacturers think that performance won't be good enough, and so they disable it. The third-party lens is reporting inaccurate information to the camera so that it will work anyway — slow and sometimes incorrect, perhaps, but at least the camera will try. Exposure might ...


6

There is one significant difference between film and digital sensor for lens optics - digital sensors have a bit of glass and some filters in front of them. The lensrental.com blog has a pretty extensive series of posts on the effect of the sensor stack (short version, there is a very real effect for large aperture lenses) - so it is quite possible that the ...


6

Some 'film' lenses designed for 35mm rangefinder cameras have a rear element which lies quite close to the plane of the film or sensor (mostly wide-angle lenses). These work fine for film, but when used on a digital camera cause quite noticeable colour shifts to the left and right of the frame. This is due to the extreme angle of the light from the rear ...


6

Neither of those lenses are really what most macro specialists would consider a macro lens. For a lens to be considered a true macro lens it should be able to project a life sized image of the subject onto the image sensor or film. If you're taking a picture of a 20mm long bug, a macro lens should be able to focus close enough to project an image of the bug ...


6

The first sample image in the question is focused well in front of the central pillar. The second is focused well behind the flowers. You have told us that you are using single point AF but you haven't told us which AF mode you are using: One Shot, AI Servo, or AI Focus? If you're trying to focus and recompose using AI Servo the camera will refocus when you ...


6

Nikon doesn't tell Sigma how their TTL protocol works (and Sigma does not pay to license it). The communication is reverse engineered. Sometimes, the protocol used varies slightly from camera body model to model — and sometimes, that variation means that the guesses Sigma made are out-of-spec and communication breaks. Sometimes, Sigma updates the firmware of ...


6

It sounds like your Sigma 24-70 has sticking aperture blades. If it happens only intermittently, you can try and free them up. Select a small aperture like f/22 and use your depth of field preview button to open and close the aperture blades rapidly. I have an old Canon 28-70mm f/3.5-4.5 from 1989 that used to do this. I didn’t really use this lens much, ...


6

However, if I understand correctly the aperture need to be multiplied as well, which results in an f2.1 and means I am losing at least an f-stop. In short: No. If you use a FF-lens with an APS-C sensor, part of the light that is collected by the lens is not hitting the sensor but the amount of light that hits a part of the sensor stays the same (as long as ...


6

Yes, DG lens serie from Sigma are compatible with fullframe cameras. About the effect seems like you enable in-camera lens correction. And this correct do not work well with 3th party lenses. Check page 200 of the manual of camera and switch off this correction


5

This photo is severely back focused. Areas about 15-20 feet behind the main subjects are in focus. Some things to keep in mind: When using wider apertures, especially combined with larger sensors, Depth of Field becomes shallower. So any focusing errors are more apparent. This is especially a problem in low light when most camera's auto focusing systems ...


5

It depends. The Canon flashes you listed in your question use pulsed light from the Master unit to tell the Slave units when to fire and how much power to emit. This allows proprietary communication between the Master and Slave units and allows for use of Canon's E-TTL automatic exposure system as well as permits the photographer to set manual power levels ...


5

Any teleconverter/extender made for the Canon EF mount will work with your camera. Your question should be, "Which teleconverter would work with my lens." The short answer: It depends on what you consider as "working." You'll probably think, "No." Here are the main reasons why: You lose maximum aperture and thus auto focus. A 1.4X converter costs you one ...


5

It's possible the lens is miscommunicating with your camera. If the camera's Auto DX crop setting (under Shooting Menu > Image area) is set to "On", and if somehow your camera is interpreting the lens as a crop lens, then it will automatically crop the center of the sensor when it takes images, and will draw the DX crop reticle you see in the viewfinder. ...


5

Most/some third-party lenses report better apertures than they actually have - e.g. with f/6.3, the Sigma 150-600mm f5-6.3 Contemporary DG OS HSM would no longer work with phase-detection-AF (or, to be more exact, the 1300D, as most entry- and mid-range-models, would deactivate PDAF) : [If] the maximum aperture becomes higher than f/5.6, AF shooting will ...


5

All three of these lenses are older designs from almost thirty years ago at the infancy of the autofocus era that gave birth to the Canon EOS platform. With lenses in the same basic class that are this old, the condition of each individual copy is probably more impactful than the differences between each lens design on paper. The difference today between ...


5

You will never lose any transmission stops (low light ability) using a smaller sensor, unless something behind the camera mount severely constrains what reaches the sensor (unlikely with general purpose still cameras one sensor size apart). Some would say ISO at different sensor sizes is not equivalent: When exposure is discussed, this is nonsense; such ...


5

This is a known issue when using certain third party lenses with certain Canon cameras that have in camera lens correction enabled. It seems almost totally random which camera and lens combinations demonstrate the issue and which ones do not. As Roger Cicala says in the linked blog entry, some lenses work with some cameras but not others. At the same time ...


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