Camera V.S Len Quality

[xxWesxx]

Okay, so when i get my image from my Cannon Rebel T3i. I notice that the images aren't as high quality. As in there is some grain, and some small blurs. Even with a Still shot, it still is grainy and blurry. Now my question is.. Would My Cannon Rebel t3i be the problem with quality? Or would the 18-55mm Lens be the problem? If so, what kinda body should i be looking into, for a very clear and crisp picture? As in, when i zoom in a little, its all nice and clear, and not pix-elated. Or What kinda lens should i be looking into that is a prime lens, and can take some Portraits? Recommendations?


Now this was done with a 18-55MM Kit Lens from cannon.
Shot in RAW.

 

[Scatterbrained]

If it looks pixelated you're zooming in too far.

 

[Scatterbrained]

Things to remember: Images will need sharpening in post. If you shoot jpeg the camera will apply the sharpening. You can adjust the sharpening level in the cameras picture style settings or you can create a custom setting using the Picture Style Editor that comes bundled with the camera. Bear in mind that if you are shooting raw and editing in Digital Photo Professional the in camera picture style will be the starting point. DPP is the only raw converter that can read the picture styles. If you are editing in something else you've have to determine the appropriate level of sharpening to apply yourself. Digital sensors have anti aliasing filters over them to help prevent aliasing and moire, the do that by softening the images so a bit of sharpening in post is a requisite.

Without Exif I don't know your shot settings, but it bears reminding that diffraction can have a negative effect on image sharpness. Stopping the lens down too far can lead to diffraction which will cause a loss of sharpness. Cheap filters on the lens can also cause image softness. If you have a filter on the lens just go ahead and take it off. Stopped down the kit lens should be plenty sharp. Sure, it's not as sharp as something like the 85L II, but when the focus is on it should be just fine.

 

[Overread]

The are a few factors:

1) User error.

2) Lighting quality

3) Lens quality

4) Camera body quality

And its roughly in that order of importance.

First you have user error; under exposing and them bumping up the exposure will show more noise; a higher ISO but a good exposure (look up the expose to the right theory) will give less noise than a lower ISO and a more underexposed photo. Using the right aperture for depth of field, as well as the right shutter speed to eliminate motion blur (remember wind makes things move even if all else is static - and if you're hand holding you need good posture and at least a shutter speed of 1/focal length or faster).
Then there is aperture selection; no lens is its sharpest wide open (smallest f number/biggest aperture) and thus using a wide aperture can mean that you end up with softer photos. Apertures like f8 though render things much sharper overall. This is the bonus of many of those wide aperture primes - not only are they very good wide open, but you can close them down a little (ergo not all the way to f8) and get improved sharpness.

Then you've got lighting, lighting is very important. In the shot above you've got very strong light in a very high position which is casting some very strong shadows - in the eye crop you're clearly losing the eye and its details to that heavy shadow cast by the eyelid and head. Good lighting control can eliminate this problem. That might be using a reflector to bounce some sunlight into the shadowed regions or it could be the use of one or more flash units to provide fill lighting.

Then there is the lens, the lens focuses the light and as such has the greatest effect (all else being equal and correct) on elements such as sharpness, detail and clarity. A good lens will render a sharper shot and typically retain more fine detail. However remember the point about aperture being important in this as well - an f8 even from a modest kit lens on todays market is going to be generally pretty darn good.

Finally there is the camera body and this really only comes into play seriously when it comes to very low light and thus a demand for high ISO values.



that is a very rough assessment; there is more to it than what I've said. However it should give you a rough idea that the camera body is likely not the most critical bit of the puzzle at this stage. Your capacity to use the camera- your lighting and your lens are going to be generally higher priorities before you need to think about the body.

 

[Overread]

Note with 18MP camera sensors I find that 60% view is about the best to judge sharpness. At 100% things do look softer because you've blown the image up to a huge size to view it - yes it shows details, but its so big that even a very sharp setup is starting to be pushed toward the limits. I view at 100% to adjust sharpening and noise settings, but I view at 60% to judge sharp keepers with my photos (part of that though is because I started on a 400D which hada much smaller MP rating and thus I got "used" to the clarity it showed - more MP means that 100% view gets bigger and on 18mp sensors I'm just not used to seeing their 100% - you might find even without prior experience that this proves true for you as well).

 

[Derrel]

With a Rebel T3i, properly-exposed images shot in RAW mode in good springtime and summertime weather during the day ought to have VERY fine image quality, even with just the 18-55mm kit zoom lens. If the images look sub-standard, it might be that you're doing something improperly. As overread mentioned, viewing 18 MP images at full, 100%-pixel size (ie, zoomed in so the image is at "100%" magnification) will show every single bit of noise and detail, so, that's not really the best way to view images, scrolling around, looking at small segments of a five-foot-tall image!

It's also possible, since the images are so,so big these days, that your computer is actually where the issue lies--and that it is RE-SIZING the images, making them much smaller, and that the re-sizeing process is causing some weird artefacts to appear on-screen.

 

[CdTSnap]

That image looks ok to me? I wouldnt expect much more from that combo?? Looks to be in focus.

 

[hotdrop]

The image looks fine, its not a good picture of your subject, its a bit overexposed, and your choice of lighting does not work well with your subjects skin tone. Your limiting factor is not the camera or lens in this photo.