How could I achieve stock quality sharpness?

Question

I am using Canon 600d equipped with 18-55mm kit lens and also I bought 50mm 1.8. I am trying to take pin sharp pictures to upload them for sale.I am shooting still objects and models time to time. I shoot at Raw for post production. Using sturdy tripod, cable release and even mirror lock up if its necessary. I don't use anything but natural light for my pictures so shutter speed is an issue.

I wonder if the low shutter speed is my problem or cheap quality lens limitation. I might overreact and expect too much from my lenses but still my photos have to be sharp for sale and I would like to achieve pin sharp photos while shooting not after editing.

Thank you very much.

Heres a photo that I've taken. Bit sharpened and edited but gives idea.

http://www.flickr.com/photos/96728198@N04/with/8895052468/

Answer 1

For sharp images, you need the right combination of:

• Focus
• Aperture
• Shutter speed
• Lens

the first three are critical, it makes no difference what lens you have without the first 3.

-Focus: your focus point must be exactly where you want focus to be. Do not 'focus and recompose', meaning getting focus then moving the camera to compose the shot. Instead, compose then choose the appropriate focus point in your camera. You may need to test your camera/lens combination for accurate focus. Look here for instructions.

-Aperture: aperture is critical to good focus, because it impacts the depth of field and the circle of confusion. What this means is that as you open the aperture of your lens (say f3.5), the depth of what is in focus gets shorter. If you have a small aperture (f16) more depth is in focus at one time. An example is if you focus on a model's nose, with a wide aperture, often that model's eyes will be out of focus. Get to know and use a DOF chart.

-Shutter speed: This is less of an issue with a tripod, but shutter speed is critical for sharp focus because any camera shake can cause blurring. Generally, it is recommended to use a tripod for speeds less than 1/60, or 1/ your focal length (if shooting a 500mm lens, you need a speed of 1/500 or greater to eliminate shake from hand holding the camera). If your subject is moving, you need to increase the shutter speed to reduce blurring from subject motion. If you are shooting multi-second exposures, you can sometimes see blurring from the movement of the mirror, though that can also mean you have a bad tripod.

-Lens: if you have mastered all of the above, and still don't have sharp images, then your lens is to blame. The difference in image sharpness between a professional ("L") Canon lens and a kit lens can be shockingly amazing. However, note that this sharpness is usually only really apparent when zooming into the image. Sharp images look good at every perspective, but pixel peepers are really those that zoom in 100% during post editing, and declare whether a lens is truly 'sharp'. Get a new lens only when you have eliminated 1-3 above.

Answer 2

You kit lens is to toss. Your 50mm prime is pretty sharp. but...

If you are judging the sharpness at pixel peeping range (100% size view) you are also expecting too much of your camera. Being a crop sensor and having a anti alias filter, you simply cannot get sharp images, unless you rescale to screen size with output sharpening (don't let your image viewer to the rescale on the fly). your lenses have a certain real-world resolution that is worse than needed for your sensor pixel size. Those striking large , super sharp and detailed photos you see around on advertisements and film posters, are from medium-large format cameras, using lenses more expensive than you entire camera gear together, and heavily processed.

Answer 3

Shutter speed is only a limitation if the camera or anything in the frame is moving. If both the scene and the camera are static, then the problem lies elsewhere. Having said that, realize that just because the camera is mounted on a tripod does not mean the camera is motionless. It all depends on how stable the tripod, the head, and what the tripod is resting on are. Mirror lockup is very useful when using a tripod and shutter speeds in the range of around 1/80 to 2 or 3 seconds. Exposures longer than that aren't as affected by the vibration caused when the mirror swings up because the vibration stops after a few fractions of a second and the camera is no longer vibrating for most of the shot.

For critical focusing, manual focus done properly will always be more accurate than Phase Detection Auto Focus (PDAF). So will Contrast Detection Auto Focus (CDAF). Neither are as fast as PDAF. See Roger Cicala's blog entry and realize all the tests were performed with a very sharp, modern lens with partial closed-loop feedback capability. The variation from shot to shot using PDAF is significant.

Most lenses are not at their sharpest at maximum aperture. This is especially true of the EF 50mm f/1.8 II. It performs much better in terms of sharpness stopped down to f/2.8 or narrower. Due to the five blade aperture, bokeh is an entirely different matter. On the other end at narrower apertures, diffraction comes into play. The Diffraction Limited Aperture (DLA) for your 60D is f/6.9. This is the point at which the blur circle for point light sources at the point of focus will be larger than the size of your camera's sensor pixels. It doesn't mean you should never use apertures beyond the DLA, but you will not get razor sharp images when pixel-peeping at 100% if you go beyond the DLA.

Looking at your photostream on Flickr, you are getting good results for your current gear. I examined the photo and EXIF info for the clock in detail and here is what I would encourage you to try with a still life subject such as that:

• Shoot from a tripod and save your files in RAW format.
• Focus manually. Use Live view at 10x magnification to set the focus.
• Use a narrower aperture. Somewhere around f/5.6. If you want the narrow DoF of f/2 or wider so that part of the clock is blurred, you need a better lens. Also, if using a narrower DoF, turn the clock so that the face is parallel to the sensor plane. The reason the right side is more in focus than the left is because the left side is further from the camera.
• With the narrower aperture, you will need to use a longer shutter speed. This will actually help reduce the effect of vibrations from shutter movement.
• Either use mirror lockup or shoot the photo from Live View, since the mirror is already up in Live view. Allow a few seconds for everything to stabilize after you have touched the camera and the mirror is locked up.
• Use a remote cable release.
• If using a shutter speed longer than one second, enable Long exposure noise reduction. Even at ISO 100.
• Even with high quality lenses, using Canon's Digital Lens Optimizer inside their Digital Photo Professional software can make a significant improvement on the overall sharpness of an image, especially one with diffraction or chromatic aberration. No one else has as much knowledge of the design and characteristics of Canon's lenses and bodies as Canon does. Using DLO will double the size of the RAW file, and since other applications will only read the original part of the file, if you want to do further processing with an application other than DPP you will need to export the image as a 16bit TIFF, which increases the file size even more.

Answer 4

If you are shooting with a tripod with a still subject, then shutter speed shouldn't be a problem. The problem is the kit lens. Kit lenses in general are rarely good. If you want to take sharp photographs you will need a sharp lens. If you have complete control over your shooting environment, then the cheapest way to get sharp lenses would likely be to get a few good fast primes.

Answer 5

You may want to consider upgrading your lens as there are some awesome "L series" lenses on the market which deliver stellar optics.

You may wish to:

• Use RAW (to increase the pixel density)
• Use a tripod or image stabilization (where applicable)
• Adjust the shutter speed
• Use flash

I hope that helps!