How to Get Sharp Images

I’m often asked questions like “How do you get the amazing details in every shot?”. There is no magic involved but following a couple of guidelines will definitely help to improve the perceived sharpness of images.

1. Camera:

Use a high-resolution camera without an antialiasing filter (for example a Sony A7RII) and always shoot in RAW with the highest bit rate and lowest compression.

2. Lens:

Use a sharp lens with high micro-contrast (for example most of the Zeiss lenses).

3. Filters:

Either use no filters or only high-quality filters (I use B+W and Heliopan). Cheap filters will degrade image quality. If shooting against the sun it’s best to use no filters at all.

4. Aperture:

Use the aperture with the best compromise between DOF (depth of field) and not too much diffraction. I nearly always shoot at either f/5.6, f/8 or f/11. Know which apertures are sharpest for each individual lens. And always try to avoid stopping down beyond f/11, otherwise, you will lose all the fine details due to diffraction.

5. Exposure time:

Avoid critical exposure times if possible. When shooting from a tripod exposure times below 1/100 sec and above 1 sec are safer regarding motion blur than anything in between. If you have to shoot within this critical range of exposure times use the EFC (electronic first curtain shutter) to reduce the effects of shutter induced vibration. For shorter exposure times than 1/1000 sec EFC can have a negative effect on image quality (uneven exposure and bokeh impact, see here for more details). Therefore know when to switch it off.
When shooting handheld the old rule of using exposure times of 1/(focal length) or shorter is for modern high MP cameras only valid for image stabilized lenses. For non-stabilized lenses use an exposure time half as long or shorter (for example for a 100mm lens the longest exposure time for handheld shooting should be 1/250 sec).

6. Tripod:

Use a stable tripod and a stable ball head (in my case a Gitzo tripod with an Acratech head). Raise it only as far as necessary for the composition. The lower the tripod is extended the more stable it is. Avoid center columns on tripods (I only use tripods without center columns). Put the tripod on a stable ground (rocks are better than snow or mud).
Use a remote controller or self-timer when shooting from a tripod. Set IS (image stabilizer) to off on a stable tripod (but set it to on if you shoot handheld or on a flimsy tripod with strong wind).

7. ISO:

Use the base ISO (for example ISO 100 with the A7RII) whenever possible to reduce noise and increase the DR (dynamic range). Know when not to use base ISO (for example for handheld shots, nightscapes of stars, moving subjects, etc.).

8. Focus:

Always focus with LV at max magnification. Focus at the point where you get the best compromise between foreground sharpness and background sharpness. This depends a lot on the lens. For example, with the Zeiss ZF 15mm, you have to focus rather towards the background while with the Zeiss ZF 21mm it is often better to focus closer to the foreground. The reason for this is the strong field curvature (FC) of some lenses. It’s important to know the FC characteristic of your lenses and use it to your advantage. Sometimes it’s best to shoot the same image with different focus points and choose the best compromise afterward. Focus stacking can help in some cases (or the usage of a tilt-shift lens).

9. Shooting conditions:

Far away scenes/subjects can sometimes appear not sharp due to humidity or atmospheric moisture in the air or heat shimmer. Either get closer to the subject or wait for better conditions.

10. Postprocessing:

I only use Lightroom for PP. With other programs, you have other and sometimes more and better options for PP. With LR there are six really important sliders for the perceived sharpness of an image: Contrast, Clarity, Sharpening Amount, Sharpening Radius, Sharpening Detail, and Sharpening Masking. For details about these sliders, there are countless tutorials available on the web.
I often set the Contrast slider to quite high values (+30 .. +100) and use Clarity rather sparingly (0 .. +30). My default LR sharpening settings for A7RII files are 50/0.7/50/0 and for nearly noiseless images 50/0.7/100/0. It is important to adjust these settings to each individual image for the best-perceived sharpness, especially Clarity and Contrast. Regarding the sharpening sliders: I leave Amount and Radius for 99% of the images at 50 and 0.7 and adjust only Detail and Masking to each individual image depending on the subject and noise level.

11. Web images:

If you want to show your images on the internet you have to create images with a reduced size. I use the LR export function for this. Downsizing always leads to a softening of the images. Therefore you need some additional sharpening afterward. I use the LR Output Sharpening function for this step with the parameter set to either Standard or High. Often I export the image twice with both values and select afterward the image that looks better.
At this step, you could further improve the perceived sharpness of your web images by using complex Photoshop actions with downsizing and sharpening in several steps instead of the LR Output Sharpening function. Especially for small images, the perceived sharpness can be significantly improved with this method. Just google for step sharpening for more information about this concept. Since I don’t use Photoshop at the moment I rely solely on LR for my output sharpening.
Generally larger images with more pixel appear sharper than smaller images, especially if you use only the LR Output Sharpening. If possible I export my images with 1200 – 1600 pixels on the long side. But due to certain restrictions on many websites, this is often not possible.
If you use an image hosting service for the web presentation of your images upload the images in the same size you would like to present them and choose a provider which neither upsamples nor downsamples or otherwise changes your images. I use the pro service of Flickr which allows me to upload and present unchanged original images.

If you have any questions or further suggestions on how to improve the perceived image sharpness please use the comment field below this blog post.

4 thoughts

  1. An excellent summation of the critical variables, Boris. PP is important, as you note, but getting 1–9 right first is essential. Thanks for this.

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