| Aperture | ƒ/4 |
| Camera | Canon EOS 6D |
| Focal length | 17mm |
| ISO | 3200 |
| Shutter speed | 65s |
-
Mountains in diagonal

Aperture ƒ/8 Camera Canon EOS 6D Focal length 105mm ISO 100 Shutter speed 1/320s -
Spires of North Cork

Aperture ƒ/6.3 Camera Canon EOS 40D Focal length 72mm ISO 100 Shutter speed 1/80s -
Sunset at The Lough

Aperture ƒ/7.1 Camera Canon EOS 40D Focal length 10mm ISO 400 Shutter speed 1/250s -
Brandon Creek Road

Aperture ƒ/10 Camera Canon EOS 40D Focal length 10mm ISO 100 Shutter speed 1/200s -
The Limits of Lightroom’s Smart Previews

I just stretched the limits of Lightroom’s Smart Previews this morning.
After editing the following image I decided to see what it looked like as a smart preview. I pushed the image quite a bit, exposing the colour in the sky as the sun set behind me in Lanzarote a few days ago.
The original image is dull and lacks contrast but with a little work I was able to expose the lovely shades of magenta and orange present. Here’s what it looked like when Lightroom was editing a DNG file:

But when I removed the file and Lightroom had to use the smart preview this is what that lovely colour gradient looked like:

There’s visible compression artefacts visible that aren’t in the original and it looks more pronounced in Lightroom. I didn’t push the image too much, but these sort of artefacts can be seen in Jpeg images of smooth colour gradients like a blue sky has. They’re really visible if you push the contrast at all, or modify the colours in the gradient like I did with this image.
Smart previews create images that are 2500px wide or tall which is a good compromise between full size RAW and not being able to edit the image at all, but on a high resolution screen like a Macbook Retina screen you won’t be able to zoom much.
I will continue to use smart previews. My 1TB+ photo archive can be crunched down to less than 200GB which is within the reach of a laptop, and still leave free space. Once I plug my external drive back in and fire up Lightroom I can then export the images and be sure that the final image is what I want.
- Little Bunny (2006)
- Kilbrittain 6 miles (2007)
- The biggest drip in Cobh (2008)
- Flowers on North Mall (2009)
- Folsom Street Fair Four (2015)
- Dublin Street Photography (2016)
- Mahon Falls 2 (2017)
- Fly Away on a Rocket! (2018)
- Surfing at Stinson Beach (2021)
- The Colours of Autumn (2022)
- The Truman House (2023)
- Waiting in Colour (2025)























