While my Nikon D5100 camera only a 16MP sensor, the size of the images it produces can be quite large. While file size varies most files are between 3.5 MB to 5 MB. Uploading a full resolution image to my website would use considerable bandwidth and space on my server. Loading a full-size image also impact the performance of the website. Large images take a long time to load. This will be frustrating to my websites viewers. For this reason, I always downsize my images to between 960 pixels to 1024 pixels on the long side. While this reduces the file size considerably, it may not be enough. I could reduce the file size further by uploading smaller images -- e.g. 640 pixels on the long side. However, I feel that small images sizes just don't work well for many of my images. I think it's hard to see detail when the images are too small. Ideally, I would be able to display my images at a decent size while also reduce the size of the images. That's where image compression comes in.

JPEGmini is a photo optimization technology that reduces the file size of JPEG photos while preserving the resolution and quality of the original photos. The software is available in two consumer versions, JPEGmini ($20) and JPEGmini Pro ($99). Both are available as Trial downloads. JPEGmini is available for Windows and macOS with support for Adobe Lightroom 5 and later Photoshop: CC 2015.1 and later.

I have used JPEGmini Pro for a few years as part of my workflow for posting images to my WordPress website. The software reduces the file size of my photos significantly, saving me space on a server and speeding up my website. JPEGmini Pro includes a plug-in for Adobe® Lightroom® and a Photoshop® extension! I have used it successfully with the Creative Cloud version of Lightroom and Photoshop. When I export my photos directly from Lightroom or Photoshop, they are automatically optimized by JPEGmini to the lowest file size possible without ever sacrificing quality. The plug-in can be integrated with any of Adobe® Lightroom’s export presets.

While JPEGmini Pro has worked well for me I have never done a comparison test with other software. A recently article in MacWorld promote me to take a look at alternatives. The article was a cursory review and comparison of Realmac’s Squash ($20) to JPEGmini Pro. I am not sure why the author chose to compare Squash to the JPEGmini Pro when JPEGmini is available for $20. To me the comparison was unfair and I took issue with this on MacWorld’s Facebook page. One other person agreed with me and indicated that he got good results with the FREE ImageOptim app for macOS. Other commenters suggest that using the image quality slider in Adobe Lightroom would be just as effective. I wanted to do my own test.

For this test, I compressed images with each of the following: JPEGmini, Squash, and ImageOptim. I will compare each software with JPEG quality set to 100% and then 70%.

I used two images. The first image was my bird landing photo from a few weeks ago. From Lightroom I exported a full resolution 3692px x 3264px JPEG at 100% quality. I then compressed copies of that image with Squash, JPEGmini, and ImageOptim with the quality sliders set at 100%.

The second test image is one I captured last month at the Twin Lights Lighthouse in the Highlands, New Jersey. I exported that image from Lightroom as a 960px x 636px JPEG image at 100% and 70%. I compressed the 100% version with Squash, JPEGmini, and ImageOptim with the quality sliders set at 70%.

I also exported all 180 of my January 2017 images from Lightroom to a folder. That took a VERY long time. I then exported the same set of images from Lightroom as 960px x 636px JPEG images with the quality slider set to 70%. The 100% JPEG export folder was compressed with Squash, JPEGmini, and ImageOptim with the slider set to 70%.

Here are the results.

Table 1 JPEG Compression App Test

File size and percentage reductions of a single 3692 x 3264 pixel JPEG exported at 100% quality.
Original JPEGJPEGminiSquashImageOptim
4 MB839 KB5.5 MB3.8 MB
NA~79.5%~27.2% increase5%

JPEGmini is the clear winner here. ImageOptim minimally reduced the file size. Squash made the image file larger.

Now for the folder containing the 180 JPEG images exported at 100% quality.

Table 2 JPEG Compression App Test

Folder size and percentage reductions of 180 full resolution JPEG images exported at 100% quality.
Original FolderJPEGminiSquashImageOptim
1.82 GB752.9 MB2.66 GB1.73 GB
NA~59.6%31.6% increase~2.7%

The results are similar to above. Truthfully, the test above is not fair. While all the other software has a quality slider which I set to 100%, JPEGmini does not. I suspect that JPEGmini has a quality algorithm that is always on. I don’t know what that value is. It could be anywhere from 70-90%. It could be less. It could be dynamically adjusted based on data gathered by the app from the image file. In any case, I needed a test that is fairer to the other apps.

The second test image is one I captured last month at the Twin Lights Lighthouse in the Highlands, New Jersey. I exported that image from Lightroom as a 960px x 636px JPEG image at 100% and 70%. I compressed the 100% version with Squash, JPEGmini, and ImageOptim with the quality sliders set at 70%.

Table 3 JPEG Compression App Test

File size and percentage reductions of a single JPEG exported at 100% quality and resized to 960 x 636 pixels then compressed with the quality slider at 70% and 80%. The original file size is 639 KB.
Quality SliderJPEGminiSquashImageOptimAdobe Lightroom
100%229 KB844 KB606 KB639 KB
90%229 KB270 KB197 KB459 KB
80%229 KB213 KB147 KB328 KB
70%229 KB188 KB123 KB254 KB

When the quality slide is set to 70%, the image file size is reduced considerably. Squash and ImageOptim performed best with ImageOptim reducing the image by about 80%. JPEGmini did not fare much better than just setting the image slider in Adobe Lightroom to 70% at export.

Now for the folder containing the 180 JPEG images exported from Adobe Lightroom at 100% quality and compressed by Squash and ImageOptim with the slider set at 70%. For comparison, I also exported the same images from Lightroom with the quality slider set to 70%.

Table 4 JPEG Compression App Test

Folder size and percentage reductions of 17 full resolution JPEG images exported at 100% quality and then compressed with quality sliders at 70%, 80%, and 90%. Also included is the Lightroom images exported at 70%, 80%, and 90%. Original folder size is 9.2 MB
Quality SliderJPEGminiSquashImageOptimAdobe Lightroom
100%3.4 MB11.9 MB8.7 MB9.2 MB
90%3.4 MB4.1 MB2.9 MB6.6 MB
80%3.4 MB3.3 MB2.2 MB4.8 MB
70%3.4 MB2.8 MB1.8 MB3.7 MB

When the quality slide is set to 70%, the entire folder of images is reduced in size considerably. ImageOptim performed best, reducing the image by about 88%. JPEGmini and Squash did worse than just setting the image slider in Adobe Lightroom to 70% at export.

In my test, ImageOptim performs best at reducing the file size of JPEG images with the quality slider set to 70%. When the quality slider is set to 100% Squash increases the size of the image file. That's exactly the opposite of what I want to accomplish. ImageOptim performs only slightly better when the slider is at 100% quality.

From my perspective, there is no clear winner here. Squish, with the slider set to 70%, does a slightly better job than JPEGMini. However, ImageOptim beats both of those by a significant margin. Given that ImageOptim is free, I think that would be the best option if you don't need integration with Lightroom.

If you need to export and compress directly from Lightroom to a folder or, in my case, a WordPress website, then JPEGmini Pro will offer convenience. I use the plug-in with all my blogs posts. I think it is more efficient to export from Lightroom directly to the WordPress media library, than to export to a folder, compress the contents with an image optimization tool, then open a browser, log-in to the website, then upload to the media library.

I didn't test for the quality of the images. I think that is subjective and could vary with each image. You can judge for yourself from the images below. It seems to me that ImageOptim achieved a small image file size by compromising quality. The image has a lot of compression artefacts. I could not visually discern a difference between the images compressed by Squash, JPEGmini, and Adobe Lightroom’s 70% slider.

Lightroom
Original image exported to 960 × 636 pixel JPEG at 100% quality
  • Aperture—ƒ/8
  • Camera—NIKON D5100
  • Taken—29 January, 2017
  • Focal length—16mm
  • ISO—100
  • Shutter speed—1/1250s

Lightroom
Original image exported to 960 × 636 JPEG image at 70% quality
  • Aperture—ƒ/8
  • Camera—NIKON D5100
  • Taken—29 January, 2017
  • Focal length—16mm
  • ISO—100
  • Shutter speed—1/1250s

Squash
Original image exported to 960 × 636 JPEG image at 100% quality and then compressed with Squash at 70% quality
  • Aperture—ƒ/8
  • Taken—29 January, 2017
  • Focal length—16mm
  • ISO—100
  • Shutter speed—1/1250s

JPEGmini
Original image exported to 960 × 636 JPEG image at 100% quality and then compressed with JPEGmini.
  • Aperture—ƒ/8
  • Camera—NIKON D5100
  • Taken—29 January, 2017
  • Focal length—16mm
  • ISO—100
  • Shutter speed—1/1250s

ImageOptim
Original image exported to 960 × 636 JPEG image at 100% quality and then compressed with ImageOptim at 70% quality
  • Aperture—ƒ/8
  • Camera—NIKON D5100
  • Taken—29 January, 2017
  • Focal length—16mm
  • ISO—100
  • Shutter speed—1/1250s

Automattic recently released a plugin for Adobe Lightroom that instantly simplified my photography publishing workflow. The plugin allows the user to export images direct from Lightroom to WordPress.com or a self-hosted WordPress website.

Installing, configuring and using the plugin was straightforward and easy. I’ll explain how it’s done.

Installation

Download the plug from WordPress.com and unzip the plugin file. The plugin has the following file name: wordpress.com.lrplugin. Launch Adobe Lightroom and navigate to the Plug-in Manager. On the Mac, you can find the entry under the File menu. Alternatively, use a Mac keyboard shortcut ...

lightroom

From the Plug-in Manager winder click add in the bottom left corner of the plugin manager, navigate to the location of the wordpress.com.lrplugin file and select the plugin.

I suggest copying the wordpress.com.lrplugin file to the folder where Lightroom keeps the rest of its plugins. You can find this easily.

lightroom

Select one of the pre-installed plug-ins in the left pane of the Plug-in Manager. Then click the Show in Finder button in the Status section. On MacOS, this will open a Finder window to this location.

Copy — drag, and drop — the wordpress.com.lrplugin to the Adobe Lightroom plugin folder, then restart Adobe Lightroom. The plug-in is now installed.

Setup

Setup for a WordPress.com or self-hosted WordPress.org website is done the same way. However, to upload to your self-hosted WordPress (.org) website, you need to install the Jetpack plugin, which you can do by following the instructions on WordPress.com.

lightroom

Click the Log In button. This will launch your browser. You will have to log in and authorized the plugin to use your WordPress.com. You will be taken back to Adobe Lightroom once the connection is approved. Once that is done, make sure your site is selected from the drop-down list.

lightroom

That’s it. In the past, I had used another plugin called Photo Upload to export from Lightroom to WordPress. However, that plugin was more challenging to set up and use and is not free. The free WordPress plugin is as easy as to use as selecting one or more images in Lightroom, clicking the Lightroom export button and picking my blog.