Adobe Lightroom techniques

optimising your export for Facebook

FB will create multiple versions of your image, each with a different size
width should be a multiple of 480 pixels (eg. 960 for a portrait or perhaps 1920 pixels for a landscape image) to allow FB to resize to 480 pixels with better image quality and minimise banding (if you still get banding, consider adding a small amount of noise)
FB's algorithms tend to lose your high frequency data - that is the fine detail, so if you don't want your image looking too blurry, ensure you middle frequency data is optimised - that is - the image details you can see without pixel peeping
if using layers in PS then duplicate your image then flatten the layers before resizing
currently there does not appear to be any advantage of PNG over JPG as FB will convert to JPG if your PNG is larger than 1Mb

Youtube tutorial cloudy day waterfall in Iceland by Attilio Ruffo
avoid edge halos by using dual gradient filters with luminosity masks rather than by just reducing highlights and increasing shadows which will cause edge halos - see https://fstoppers.com/education/dont-ever-do-editing-mistake-282438

just select the images you wish to use then right click and select Panorama
then you get a preview and can choose which option - spherical, cylindrical or perspective

over-expose skin in camera without getting blown highlights - then reduce exposure in Lightroom to suit - this gives more tonality and smoother skin with less noise
ensure white balance is accurate
apply lens profile correction if available for that lens
straighten and crop image
set overall sharpness level to exclude skin:
- masking = 90-94 or so

using the HSL method:
- zoom in on the subject's face
- go to HSL section, click on HSL
- for each of hue, saturation and luminance, sequentially adjust each by dragging the marker onto the skin and adjusting up or down as needed
using the RGB curve method ¹⁾:
- go to the Tone Curve and click on the small curve icon and this will allow you then to select channel
- select channel red
- drag the marker to subject's skin and read off the value eg 74%
- repeat using the same bit of skin for each channel
- calculate an adjustment value = (red - blue)/2
- set the red channel on that skin to equal the green value + the adjustment value by holding down the shift key as you change it
- set the blue channel on that skin to equal the green value - the adjustment value by holding down the shift key as you change it
- fine tune green channel to taste

A great tutorial for Lightroom 5 users:

Fixing skin tones in Lightroom using only 3 clicks:

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