Are you ever disappointed with your photos? Do you get frustrated when you’re editing because you’ve been told to move certain sliders, but never been told WHY? Do you wish you could transform your photos without having to spend hours in front of the computer?
In my new book, Adobe Lightroom - Edit Like a Pro, you’ll learn:
how to to analyze a photo like a pro, saving you hours of frustration.
WHY you might want to move specific sliders, instead of just following recipes.
what the sliders are doing behind the scenes.
how to use sliders together, instead of in isolation, so you can get the optimal result
The book is based on the cloud-native Lightroom desktop and mobile apps, but the principles also apply to Lightroom 6 and Lightroom Classic. The sliders are arranged into slightly different panels, but there's an included PDF that shows you where to find them in Lightroom Classic/6.
To change the background, no. You need a layers editor to do that (such as Photoshop or Affinity Photo).
To blur the background. Not something I would attempt in LR, others might chip in with how they would go about it. Again, a layers editor job, if you want to do it well.
To darken the background, possibly. LR has a develop module tool that will darken (or lighten) an oval shape. Go to Develop>Effects>Post-Crop vignetting. Move the 'amount' slider up and down. The other controls vary how 'round' the shape is, how quickly the effect is transitioned in (feather) and a few others, try them to see what they do.
BTW, I use 6.14, so far as I am aware the latest versions of LR have not changed this capability significantly.
While LR can make local adjustments, it isn't really much good at it, especially for large and complex shapes. Layers editors work in a very different way. I prefer to think of LR as a raw editor, making changes to the whole image. Yes, I'll occasionally fix a dust bunny or other local adjustment, but it quickly becomes painful (horribly slow) in my experience. Layers editors are much, much better at such changes. Use LR to get the whole image as close to right as possible and then work in a layers editor. I might add that I rarely use a layers editor, I find the processing commands in LR are entirely adequate to convert raw data into a publishable final image, but then, I'm not blurring out the background etc, I aim to do that in camera.
Thank you. I tend to try and get it in camera too, however I have an image that I like but I'm not happy with the background. I have photoshop as part of the cloud deal but currently I want to become more proficient in camera and with Lightroom. I'll have a go with your tips on darkening the background.
And what about the Range Mask of the Graduated Filter, the Radiated Filter resp. The Adjustment Brush? The range Masks help in a lot of cases, so you don't have to go to Photoshop. May be, that there was no range mask in Version 6.
It really depends on how "separated" your subject is from its background, and how complex your subject is. First thing to try is to use the Adjustment Brush to paint over the background (and use "Auto Mask" if possible to paint closely to your subject), then to blur the background you can decrease the clarity, or sharpness, or texture, or some combination thereof. To darken, decrease exposure or any of the other "brightness" controls.
Alternatively, as hanoman has suggested, you can use the range mask with any of the local adjustment tools (graduated filter, radial filter, adjustment brush) to mask your changes to a specific colour or luminosity range.
How well this works will depend on the specifics of your image, but it's always worth a try before going to Photoshop or some other editor. You can't really "change" the background though, if you are thinking along the lines of sky replacement or some such thing.