Luminar 4 Sky Replacement Tutorial and Review
What Is A Sky Replacement?
You’ve come here to find out about sky replacements in Luminar 4 so chances are you already know what a sky replacement is. If you don’t know then put simply, a sky replacement is where you replace the sky part of an image with the sky from another image. It’s really as simple as that.
Why Would You Want To Replace the Sky In Your Photograph?
I think we can all relate to those times when you have meticulously planned a photography trip, only to have the weather let you down. I can recall dozens of journeys to some wonderful locations only to be met with clear blue skies or a dull grey blanket of cloud as far as the eye can see. I always set up my camera and make the most of the conditions - if only to test the ‘you never know what will happen’ theory… The problem is that nine times out of ten, those dull skies will mean those images will either be deleted once they make it into Lightroom or they’ll be added to a catalog and forgotten about.
Being able to replace the sky in those ‘wasted’ images will mean you can hopefully rescue the image and ‘drop in’ a sky more suited to the photograph you envisaged when planning the shot. Imagine being able to replace a blue-bird disaster with the most glorious array of pink and red tinged clouds ever to be seen in the sky - pretty good, right?
Sky Replacements Using Photoshop
Luminar didn’t invent the concept of replacing the sky in an image. Photoshop (and similar software packages) has been used for years to blend the sky from one image into an other. There are tutorials all over the internet that guide you step by step on how to change the sky in your image using layers, blend-if, masks and a whole host of other Photoshop components. If you already have Photoshop then you do not need to purchase Luminar 4 to be able to replace the sky in an image. So why would you want to?
Tutorial - Luminar 4 Sky Replacement Tool Explained in Three Easy Steps
It’s quick, it’s simple and - spoiler alert - it does an amazing job. Luminar uses machine learning algorithms (AI) to help understand your image and makes automatic adjustments based on the replacement sky that you select i.e. if you select a fiery sunset sky, the AI will pick up on this and ensure that your overall image tone is suitable warmed up to cater for the new sky. Luminar’s AI will also identify non-sky objects in the image to ensure a smooth transition from the sky to the rest of the image. No need for complex masking or blending here - although as I explain in the tutorial and examples below, you can make fine adjustments to tone, orientation and blending if you’re not 100% happy with the job the AI did.
Let’s take a step-by-step look at a real example of where I replaced the sky in an image.
Step One: Import Your Image Into Luminar 4
There are a few ways to Import your image into Luminar 4. I personally do this from Lightroom or Photoshop but you can also process RAW files directly in Luminar 4 without the need to go through the Adobe suite first.
In Lightroom, after selecting the image that needs a sky replacement, all you need to do is: right-click, select ‘Edit In’ then choose Luminar 4. This will open up Luminar 4 and bring the image in as a TIFF file.
Step Two: Select Your Image’s New Sky Using the Sky Replacement Tool
Once your image is in Luminar 4 you need to select the Creative workspace on the right then the AI Sky Replacement tool.
Luminar 4 comes with a selection of ‘built in’ skies to choose from including a selection of sunsets, starry and cloudy blue skies. In total there are 29 skies to choose from, however, you can buy more from the Luminar Marketplace or even select your own skies if you have some fantastic skies to re-use already.
In the St Pauls Cathedral example I’ve opted for ‘Sunset 1’ just to give the small patch of visible sky a touch of colour and wispy cloud that was missing from the original.
Already the image looks much better and a lot more dramatic than the original.
Step Three: Make Fine Adjustments To Your Sky Using The Sky Replacement Options In Luminar 4
There are several options available within the Luminar 4 Sky Replacement Tool. Luckily, the default settings have not needed much tweaking in my experience to date but let me explain a few key options to keep an eye on after selecting your new sky:
Horizon Blending - Move this to the right to add a more gradual gradient between the sky and the rest of the image.
Horizon Position - Did the Luminar AI put the horizon line too high/low by a few pixels? Move your horizon up or down using this slider.
Relight Scene - This is really important as it adjusts the tone and warmth of the image to give a more balanced and natural blend between your original image and the new sky.
Sky Global and Sky Local - Two sliders that have not needed much adjusting. The global slider was useful on one image where some of the new sky came through into the foreground. A quick tweak to this slider removed the sky artefact from the non-sky portion of the image.
Close Gaps - I’ve kept this below 15 on all my images so far. It is useful when there are objects intruding into the sky which the AI may by default have difficulty identifying. Overall it makes the sky blend in more naturally to the rest of the image.
Sky Defocus - Not needed to use this so far but it does indeed make the sky look out of focus.
Flip Sky - An obvious option where the sky is flipped on its vertical axis. This is really useful if you know that in your composition, the sun would look more natural setting on the right or left of the frame.
Sky Temperature and Exposure - Similar to relight scene, this will allow you to fine tune the tone of your new sky.
St Pauls Cathedral Sky Replacement Complete!
After fine tuning the sky and completing the image edit in Luminar 4 we now have a photograph I’m happy with. The sky replacement has turned an image that was lurking in the 3 star bucket in Lightroom into something that could make it into a portfolio. It really was a simple process, the sky replacement task took much less time than the rest of the edit and in total I spent about ten minutes on this image. Something to take notice of here is how good a job Luminar did of detecting non-sky objects in the image such as the Cathedral’s dome. I was fairly certain that the intricate stonework of the Cathedral’s spire would confuse the AI but as you can see, it’s perfectly replaced the sky without leaking pixels onto any of the buildings in the image. That is really impressive and means this tool isn’t just for landscape photography but can be applied to portrait and architectural work too.
More Luminar 4 Sky Replacement Examples
The sky in the St Paul’s Cathedral photograph was quite a small area in comparison to the rest of the image so I wanted to show you a couple of my landscape images where the sky forms a larger part of the overall photograph.
Budapest Skyline BEFORE Luminar 4 Sky Replacement
Budapest Skyline AFTER Luminar 4 Sky Replacement
Pultney Bridge BEFORE Luminar 4 Sky Replacement
Pultney Bridge AFTER Luminar 4 Sky Replacement
In both of the examples above I’ve taken cityscape photographs that I was very happy with - except for the sky. These sat in my Lightroom catalog gathering digital dust until I received my early copy of Luminar 4. Having replaced the skies I’m now genuinely pleased with the end result and very impressed at how effective the sky replacement tool is.
Are Sky Replacements Cheating?
This is one of those questions that really comes down to personal preference. Whether you are dropping in a new sky or making significant changes to colour hue and saturation, what you are doing is artistically editing the image to have a desired effect on the viewer. Some audiences will look at an image that has been artistically edited and immediately dislike it or condemn the unrealistic editing whilst others will accept the photographers end product for what it is - art.
So is it cheating? For me the answer is no but personally I would still prefer to capture the scene - including the sky - myself. If a client specifically asks for an image to be true-to-life and not significantly edited then you should respect that request and leave the sky and other significant alterations alone. Other than that, if you have an image that would benefit from a sky replacement either artistically or to tell a story then go ahead! It’s your work!
Outside of this tutorial I won’t be replacing the skies in my images that I share or sell as prints, however, I will definitely use the tool to check how a composition might look with a different sky or a change in lighting. I could then use that info to revisit the location at a later date and capture the shot in my own way.
Luminar 4 Sky Replacements - Final Verdict
Having now used both Luminar 4 and 3, I can safely say that this software will remain a key part of my workflow alongside Lightroom and Photoshop. Putting Sky Replacements aside for a moment, there are many other great tools that I make use of in Luminar; Orton Effect, Details Enhancer and Vignette to name just a few that I used regularly. Just like Luminar 3, this new version allows me to make my initial adjustments in Lightroom or Photoshop, then complete the edit in Luminar.
The AI Sky Replacement tool is definitely an interesting addition. It is very simple to use and from my experience to date, does a great job with just a few adjustments of the associated sliders.
Skylum, the developers of Luminar, have produced a fantastic overall package that is intuitive and lets you get creative with your photography without needing to know lots of Photoshop tricks. The Sky Replacement tool will inevitably divide opinion but what can’t be argued is how effective it is.
Download Luminar 4 And Start Creating Amazing Images Of Your Own
Hopefully you’ve found this tutorial and review useful and are now ready to take a look at Luminar 4? If you want to grab a copy, you can save yourself $10 by clicking the link below and use the discount code LUMINAR-FRIEND at the checkout.
This is an affiliate link which will help me a little and will cost you nothing extra. I hope you enjoy using the software as much as I have - let me know.
Luminar 4 AI Augmented Sky Update (2020)
Keeping up with their pattern of cutting edge AI innovations, in 2020 an update to Luminar 4 saw the introduction of an even more advanced sky adjustment tool called ‘AI Augmented Sky’. This uses similar algorithms to detect the sky in your image but instead of a full sky replacement it will seamlessly embed objects into the sky. This can be used to achieve some very interesting results ranging from the subtle addition of clouds to the crazier introduction of a rocket launch! This is not to everyones tastes and further adds to the art vs photography debate but there is no doubt that the creators of Luminar 4 are committed to delivering fantastic updates to their software. I’m looking forward to what they think of next.
