A Guide to Colourising Photographs Using Adobe's New Colorize Neural Filter in Adobe Photoshop CC
In the recent versions of Adobe Photoshop CC, Adobe has introduced several new neural engines for restoring and colorising old black and white photographs. So as an avid photo-restorer and image editor I recently decided to put Adobe’s Colorize Neural Filter — which boldly claims to be able to colour old black and white photographs — through its paces to see what it can achieve and understand any implications for my own image editing workflow.
The results of my first experimentations I covered in a previous blog post, and in this follow-on post I want to dive a little deeper into the process of colourising old black and white photographs using Adobe Photoshop’s Colorize neural engine and guide you through the process of colouring old photographs in general.
A photograph of Cap Aokas taken by my late grandfather in 1942. I recently restored and colourised this photograph in Adobe Photoshop using the Colorize Neural Filter and additional colouring techniques.
How To Capture Your Images For Colourisation
Before we get started with the process of colourising an image, we need to discuss how to best capture the image because the quality of the digital copy, e.g. scan or photographic copy, has a large bearing on the overall quality of the Colorize neural engine’s results. Lower quality images will aversely effect the results which the neural engine is able to produce. Basically the more information you are able to capture in your image, and the higher the quality of that information, the better the results produced when processed with the Colorize Neural Filter.
How you capture your image for restoration and colourisation really depends on the equipment and resources you have available. In the best case scenario, you have got the original photographic negative and a dedicated negative scanner. These machines are able to scan negatives at very high resolutions. Some flatbed scanners have a basic negative scanning facility built into their lid; these are almost as good as a dedicated negative scanner, but do have some limitations because they are a compromised solution. When scanning negatives using a dedicated negative scanner, and with the correct settings, the only real limitation is those of the original photograph and the condition of the negative, which might have become scratched and/or dusty over the intervening years.
Of course, using a dedicated negative scanner is not always possible, especially if you do not have the photograph’s negative. In this case you might find yourself photographing or scanning a print. Prints are best scanned using a high quality flatbed scanner.
When putting your photograph in the scanner, it is important you get the photograph as flat as possible. Now this might seem a little obvious, but old photographs — like some of those which I have been dealing with recently — often bend and warp over time, depending on the condition in which they have been stored. If you find yourself in this situation, you can try gently resting several heavy books on top of the print when it’s in the scanner. When using a flatbed scanner, if the surface of the print is not in contact with the scanner glass, then that area of the print may scan out of focus or softly.
If you do not have a dedicated negative scanner or flat bed scanner, do not fret, because there are several other methods you can use to capture your photographic print or negative. Simply photographing your print is perhaps the easiest. You can do this by tacking it to the wall and photographing it using your phone or camera, in as neutral light as possible. Unless you have got proper lighting equipment, e.g. a flash head or studio lighting kit, avoid photographing the print with the camera or phone’s flash, because these tend to produced rather blitzed results! Also watch out for any strong light sources, e.g. lamps in the background or daylight coming in through a nearby window, reflecting off the surface of the print. Neutral light means diffused and indirect.
Nowadays however scanning your negatives or photographing them off the wall are not your only options. There is now several apps which utilise your mobile phone’s camera to capture negatives and prints. For example FilmBox is an app which you can use to scan your negatives for free using their basic account, and with an extra subscription you can have access to more advanced neural tools.
All of this said, no matter what method you use to capture your negatives or prints, scanning or photographing them in the highest possible resolution is paramount. And this is where dedicated negative scanners usually have an advantage, because they are specially designed to scan a small area, but in an extremely high resolution. For example my Plustek OpticFilm 8100 negative scanner can scan at 7200 dpi and in 24-bit colour, which is far higher than my flatbed scanner! If you are photographing a print tacked to the wall, you’ll need to get as close as the focus on your camera allows, and then maybe crop the image afterwards in Adobe Photoshop or equivalent image editing software. Of course, when using a camera, how close you can focus depends on the focal length of the lens and the camera’s image sensor size. Mobile phones, with their tiny sensors, which are typically of inferior quality, actually have an advantage here because they can focus closer.
But to summarise, scanning or capturing your images in the highest possible resolution and quality will make both the processes of colourisation and image restoration easier and enable you to produce better results. Basically do it right first to succeed. A poor quality image will always be harder to colourise and restore.
Opening Your Image In Adobe Photoshop CC & Initial Steps
With your scanned negative or photographed print ready, the first thing to do is open it in Adobe Photoshop by going to the File menu and selecting Open… or by using the shortcut (Command + O on Mac or Ctrl + O in Windows). This will open up your image in Adobe Photoshop and you can then prepare your image for colourisation.
It is entirely possible that your image, before colourisation, might also need some restoration to remove any dust and scratches. These processes I will not be covering here, but have another blog post where I run through the basic tools required and also teach a class on the subject which is available both on Skillshare and Teachable. I recommend that you thoroughly restore your photograph before embarking on the colourisation process. This is because when restoring the photograph you might be dealing with several layers and adjustment layers, and it is easier to get this part of the process out of the way and finished first.
Before we get started with the colourisation process, there are a couple of things to check. Firstly we need to ensure the image is in the RGB colour mode, otherwise Adobe’s colourisation neural engine will not work! To check your image’s colour mode go to the Image menu and Mode to see what colour mode is selected. If you image is set to Greyscale (or anything other than RGB), select RGB from the menu. This action will not convert your black and white image into a colour image, but will allow Adobe Photoshop to use colours when colourising your image. If your image file has any layers and/or Adjustments applied, then you might get a message asking you if you want to flatten the image when converting it to the RGB colour mode, however this is not necessary, and you do not need to to flatten your image.
Le Pardon statue by Ernst Dubois in Skikda, late-1942. My grandfather was in the Royal Signal Corps and served in North Africa, Italy and the far-East during the Second World War. During his travels, which involved much down-time working behind the lines, he was able to take many photographs of the sights and places he visited.
Besides setting up the colour mode correctly, you might also want to resize, crop or straighten your image, although this is arguably part of any image restoration process. It is best to get this part of the process done before colourising your image because removing areas of the image, e.g. damaged margins from where your print might have become folded or creased, will make the overall process easier and faster. To crop the image use the Crop tool from the Tool panel. Resize your image using the Image Size tool located in the Image menu and straighten / rotate your image using the Free Transform tool, which is accessible through the Edit menu or by hitting Command + T on mac or Ctrl + T in Windows.
Getting Started With Adobe’s Colorize Neural Filter
So you’ve opened your image in Adobe Photoshop and are now ready to start colourising it using Adobe’s Colorize neural engine.
Select the layer with your photograph in the Layers panel, or if you have multiple layers in your document (for example retouching layers and adjustment layers), select all of the image layers you might have, and convert them into a Smart Object. This will help you avoid running into any issues with the neural filter and allow to have a full-proof non-destructive workflow, and you can always release your Smart Object (right-click and select Convert to Layers) later on if required. If you have any adjustment layers, keep them outside and above your new Smart Object.
With your image selected, go to the Filter menu and select Neural Filters…. This will open Adobe Photoshop’s Neural Filter Gallery where you can select and apply the various different filters to your image. To colourise your image, download and turn on the ‘Colorize’ option which is about halfway down the list of filters. When you do this your computer might take a moment to process things whilst it colours your image. In the panel on the righthand side of your workspace the settings for the Colorize neural filter will open; these you can use to control the filter and what you choose to output.
Adobe Photoshop's Colorize filter's basic workspace. This is what you should see once you have opened your black and white image in the Colorize Neural Filter and it has processed the image. No additional changes, settings and corrections have been made at this point.
Filter Profiles & Profile Strength Setting
Once your computer has finished processing the Colorize filter’s initial output, you can customise the filter and further fine-tune its settings to better suit your image. Firstly in the Adjustments section you have a range of profiles which can be used to quickly change the filter’s parameters. Options include Retro High Contrast, Retro Blue Brown, Retro Light Yellow, Retro Purple Yellow, Retro Bright, Retro Red, Retro Green, Retro Faded, Retro Denim, Retro Dark and Retro Brown. There are no hard rules to follow here, it really depends on your image and how you want your image to look. So if this is your first time experimenting with Adobe’s neural engines, then work through all the filters profiles and find one which works for you. These filters are specially designed to work with and mimic old prints, so you’re bound to find something which will work with and enhance your image.
Having selected a filter profile or having decided to keep the Colorize filter’s default colour settings, next you can control the strength of the filter (if you have selected a filter profile) using the Profile strength slider located under the filter profiles. The slider’s default setting is in the middle, or 50%. And moving it to the right will increase the strength of the filter profile, whilst moving the slider to the left will decrease its strength. Again, play around with this slider and get your image and the strength of the filter looking just right for your image.
The Colorize filter Adjustments panel with the ‘Retro Denim’ Profile selected. The Profile Strength slider underneath can be used to control the strength of the Profile.
Saturation & Colour Balance Controls
Underneath the Profiles and Profile Strength control is a Saturation slider and several colour balance controls. The Saturation can be useful because old photographs, when colourised, often have overly saturated colours, or can be desaturated and need their colour saturation boosted.
And likewise sometimes the colour balance can be a little off, even when you’ve carefully selected a profile. Or perhaps you deliberately want to push the colour balance of your photo in a particular direction, for example giving your image a faded reddish look as if the acid in the photographic paper has reacted with its environment — these sliders will allow you to take some control of the image colourisation process.
Color Artefact Reduction & Noise Reduction
After you have finished setting up your Colorize neural filter, there are several additions controls to explore for fine-tuning your look, these are Color Artefact Reduction and Noise Reduction.
The Color Artefact Reduction control, allows you to adjust the colouring in your image by smoothing some areas and sharpening other. When set to maximum, or high values, it also affects the general colouring, as it tends to somewhat blend the hues together. But with lowers values, nine times out of ten you will not notice much difference, if any, to your image.
On the other hand, the Noise Reduction control can appear to have an unwanted effect on the overall image quality, texture and tone, especially when you crank it up to its maximum value. But don’t be discouraged by what you see, as there is a way of making it work to your advantage.
In order to do so, you need to make sure that you don’t bake this effect into the actual image layer. This you can do when outputting the filter’s results later on by checking ‘Output as new color layer’ tickbox. When you check this box, you’ll see the colours used to colourise your photograph, but not the details of the actual photograph, and when you start changing the Noise Reduction value, you’ll notice that it creates smoother colouring and blends the colours together when you increase its value, so there is less or no colour noise. It does not affect the colouring as such as the Colour Artefact Reduction slider does, but just makes all of the transitions smoother.
As you cannot easily preview the effect at this stage without applying the filter, you can save making the Noise Reduction changes until just before outputting the results. And if you want to work on the filter’s settings more, simply turn it back down to zero and uncheck ‘Output as new color layer’ tickbox to see the colourised preview yet again.
Even when you use Color Artefact Reduction and Noise Reduction controls to compensate for blotchy colouring, they won’t go far if you have got areas with uneven colouring, where AI got it wrong — those you will need to address separately and manually adjust the colours in the problematic areas.
Output Options
All of that said, we have now reached the important end part of the process — the output options. Adobe’s neural engines, partly by design, but also limited by their current state of development and power, are meant to compliment any traditional colourisation process. So when it comes to outputting the final results from the neural filter, it is best to export it as a new colour layer, meaning you’ll be able to edit and replace the colours afterwards at ease. To do this, select the ‘Output as new color layer’ tickbox. As mentioned earlier, when this box is checked, the image displayed will change and you will see the colours Adobe Photoshop has painted over your image. Once you select ‘Okay’ and return to Adobe Photoshop’s standard workspace, these colours will be displayed as a new layer with the Color blending mode selected, creating the colouring effect over the layers below.
Working this way will mean that you can easily change the colours afterwards because all of the colouring is contained on a separate layer, and therefore this is my way preferred way of working. You do however have several other output options in a menu at the bottom of the Colorize Neural Filter panel (available when the ‘Output as new color layer’ tickbox is not checked). These are as follows:
Current layer, which will output your colourised image onto the current image layer (so it is a destructive option);
New layer, which will output the colorised image as a new layer (above the original image layer in the Layers panel);
New layer masked (the same as previous, but setup as a mask to you can remove parts);
Smart filter;
and New document.
Layer Preview & Show Original
Besides all of the settings Adobe’s neural colorisation filter has for controlling the filter effect, there are a couple of useful tools tucked away at the bottom of the Colorize panel. These are the Layer Preview control and the Show Original option. Show Original does exactly what its name suggest, and when you click on this option it will show you how the image originally looked.
The Layer Preview can be used to jump between displaying all layers with the filter’s effect, or the individual layer you had selected when you opened the neural filters, which should be your image layer. This can be useful if you are working with a file which has some adjustment layers above your image layer, and want to preview either the final overall result with all additional adjustments in the document or just the colourisation effect on the image without additional adjustments.
Are You Satisfied With The Results?
Obviously Adobe has not quite finished developing the Colorize neural filter, because under all of the controls and options is a feedback question asking if you are satisfied with the results. Obviously complete this as you will, but consider the following point, bearing in mind what I will be talking about next… Adobe’s Colorize filter is really designed as a starting point. When colorising an old black and white image it will get you perhaps 80% of the way there. But however it is not perfect, and will frequently make mistakes with particular colours. I have noticed through using the filter that greens and blues appear to be particularly vulnerable to being mistaken by the neural engine. That said however, there are areas in which the neural engine seems to excel, like dealing with faces and skin tones, which are arguably very complex and perhaps the hardest thing to get right! Most of my post-neural filter work on colorised images is to fix erroneous greens and blues. I have had to do relatively little work, thank goodness, on skin tones!
So to finish off, lets have a brief look at working with colorised images post-application of the Colorize filter.
A portrait of my grand father Pete taken by Wykeham Studios (London) in the mid-1930s. Adobe Photoshop’s Colorize neural engine has done a good job with his skin tones and hair colour, which having cross-referenced with other colour photographs, are correct.
Working With Your Newly Colorised Image in Adobe Photoshop
When you are happy with the results of the filter, click on the Okay button to apply the colorisation process and exit the neural filters. As mentioned previously I have chosen to export my colours as a new colour layer, meaning that I’ll be able to work closely with the colours in Adobe Photoshop afterwards.
If you have created your colours as a new colour layer you will see the colour layer in the Layers panel, above your original black and white image layer. The new colour layer has the Color Blending Mode selected by default. This displays the colours in the colour layer overlayed on top of the black and white image layer, creating a colour image effect, but retaining the black and white image information for future editing, e.g. removing dust and scratches.
If you are not happy with a particular colour in your image, you can edit that colour by selecting the colour layer and by going to the Brush tool and painting directly onto the image. Any colour which you choose to paint onto the image will replace the colour in the colour layer. Obviously, you can control the brush shape and size using through the Brushes panel located in the Window menu, or by right-clicking on the image area in the workspace. The colour you are working with can be selected in the Colour Picker, located in Tools, or can be selected from another part of the image using the Eyedropper tool.
Working Files And Your Final Output
As with any complicated images created in Adobe Photoshop, you might want to consider saving a working file for future renditions of your work. Working files can be saved as a PSD or Photoshop document, which will contain all of the image’s layers, including your new colour layer. This means you will be able to edit your image in future.
For your final output however, e.g. for printing or publishing online, you will want to consider exporting a JPEG or TIFF image. Generally I would follow the logic of JPEG for digital display, and a flattened TIFF for high quality print applications.
A colourised and restored photograph of my grandfather Pete from when he was a child. The photograph was scanned from a very small contact print which was stored in a family album and already blurry and out of focus. Having scanned the photograph, I removed all the dust and scratches, boosted the contact as the original was faded, and then colourised the image. I have however elected to leave the ‘arrow marks’ at the top of the image — which were probably created by the darkroom equipment — because they add to a character of this poor quality, but nonetheless sentimental old image!
Final Thoughts
I do hope you have found this guide useful, and do feel free to share with me the results of your own experiments with Adobe’s Colorize neural filter on social media.
It will be interesting to see how these tools develop over the next several years and whether we will reach the point where image colourisation is automatic and requires relatively little human interaction. At this stage I have mixed feelings about the prospect, for I actually really enjoy the process of restoring and colourising old photographs. However, the ability to automatically colourise old images opens up the process to everyone, and will mean more photographs being restored and shared. Whereas at the moment so many old photographs are just sitting there in peoples albums or in boxes in the attic gathering dust because the technical processes for image restoration and colourisation are niche specialisation!
If you would like to learn more about colorising old photographic images, don’t hesitate to check out my class Beginner’s Guide to Colorizing Old Photographs in Adobe Photoshop (available on Skillshare and Teachable) where I look at Adobe’s Colorize neural engine in more detail and explore how it can be used in an image colourisation and restoration workflow. And to compliment this class, I have also got a class Beginner’s Guide to Retouching Old Photographs in Adobe Photoshop (available on Skillshare and Teachable) where I explore Adobe Photoshop’s tools for restoring old photographic prints and negatives. Both of these classes are available as a Photo Restoration in Adobe Photoshop bundle on Teachable.
