Posts Tagged ‘matching grain’
Water stains on photo can be restored but some are far more tricky than others.
I was recently contacted by Robert who had an old photo mounted on card. A long time ago it had received some water damage which had since gathered dirt. To compound the problem the surface of the photograph was textured with those horrendous “stipple bumps”. Up close it looks like someone has covered the photo with bubble wrap. This was a surface treatment originally designed to toughen the image for wear and tear. It did not appear to be affected by thumb prints so seemed the ideal Matt paper. Unfortunately it left a myriad of minute channels and troughs for dust and dirt to gather in over the years.
Tackling this image required the use of a variety of techniques from the restoration tool box.
Firstly the image was treated with an FFT filer to remove the texture. (Fast Fourier Transform). “Fourier” is the surname of the person who invented the technique. He came up with a ways of deconstructing an image mathematically and with his calculations was able detect and then remove regular patterns or textures. If you own a digital image editing program you may find a plugin or process that uses this to remove textures.
The image was then converted to a black and white. The uneven contrast was tackled next. Sections of the image were masked out and brightened and treated for tone and contrast to attempt to get a more evenly lit image. Ultimately the problematic sections were lightened or darkened with a soft brush, dodging or burning where needed.
The mans shirt was almost completely remade due to texture loss when brightening. I painted in base white, added noise or grain to it and matched this to the underlying texture of the image with a little blur. The collar and folds on the shirt were shaded in with a soft brush. A similar process was used to recreate the curtain backdrop.
Skin textures are always the hardest to get right. On the right hand side the girls skin and hair took the most time. Robert knew how he wanted the hair to look so we worked through a few edits to get this right, trying shiny hair and partings in various places. The skin also took some time to keep it even without losing too much facial form. Robert had paid a premium price to get the result you see and his girl friend on Valentine’s day was over the moon!
This is a follow on post from my original matching grain article a while ago.
This is just one example of how to match grain when replacing a back ground or perhaps any part of an image.
Look at this image, it is part of a man’s shoulder and the background could do with evening out or replacing altogether.
Here I have just selected and deleted the back ground to white. It does not look at all right.
Above a blur might clean up the background. Whilst evening out the background it still does not match very well.
Here I have added some grain (noise) but it still does not match. If I apply a blur to this then we can achieve a better result.
With a slight blur its much better and using the correct selection technique for the original background selection it looks fairly convincing. Using this matching grain technique and varying the amounts of grain and blur ratios and perhaps even repeating the process a few times along with varying the type of noise, we can achieve different patterns of grain to suit nearly every situation.
For a short video on this topic see below.
Ok so know we know a little about Image Resolution and how it might help us with photo restoration.
Lets now take a look at some advanced techniques to help with restoring old photographs.
If you need to restore a photo that comes in JPG format and has had its fair share of compression applied to it and you cannot do anything about for what ever reason, then have to work with what you have. Repairing it can be tricky as the dreaded JPG artifacts and slurred pixels can be a problem. Valuable parts of the image can be lost, particularly when working at finer detail levels.
Let me site an example. Figure in a dress, saved as JPG and the face has suffered a bit from compression artifacts and some detail has been lost. One way to fix this would be to artistically paint in using brushes and dodge and burn tools to recreate parts of the face. This will of course look too smooth. You can add grain as a fix but it doesn’t always work as its looks too uniform or doesn’t match the base image. With a combination of painting on a new layer over the original and trying to clone in some grain from below can help but also if you save out your new layer to a JPG and play with the compression settings, you will find that you can get some very similar JPG artifacts on your saved layer as the base layer. When its pasted back in you can then match the grain and base image a little easier than before.
Image-restore Restoring your photos across the uk