Remove Colour Stains from an image using Selective Colour and Levels adjustment

[GarethCallan]

Hello Folks

 

I'm still on Affinity Photo trial, so I hope I can get a prompt answer to this.

 

I'm no expert on Photoshop, but when re-touching/restoring old documents or old photos there is a technique that uses Levels and Colour Range to remove stains and blotches that affect only part of the image.

 

I have a photo that has a yellow stain on part of it - but it is NOT a cast that covers the entire image (I know how to deal with that - it's much more straightforward). The same issue occurs with brown stains/blotches on old documents.

 

In Photoshop, you'd add a Levels adjustment layer.  In the dialog box or panel, that adjustment layer automatically has a Mask Layer (doesn't seem to in AP)

 

When you select the Mask Layer in the Levels panel in PS, you have the option to Refine>Colour Range   This means that you can select which colour range to apply Levels to by using a Mask Layer.

 

You sample the colour of the stain using the dropper, then use the 'fuzziness' slider to adjust the range of colour in the sample and feathering to subtly integrate the adjustment.  Once selected you can then adjust the levels of that colour range to reduce the impact on the image. 

 

How can i achieve the same in Affinity Photo please?

 

Many thanks for your help and support.  

 

Gareth

[R C-R]

All adjustment layers in Affinity Photo have a mask. You can 'paint' on them with black, white, or grey to hide or show where the adjustment is visible, & by how much.

[GarethCallan]

Thanks for your answer, but it doesn't really help me.  I want to know how I can make that colour range selection, refine the edges, get it into a mask and then use Levels to adjust.

[Scungio]

Hey, do you have a sample image you can post that has an example of a stain or blotch? I know of the technique you are talking about in Photoshop but Affinity may just have a different way to get the same result. If you can post an image that I can download via dropbox or google drive or whathaveyou I can probably figure out a way to do it and post a video tutorial. Or try to anyway, I have 5 days off, with two remaining and getting a little antsy so a distraction would do me some good :)

[toltec]

Thanks for your answer, but it doesn't really help me.  I want to know how I can make that colour range selection, refine the edges, get it into a mask and then use Levels to adjust.

Not "refine edges" that is the process of improving hard edges or extracting around hair. You need to blend the edges in so nobody notices. Nothing worse than an obvious patch.

 

Every picture is different but this is the way I have found works best.

 

First of all, (well, first after you have made a duplicate of the layer) is to select the stain area approximately, I would say the selection brush is best but do switch "snap to edges" off. Paint it so it is a bit smaller than the stain all the way round.

 

Press "Q"  that will enter you into Quickmask mode.

 

Using the brush tool in white, selectively blend the edges of the stain into the background. Quite a large brush is best and I would suggest an opacity of 5% and a Hardness of 0% to start with. Build it up, don't try to do it in one go. Paint in black to correct any mistakes.

 

When you are happy, or think you are, press the Q again to get back to normal mode.

 

Press Ctrl U to bring up the HSL adjustment. Or click on HSL Adjustments in the adjustments panel. The shortcut is worth remembering as it is such a common adjustment.

 

Adjust the sliders to suit. 

 

If the mask is not quite right, i.e. not blended enough or in the wrong place you can easily edit it.

 

Just click on the HSL Shift Adjustment layer and press the Q again and start blending.

 

If you find the selection area marching ants a bit distracting, you can switch them off by going to View, Show Pixel Selection and un-ticking it. Don't forget to switch it back on again when you have finished or you will get confused next time you select something.

 

It takes a bit of experimentation but if you get it right nobody will ever know.

 

If the stain has a hard edge, like where a liquid has dried out, you will need to remove that with the clone tool or one of the healing brushes.

[John Rostron]

You might like to try Nik Viveza. The control point technology allows you to select an area by colour, which you can then modify accordingly. I have used it to remove a shadow from a flower petal.

[GarethCallan]

Hey, do you have a sample image you can post that has an example of a stain or blotch? I know of the technique you are talking about in Photoshop but Affinity may just have a different way to get the same result. If you can post an image that I can download via dropbox or google drive or whathaveyou I can probably figure out a way to do it and post a video tutorial. Or try to anyway, I have 5 days off, with two remaining and getting a little antsy so a distraction would do me some good :)

 

Scungio - you're a legend.  Thank you so much for your help and thoughtful support.  Top man.  Fanstastic to have folks on the forum with deep knowledge of the product and good quantities of common sense and logic too.  So kind of you to help me out so generously.  You've made an Affinity Photo purchaser out of me.

[fullmetalchrono]

I'd like to know how you resolved this problem Gareth as I am also stuck with this.