Is there a way to remove a gridded paper background from images?

[rebeccal38686413]

I regularly clean up a bunch of images drawn on gridded paper.  (not my drawings and can't change the paper)

I would like to remove the gridded background.

1. I wondered if there is an option to select a section of the grid and ask PS to delete the background that matches the selection.  I think this would remove parts of the image though, that are drawn over the grid.  Maybe there's a sensitivity adjustment? 

2. I am okay with deleting the background/moving the linework onto a new transparent layer etc. and in the past I have generally done this then used levels to fade the grid and manually cleaned up what is remaining, but this process fades out the line work too much so I need to go back over it and it is verrrrrrrry time consuming.

3. I'd be grateful for any suggestions or ideas for alternative methods, I use photoshop in a very limited way and am aware I know about 2% of it!

4. Section of picture for reference, I am usually working on a PSD and can't show whole image for confidentiality reasons.  

Thank you.

[Per Berntsen]

The Spot healing brush set to Content-aware works quite well for this particular image.

This took me about three minutes.

[rebeccal38686413]

Thanks Per, did you go over each grid line with the spot healing brush?  The drawings are typically really large and very detailed and there are a lot of them, so I was hoping I could find a series of actions that would remove the grid fairly quickly and accurately without compromising the linework.

[Per Berntsen]

Most of the lines were removed by clicking and dragging in one operation, but some of the dots had to be removed individually. I have no experience with this kind of work, but I have spent may hours removing dust and scratches from scanned B&W negatives, which this is similar to.

You will probably find that the spot healing brush doesn't always produce a good result. You can then try to drag the opposite way, and/or working on shorter segments of the grid lines.

In difficult areas you may have to use the clone tool, and you can also try the Remove tool. (grouped with the spot healing tool)

I doubt that there is a faster way to do this, but maybe someone else can suggest something.

[rebeccal38686413]

Thank you

[kevin stohlmeyer]

@rebeccal38686413 use the new Remove tool. Bing bang boom done. Took all of about 20 seconds.

  

[kevin stohlmeyer]

@rebeccal38686413 keep in mind this was a complete rush job - if I had reduced the brush size and kept it isolated to the dotted lines, the results would improve.

[rebeccal38686413]

Thanks Kevin, I might be missing something - because I am not sure how this really differs from just selecting what I can with the lassoo and deleting or using the eraser?  

Ideally I wouldn't have to go over all the lines - the images are really large and there are a lot of them. It'd take me about 40 hours to do all of them!

I'd like to select an area of the grid and ask PS to remove the same.  But I don't know that it can distinguish the drawing from the background enough. I have tried the new tools (remove background, generative fill and the remove tool) but can't find anything that really works with this kind of image and background so far.

[kevin stohlmeyer]

@rebeccal38686413 that level of automation is not available in PS. This is probably the best option.

The difference is less mouse movements and also you can overlap areas with gray/transitional colors and those areas will preserve. Selecting and deleting wont work in areas with gray.

One thing that can help is to uncheck "remove after each stroke" and then use the shift key to click between points to draw long straight lines.  Shift-click all the lines then hit Enter/return to apply remove all at once.

[kevin stohlmeyer]

@rebeccal38686413 not sure I understand why the remove tool did not work given my example above. I drew over the entire image including the background and the AI was able to distinguish that I wanted to remove the dots and preserved the image itself...

[rebeccal38686413]

Thanks Kevin, I need to learn how to use the tool properly - I will give it a try. Thanks again.

[Stephen_A_Marsh]

As an alternative, I quickly looked at "global" filters:

• FFT, 3rd party by Fixel Algorithms
• Median
• Dust & Scratches 
• Smart Blur
• Surface Blur
• Neural – Photo Restoration, halftone removal 

I I wasn't happy with them as too much detail was lost.

Others may have more patience to explore further.

Edit: I did consider setting up a template to make selections either in a grid or just slightly larger than the individual dots using a pattern fill. This would create much better filtering results with minimal impact to detail. There was some skew to the sample which would likely be too variable to account for, but may be worth looking into, perhaps placing a vector mask template or such.

[rebeccal38686413]

Thank you Stephen for taking the time to do this, I appreciate it.

[Chuck Uebele]

I think your best bet is what @kevin stohlmeyer suggested. I too don't know why the remove tool doesn't work for you -can you explain? 

One thing that could help automate this is if the drawings are all the same size and the grid is in tje same place. You could create an action for the remove tool, then run it on the other images. You might want to keep a template file with which you could line up the grid.

I did this when I was stacking photos and had some sensor dust. I worked very well. 

[rebeccal38686413]

Thanks Chuck for the suggestions, re the remove tool - I think I need to read more about how to use it.

[c.pfaffenbichler]

Could someone of you please check whether you can apply the Remove Tool to a path via »Stroke path with brush«? 

[kevin stohlmeyer]

No - not an option. Been discussed as an Idea on the forums but currently not possible to stroke with Remove tool.

[c.pfaffenbichler]

Thanks, @kevin stohlmeyer , I have to look up that Feature Request. 

[c.pfaffenbichler]

@kevin stohlmeyer , I could only find this »Idea« on the issue 

https://community.adobe.com/t5/photoshop-ecosystem-ideas/add-the-remove-tool-to-the-list-of-stroke-p...

and it seems kind of under-discussed. 

Do you remember the approximate title of the thread you were referring to? 

[PECourtejoie]

I'm interested as well if there is another thread. I voted on the one Christoff pointed at.