How can I erase partial image in a layer

Discussion in 'Digital Darkroom' started by kmac, May 19, 2021.

  1. I'm working in Photoshop to add sun beams to a B & W landscape. I've added them successfully but I've come up against a brick wall trying to erase unwanted beams. The procedure I'm following is to set the brush tool to black, set opacity to 50%, set brush size to 300px and set hardness to zero percent. These seem to be the standard settings according to several tutorials I've been watching.

    However, it is not working for me, it just adds paint to the image, when it is supposed to have an erasing affect. Also, in my CS4, I've found that the only way to get the brush to appear is by merging the layer first, without merging, only the little "can't do" black circle with diagonal line through it appears.

    Has anyone done this before ? I'd be thankful for some guidance to get this sorted out, it's the last step to finish the photo and it's a little frustrating that I can't finish it off perhaps because of an oversight, which I wouldn't be aware of anyway.
  2. Are you using a layer mask? It sounds as if you are painting on the layer itself, rather than on to the layer mask.
    digitaldog likes this.
  3. I did try a layer mask but that failed to produce positive results as well, everything I've tried so far has just left black paint on the image. I suspect I might be doing something wrong with the layers but I don't know what. I may have them out of order perhaps. This is the first time I've used layers and the manual doesn't say much. I know about clicking on the layer before working on it, I do that, but still the same result with the brush.

    I will try a layer mask again and see if I can detect something I'm failing to do with it in order to get the brush to work as an eraser instead of a "painter"

    I'm also aware that in the tutorial videos, it was done on RGB color images whereas mine is B&W, so I scanned the neg again in 24bit color. This brought up colored sun beams, which are then desaturated fully to make them B&W, but still the brush didn't do what it was supposed to do.
  4. "How can I erase partial image in a layer?"

    With the eraser brush?

    There are many ways to skin that cat.
    • Using a lighten or darken only blend mode.
    • Rubbing through one layer to reveal another layer using the eraser brush.
    • Cloning a blank area over the beams.
    • Using the healing brush.
    • Changing the 'brightness' of a lower layer and partially revealing it with the eraser.
    • Using the burn tool on a low opacity to gradually darken the beams (probably the worst option)
    It doesn't cost anything to give things a try, and you might learn a new and useful technique.
  5. digitaldog

    digitaldog Andrew Rodney

  6. It's much better to use a layer mask (if you can get it working properly) than, for example, using the eraser. The process is reversible, that is, if you accidentally remove too large an area, you can just flip the paintbrush colour and paint the lost area back in. Once you have removed something with the eraser, it's gone unless you start faffing around with the history brush or whatever.
    kmac likes this.
  7. I wasn't sure how to word the title of the thread so I just used the word "erase" copying what others were saying on the internet. It's just metaphorical I suppose.

    In your list of alternative methods, I've tried the more obvious ones but none worked, however, "Changing the brightness of a lower layer" rings a bell. I'm required to click on "Soft light" in the procedure before I even get to the "erasing" part, but how many times, or how many layers need "Soft light" I'm not sure, it seems to be discretionary, and it's difficult to know if it's directly related to the Brush Tool doing it's job correctly to "erase".

    Cloning is out of the question because there's no areas to clone from, the whole image is covered with sun beams, and until some are "erased", cloning just won't/can't happen. I'd rather do it the Brush Tool way though, set to black, zero hardness, etc. It's a bit of magic I don't understand but it works for others, I just wish it would work for me.

    You've given me some ideas about the layers I can mull over and work on, hoping to arrive at fixing the brush problem. I'll keep working on it.
  8. I haven't yet set up a layer mask for a second time and worked on it as I said I would, but I'll do it today and get back with the results of my feeble attempts. Hopefully I'll get somewhere with it this time.
  9. You can either erase the layer directly using the eraser tool (not the brush), or paint using the brush tool on a mask. If you choose the latter, you have to select the mask icon next to the layer by clicking on it before you start painting, otherwise you'll be painting on the layer itself.

    One obvious advantage of doing it on a layer mask is that you can always paint parts back with white if you have gone too far with it.
  10. I've just found out why I haven't had any luck with these layers to date. I didn't have the "Layers/Paths" panel up, I was doing it in the "History/ Action" panel, so of course everything was just showing as "history" and not working layers. All that was working was "Image-Open" and "New Fill Layer", after that, layers and masks would come up alright, but no work could done on them.

    Realizing I was working in the wrong panel came from watching videos of layers in Photoshop and I noticed the panel was different to mine. So I ended up clicking on "Windows" up the top and went down the list, found "Layers" and checked it, bingo I now have the correct panel to work in with all the right buttons for layers and masks etc.

    I should be ok now and I wish to sincerely thank all posters for their help and ideas. The value of Photonet, it's incredible.
  11. It's a sobering thought that Photoshop is a very powerful piece of kit, but also hugely complex and with plenty of traps and false trails for the unwary. Looking back over my own experience of learning the programme (and I'm still only really scratching the surface) I can remember many occasions when I've "hit the buffers" with a perplexing problem like this. Finding the way through is all part of the learning curve.
    ericphelps likes this.
  12. For a long time I avoided the "complexity" of Photoshop by using just the simple tools such as the Healing brush, Lighten & Darken, the Clone tool, and Cropping. This made me pretty lazy as a beginner thinking I didn't need to know much more, for what I've been doing with my images. But now of course, there's more to learn and I'd better pull my socks in Photoshop if I am to broaden my skills.

    In all my searching, it never occurred to me to search for "Adobe" sites ... durr I was under the preconceived impression that they, and the Photoshop manual don't tell you much. I was wrong, Adobe explains everything one needs to know about layers and masks, and a whole lot more stuff, they have many tutorials available on the net fortunately.

    I only needed to type "Adobe", then type the required subject after it.

    I got tutorials such as this one ... - (On the right side of the page there's more tutorials to click on.)

    Here's an excellent video I found ...

    These have improved my learning curve quite a bit, and with all the time and effort I've spent sorting out how to do sun beams, I'm at the point where I can now do them with my eyes closed. That's what it takes, practice, and clicking on buttons you were too afraid to click on .. they don't bite lol
    rodeo_joe|1 likes this.
  13. A quick click of the Edit>Step Backward option is such a big deal?

    I use the eraser brush to rub through a layer quite often. Using a soft-edged brush and a low opacity makes the technique extremely controllable, and no less so than painting on a mask.

    The layer(s) are always copied and pasted from the 'original' so no permanent or irreversible changes are made to anything.
  14. Absolutely not, I often use the eraser on a layer for a simple fix when I don't want to bother with a mask. I would tend to use the "painting black / white on mask" method for more intricate stuff. I think it's a good idea to get into the habit of using a layer mask as there are plenty of tasks for which the technique is necessary, for example when using a levels or curves adjustment layer to modify the exposure over a part of an image.

    Also it was clear to me that the OP was trying to use a layer mask, and seemed to want to get the technique working.
    digitaldog likes this.
  15. This is probably a bit of a 'Marmite' example -
    This was done entirely using 3 layers and the eraser tool. Colour version as base layer, and two monochrome converted layers. One monochrome layer was darkened using curves and used to 'burn' some distracting bright areas in.

    I don't think you could get much more intricate than the wilting rose (previously placed in the statue's hand by some unknown person). I also like the way that some stray bird poo has put tears on the statue's cheeks.

    I'm not disagreeing that use of a mask is a useful technique to have under your belt, but I'd argue that simply rubbing through layers is more direct and acheives much the same end effect.
  16. Just off the top of my head, you can create a layer and use the erasure tool. You can set the opacity of the brush at a low percentage so you can effectively brush away the layer a little bit at a time and build toward the effect you want to change. You can change the opacity of the layer itself as well if you feel you've gone too far. Worth a try.
    digitaldog likes this.

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