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I shoot in studio. Many of my photos have softboxes inside the frame. In post-processing I need to remove them - for example make background fully black. When softbox has white, I set Adjustment brush exposure to -4 EV to make it black (+Highlights to minimum), but it becomes only gray. I need to apply same under exposure brush for 3 to 5 times to get solid black background - a time consuming and silly work. Sometimes this does not help.

How could I achieve this easier? If I have sliders with more extreme values (for example brightness correction with 8 or 10 EVs) it will be great. Any plugins for this?

Edit: Same issue when I make photos on white background and the black part of softbox is into frame. Whitening the black makes it only gray, because more than 4 EV are needed.

Example photos:

https://s28.postimg.org/cpropyfqx/lr_extreme_1.jpg

https://s28.postimg.org/fxw63020p/lr_extreme_2.jpg

https://s28.postimg.org/mczsdey49/lr_extreme_3.jpg

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In my opinion LR is not the instrument for such tasks. Better use photoshop, gimp or any other editor.

You can try to use adjustment brush and set exposure to -100%. Then duplicate the brush, then again and again. But I am not sure about the quality which you will receive

  • Yes, duplicating “darkering” brushes is an option, but I am looking for better approach. I do this so frequent so I need to speed up this process as much as I can and to avoid huge amount of Adjustment brushes on the photo. Any plugin for this? – joro Jan 16 '17 at 12:06
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    @joro, I personally have no info about such plugins. And let me say I again: for such tasks will be better to use image editing software like OS, Gimp and so on – Romeo Ninov Jan 16 '17 at 14:14
  • I know PS could solve this easy, but I like the workflow in LR. If I start working in LR, export partial results in PS and continue working in LR, quality of the photo is reduced and this is a time consuming. Because such a basic thing as painting with solid black or white. – joro Jan 20 '17 at 21:04
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    @joro, the idea of adobe about lr is to have editor for photos tuning. such action (paint with colour) imho go outside of above target :) – Romeo Ninov Jan 21 '17 at 13:05
  • Painting in LR could go outside LR scope, but my question is about that range for exposure correction is not enough for some situations (cameras, etc). And changing exposure is not out-of-scope for LR – joro Jan 23 '17 at 9:16
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I'm thinking three things:

  1. You're looking at the wrong sliders
  2. Your photos are off from where you need them to be in the first place
  3. You're shooting in JPEG, which doesn't give much freedom in post processing compared to RAW

About the first point: the "Highlights" slider controls, well, the highlights of the photo, i.e. how prominent the bright areas are (and in your case it will probably have little to no effect on the background). The "Exposure" slider controls the exposure similar to what you do in the camera (but only as far as the dynamic range captured in the photo allows).

Look at the "Blacks" slider. It controls the black clipping. It should have a range of (-100, 100) and sit at 0 by default (if it has a range of 0 to 100, you're probably set to using older process version; look at "Camera Calibration" and set "Process" to 2012). The further you move it to the left (in the negative direction), the lighter colours are clipped (i.e. set to black in the output picture); the further right you move it, the more black is "lifted" (i.e. what normally is black becomes grey). Take a look at the histogram in the Develop module. In its upper left corner there's a small triangular button. Hover over it and it will show you with blue dots on the original picture which areas are clipped to black. You can click to toggle it so the indication stays on. While it's on, drag the "Blacks" slider to see what happens with the histogram. Pro tip - you can drag areas on the histogram itself.

About the second point: I don't know what your setup looks like, but start with increasing the shutter speed - the farther away your background is, the greater effect this will have on darkening it (which however might not be very achievable with a softbox).

About the third point: if you're shooting JPEGs now, switch to RAW - RAW gives you much greater flexibility in post processing, alleviates the need to care about white balance and tolerates greater mistakes in exposure.

  • 1. I use exposure slider with value -5 EV, shadows with value -100 and highlights with value -100. But these values are not big enough to make white sections of softbox totally black (RGB 0,0,0). The dynamic range of my camera is so big that these setting are not enough. Please note I need to make the corrections on part of the photo (adj.brush), not the whole image – joro Jan 16 '17 at 11:40
  • 2. The exposure of my photos is correct. If I move back, the white will get darker but the main subject will be also darker, so this is not an option I want. Changing shutter speed in studio does not cause same darkening effect as changing it when shooting on natural light. – joro Jan 16 '17 at 11:48
  • 3. I shoot in RAW and this does not solve my issue. Contrary, if I start shooting in JPEG, the issue could disappear. RAW files have wider dynamic range (higher degree from white to black), so changing parts of the area from white to black needs more f-stops than doing the same in JPEG and more f-stops than there are available in LR. – joro Jan 16 '17 at 11:57
  • I missed the part that your softboxes are bright, sorry. In this case post process might be able to help, but if it was me, I'd think of something else to try - e.g. black or near black backdrop. – K. Minkov Jan 16 '17 at 12:04
  • The backdrop is black. – joro Jan 16 '17 at 12:09
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A plugin wouldn't be feasible, as all lighting obstructions would be different, and content detection is quite sophisticated.

If you want black or block white then it's reasonably simple to do in LR, but you may have to do the same work on top of each other.

The reason being block black/white is effectively heavily over/under exposed, so all you need to do is set exposure to the maximum/minimum in your adjustment.

There are two useful tools in doing this:

  • If the obstructions are at the edge, drag in gradiants setting expsoure to +/- exposure. Stack these on top. Quicker then using a brush, but not as refined.
  • Adjustment brush, mentioned in previous answer. Use a bigger, harder brush as you can, so don't worry about the feathering.

Useful hint, top right hand side, you have the histogram. There's a couple of triangles. One is for lowlights, another is for highlights. Click these on/off, to ensure that the complete area is black/white.

Like everything, the more you do the quicker it becomes.

  • I used to do all these things (except harder brush). They worked fine for my previous camera, BUT my newer camera have so huge dynamic range that all slider extremes could not turn the white to black (or black to white). I will try harder brush and write back if it will help. – joro Jan 16 '17 at 12:33
  • @joro it does sound more LR than the camera.. is the brush 'painting' based on sensititvity? – Crazy Dino Jan 16 '17 at 13:02
  • Hard brushes do not solve the issue – joro Jan 17 '17 at 10:43

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