How to fine-tune the lighting effects tool

[IndiePubber]

First of all, thanks to everyone who's been helping me along with my latest book cover.

As I posted in another thread, here's where I've gotten to with the front (I have the typography in another file and will layer it in when the graphics are complete).

   

I'm at a pretty good place, I think, with the color matching, but the Fachwerk background needs work to make it less one-dimensional and more lively. I'm aiming for the same background effect I had on the first book in the series. Its front cover looks like this:

   

The blueprint background is a vector image licensed from Shutterstock and it came as you see it, with the highlights and shadows already on. I just moved it around behind the heads of my couple to get the halo effect I wanted.

The Fachwerk photo, on the other hand, was evenly-lit, with no variation of light and shadow. I think I can use Filters > Light and Shadow > Lighting Effects to give me some highlights, at least. But I'm having a hard time doing it correctly. I'm able to go into the Light tab and use the blue dot to add point-source glow, but . . .

• How do I locate the light points so they're at the right position behind the models' heads? Yeah, I see the boxes with the X and Y axes, but I have no idea how to find those numbers in relation to the layer above.
  
• How do I make the glow radius smaller so I only get the light I want? Every time I try, even when I turn the intensity way down, it over-lights and overwhelms the whole background.
  
• I'm wondering why the Bloom tool options box keeps coming up, when I didn't select Bloom in the first place. I wouldn't mind experimenting with it, but when I try to use the sliders or enter a parameter, nothing happens.
  
• Would it help if I chose Transparent Background in the General Options dialogue? Would that create a new layer so I can move the light around on the Fachwerk image and put it where I want it? Or would that be "Create New Image"?
  
• Are there settings in Lighting Effects where I can create negative light, so to speak, and selectively put parts of my background in shadow? Or would that be a different tool?
  

Maybe I should ask if this Lighting Effects is even the best tool for the job. I had a bit of luck with Supernova, but it was tricky trying to eliminate all the rays. And even then, it's too star-bursty.

Thanks in advance for any pointers you can give.

[sallyanne]

You may beable to do something with the lighting effects under light and shadow. As long as you use an image that is flat.
Do you have just the back ground? I'll see what I can do and let you know then. If not there might be something in GMIC.

[denzjos]

Create a path around the background and press 'Enter' (the path turns into a selection). Hide the path. Copy the selection to a new layer. Apply the 'Filters / Edge-Detect / Edge / Roberts' filter to this new layer. Set the layer mode to 'Soft Light' and the layer opacity to 75% (or 100%).

   

[rich2005]

The bottom, room image, could probably do with a bit of a tweak.

Gimp 2.10 / Windows 7 ?  I do not know if you can get a gmic_gimp_qt plugin for Win 7 Maybe an older gmic version  

The light glow flter

   

[IndiePubber]

(Yesterday, 07:50 AM)denzjos Wrote: Create a path around the background and press 'Enter' (the path turns into a selection). Hide the path. Copy the selection to a new layer. Apply the 'Filters / Edge-Detect / Edge / Roberts' filter to this new layer. Set the layer mode to 'Soft Light' and the layer opacity to 75% (or 100%).

When you say "around the background" do you mean around the three places where it's visible behind the heads? Or should I make the whole area above the yellow band smaller for the time being, so I can mark a path around the couple? What should I expect to see in the new layer?
Thanks!

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(Yesterday, 06:05 AM)sallyanne Wrote: You may be able to do something with the lighting effects under light and shadow. As long as you use an image that is flat.
Do you have just the back ground? I'll see what I can do and let you know then. If not there might be something in GMIC.

Here it is with just the background.
   

Here it is with the couple layer in reduced opacity, if that will help. My main difficulty is getting the glow on the background layer, at the right position behind the heads.
   

I'm interested to see what you have in mind. I'll need the steps to reproduce it, of course. I am still very Junior.

[IndiePubber]

(Yesterday, 08:25 AM)rich2005 Wrote: The bottom, room image, could probably do with a bit of a tweak.

Gimp 2.10 / Windows 7 ?  I do not know if you can get a gmic_gimp_qt plugin for Win 7 Maybe an older gmic version  

The light glow flter

Yes, it installed just fine. I take it I'll have to shut down GIMP and reopen it to make the new tools available? Where should I look for them when I do?

[denzjos]

Copy the background to a new layer and lighten this layer using 'Colors / Exposure'. Then, add a mask to that layer: right-click on the new layer and select 'Add Layer Mask / Black / Add'. Select the brush ('Paintbrush' tool) and paint a white dot over the area you want to brighten (large size; hardness and strength set to 50%). Use the brush repeatedly on the same spot until you are satisfied with the result. If it is not yet bright enough, you will need to lighten the new layer further using 'Colors / Exposure'.

   

[rich2005]

(Yesterday, 07:34 PM)IndiePubber Wrote: Yes, it installed just fine. I take it I'll have to shut down GIMP and reopen it to make the new tools available? Where should I look for them when I do?

It is a plugin for a 64 bit Windows, if gmic_gimp_qt installs correctly, as with any new plugin, you need a Gimp restart for it to register.  Find it bottom of the Filters menu.  It has all sorts of filters, there are examples here https://www.gmic.eu/gallery/

If no good for your present project, then for future projects.

600+ filters are a lot to consider, there is a search function to narrow requirements down.  Example.

   

I did a try out with a Win7 (64 bit) VM / Gimp 2.10.24 / gmic_gimp_qt 2.99 and that worked.
A note for Gimp 3.x users, apply any layer effects (fx) that are there. It can stop a gmic effect showing.

[IndiePubber]

(Today, 06:21 AM)denzjos Wrote: Copy the background to a new layer and lighten this layer using 'Colors / Exposure'. Then, add a mask to that layer: right-click on the new layer and select 'Add Layer Mask / Black / Add'. Select the brush ('Paintbrush' tool) and paint a white dot over the area you want to brighten (large size; hardness and strength set to 50%). Use the brush repeatedly on the same spot until you are satisfied with the result. If it is not yet bright enough, you will need to lighten the new layer further using 'Colors / Exposure'.

This sounds promising. Thanks. 

I haven't had the chance to try it yet, but do you think I could get the shadows by making another layer and darkening it up?