To remove shadows and grain from the background we can chose a threshold for values of transparency and of opacity when using the "Color to Alpha" tool in Gimp 2.10:
Simply drag the sliders until you are happy with the result. On a white background your image will then look like this:
Alternatively you can make a colour selection with the select by colour ...
You can clean the picture first, for instance using Levels:
the big peak on the right is the original background. This shows that the background is not pure white. If you use C2A without preprocessing, you have to aim for this color.
The white handle is dragged to the left (left edge of the background peak), so that most of the background becomes pure white....
Theoretically lens distortion can be reversed if the distortion is one to one i.e. it doesn't mix to any point light from several points of undistorted image. Of course some resolution loss can occur when the image is resampled. Somewhere new pixels are interpolated to stretch an area and elsewhere an area can be squeezed to smaller number of pixels.
To be ...
Choose black as the foreground colour
Select the Brush Tool. In the tool options underneath the toolbox, set the Hardness to 100%, and size to something like 10.
Use the Fuzzy select tool (Magic Wand) or the Select by Colour tool, to select the blue area
Do Edit > Stroke selection, choose the "Stroke with a paint tool" option. Click Stroke.
Do Select > ...
When you use the 0..255 range you are likely in a gamma-corrected image. To compute the resulting color, Gimp converts the 0..255 value to "linear light" applies your composition formula, and reapplies the gamma correction. So the composition is really applied with darker colors.
However, since Gimp 2.10 you can work in gamma-corrected or "linear" light. ...
To expand on @BillKerr comment, "Lock brush to view" scales the brush with the zoom: the ratio brush size/window area remains constant, so that at high zoom factors you don't get a brush that is bigger than your image window. In effect this shrinks the brush as you zoom in. If course if you start with a 3px brush, at 3800% zoom it is 3/38=0.1 pixel and is ...
You map it in the System Control Panel - globally or per application. The Wacom settings dialog may look different depending on device/operating system.
This is the Mac CP, using a Wacom Intuous
And here's Windows 10 showing a Wacom Bamboo Touch settings.
Using Filter>Distorts>Polar coordinates
I assume the real goal is to map the image to a sector, and that the path is not really necessary.
If we apply the Polar coordinates filter to a square image:
We get this:
The final image is the same size as the initial image
The whole image is wrapped on a full circle (360°)
The height of the image is mapped on a ...
If you use Nikon's own ViewNX-i [available for free from Nikon] it can
Link edited to hopefully now always find the latest version
a) batch convert to jpg [Export, set parameters, Convert]
& more importantly …
b) make a much better job of knowing what the camera's settings were supposed to be than any 3rd party app.
On recent Ubuntu (since 18.04 at least, may be earlier) they made the Python support in Gimp optional. You can tell if your Gimp has Python support by looking at the bottom of the Filters menu that should have a Python-fu submenu alongside the Script-fu one. If it's not there you are missing Python.
You can install the Gimp python support using sudo apt ...
You can use the Warp Transform tool in GIMP
It's located here on the toolbar shown below, or you can press W to select it. Then just paint with it to move and warp the pixels. You can change the size of the tool using the [ and ] keys. When you have finished hit Return / Enter to commit the warp.
It works best if you don't go too crazy with the tool, ...
Do a wand select of the background
Shift click in any isolated areas that you want to remove (loops in "O", "P"...)
Select>Grow by one pixel so that the selection bleeds over the pixels at the edge of things.
Color>Color to alpha and remove the white
Result: put over contrasting backrground:
(yes, there is a small miss in the sharp ...
You can use Image > Print Size, to change the PPI without resampling the image, i.e. while maintaining the same size in pixels.
In the Print Size dialog, you can either set the PPI you want and GIMP will work out the print size, or change the physical print size, and GIMP will calculate the PPI.
Yes, you typically duplicate the layer, apply the weaker setting to a layer and a stronger setting to the other, then add a layer mask to the top layer and fill it with a black-to-white gradient:
After you have created the gradient on the layer mask, you can amend it with Levels or Curves to adjust the transition.
For pixellation, you would use several ...
You have tried to take a color which is impossible to show in RGB. GIMP has at least a possiblity to select impossible to display colors by Lightness-Chroma-Hue. LCH easily allows combinations which are undisplayable in RGB monitors (=need RGB numbers beyond the available range 0....255) Those combinations are shown as bright magenta.
Reduce Chroma (=...
What you have is "banding". This happens when you don't get a transition between areas of similar colors. A tell-tale sign is that the histogram look like a hair comb:
Very often this is due to color loss which is itself induced by round-off errors that occur rather quickly when you work with only 8-bit per channel.
Since you are on Gimp 2.10 you can ...
"Overall" is not a good parameter to compare. We would need to make a table comparing specific features.
But I will give my 2 cents. Perhaps these are not a big issue. Perhaps they are.
One specific limitation is "Integration". There are competent tools for every application adobe has. Vector drawing, photo editing, video editing, compositing, printing. ...
I will not discuss in depth any technique, because you have already some good answers. I want to talk about something else.
All straight lines of the real world must be straight at the image too.
Nop. That is an illusion.
Stand in the middle of the longest hall in your house, or, if it is safe in the middle of a small street.
If you look to one side ...
You can't because the Tab is reserved for the GTK library (Gimp's UI is based on GTK). For some details see here.
This explains why you can't assign that combination in the keyboard shortcut editor, the editor doesn't see that key event when you enter it.
Even trying to bypass the editor and enter something like:
PSP has adjustment layers. They stay functional if you export as PSD and open the image in Photoshop. I guess it's the most remarkable and wanted property which isn't implemented in GIMP.
In addition you get many advertisements. PSP has this and that useful, but when you use it you see it's somehow limited. For example you open a RAW photo. No problem ...
You have 3 grayscale layers (R=G=B). You have to reduce them to their color component (R, G=0,B=0), (R=0,G,B=0),(R=0,G=0,B).
You can do this for each layer with Color>Components>Channel Mixer, in which you will for instance set the Red layer to 100% of its red component and 0% of the two others. When this is done your layers should be black and red, black ...
This is one easy way if you have some beam images taken in otherwise black darkness. I used your example beam:
This works in any photo editor which has layers and blending mode ADD. GIMP is one of them. I used Photoshop, which doesn't offer any advantage in this case.
I added 3 copies of your beam as separate layers with layer blending mode=ADD. I applied ...
Stop using Photoshop for the 3D part. There are better options out there, and free. I will dive into it later.
Study the wonderful and profound paper I made about projections. https://www.otake.com.mx/Apuntes/Imagen/EnviromentMaps/ The basic idea is that you need to understand that putting a 2D image into a 3D sphere is a bit complicated and you need to ...
The crop tool has an option to lock the aspect ratio (or the absolute size , or the height...). You click Fixed, select Aspect ratio and enter an aspect ration in the form W:H:
Using the icons at the bottom of the Tools options, you can even save this as a tool preset, and reload it for later use...
This is because your letters do not all have the same width. In particular the "I"s are narrower than the rest, making the lines that contain then narrower. So either
use a fixed pitch font
create a layer per character
use the on-canvas edit dialog to set the spacing of specific letters (mostly increase spacing before the "I"s and before the letter that ...
300 dpi means probably your image must have 300 pixels per inch when the image is shown in its intended size. Another way to say the same is "the image must have resolution 300 pixels per inch"
Dpi as a term is from printing. There it tells how big are the smallest dots in a print process, but I guess your client tries only to ensure the images have enough ...
The simple technique
Use the Curves tool.
If you look at the image histogram:
The hump (1) is a peak frequency of dark pixels and is your text
The hump (2) is a peak frequency of light pixels and is your background
No pixels beyond (3) because your background is rather dark.
So with Curves, you make a diagonal between (A) (everything darker will be pure ...