Installation

Unzip Loreal into a folder of your choice. And the Help file with photos. That is all you need to do.
Note that the program generates two temporary files in its installation folder, they are the plugs Undo and Redo.

Beginning

Now start the program and load a file (Fichier/Ouvrir). It must be a Windows Bitmap (.bmp)
Obviously you will be loading an image with 'ears'

Here is an example of a picture full of 'ears'

The complete image is shown in the main picture, with the enlargement showing the cursor locality.

Buttons:
Undo = > Undo!
Redo = > Redo! More precisely, return to the state preceding the last Undo
Reload = > Reload the original image
Sauver = > Save the modified image
Auto = > See below

Cursors:
Sensibilité: (Sensitivity) The closer the cursor is to zero, the more precise is the program in determining the pixels to be modified. As a corollary more to the right, the more one will have blur.
Rayon: An approximate pixel value of the radius typical of the field stars.

Three operating modes

The clever click!:
As an example, take the star in the top right corner which has pronounced 'ears', position the cursor (which takes the shape of a cross as it moves over the image) approximately in the centre of the star and click.

And the job is done! With reference to the sensitivity setting, on Black and White images the value will be generally low (10/15 maximum) if not the image may be heavily marked and you'll have to try again. With colour images on the other hand the sensitivity will have to be a little higher so you need to try different values.

The radius is useful here, it is the range of the action of correction starting from the point you clicked on. 

This seems pretty easy, so I click a few stars on the left without changing the parameters to see what I get...

Click click click click...... pretty good, eh?

Good but if it is a globular cluster how do I deal with that?

Don't worry! There are 3 operating modes

Thus there are two more of them to see!!!

Working on an extended area - replastering :-)

It is possible to work on more than one star at a time, provided they are approximately the same size and appearance, and the background is reasonably smooth. Drag a box around the area to be worked on, then Click.

 

... And it's done!
And you can apply the same method to a globular cluster!

It might not be a complete solution, but worth a try.


NOTE: That in a group of several stars, small comet tails can appear in the place of the ears. Most of the time it will be enough to click on the star concerned to make it disappear (the tail, not the star!). If that does not work there is always the Undo button (or Alt+Ctrl+Del).

You might say: " But there is a zone on the right core, darker than the remainder, which is full of small black holes. Perhaps I could fool the program into thinking that they are black ears and correct this defect a little?"

Well, let's give it a try, with sensitivity increased.....

 

  A large rectangle with sensitivity set at 44. OUCH! - at this setting it's obviously overprocessed.

 

The same one with the sensitivity of 1!

Not bad, perhaps try again with sensitivity 5 and that might do it.

So below is the result of our progress so far.

AVANT

APRES

 

Auto Mode:
You will remember that there is a third mode. It is the Auto mode, here one tries to correct the whole image in one go. It is a bit like other graphic filters, it is necessary to test and to start again and sometimes never find the best settings, either because one is not patient enough, or because the image does not lend itself to the treatment. Here are some pointers towards finding the best settings:

 

The algorithm in the program affects the areas of the image according to their signal-to-noise ratio, that is regulated with the vertical cursor. The higher the setting, the more the zones of weak S/N will be integrated, and vice versa.
The default setting when the program is run is a value representing closely the signal of a star with black ears. Modify it according to the situation.

Don't change the sensitivity.
In Auto mode, the radius is not directly related to the stellar diameter. Without going into detail, suffice it to say that the image is scanned line by line analysing as it goes. Roughly speaking, the cursor radius gives the scan increments.

Care is needed for images with large zones of strong S/N (cores of galaxies, bright nebulae...), a small radius can create artifacts in the brilliant parts. In this case it may be preferable to treat by replastering or individual click.

The same image as previously treated in Auto mode with the parameters above:

Enough is enough. Experiment with your own images and enjoy!!