I am using inkscape for vectorzing b/w images for laser cutting.
the problem that i have is that whenever i use "higher res" images as a source, a soft transistion of the source image between black and white will end up in very complex vector paths (examples will follow later in jpgs). Of course ther is the option to manualy delete que points but this is a very time consuming task and is frustrating if i delete one que point too much if you know what i mean .

So this is an example of the source image:
https://i.postimg.cc/pdmMc6ry/t0.jpg


And this is an example of the b/w outcome which will carry on to vectorization nometter what threshold i use:
https://i.postimg.cc/6qgvRS8R/t1.jpg


To claryfy my desire: I`d like the soft transitionto be a hard line and not a complex one.

So can you think of any tool/brush to minimize the complexity/detail of the b/w transition?
If a 3rd party app is required i am also greatful for your advice especcialy if it is freeware.

I hope that you can understand what i am having troubles with and i am thanking you in advance for
your input!

If you want a more smooth transition between black+white I first take the image to GIMP and have a good play with the threshold to adjust the amount of black versus white areas. Then apply a Gaussian blur filter, export to PNG and autotrace in Inkscape (GIMP can generate SVG from every selection BTW):

Cheers

certainly the best option is to prepare the image in a raster program that reduces the number of colors and softens the image if you don't want grain.
The bottom image has been so treated here, the top one is all in inkscape using the settings shown, deleting the midtone scan, then hitting it with some repeated simplify (ctrl L) and then for the final making all the segments straight.

trace settings mode tab



And options tab note that these don't show in the preview but have a large effect on the result

Even using the straight to one bit color that you are using in your post ( I didn't invert) the multiple scans grays is still a better option than threshold. (Using simplification and straight lines for the last in both series again)

WOW, YOU ARE AMAZING! THANK YOU!!!
I have only just started playing with the "suppress speckles" feature and this is allready a huge advancement.

That being said, i have to admit that i have not entirely understood everything you posted.

I just wanted to express my gratitude a little bit for now and we can go into details later i hope.

Vectorizing an image is not an automatic process at all, the best conversions take a lot of work and at the experienced level no two versions are going to be even close to each other. At some point it becomes a matter of style even if the tools are all the same. Polygon has a lot of skill and I can tell his method will eventually yield a very different result from mine. And he'll probably do it faster, too!