hello dear friends, I need serious clarification. I’m interested in realistic scenes but with the inclusion of objects or 3D effects. Could it be called motion traking? but at the moment I don’t want to make a video, but some pictures, for example with a hole on the floor. I have read many things on the Internet such as the blam addon which later became fspy, camera traking. but what am I looking for? what should i study? I do not understand anything any more… I will give you some examples:
I was just watching this video other day. Haven’t tried it yet, but I believe this technique can be applied to other projects
https://www.youtube.com/watch?v=2-_xLCOqWQs
but this is only for the inclusion of objects, which I have just learned how to do. But for the effects or to transform the floor or the meshes, how do you do it?
(this is my test to insert objects)
I recognize “hole in ground” image from CGMatter https://www.youtube.com/watch?v=P7OpmpE8xTc Have you tried that on a different surface? For example, creating a crater on your notebook (laptop) and dinosaur in it.
I’m not able to do it, I also found the video of cgmatter, but he speaks very fast, I wondered if he breathes !!! 
It is the same process for both motion tracking and cg inserted images into still pictures. Just motion tracking is more involved. If just doing still images you can study the lighting in the image and place them to match in your 3d object so the lighting matches. fspy is a great addon to be able to do this easily and get the camera info positioned correctly and save time. The dinosaur looks pretty spot on for the lighting. Next is if you can find an hdr image that matches the lighting close enough.
This is an older version of blender but the same applies. And Tutor4U is a little slower with his tutorials to follow and see what he does.
He always speeds his videos up but with the magic of youtube, you can slow it down 
Now that you have brought this up I might give it a go as well to see if I hit similar issues that you experienced or if I am successful?
I was playing around with motion tracking earlier in the week but due to the type of video I was trying to track I was unsuccessful. That’s due to there being alot of camera shake.
I was able to do that , but I do not like it, it's a ???. I can't memorize everything and above all make changes so as not to be addicted to videos???. ok I give myself time to learn ?
I understand, but between talking and putting it into practice is completely different. the video you sent me is just for adding items, i am able to do this. thanks anyway
I did it!!!
Well, it’s hard to memorize all steps. Better way of learning is to understand what every single node in that setup do.
In your attempt, I would add more noise cause road is much smoother than crater and also put an HDRI or crank up the power of sun lamp
weks, you did it following CGmatter’s video? Okay, now will you come to my home and explain everything? Joy Im kidding, so more noise…ok I’ll try tomorrow, but the hard thing is to personalize it, to create something else…thank you for your support and for doing the same.
Nicely done. The computer looks very realistic.
VFX is the keyword for what you are trying to do. The concepts are the same for video and still image.
I haven’t heard that one yet, or my God, they’re getting bigger. Wow.
Thats Awesome Francesca! Love the cupcake in the last image! I will see about doing some tutorials on VFX 
If you do motion tracking of stills you need some information about your camera. Lens type, f-stop, digital sensor, etc. All these things you need to enter also in Blender (and yes you can).
But grabbing stills from the internet, this becomes a problem. Blam is a tool, which helps you to define some of these properties. Like focal length and location of the camera!
Blender has also a feature, called motion tracker, to track motions. For this to work you need to add many, many trackers. The more the better. Abobe premiere has also a feature like this, but the placement of motion trackers is done by software. But not always handy, because you need contrast rich key elements in your scene.
Professionals, use infrared marker on bodies and things.
In your case, the road as an example. Is difficult to track because of road the texture. Which gravel stone in the road can you track? To study these things. It’s better to choose a movie with distinct features, which will help tracking the stills in a movie.
You can use BLAM, to find out (using a single frame in a movie) the camera focal length.
Also shadow can be a problem. Where is location of the sun …
mamma mia how complicated!!! I’ll try to understand better, but you know they’ve upgraded the addon blam with fSpy?