Hey there, Nuke enthusiasts! Today, I'm going to show you a quick and easy guide on how to attach an object in Nuke for your 3D compositing and visual effects work. Let's dive right in!

Step 1: First, make sure you have the object you want to attach and the scene where you want to attach it open in Nuke.

Step 2: In the Nuke toolbar, go to the '3D' tab and select the 'Scene' node to bring in your 3D scene.

Step 3: Create a 'ReadGeo' node and connect it to the 'Scene' node to bring in the 3D object you want to attach.

Step 4: Next, create a 'Tracker' node and use it to track the area in your scene where you want to attach the object.

Step 5: Now, create a 'Axis' node and connect it to the 'Tracker' node. This will create a new axis in the scene, which will serve as the attachment point for your object.

Step 6: Use the 'Transform' tab in the 'Properties' panel to adjust the position, rotation, and scale of the axis to match the movement and orientation of your tracked scene.

Step 7: Finally, create a 'Merge' node and connect your object to the axis using a 'Copy' operation. This will attach the object to the axis in your scene.

And there you have it! You've successfully attached an object in Nuke for your 3D compositing and visual effects work. Remember, practice makes perfect, so don't hesitate to experiment and explore different techniques to achieve the desired effect. With these skills in your toolkit, you'll be well on your way to creating stunning visual effects in Nuke! Happy compositing!