("what could possibly go wrong?")
Beyond knowing what such things as containers and codecs are, I've never paid much attention to them. Now the time has come and I would like an easy to understand answer, if possible. Here is the situation...

I took a video using a Nikon Coolpix camera. The video codec (as reported by kdenlive) is "H.264 /AVC /MPEG-4 AVC/..." audio codec is "AAC" and the container is .MOV. Using kdenlive I was able to take a clip in Video 1 (the .MOV file), put it in Video 2, rotate it 90 degrees,and put it back into Video 1. All well and good. I have saved the project file, so that I can come back to where I am at.

Now, I don't know how to proceed to create the changed .MOV file using the same codecs that the video started with so that others can also see the video.

Thanks for any help,
MarkN

.MOV is a Quicktime file, but I don't believe that Kdenlive is capable of rendering to that format.

That shouldn't be an issue - you can simply render your video using the MP4 container, which most video players will play. Rendering your project will give you the final completed video.

When you click "Render" near the top, there are several options. If you are going for very good quality, you can probably just choose the "Lossless/HQ" MP4 setting. Don't forget to choose a file location and name. However, you may end up with a file a bit larger than you want or you might want to improve the quality.

If you want more control over the rendering process, you can create a custom profile. I outlined how to do this in a post here:

viewtopic.php?f=265&t=140913

Unfortunately, there is no magic "render with these settings" way to guarantee what the final video is going to look like. It usually takes a bit of experimenting to obtain acceptable quality with a "reasonable" file size.

I've read that MP4 container was derived from MOV, they are very close formats...
You can create a profile with the MOV extension if you like.
And yes Lossless H264 is quite close to what cameras are recording when using only I-Frames (every image fully saved, no image-to-image compression)...

Thank you both. I now understand how to do this.

My best wishes,
Mark