PP merging two pictures together

[munkey]

Ok all im sure this has been answered before but i was just thinking since ill need it..

What is the best way to merge two pictures together? I.e. a tripod shot of same aperture and settings but with different shutterspeed. Guarantees the exact same composition with different highlights.

Now the question is say i take a picture of a car and an overexposed background, and do the same to expose the background correctly, what is the method to fuse the two pictures together? Layers? How?

Right now im just tracing the car from the correctly exposed picture and pasting it directly onto the one with the nice background. Looks quite fake. Someone experienced in this field.. help out? Layers layers blending ??

[catchlights]

if you shoot the car at the same location,
one expose nicely for the car
one expose nicely for the background
load two image in photoshop in same doc in two layers
erase one layer with bad exposure of the car or background
so you able to see only good exposure of the two.

this is the principle, and in photoshop, there are many ways to skin a cat.

[munkey]

Is there no better way to do this?

This method will leave the edges very jagged right?

[Redsun]

it wont if you put the hardness to 0%