hello, your image is not parallel, and even if it was, you shouldn’t have troubles working on it. You just have to be precise while setting up the axes :
I have an advice, if you stick to the images with small axes, it won’t be very precise. do it at first to get a rough adjustment, then pull out the handles to gain in precision since you know where you want to go… (Having built a rough shape matching the image, to help for adjustment) like here :
Hello paul, thank you for your testing, I have some problems when imitate your template.
The first one is, what’s the different between same color handles (green and red)? I have checked Tirmble Document, but seems like they didn’t explain such detail thing.(or maybe I simply missed it.)
I only know the length of handles would affect their sensitivity and maybe affect scale when dragging.
2.After did a quick modeling, basic shape is fit to image, detail not though, if I want to sculpt more detail, what can I do?
that’s because your building is not a simple box, it has many different elements that lie on different planes. you’ll have to edit your model. you may want to check tutorials
for your color question, that is because we need two lines per axe to determine the vanishing points (where the two of them will meet)
One good tip is that you can leave the match photo scene by orbiting, start to push/pull a face (or any modification) and once you started it you can click on the photo match scene tab and go on editing while having the picture in the background again