[Solved] A sort of reverse Match Photo

Working with Andrew Staton (@Quadhurst) on modelling Telegraph and Telephone poles, we’ve together come across an issue neither of us can resolve to our satisfaction.

Andrew has modelled, very accurately, a series of telephone poles in SU, which he’d like to include, in perspective, in an existing photo of a real place which has lost its poles in the past decades, to recreate the scene as it would have looked in the 1960s.

The ultimate output will be an image, for a book in preparation, and there will be many others of a similar kind.

He has tried using the 3D Import tools in Photoshop, and failed to position more than one pole, and can’t get the wires to show at all. They are edges, coloured by material in Styles, and painted grey - solid black shows up far too boldly.

He’s also tried with two poles in a SU model, placed against the image used as a texture on a rectangular face, and positioned the face in relation to the poles so they appear in approximately the correct position. But that involved complex scaling of the individual poles, and won’t work when they are connected by wires in the model (a few wires included for illustrative purposes). We can’t find a way to export edges to Photoshop in 3D.

Below is a screenshot of a SU model, with the positioned poles shown in ghosted white. They are are a bit too big. and placed too near the edge of the road - they should be further back against the house garden walls or hedges, and between the other street furniture.

We’d like to include a row of four poles, the nearer two to line up roughly where the ghosted white images are, but all four aligning in correct perspective with the (real) one still in the original image, much further down the road, and with all wires drawn in grey in SU, included.

Any suggestions for how to do this? Is it do-able?

Here’s the model with four poles spaced 50’ apart (approximately correct for real life in the 1960s) and the image as a texture on a component rectangle in the background.

I’ve saved it back to v2017 so more people may have access to it, but we are working in 2020 Pro, although I have also 2021 Pro.

It’s too big to upload directly to the forum, so here’s a link to a copy on Dropbox:

And here’s what it looks like in SU:

As I was writing this, I realised that one of my problems when trying to line these up was that the perspective in SU isn’t shortening the poles ‘fast enough’ and that therefore the further ones are too tall when see agains the photo - maybe it needs a change in the focal length to a wide angle view in SU?

And I wondered about using a simpler proxy for the poles - the model is quite heavy with detail increasing the number of edges, particularly in insulators. Perhaps just a line for upright poles and cross arms, with guide points at attachment points for wires on the insulators?

Doing that, might it be easier to use the image as a Match Photo, with the proxies drawn on the side of a rectangular box?

But the image isn’t brilliant for that. There are only a couple of items with the possibility of two-point perspective that I can see - the bottom edges of the phone box in the middle distance, and the the near right corner of the image where there’s a small part of the corner of a building.

As far as I know, the image isn’t cropped or otherwise adjusted.

Any advice or help welcome. We have to do this for many images.

I’ve done work like this in the past. What you should do is model the photo with match photo and then insert the poles where you want.

There’s a lot of tips and tricks envolved into correctly model from a photo using match photo, but once you achieve them it’s all pretty straightforward as you just place the poles in the right place in model.

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Thank you for that suggestion.

I’ll take your advice and try that - possibly not until tomorrow, as it’s getting a bit late now in the UK.

But I’ll give it a quick go now.

Copy pasting the poles in caused a BugSplat, but I manage to save where I’d got to, and tried again with simpler proxies.

Let’s see if that will open and preserve the pole locations…

Needed some scaling of the overall poles to get them approximately the right size, then minor adjustment of the green vanishing point to get the size diminution with distance to line up with the pole in the image.

Not bad and with a little adjustment of position will do far better than anything else we achieved so far.

Enough for tonight.

I’ve marked that as the Solution - Thanks again @JQL.

BUT… needs further work tomorrow.

In my Match Photo model, I want to either import or copy/paste the fully detailed poles, but those options are both greyed out. Perhaps it’s too big for the clipboard, but why can’t I import the other model?

Maybe a restart of SU is all I will need? I don’t see a BugSplat report though, which seemed to cause all sorts of menus to grey out last time it happened.

I also tried, just to get my rust out of match photo. I think the sidewalk isn’t parallel to the white house, but it might be to the left single family houses. SKP 2017 attached.

Match Photo Example.skp (6.4 MB)

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That looks like a great match for a picture that’s so close to a one point perspective.

What my eye sees as a red flag in the screen grab earlier is sky and clouds below the horizon line.

Even if you’re in an airplane or looking down hill, you still shouldn’t be able to see sky below the horizon line.

BTW, if you haven’t noticed, the horizon line is one of the things you can grab and move in Photo Match. It changes other things, but I use it all the time as a part of the iterative process.


I didn’t know about being able to move the horizon line, and hadn’t thought about sky below the horizon line being a no-no - two very useful observations.


Have you opened the file I attached? Horizon was a concern as well as making sure NOT to use the ground lines for horizontal planes. Ground is never horizontal.

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Great job using the house on the right particularly given that red axis information is almost nonexistent. The horizon line looks like where it should be. For comparison:

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Thanks! In situations like this, the tip I can share is that you use the red lines to control the blue line. Blue lines are almost always possible to capture.