Photomatch Problem

dermotcoll

Hi All

I am trying to do my first photomatch. A client has asked me to make a bed similar to the one she saw in a website. I am trying to do a dimension takeoff from the drawing to get it modelled. This is my first attempt at photomatch and I have watched alot of videos online to understand the process. I think I have followed all instructions but for some reason the axes will not line up properly for me to draw the model acurately. WHat am I doing wrong? My monitor is very lucky to be alive at this stage. I have tried numerous times to get this but have failed each time. I attach the picture for your advice.

Bed Project.skp

Gaieus

I cannot do it for the life either. Most probably the photo has been cropped (or manipulated any other way) which will jeopardise any attempt to get a decent photomatch of it (this is one of Goole's most important warning about photos to be matched)

thomthom

That looks cropped all right. (Rare to get a square photo anyway)
And there seem to be a significant of lens distortion.

dermotcoll

Thank god - I thought I was going bananas - it is a pain in the a** for me as I am guessing at dimensions now!
My blood pressure was rising too - which isnt good for me at the minute! One of you guys might have had to ring "911".

Thanks for the feedback guys -as usual you are great!

DavidBoulder

I would just make some assumptions about the dimensions and model it from scratch.

But if your interested in learning one approach to uncrop photos, here is an old link of mine. Your photo doesn't have a lot of vertical vanishing, so won't work so well for this.
http://www.sketchucation.com/forums/viewtopic.php?f=15&t=10895&hilit=+crop&sid=5ba75feb83dea26a56080dbab7c89e97

I want to see this technique on CSI show so they can figure out that the murder was cropped out of a photo, and then they can find the negative to identify him. Actually when I first search fro techniques to uncrop photos, or look for other alterations (e.g. person dropped in from elsewhere); one interesting technique looked at distortion of the shape of the eye to look for flaws.

By the way, cropping is ok if it is symmetrical, but then again if you didn't crop it how would you know. Some camera sensors (probably worse in cell phones) are not in line with the center of the lens, resulting in slightly cropped images right out of the camera. (while not truly cropped, the optical center of the scene isn't the geometric center of the image (as if it had been cropped).

Gaieus

Maybe an updated link to that old post (in case it didn't work):
http://forums.sketchucation.com/viewtopic.php?f=15&t=10895

And yes, I do remember that old topic just have not practised the suggested technique myself.

dermotcoll

Sorry guys but i did not understand one bit of that. I know nothing about photography and I was lost very quickly. Can you point me in the direction of articles to help me understand this better. It would be very good to know how to do this for future images. Thanks for your help.

DavidBoulder

The simple answer to only use MatchPhoto on images you think are not cropped.

In your situation with a cropped photo I see three options.

Have someone who physically can stand in front of that bed take a photo for you
Have someone with access to that bed or spec sheet for you measure the bed.
Just guess on some measurements and model from scratch (how accurate it needs to be depends upon what you want to sue it for. But if you make the assumption that it uses a standard twin mattress then you should be pretty close.

dermotcoll

Sorry David

I will only find out if they are cropped if I try to photomatch them. I am not technically competent in photography and the image was emailed to me by a client - from a website download. I have modelled it by guesstimating the dimensions. I plan to make a similar bed for the client and she wanted it as close as possible to the image. It was my first attempt at photomatch and I was getting very frustrated at not being able to achieve a good vertical line position when my horizon points were very accurately positioned. Thus the request for help. I have reread your original post on the topic and I just cant match what you are saying to what you have done in the images with the lines. Sorry for not being able to understand this thus my request for further direction on learning more about the subject. Thanks for the reply.