Hi all, I am new to CAD and I am a bit uncertain about reverse engineering from pictures. Basically, I am wondering whether it would be a good idea to modify the pictures of the object I am trying to model before I import them into solidworks to trace the profiles. By modifying, I mean fixing perspective and other types of lens distortions with photoshop (I am using my phone camera).
I am trying to take orthographic pictures, but sometimes the profiles don't match at the points that they should while I trace them. As I've read, some deviation is unavoidable due to perspective, especially in curved objects. Is fixing the perspective/barrel effect through photoshop a viable strategy? Or will it create more problems? (like mess up the proportions of the object or somthing idk).
If anyone has tried anything similar I'd appreciate your input.
P.S. I am taking all the steps I can to reduce perspective distortions, but I'm wondering if there is something else I can do to get proper ortho views with my limited setup.
Question about reverse engineering from pictures
Re: Question about reverse engineering from pictures
How are you going to remove perspective from photos? The only way I know to minimize it is to take the picture from as far away as possible or use a flatbed scanner. I've done a fair bit of tracing photos. Generally I get a reference dimension and make sure the image is square and level. I don't think you'll ever really get rid of it for parts that have any depth to them. Reference dimensions are your friend.
Blog: http://dezignstuff.com
Re: Question about reverse engineering from pictures
I never heard of editing pictures like this, and might be a waste of time, IMHO.
I just make sure the photos are orthogonal to the planes and put a ruler for quick reference, if I cannot use a ruler I measure something as a reference to scale, and chop the photos before importing (in Paint of course
).
If it is for reverse engineering most measurements will have rounded values so you just ignore the deviation on the photos; if it is a organic model, well, you wont be able to replicate it no matter the photo quality (just get close), so no worries.
Be sure to identify the most important measurements in the part - the ones that will make it useless if you do not replicate properly
I just make sure the photos are orthogonal to the planes and put a ruler for quick reference, if I cannot use a ruler I measure something as a reference to scale, and chop the photos before importing (in Paint of course
). If it is for reverse engineering most measurements will have rounded values so you just ignore the deviation on the photos; if it is a organic model, well, you wont be able to replicate it no matter the photo quality (just get close), so no worries.
Be sure to identify the most important measurements in the part - the ones that will make it useless if you do not replicate properly
Re: Question about reverse engineering from pictures
I guess there are some features in photoshop like "lens correction" which can allow you to adjust the vertical perspective of the image inward or outward, as well do other tweaks to make up for the lens distortion of your camera. I stumbled upon this while searching for ways:
Anyway yea, it is somehow good to hear that there is no way to get it perfect, as I was breaking my head trying to figure out what I am doing wrong. I will trust the measurements. The idea of including a ruler for reference inside the picture sounds simple and efficient, yet it didn't even cross my mind lol.
Thanks for your replies.
Anyway yea, it is somehow good to hear that there is no way to get it perfect, as I was breaking my head trying to figure out what I am doing wrong. I will trust the measurements. The idea of including a ruler for reference inside the picture sounds simple and efficient, yet it didn't even cross my mind lol.
Thanks for your replies.