thanks for the reply. i knew if there's something tricky in illustrator there's no way jet won't reply and smash the obstacle with his intelligence. thanks a lot. i have 4gb ram and i3 processor 3.1 ghz. i have intel integrated hd graphics. well when i adjust those valuse in illustrator, AI works fine but the computer hangs and illustrator shows not responding for a moment. after the processing is done, everything goes fine.
i3 processor, 4gigs ram. isn't illustrator too demanding while tracing a sketch?
Moreover i'm getting lotta noise, the corners are not coming as smooth as the sketch. please advise the settings. thanks once again for letting me tap the advanced button to explore that beneath lies my answer
My original sketch http://i.imgur.com/vTtQ9.jpg
the settings i'm using
You really should not even be resorting to autotracing for that image. It can be drawn properly in less time than it took to post the question; far less time than required to answer it correctly; far, far less than the time wasted fiddling with autotrace settings for so simple an image.
Autotracing is not a panacea, and certainly not a miracle. You don't get something for nothing. 'Garbage in / garbage out' very much applies. Illustrator's autotracing in particular includes no shape-recognition intelligence. It doesn't recognize what you intend to be "a corner" or "a circle" as such. Your result is too noisy because that image contains entirely too much noise. The autotrace routine is reading all that noise and trying to draw paths around (or through) it. That's all it does.
An age-old common routine for reducing the noise in an image that is appropriate for resorting to autotracing (which, again, yours isn't) is:
- Open the image in an image editing program.
- Blur it to reduce noise.
- Adjust curves or levels to maximize contrast and "re-harden up" edges.
- Save it.
- Autotrace it.
The inherent trade-off is that the process of reducing noise also reduces detail, because neither a raster imaging program nor an autotrace routine really knows the difference. Basically, those "pre-processing" steps are what some of the settings in Illustrator's autotrace options dialog (blur, threshold) try to do--albeit comparitively crudely and with no direct visual feedback. You can futz around with the autotrace settings and still never get anything as clean as you need.
Autotracing is grossly overused by those who really don't understand what vector-based drawing is all about, and/or are just too reluctant to buckle down and learn to use the drawing tools correctly. It should be used only as a last resort for the infrequent situations in which proper drawing method is impractical. Otherwise, it's just a gimmic; a cheap amateurish novelty; a kid's toy.
If you're thinking "Yeah, but my architectural rendering is going to be much more complex than that! It's gonna have whole walls of hand-sketched stones, not just a single column!", then you need to be looking at properly drawn pattern fills, not autotracing.
If you're thinking "Yeah, but I want to retain the hand-drawn stylistic appeal!", then you need to ask yourself why you feel it necessary for it to be vector-based in the first place.