I was always of the opinion vector and raster will never work together.  I could be wrong, though.  How do you save the file?  It seems you can't save a vector to a raster format can you, so the vector line you import will have to be rasterized anyway?  I don't have cs6 at the moment, and have not heard of this, so I'm curious if it really works as you describe or if it rasterizes the illustrator stuff on import.

You should never "design" your portfolio in Photoshop (I am unsure about CS6, but should still hold true.) A document like a book or portfolio is best assembled in InDesign, while raster graphics and icons are created in Illusttrator, and images are edited in Photoshop. Linking all of the files into InDesign and then editing in their respective program is the best workflow and file size/quality management. And pay attention to CMYK and RGB differences. Doing it your way is just creating more work for yourself with compatibility issues.

photoshop handles PDFs really well these days. CAD>PDF>Photoshop. It's a ridiculously fast workflow depending on what you are attempting to do.

But when you save a PDF in Photoshop vs InDesign/Illustrator, the file size will definitely increase. I would still do CAD>Illustrator>PDF (with preserved layers)>InDesign>Print

I agrea with "curtcram" these are two different worlds, "vectors" in Adobe are there to minimise file size. Off-topic many who cut stencils are disturbed by the fact that when they "vectorise" their bitmaps the result are "vectors" not fit for a plotter -- they plot but the "drawing" is nothing but holes. Couldn't you import your Vectors by drawing them in program made for that and then saving it as Dxf or some other Vector format that you can import ? 

I didn't explain it right. this is my common workflow when it comes to portfolio design: 2D Diagrams and construction drawings in AutoCAD>PDF>Photoshop (for layout,corrections,coloring in diagrams etc.)

When I do this the quality of the drawings and the line-weights are horrible because when a PDF is opened in  Photoshop, the first thing PS does is rasterize the file to make it smaller for editing.

Now this is all happening when I import or open a PDF. But I was messing around with Photoshop CS6 and I found out that you can actually copy and paste (ctrl,c,v not export or import) from Illustrator to Photoshop. When you Paste, it give you options for "paste as"  and you can choose few options and two of them are "Path" and "Shape". When you paste as Path, the copied vector files stays a vector file and you can edit the lines, change stroke,change color etc. as you would in Illustrator.

Now here's the main part, when I change line weight or stroke of that vector line in Photoshop, the lines don't come out as crisp. I was wondering if any one knew why I am having such problem.

I totally agree about using Illustrator and InDesign for Portfolios but I am not good with Illustrator and I have been using Photoshop for years now. I know this question doesn't make sense to people who use Illustrator. I thought the same before I had Photoshop Cs6. Then I thought if I can use PS for same purpose then why not? I don't draw in Illustrator the only reason why I would use it is for the vector lines to come out crisp since its a Vector God in the Adobe Suite.

What better time to time to learn that now. You can hammer in a nail with a screwdriver, but it will take a lot long and have poorer results than if you just used a hammer. Use the tools for what they're made for. It doesn't take too long to pick up on it.

I agree and that is what I am going to do. I actually have a list of software that I wanted to learn in summer (just basics) but I never got to them due to internship and stuff. I will start learning illustrator but I will also try to find answer to my original question.

I don't have CS6 so I can't change strokes, but can still paste as path and shape layer. If I choose to rasterize the path, indeed the line comes out pixellated (not antialiased). This seems to be a bug though, because if I just click the brush tool (pre-CS6 you would select stroke width with the brush tool) and try again, the line comes out correctly. Maybe this is similar in CS6?

For AutoCAD to Photoshop, the best way to get the AutoCAD lineweights is to plot the file into an EPS instead of PDF. The lines remain as crisp as they do in the normal AutoCAD Plots. Then continue with the EPS file in Photoshop.

just tried the eps idea, installed a plotter in ACAD through plotter manager>add plotter>adobe>blah blah blah plot to file

and i printed it, came out super blurry.. it looks like it was drawn with a potato or i guess it looks like some bokeh gone terribly wrong haha.

I'm going to go back to my previous suggestion that raster and vector are essentially mutually exclusive.  When you say 'path and shape' in photoshop, I'm pretty sure that's still a rasterized line.  Even though it has a start and end point, it's not a vector.  Unless CS6 does it different.  The path just makes it a bit easier to draw a line. 

Photoshop doesn't rasterize the pdf to make it smaller or manageable, it raterizes because rasterizing is the only thing Photoshop knows how to do.  You can import the pdf at a higher resolution, then lower the resolution to something reasonable later down the workflow timeline.  Same thing when you copy/paste.  Photoshop rasterizes the line because that's what Photoshop does and it's what Photoshop is for.

Perhaps this helps:

http://pixeltango.com/articles/graphic-design/efficient-expert-tips-to-make-anti-aliasing-your-bitch-in-photoshop/

In a mostly unrelated story, I have been asked a couple times to have a rendering I did put on a billboard.  Basically the client took an image I made that looks great at 11"x17", and pretty good at 24"x36", and they want to make it maybe 5 or 6 feet across.  They send my image to the sign company, who calls me and says it looks like shit (in a nice way).  That's because raster images don't scale.  Ever.  It's just dots of various colors.  So the sign companies have asked me to turn my raster image into a vector.  Vector drawings, because of what they are, scale.  3dmax doesn't do that.  Neither does Photoshop.  Especially with renderings, I want the control of grading tones an whatnot that you just don't get with a vector graphic, so I am not prepared to change my workflow just yet.  Maybe we can get i r give up to make a script or program to turn rasters into vectors, but I still have to go to my original point that rasters and vectors cannot exist together.  Until something comes to light to suggest otherwise, I consider that a fundamental law of nature.

To the OP, this does not help you but maybe it will help your reasoning.  And to Per Corell, it would be nice of you to spell my name right if you're going to quote it.  It's written right above this post so you can just copy it.  Thanks.

as the link loads (which is taking forever for some reason, but i am ready to get blasted with knowledge) i would like to say something...

that personal story you shared was very emotional because i have been in same situations too :D

So far what i do is kill my computer to get highest rendering output i can and send it to the printing company. You can convert raster images to vectors in illustrator's Trace Image function. It doesn't look as good because you lose all the gradiants and fancy material textures

I'm guessing you went ahead with the add plotter>adobe>postscript level 1.

Despite that, if you opened the plotted EPS file in photoshop and it was still blurry, then probably you dint give a minimum resolution of 200 while opening the EPS file in photoshop. Make sure that the layout size of the AutoCAD file is the same size you want for the EPS file in photoshop, so you get the exact lineweights. EPS always works for me!

I generally set the layout in AutoCAD to be in A3, and open the EPS file in the A3 size, and then scale(-it down, I could do A2 if I wanted it much bigger) the drawing in photoshop if I need to.

I did as you said and it worked and i compared it to pdf import and both look same, guess who will start learning illustrator tomorrow :)

Thank you all for you time  

Illustrator or Photoshop both are so good and useful. I am use the illustrator for creating vector or logo designs. Here you can check the some good examples of vector graphic.Compass Vector

"You should never "design" your portfolio in Photoshop, A document like a book or portfolio is best assembled in InDesign" Enough said

Vectors look OK in photoshop too - just keep the resolution at least 300 dpi

I figured i should just learn Illustrator and Now i know basics, enough to do regular cad editing and diagramming. Next is learning how to layout using Indesign with reference files form illustrator and Photoshop.