This writeup assumes you have sufficient knowledge of AutoCAD's
- plotting utilities
- lineweights
AutoCAD to Photoshop
Converting AutoCAD drawings into Photoshop rasters is a useful tool since it can help turn simple line drawings into an effective poster presentation.
Preparing AutoCAD drawings
I should state immediately that no amount of photoshopping will turn a badly drawn 2d into a more interesting means of communication. Sections, plans or details should be prepared in the same manner that you would for plotting i.e. by considering lineweights and dstances appropriate to the scale of the printed drawing. Also, do not neglect colours, drawing extent and centering.
However, if you plan on making a poster, I would suggest against including the standard bottom right corner text box. You will later be able to add this information in photoshop in a much more interesting way.
Plotting to a pdf or an eps file
The boring part: AutoCAD is a vector program - lines contain extra information then what is read by the eye. For example, if a straight node is accidentally broken it contains three nodes, as opposed to two. This information is lost when the image is printed on paper. Plotting 'to file' enables vector information to be translated into raster information... which can be subsequently used by photoshop. So you would need to effectively send the same information you send to your printer to a digital file.
- For Adobe Professional Users
Select the Adobe printer in the dropdown printers menu. If you are using AutoCAD 2004 or 2006, plot a you normally would, paying attention to paper size and scale. A window will prompt you to specify the name and location of where you would like to save the file.
If you are using an earlier version of AutoCAD, such as 2000, you will need to specify the save location from the first tab before you hit the 'Plot' button. Note that files are saved as PDFs.
- For non Adobe Professional Users
You will need to create a virtual plotter. This is a very efficient tool, especially when, like me, you're lazy and plot from Modelspace.
From the top menu, navigate to Tools>>Wizards>>Add Plotter...
Bla bla NEXT.
'My computer' should be selected. (This is the default). NEXT.
Choose Adobe, 'PostScript Level 1 Plus'. Well any should do the trick but lets go with this one. NEXT.
NEXT.
A ha! This is the all-important bit. Hit 'Plot to File'. NEXT.
Call your new plotter kohlcass. You must. Otherwise it won't work. NEXT.
Looks like you're done.
Select kohlcass in the dropdown printers menu. If you are using AutoCAD 2004 or 2006, plot a you normally would, paying attention to paper size and scale. A window will prompt you to specify the name and location of where you would like to save the file.
As above, if you are using an earlier version of AutoCAD, such as 2000, you will need to specify the save location from the first tab before you hit the 'Plot' button. Note that files are saved as an EPS.
Opening your PDF/EPS with Photoshop
Find your plot file - well, you saved it.... you should know where you put it! Right-click and Open With.. Adobe Photoshop. A
pop-up will ask you to indicate what resolution you would like your drawing st to. This is an extremely important step, especially if you are planning on transfering you drawing to a ready made background. If your background is an A3, set to 300 dpi, it follows that you must select 300dpi as your
resolution, otherwise you will lose the scale of your image. You should never rescale a drawing layer afterwards... you will lose both your resolution and your scale. We're going for crisp, drawn to scale drawings here.
Takes a while to rasterize... go make some coffee.
Ta da! Rasterisation is complete.... and all you see on your screen is a blank Photoshop checkerboard. This can't be right, can it? Well, since your drawing is the only layer and your lines are probably quite slim, they won't be very visible. So simply add a new white layer (Layers>>New layer, Shift+backarrowdeletebutton) and make sure this layer is beneath your drawing.
However, if you haven't prepared a background already, I suggest you do so now by creating a new Photoshop file. This will ensure that your canvas size is correct. You will then be able to drag your drawing layer (from the first file) onto your new background.
'The fun'
You should then be able to manipulate your drawing as you would a normal image in photoshop. You can select areas in your drawing, using the magic wand tool and create a new fill layer (Layers>>New Fill layer) to express these areas in colour. Posters made using well-drawn technical drawings as a white layer (Right click drawing layer in the Layers Toolbar, Blending options... Colour Overlay) with a dark layer as a background is just one way of improving the readability of your presentation. You can add rendered images of your project or material samples. If you're still new to Photoshop, watch out - Photoshop is notorious for not being the most user-friendly program available, but hey, if you've mastered CAD, this should be no biggie for you.
Photoshop tennis, anyone?