I have a series of scanned drawings in Tif format. I want to import
them into AutoCad and then edit, scale etc. When I use the Open command
and look in the directory containing the files, I cannot see them as
AutoCad wants to see dwg or dxf or dwt extensions.
As you can see, I have a very steep learning curve in front of me and I
would appreciate any help that is out there. Thanks in advance.
What version are you running? Easiest method is grab the file in windows
and drop it on drawing. Some versions under insert have raster image
option and even more have ole object. Choice of method will vary. Raster
images do not lend themselves to scaling very well since they are
basically a finite number pixels and zooming in will show the individual
pixels, whereas cad is vector based and precision is much higher
Ken Rock wrote:
Many thanks for your prompt and full response.
I am running Version R14.
I can copy a section of the scanned drawing and paste it into a new
AutoCad drawing but I am not able to edit it or scale it, etc.
Is it like having to use OCR in a scanned text application?
Regards, Ken Rock
In the meantime, instead of being insulting, are you aware that the
image command is not available in all versions? That is why I gave a
generic method of drag and drop and asked for his version. In the mean
time, what he is trying to accomplish won't work with the image command
since what he really wants to do is convert the image to a vector.
So just grow up and don't think you are so smart because your stupidity
well he said he was using R14... Image command is part of R14...
and I was wasn't being insulting, like you, I was answering his question...
talk about stupidity... your picture must be next to that word in the
Get a life...
After *JG* sat on the keyboard
the following *crap* showed up here:
Look at the sequence of messages. When I gave him my advice I did not
yet know the version he was using. When he indicated that it was rel 14
I admitted I wasn't familiar with that version. Since there is no
command structure to drag and drop, it IS the easiest method of
inserting a raster image. I also said that there were other methods that
would depend upon his version. But you decided to label my responses as
"poo" and "crap." If you don't consider those insulting, you truly are
as stupid as I stated.
We bring in alot of images, and occasionally have to redraw them, but
I've found the align command to be useful in getting a scanned image to
a correct scale. Usually we are adding to an existing drawing, i.e. a
site plan, and need to scale the image to true scale to add some detail
from the image. Not perfect, but pretty close.
Now ya'all play nice.
I am not experienced at version 14. (skipped that one, company I was at
used 10 then I moved to a company that hand-drafted until they went with
low end drafting software and finally came over to cad on 2000)
When you drop the tif on the drawing, are there no grips on the block?
If there are grips you should be able to drag and stretch. Precise
scaling may not be possible.
As to your comparison to ocr, it is slightly. When you scan the sheet,
you have multiple dots, but your ocr interprets the dots as lines and
compares the lines to its "dictionary" of how letters look. The problem
with cad is worse. If your tiff has a resolution of 200 dpi and was
drawn at 1/8"=1 foot then each dot is .48 inches, and you cannot resolve
between dots, so precision should not be set realistically closer than
1". Any closer precision would be you fooling yourself. Of course 1/4"
scale or scanning at 400 dpi would allow 1/2" precision. Combining
original at 1/4" and scan at 400 dpi allows 1/4" precision, BUT you
still have to consider what the original resolution was when the
original was created. For example: created on an HP inkjet plotter circa
1998 and plotted in color has a limit of 300 dpi, if plotted in Black
and White could be as high as 600 dpi (or significantly lower). Pen
plotters had step increments with worse numbers. Also lines have their
own thicknesses which would create their own tolerances. As a result I
would never use a scanned image as a scaleable item, and would only use
it as an illustration.
Ken Rock wrote:
I really appreciate the effort you have made to explain the problems
involved in trying to convert the scanned files.
An architect friend who has been dragged screaming and protesting into
the digital world has been sent some drawings which he wishes to modify.
Rather than redraw them, he hopes to scan and modify them. He has had
a course of lessons in AutoCad and is running AutoCad 2005. I assumed
that if I can open the files on an older AutoCad 14 system, he should
have no problems with his system.
Is it possible to convert these scanned files? Surely the problem is an
old one with, hopefully, a practical solution.
Again, thank you for your thoughtful response.
Briefly, no. Not with any degree of precision or trustworthiness. Have
him ask the original drafter to send the files. If he can't convert them
to 14, take them in an alternate format and download acmecad convertor
to convert them to 14 (assuming they're not 2007 format) or go to
autodesk web site and download their convertor. Acmecad works better
IMHO but Autodesk is the only one who can convert 2007 files. If 2007
you may have to convert to an intermediary format and then use Acmecad
to get it back to 14.
Use 'Insert' 'Raster Image' 'Attach', then navigate to the tif file.
'Scale' it either on insertion or after insertion. It might be very
small on insertion, so take care to find it! 'Insert' should be one of
the headings across the top of your screen.
You cannot edit the image other than to scale it. you can draw over it
and create your own copy, but that's all.
Remove NS from address before email reply.
Once I had a complex bracket to insert into a CAD file. When it was
inserted, it was static and could not be modified. What I did was just
trace over it and then I had my CAD drawing which I could modifiy any way I
Indeed so, but I find that I need to choose the colour of the trace
lines with some care, so that they can be seen on top of the image.
Then, of course, there is the need to alter/scale the lot to match the
real object. Can be a deal of work involved for a complex item.
you call them scanned drawings. is it not possible to get some sort of
cad file format from the people who produced the originals (which were
I have seen lots of threads for raster to vector conversion, and it
seems to be a lot of work. I always wonder if it would not in many cases
be ultimately easier to read the drawings with your EYE and draw them.
If they are very complex drawings, you won't be getting control over
layers or line types or any PRECISION to speak of from an image.
so I wonder, why this way?
if you just need an image, why bring it into CAD at all?
caveat, a MAP for a site plan makes a great deal of sense. sometimes.
Many thanks for your input.
No, it is not a silly question and indeed, if it were possible, the
answer would be copies of the original CAD drawings. Unfortunately,
this cannot be. From what you and JG have written, perhaps the only way
forward will be to redraw all of them.
Regards, Ken Rock
If I am understanding what I read it sounds like you could use a raster
to vector program. We use a program where I work so that I can scan in a
drawing of somekind and the use the raster to vector program to trace
the scan. Then you can save that trace as a dxf. most of the time it's
very uneven but it saves a lot of time.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.