Grey dotty background that I can't get rid of

[boopino]

Hello, this is my first visit and post )

I have exhausted combinations of trying to do this with no avail, somebody please put me out of my misery!! I am trying to print from illustrator cs2 after: Here's my process:

I scan my B&W line drawing sketchbook into photoshop

I tidy sketch up in there to make sure no pixel gaps in order to use paintfill tool later, and also use magic wand tool to delete background then paste image into a new transparant page.

I save it (tried PSD, bitmap don't really understand which is best here sorry for my ignorance)

I open it in Illustrator, click on it and use live trace button.
I then paintfill it in happily as I go.

I then need to place it onto a standard template that it needs to be printed on/with, so I click and drag it across. All looks well and good, however,when I print it there is a very tiny grey dotty box I can't seem to get rid of around the image. If I open the image in photoshop it shows a white box where the grey dots have printed but even when I delete it it still prints grey dots. Aararggh!

I have learned Pshop and illustrator via online purchased tutorials, which although good obviously have gaps and I have no one to ask! Please help me!!

Kind regards
Emma aka Boopino

 

[MarcusStringer]

I think your image has a 1% dot in the background.
If it's greyscale or RGB or CMYK do the following:

Open it it Photoshop.
go to

Image>Mode>Bitmap

When the next window comes up, enter this information
where it says Output make sure it says 600 pixels/inch, also make sure the method says use 50% Threshold, press ok

Save
Place it back into Illustrator.
Print it
Are the dots still there?




Marcus

http://www.midlandtypesetters.com.au

 

[boopino]

HI Marcus
Thanks for getting back to me. I tried what you said but when I get to it, the bitmap option is greyed out - or when I try with new images where the bitmap option isn't greyed out, no box comes up to put in what you tell me to input. Arrghh!

Still stuck!
Thanks though, I got really excited then as it sounded so like it was going to work!

 

[apepp]

...you need to be in greyscale before you enter/convert to bitmap...

Andrew

 

[apepp]

...did you originally scan this image in line art or rgb?

...if the dotty background is appearing after the live trace function is made then it can either be the original image has a small percentage dot the tracing function is picking up or your printer is printing white/highlight areas with a small percentage dot, this can happen with color management enabled in some cases...

Andrew

 

[MarcusStringer]

Yeah Apepp's right, I forgot to mention that.

If the image is CMYK or RGB to begin with , you have to convert to Greyscale first.

Image>Mode>Greyscale

Then straight after

Image>Mode>Bitmap

Then follow the above steps

Marcus

http://www.midlandtypesetters.com.au

 

[boopino]

Thanks so much and Hi, however, I did what you said but still no box comes up to enter threshold info, and now the image is grey with scattered grey dots in the background.(more like photocopy debris dots than the uniform dots I am finding on print)

I think because of my lack of knowledge I am doing something in the process incorrectly.Perhaps if I start again but with the right settings, saving correctly? I must be doing something wrong and have no clue what!

When I scan in original line drawing what should I be scanning it in as?

When I clean it up in pshop and go to erase the background using magic wand, delete, and click and drag onto a new transparent page the best way and what should I save it as?

When I open it in Illustator and hit live trace is there anything I should know or be doing?

When I go to paint fill it, is there a way of just highlighting the object not the whole big 'box' around it (maybe this is where my dots turn up?)

And finally, THANKS FOR STAYING WITH ME IF YOU ARE STILL READING!! when I go to move clik and drag it to my template for printing (which is mysteriously always dot free) is there anything I should be doing ??

Hope you can help
Kind regards
Emma

 

[apepp]

Hi Emma...

>>> When I scan in original line drawing what should I be scanning it in as?

I take it the line drawing is a pencil (mono) sketch, generally with these you can scan in lineart (bitmap) mode at very high resolution (600dpi to 1400dpi at actual size) if this is destined for high end print work. This often requires tweaking the the thresholds in your scanner software to maintain the needed detail. The result is pure black and pure white (white is transparent in bitmap mode).

Another way is to scan in color or greyscale at high res as above and tweak it in photoshop using levels, curves and/or a threshold layer. This can often yield better results with maintaining detail than scanning straight in lineart bitmap mode, this depends on the original you are scanning.

In your case I would either place the image in Illustrator in grescale and trace it as is. Here is a link that will explain the functions better:

http://www.adobe.com/designcenter/illustrator/articles/illcs2at_tweak_02.html

...or tweak it in photoshop first to end up with a bitmap (black and white) this would lesson the work to manually delete the background if it is just a paper grain you are trying to remove. If it is in rgb or cmyk colour at present then convert to greyscale (image > mode > greyscale) and then adjust the levels or curves to make as much of the lines as black as possible and the background as white as possible. Any pixels below 51% grey will turn to white (transparent) when converted to bitmap mode, anything above 51% grey will turn black.

Place the bitmap in Illy and select live trace, try the presets on offer, a good starting point is to use 'black and white logo' setting. Path fitting option is often a good one to adjust in the Live trace dialogue.

Once you have traced it and the object is selected choose to expand the object. You may find the object has some unwanted clipping mask around the whole thing, select it and choose object > clipping mask > release. Delete it and the whole object will hopefully be able to sit on a background of choice and showing through. You can search for clipping masks by choosing select > object > clipping masks, or via the layers palette (sub-layers) manually.

A handy tool in Illy to fill areas with colour is the Live Paint tool (first column, third from bottom in the tools palette). Here is a link showing th basics of it:

http://creativemac.digitalmedianet.com/articles/viewarticle.jsp?id=33066

Andrew

 

[boopino]

Thanks very very much Andrew. I am going out now and will be away until Monday when I can try your fabulous instructions. Really appreciate your time, have a great weekend, Emma )