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Reducing less than a pixel 3

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flyzzzzz

Vendor
Mar 28, 2006
21
US
I have a bunch of 1 pixel lines at 120 resolution! I would like to reduce them in width and height by 10%. I understand this cannot be done in ps as it does not recognise % of a pixel.
My thought is to save as a tiff. open in Illustrator create a reverse mask, that can be enlarged 10% or place a thin out line.
As you can see I don't have a clue! Any idea's?
GAry
 
What is 120 resolution?

If you want the line to be 10% less, increase the resolution of the image 10 times and then trim the line back down to 90% (or nine pixels thick).

The idea of making a sub-pixel image in a pixel editing program seems odd. Perhaps if the application of this thin line was explained, a better idea may be offered.
 
Or change the resolution to 133 with resampling turned off? I have to admit, I'm a bit puzzled by this one too!
 
!00% better feedback is needed!
I am interlaceing animation for lenticular so, the resolution is specific and cannot be changed. The reason for making the lines a little thinner is because the end process is for screenprinting. Screenprinting as opposed to digital printing has a certain amount of bleed, if I can make the lines a little thinner without changing the centre point of each line I will be able to create a better transformation from one movement to another.
Hey there Blue how are you mate, you helped me last week, thanks
and thanks too Jim
GAry
 
The only option here is to improve the screen so that your resolution can be improved.
 
I understand what you are saying Jim And it makes total sense from an in general perspective. One of the things that I noticed in the inner glow tool (Illustrator) was when I asked for .10% px inner glow It did not refuse the command! Only, I did not see where it took the action, amybe that is because it was around the edge of the box. Is there a way i can highlight the lines and give them an inner edge glow, my reasoning is that if I can create that glow on the edge of the lines I could print it out as a half tone.
GAry
 
Could you select the lines and use the Free Transform or Transform/Scale and then pick the percentage of height you need?

If the lines are vectors you should get "transform path" on the Edit menu.

Using OSX 10.3.9 on a G4
 
Research sub-pixel rendering and realize that if you want thinner than 1-pixel lines, you are going to get semi-transparent 1-pixel lines. Whatever trick you are finding in Illustrator is going to produce a bitmap semi-transparent 1-pixel line that might actually smooth out to cover 2 or three pixel lines.

A device that prints with pixels cannot print anything smaller than a pixel.

You need to increase the resolution and the linescreen to pull off anything sharper/thinner than your current 1-pixel lines.
 
First of all I would like to thank all those participating in this debate!
It seems that it is not possible at the moment to "split the pixel"JIM, I tried to hairline a glow on the edge of my pixel, and the whole thing became transparent, as you mentioned.
Keith in ps pixels come in different sizes that are defined by the resolution i.e. if I am using a 30LPI animation and am working at 120 resolution then, I will get four frames every 30th of an inch. If I set the resolution to 360 then I will get 12 frames per 30th of an inch.
You know what JM and Jimo! the reason I take my ps docs into Ilustrator is to enlarge them by %'s of a pixal because in ps I end up wirth 2 pixels NOW what if I was to reduce to 98% as well as have a layer grey at original size then merge them together, will that give me a border?
GAry
 
Code:
pixels come in different sizes
An interesting concept but one which I feel is incorrect.
Pixel size on a computer monitor remains the same hence the comment about it being impossible to have less than a pixel's width displayed.
120 pixels will always take up the same amount of space on a given monitor. Increasing the resolution will increase the image size on screen in proportion.
Hard printed images, whether they be screen printed or machine printed are quoted at dpi (dots per inch) and can vary from a few dots per inch in the case of a dot matrix printer to thousands of dots per inch as in the case of high quality photographic images.
120 dpi does sound rather low for screen printing.

Keith
 
You Know what mate! I don't really know how it works but it does, I do my interlacing in ps and thats how I do it and it works! go figure. I mean you probably have a very logical point.
Wait a mo' If the print image size and the pixal size are constant and the resolution increases the image size on screen proportionally that means there are more pixals to the screen size picture, eh nice one thanks keith
ps the screen printing I do is on t-shirts where we set a dot size at 60 dpi and print the film out at 1200 dpi
GAry
 
Ok, I've done lenticular graphics before (although I did it digitally rather than screen), so let's see if I understand what's going on here:

1: Your finished image is made up of vertical lines, each 1px wide.
2: Because of printing inaccuracies, it's nearly impossible to get the lens to line up perfectly with the lines, so you want a slight "gap" between each pixel.

If that's the case, then try this:
1: Work out how much smaller the gap should be compared to the lines (let's say, 10%)
2: Enlarge your image 10 times (1000%) using "Nearest Neighbour" resampling method.
3: Create a new Photoshop document, 10px x 1px, transparent background
4: Draw one white pixel at the right edge (or whatever colour you want the gap to be).
5: Select All, Edit > Define Pattern... and give it a name.
6: Go back to your original image, and go to Edit > Fill...
7: Choose "Pattern" and find the pattern you just made.

You may need to adjust the resolution (with Resampling turned off) to match your finished printed size. These graphics are very tricky to get right, but the results can be amazing once you get your settings right.
 
Wow, this site has some great minds!
1st. what is the printing problem-not enough ink down/weak visual color. if I give pressure to the squeegee to get a liitle more ink through the screen, a bleed is created where the ink will print slightly wider than the actual width of the pixal.
The films I am using to make the screens are positives, they are black and greyscale. Idealy what I would like to do is make a duplicate of the layers in a 80/90% halftone transfer them to illustrator at 100% along with the color serations for the positives. Enlarge the halftones to the size needed, reduce the seperations to say 95% and then merge the seps with the half tone version which i think will give me a half tone edge to each of the lenticules.
By the way Blue,It's not that hard to set up and as you say "it can be amazing"
I do not totally understand your way but, will give it a try tonite
Thank you mate
GAry
 
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