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What Is The File Size Of Bitmap Graphics?
A raster picture saved in Photoshop’s Bitmap colour option is basically hard-edged line art. Anti-aliasing is removed from artwork, leaving a rough, jagged edge. The picture on the left has no anti-aliasing, which implies that the image edge is not softened. The picture on the right is anti-aliased, which means that the computer softened the disparity between the foreground and background colours by blending the harsh edge with an average of the object and background colours.
Image in bitmap format
A bitmap picture (not to be confused with the Windows BMP file format) is a crisp, press-ready image with severe constraints. It can only display as a single colour in a document, and it must be exceptionally high quality (1200DPI, real size) in order to print well. If the picture has a lesser resolution, the edge will become jagged.
In the lack of a vector graphic equivalent, the Bitmap colour mode is often utilised. If you’ve been handed a single-colour logo on letterhead, for example, scanning it and creating a Bitmap TIFF file may be faster than recreating the design in Adobe Illustrator. Because there is no anti-aliasing in Bitmap colour mode, the picture keeps a translucent backdrop.
So, what exactly is a Bitmap? Experiment with Bitmap Images
This exercise serves two functions. One is to show how to improve ‘organic’ writing, such as a signature, by experimenting with Median and Levels in Photoshop. The second goal is to show how we may add colour to it in a layout application like Photoshop or InDesign.
To begin, locate the signature.jpg file, which may be accessed by clicking here: So, what exactly is a Bitmap?
Launch Photoshop and open the file. When you double-click the magnifying glass, the view changes to ‘Actual Pixels’ (the smoothest view available). The signature appears OK on screen, but it won’t work in print. If you paste this into Photoshop or InDesign as is, it will have a white backdrop block and seem blurry.
The dimensions are 4.78cm x 5.08cm, and the resolution is 300DPI. We’d want to expand it to 10sm wide at 1200DPI and then convert it to line art (as a Bitmap image). To begin, increase the size by entering ’10’ in WIDTH and 1200 in RESOLUTION.
Navigate Layers
It needs to be cleaned up. Navigate to the LAYERS palette (shown below). Select LEVELS from the ADJUSTMENT LAYERS submenu (highlighted in yellow). We utilise adjustment layers rather than the LEVELS option from Picture/ADJUSTMENTS/LEVELS because we want our modifications to be non-destructive, which means that if we make a mistake, the original image will not be altered. In general, this is recommended practise for any picture retouching operations. Always preserve a layered PSD original in addition to your ‘flattened’ completed picture.
So, from the adjustment layers submenu, choose LEVELS. The white triangle slider should be moved to the left, and the black triangle slider should be moved to the right. As you do so (if PREVIEW is enabled), the image’s edges will become more defined.
However, the edges are still pretty ‘jittery’ at this point. First, we must apply a filter. Remove the adjustment layer.
Filters
Because the filters are ‘destructive,’ we will duplicate the background layer and apply the effect to the copy so that the original picture is not destroyed. To create a copy, drag the background picture over the ‘New Layer’ icon at the bottom of the palette. (See below.) Navigate to FILTERS/NOISE/MEDIAN. Adjust the radius slider to a value of roughly 10 pixels.
Reopen the LEVELS adjustment layer and combine the white and black sliders as shown below. As you can see, the edge is becoming sharper and smoother. We must now remove the anti-aliasing. You could convert the picture to Bitmap at this point, but there is more adjustment layer to apply to make the end output as excellent as possible. Select THRESHOLD from the Adjustment Layer submenu. If you leave it at its default setting, all anti-aliasing will be removed. This is the location where you store your PSD layered file. The picture should then be flattened (LAYER/FLATTEN IMAGE).
Image Mode
Choose IMAGE/MODE/BITMAP. The resolutions of the input and output should be the same (1200DPI). Click the OK button. Save the file in TIFF format. Now that we’ve completed Photoshop, let’s see what we can do with it in Photoshop or InDesign.
First, Photoshop. In Adobe Photoshop(version 6), go to FILE/NEW/PROJECT and create a new A4 document. The default setting should be A4 LETTER. Uncheck the FACING PAGES and AUTOMATIC TEXT BOX boxes. Produce two new hues. We’ll be working in CMYK rather than Spot colour, so choose EDIT/colours. Select NEW. ‘Dark Blue’ is the name of the colour. Fill in the CMYK fields with the following values: C 100% M 50% Y 0% K 50% Click OK.
Make another new colour (‘Light Green’). Use the following values: C 25%, M 0%, Y 50%, and K 0%.
REMEMBER TO LOOK AT THE COLOUR WHEEL. When it comes to complimentary colours (hues that go well together), colours opposite each other on the colour wheel tend to go well together.
Fill a huge rectangle on the page with the Dark Blue using the PICTURE BOX icon in the toolbar. From the toolbar, choose the CONTENT tool. FILE/GET PICTURE and go to the location where you stored your Bitmap picture. Put it there. In the blue box, it will seem black (with no backdrop).
Show the colour palette and choose the centre PICTURE colour icon at the top while keeping the rectangle and content tools selected. The signature will change colour once you click Light Green (see below). The preview quality in Photoshop does not do the final product credit; print it out to see how gorgeous and sharp it is.
InDesign is quite similar
FILE/NEW/DOCUMENT, PAGE SIZE A4, FACING PAGES, and MASTER TEXT FRAME are all deselected. Click the OK button.
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