Perbedaan RGB dan CMYK - Menghindari kesalahan pada proses cetak

Permasalahan yang sering timbul dalam dunia desain grafis adalah ketika desain dihadapkan dengan dunia produksi. Banyak sekali desainer grafis yang handal ilmu desainnya, mahir penguasaan toolnya, namun lemah terhadap pengetahuan dalam bidang produksi. Hal ini menyebabkan hasil akhir produksi dari suatu desain biasanya kurang memuaskan. Masalahnya bisa beragam, namun seringkali ditemukan pada perbedaan hasil dari warna pada proses cetak.

Permasalahan ini sederhana dan lazim terjadi di dunia percetakan. Diakibatkan dari kurangnya pengetahuan desainer terhadap konsep dasar dan teori warna. Warna dalam dunia percetakan berbeda dengan warna tampilan di monitor. Teori ini dibagi berdasarkan dua model warna : RGB dan CMYK. Perbedaan inilah yang kemudian menyebabkan seringnya terjadi kesalahan atau hasil yang tidak diinginkan dari warna akhir melalui proses cetak.

Adapun perbedaan warna RGB dan CMYK, secara sederhana dapat dijelaskan seperti ini :

Warna RGB adalah model warna additive yang bertujuan sebagai penginderaan dan presentasi gambar dalam tampilan visual pada peralatan elektronik seperti komputer, televisi dan fotografi. Warna RGB difungsikan untuk tampilan di monitor komputer karena warna latar belakang komputer adalah hitam. Jadi, R = Red (merah) G= Green (hijau) dan B = Blue (biru) sebagai warna dasar difungsikan untuk berbagi intensitas cahaya untuk mencerahkan warna latar belakang yang gelap (hitam).

Sedangkan CMYK adalah warna yang dikenal dalam proses printing dan percetakan. Terdiri dari C = Cyan, M = Magenta, Y = Yellow, dan K = Black. Warna CMYK digunakan untuk tampil seimbang dengan latar belakang putih dari bahan cetak seperti kertas dan lain-lain.



Warna RGB biasanya lebih terang dan jelas, biasanya menghasilkan besar kapasitas file yang lebih kecil. Warna RGB sangat cocok untuk presentasi visual dalam tampilan monitor seperti desain halaman web/situs. Ketika suatu karya desain dalam format RGB akan diprint dan melalui suatu proses cetak, maka warna RGB harus dikonversi dahulu kedalam model warna CMYK. Hal ini karena printer dan mesin percetakan hanya mengenal warna CMYK sebagai model warna dari kalibrasi di mesin cetak.

Sering kali beberapa karya desain yang akan naik cetak masih dalam format RGB, dan ketika dikonversi menjadi CMYK, warna biasanya akan berubah menjadi lebih redup dan tidak secerah warna yang tampil pada model RGB. Solusi dari masalah ini adalah, desainer harus memastikan dulu desainnya tampil dengan warna yang diinginkan dalam format warna CMYK, karena yang akan keluar dari mesin cetak adalah warna dengan model CMYK.

Beberapa software/aplikasi untuk desain grafis biasanya mengizinkan kita untuk bekerja dengan memilih antara dua model warna (RGB atau CMYK) walaupun dalam beberapa hal, seperti beberapa fungsi dari photoshop tidak akan aktif jika kita bekerja dalam model warna CMYK. Pemilihan model warna biasanya akan tampil ketika kita membuka dokumen baru. Namun, apabila sudah terlanjur bekerja di salah satu model warna dan kita ingin menggantinya, kita bisa menkonversi kembali model warna tersebut.

Berikut beberapa cara konversi model warna dari RGB ke CMYK di beberapa software desain grafis :

Adobe Photoshop
Pada menu bar pilih: Image > Mode > CMYK

Adobe Illustrator
Pada menu bar pilih: File > Document color mode > CMYK color

CorelDRAW
Pilih masing-masing objek yang akan dikonversi. Pilih Fill tool dan klik Fill Color Dialog. Pastikan model warna adalah CMYK. Untuk setiap objek dengan garis/outline : Pilih Outline tool dan klik Outline Color Dialog. Pastikan model warna adalah CMYK.

Microsoft Publisher 2003-2007
Pilih Tools > Commercial Printing Tools > Color Printing, pilih Process Colors (CMYK)

Adobe Indesign
Pilih Window > Swatches dan Window > Color. klik ganda color di Swatches dan ganti color mode ke CMYK dan color type ke Process.




http://www.desainstudio.com/2010/06/perbedaan-rgb-dan-cmyk-menghindari.html

cara bikin effek kayak gini make photoshop

 

Introduction

The idea was used on CynaraSource.com and I thought it’d make a nice tutorial… don’t even ask why I was visiting a site dedicated to artichokes

Step 1

Begin by opening a new document, mine is 540×300 at 72ppi as usual.
In the Tools bar set your foreground and background colors to #67774b and #303824 respectively then choose the Rectangular Marquee tool my pressing the M key. Drag a selection around the top 2/3 of the document as shown below.

Step 2

With the selection made, switch to the Gradient tool and make sure that the Foreground to Background setting is selected from the top-bar and that Linear Gradient is also selected.

Step 3

Click and drag from the bottom of your selection to the top to lay down a Linear Gradient.

Step 4

Invert the selection now by choosing Select>Inverse from the main menu or simply press Command-I (PC: Ctrl-I) to invert the selection using your keyboard. Once the selection is reversed and with the Gradient tool still selected, drag a line from the top of this selection to the bottom like the example below.

Step 5

Deselect by pressing Command-D (PC: Ctrl-D).
Create a new layer by clicking the new layer icon at the bottom of the Layers palette or by choosing Layer>New>Layer… from the main menu. Double click on the layers name in the Layers palette and call this layer "Water Drop".

Step 6

In the Tools bar change the foreground color to a green which is lighter than the lightest green we used for the gradient, I used #7f8a69.
Switch to the Elliptical Marquee tool (which can be found in the fly out menu activated by clicking and holding your mouse on the Rectangular Marquee tool in the top left corner of the Tools palette), then drag out a nice drop-shaped oval on the stage like the one below. We are going to build the drop rather large, then scale it down to get the desired effect later.
With your selection made, press Option-Delete (PC: Alt-Backspace) to fill the new selection with the light foreground green we just selected then deselect by pressing Command-D (PC: Ctrl-D).

Step 7

Bring up the Layer Styles dialog box by double clicking on the layer thumbnail in the Layers palette and apply the following 3styles then click OK.

Step 8

Your drop should look like this.

Step 9

Create a new layer just like you did in step 5 and name it Drop Highlight. Switch to the Brush tool by pressing the B key and choose a round brush with soft edges about 45 pixels in diameter with a hardness of 0%.

Step 10

Press the D key to reset the foreground colors to Black and White, then press the X key to switch the foreground and background colors, thus making the foreground color white.
Place the brush where the highlight for the droplet should go and click once.

Step 11

Now lets transform the highlight to ovalize and tilt it for a little more realism. Press Command-T (PC: Ctrl-T) to activate the Free Transform tool and using the anchor points stretch and rotate the highlight until it looks satisfactory. Press Return (PC: Enter) to commit the transformation.

Step 12

Follow the next few steps very carefully:
1) With the "Drop Highlight" layer still selected in the Layers palette, hold down the Shift key and click on the Water Drop layer (this will make it so both layers are selected at the same time).
2) Ctrl-Click (PC: Right-Click) on either layer and choose Duplicate Layers. A box will come up asking you to name the layers, just click ok. This will create two identical layers above the two layers we just had selected and the two new layers will now be highlighted.
3) Press Command-E (PC: Ctrl-E) to merge the two selected layers together then rename the layer "Reflection" and lower it’s Fill opacity to 40%.

Step 13

Now lets move the "Reflection" layer below our other two layers by pressing Command-[ (PC: Ctrl-[) or by simply grabbing the layer and dragging it below the other two layers.
Switch to the Move tool by pressing the V key and click and drag the reflection down until it looks like the one below.

Step 14

At this point our drop and reflection are complete and ready for sizing and placement. With the "Reflection" layer selected, hold down the Shift key and click on the "Drop Highlight" layer to select all three layers the comprise our droplet then press Command-E (PC: Ctrl-E) to merge the three layers together. You may want to rename the merged layer Drop or something so you know what’s on it.
Press Command-J (PC: Ctrl-J) to Duplicate the layer, then turn off the first copy and keep it hidden as your full-size drop. This will be useful if you want to duplicate and transform more drops so that you’re not loosing information during transformation each time.
With the new layer selected press Command-T (PC: Ctrl-T) to invoke the Free Transform tool just like we did before, now just drag the corners until the drop is a sufficient size. (*note: holding the Shift key will constrain the transformation) – Repeat this duplication and transformation process as desired.

Step 15

In my final example I thought I’d add the iPod Shuffle we created in an earlier lesson in a red color with it’s own reflection to add a little more depth to the project.

Lesson Files + Additional Resources

Download the free .PSD file and other lesson files Right Here.

tutorial photoshop :Old School Type – Line Gradients

One of our readers suggested we write a tutorial explaining how to do this cool text effect. On the Dragonforce logo above, the basis of my typography was sketched on paper first and then vectored in Illustrator using the Pen Tool. The process for creating the base logo is not included in this tutorial. Instead, we are going to take the base logo and add that cool “line gradient” effect that you see inside the actual letters. This gives the text an old-school or vintage feel to it. This look is prevalent in wood engraving and sign lettering. You can do this effect with any typeface or font because the principle is the same.
Here are some more examples:



So in order to get this effect, we will need both Adobe Illustrator CS2 or higher and Adobe Photoshop.
You can see the kind of effect we are going to create. This is going to cover the basic technique. But I encourage you to be creative and experiment with different things. That’s how you learn! Begin the tutorial after the fold.

Step 1: Prepare your base logo or typeface.

We will use our Dragonforce Logo as our base, but you can simply use your favorite font. Just make sure it’s thick and bold to make room for the line effect.
1a: Open up Adobe Illustrator and Photoshop
1b: Create your base text (just type something out using a bold font)

Step 2: Make a new document in Photoshop

You’ll need to make a new document in Photoshop that’s 2500×2500 pixels and 300 DPI. This will be where we will create the line gradient. But first, we need to get your text into Photoshop.

Step 3: Back in Illustrator, select your inner most shape in your text and copy it.

If you’re just using a font, simply click on it to select it. Press Ctrl+C or Edit>Copy to copy the shape to your clipboard.

Step 4: Paste it into your new Photoshop document.

Switch back into your Photoshop document and press Ctrl+V or Edit>Paste to paste your text layer. It will ask if you want to paste it as a Vector Smart Object or as Pixels. Choose pixels.

Step 5: Make the text black.

If your text is already black, skip this step. You can either use brightness & contrast, levels, or whatever you want to make your text black. I did it by Ctrl+Clicking on the layer’s thumbnail image to make a selection around my shape. Then I pressed “D” to reset my colors to black and white and then Alt+Backspace to fill my selection with Black.

Step 6: Give your layer a white “inside” stroke.

Go into your layer properties and give your black text a white stroke. Align the stroke to the “inside” so that it looks like it eats away your text. You’ll see why we are doing this later.

Step 7: Isolate JUST the black layer by using Select > Color Range

From your menu up top, find “Select > Color Rage” and press OK. This should have already selected all the Black pixels by default. If not, you can choose “shadows” from the drop down menu. Once you have the selection made, make a new layer and press Alt+Backspace to fill the layer with black. You can then delete your previous layer with the white stroke. What we just did in the last few steps was make our text “thinner” so our line gradient has some spacing away from the edges of the text.

Step 8: Create your gradient and convert to Bitmap

8a: Ctrl+Click your new layer with just the black “thinned” text to make a selection around your text.
8b: Use your gradient tool to create a black and white gradient from bottom to top of your text.
8c: Select Image>mode>Grayscale – if it’s not there already
8d: Once it’s in Grayscale mode, select Image>Mode>Bitmap and then you’ll get a series of dialog boxes.
8e: Select “Halftone” screen from the dialog box. Make sure your resolution says 300 DPI.

8f: Select a frequency of about 6, angle of 0 degrees, and Shape of “line” – these settings determine how our bitmap will look. Feel free to tweak these to get whatever effect you want.

This what we have created after converting the gradient to a bitmap:

Step 9: Take your image into Illustrator to live trace it!

The easiest way to get your image in Illustrator to Live Trace it is to drag and drop it. So select your Move tool in Photoshop and physically drag your artwork onto the Illustrator button on your taskbar. With your mouse button still held down, hover over the Illustrator button on your taskbar until the Illustrator window pops up. Now you’ll notice that your icon will change when your holding it over the artboard in Illustrator. Let go of the mouse button and your image will be placed into Illustrator. It will most likely be really big and you’ll need to zoom out a bit to see it.
So with it still selected, click the Live Trace button up top, or go to Object>Live Trace. Then click the expand button after that.
9b: Once you have it Live Traced and expanded, right click and ungroup your newly live traced shape. This will separate all the black shapes from the white shapes.
9c: Click on white area around your text (you may not see it, but it’s there) to select a white shape. Then go to select>same>fill color to select all your white shapes. Press Delete to get rid of them. You only need the black shapes.
9d: So now that you’re left with just the black shapes, select all of them by dragging a large selection box around it. Once they’re all selected press Ctrl+G to group them.

Step 10: Scale down your new vectored line gradient and fit it onto your base text

I scaled it down and tweaked the size so it fit perfectly within my original base text. I changed the color to match it. I ended up with my final image below. That’s it!

Conclusion:

In this tutorial you learned how to use Photoshop and Illustrator to create cool looking “Vector Line Gradients” to give your text a vintage “old-school” feel. This can be applied in lots of different ways including background gradients or halftones. In fact, in Go Media’s Vector Halftone pack in Set 3, you can choose from a variety of premade line gradients which you can use with just a little bit of work.
I encourage you users who follow this tutorial to post your designs in our user showcase to show off what you’ve learned.
Oh one cool tip to get some rad halftones is the Andromeda Screens filter. Check it out and play with it. Some of those designs you see below with the curvy line gradients were created with it. It takes some getting used to, but it’s cool.

---

tutorial photoshop :Simple, Sleek & Stylish Text Effect

In this short and simple tutorial I’m going to teach you how to make a very stylish, sleek text effect, like the example I’ve shown in the below image.

1. Background

Let’s start by creating a new document in Photoshop. After creating a new document around 500 x 500 pixels in size, add in a nice radial gradient background. Colors I used for my gradient background were: #717577 and #191918.

Now, you can either continue on and make your text, or you can finish off the background by adding in another effect. I added another interesting effect to the background by adding a texture to the background, then applying Filter > Pixelate > Mosaic to the texture.

After applying Mosaic to the texture, change the layer mode to Overlay and lower the opacity to around 10-25%. You should be left with something like this:

Moving on to the adding text part!

2. Adding Text

Now it’s time to add some text to your canvas. First, find and get out the Horizontal Type Tool, then drag a selection inside of your canvas. Connect the two sides of your text selection to the sides of your canvas, so the text can be perfectly centered. Write out your text.

In the above image, I’ve used a font called News Gothic Std, which sadly is not a free font. Feel free to try different fonts though, a good alternative is Arial, which comes with Windows.
For all of my other font/text settings, see the below screenshot:

Got that down? Excellent!
Next we’ll add some effects/styles to the text to make it look more interested.

3. Add Layer Styles / Effects

Right-click your text layer in the layer’s palette and go into the Blending Options, here we can add some interesting effects to your text. Start by ticking Drop Shadow, Bevel and Emboss, and Gradient Overlay. How’s it look now? Not so brilliant I bet. Well, go into the below links to see what settings you have to change:

1. Drop Shadow
2. Bevel and Emboss
3. Gradient Overlay

And now your text should look like this:

Not too bad, huh? At this stage we’re pretty much finished, but I took it a tiny bit further and added a few extra things.

4. Add Gloss & Finishing Touches

Let’s finish up. Start by duplicating your text layer (right-click in layer’s palette, click Duplicate Layer…), and after duplicating rotate it slightly in Transform Mode. (CTRL+T)
After rotating and resizing your duplicate text slightly, create a new layer and merge the two together (duplicate layer and blank layer), after doing this, apply a slight Gaussian Blur filter (1.5).
You should have something like this:

After doing all of this, change the layer mode for your blurred text layer to Overlay and lower the opacity level to around 10-30%.

It may look a little lame, but meh. It’s just a random effect!
Lastly, I added a kind of glossy-shine to the text layer. You can do this by first selecting the text’s pixels (hold CTRL and click the layer’s thumbnail in the layer’s palette) then on a new layer dragging a white to black radial gradient, like the one shown below:

If you haven’t already, de-select your text pixels (CTRL+D) then find and get out the Pen Tool. Using the Pen Tool, create a curved path along your gradient, like how I’ve done in the below screenshot:

I hope I’ve been explaining this sufficiently so far! After making your path using the Pen Tool, turn the path into a selection by right-clicking the path and then clicking Make Selection, now press your delete key to remove the selected part of the gradient layer.

Hey, that just looks plain weird, doesn’t it? Change the layer mode for this gradient layer to Screen, and whammo, we’re done! How easy was that?

Much better. Well, it looks like we’re done for this tutorial. Are you happy with the result? If not, then keep experimenting with different things!