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Canon has a series of products under the “Glossy Photo Paper” name, with the forumla identification number of GP 401. They used to make many different types of paper under this forumla, but now it seems they only make the credit card sized paper.

The paper is flawed in that it has a slightly reddish tinge, which makes pictures a tad warmer than they should be. Compared against Canon’s PR 101 Photo Paper Pro (which is an almost neutral white, very slightly on the warm side), GP 401 can be described as pink.

This pink color shifts flesh tones and anything that uses magenta ink to print out to be shifted over to the pink side as well. Unfortunatley, the only way to get Canon branded credit card sized paper is to use this paper.

So, I just spent the last two hours slowly tweaking an existing ICC profile for a similar paper (Canon’s Photo Paper Plus, which isn’t nearly as red) to work correctly with this paper.

To get you close to the correct colors, set your “Media Type” to “Glossy Photo Paper”, and use the manual color adjustment dialog (click “Color Adjustment: Manual”, and click on “Set…”) to increase cyan to 35, magenta to 10, yellow to 25, and decrease intensity to -10. These alone increase the quality of output on GP 401 a lot, and make it similar to Photo Paper Pro.

Also, if you’re using Photoshop, or any similar professional printing application, disable ICM and use “Print Type” set to “None”. In Photoshop, you typically use Photoshop’s built in color management.

To use said color management, use “Print With Preview”, and select “Color Handling: Let Photoshop Determine Colors”, “Printer Profile: Canon i9900 SP1″, “Rendering Intent: Preceptual”, and turn “Black Point Compensation” on.

Now, this isn’t as good as just having an ICC profile for the GP 401, but it is about the best you’re going to get, it seems.

Inspired by a comment from someone reading my review of the Canon Rebel XT, I realized that a lot of people just don’t know how to fully use the potential of their camera and Photoshop. In a four easy steps, you can improve the apparent quality of your shots without even needing to resort to Photoshop (yet):

1. Use ISO 1600 to reduce motion blurring.
2. Use the AdobeRGB colorspace to reduce munging of colors not in the sRGB colorspace.
3. Capture in Raw, do not use JPEG as it only increases noise.
4. Increase the auto-exposure feature’s f-stop by 1/3rd or 1/2 to increase brightness of pictures. It is better to have over-bright pictures than under-bright, as brightening under-bright pictures increases noise, but darkening over-bright pictures only reduces noise.

These steps alone increase apparent picture quality boatloads. No more will you have noisy, dark, blurry pictures that look like they were taken with a bad webcam! Now, here is where Photoshop comes in:

Step 1: Since you are using Raw pictures now, you have to use a special plugin to load these images, which can be downloaded off Adobe’s website. This plugin allows you to load Raw pictures from tons of cameras. To get the best performance out of this plugin, under the Detail tab, set Sharpness to 0, and Color Noise Reduction to 0 (We’ll do color noise reduction next). Also, under the Curve tab, select a Linear tone curve.

Step 2: Pictures taken with a CMOS sensor (such as the Rebel XT’s) are often described as “butter smooth”, in as such as there is no obvious pixelation that CCDs cause. They are also low noise, and any noise that does show up (as such with high ISO speeds) looks a lot like film grain, and appears as color noise.

To clean up the little bit of noise that creeps in, use the Reduce noise plugin, using the settings shown to the right. Be careful, however, setting it too high, and you risk removing color detail, and setting it below 5 doesn’t do anything that can be noticed without zooming in 500%+.

Step 3: Now, many shots you take are probably very sharp. However, there is a neat trick that doesn’t involve real sharpening at all, but (ab)uses the Unsharp Mask tool instead. Using the settings shown to the right, you can easily increase the apparent sharpness without increasing the actual sharpness at all.

Increasing Amount allows you to increase the effect, but decreases the subtly, and this should be a subtle effect at all costs. Increasing the Radius changes the effect itself; above 25 and you start changing the overall contrast of the picture instead of specific areas, but below 15 it pushes small details more and it becomes very hard to notice any change at all.

Results

Now, here is a before and after showing what just using simple noise and sharpness management does using the three steps I outlined. Easily, you can tell the image is much clearer than before.

^{NR + UM 1:1}

^{Original 1:1}

^{NR + UM 1:3}

^{Original 1:3}

I’d like to thank the person who originally came up with the Unsharp Radius 20/20 trick. Unfortunately, I can not find where it came from, but whoever came across it originally found a real gem. Thanks you, whoever you are!