PhotoshopNews » Image Processing http://photoshopnews.com The latest news about the top pixel wrangling application on the planet. Sun, 17 Jul 2011 17:19:47 +0000 en-US hourly 1 http://wordpress.org/?v=3.5.1 Refine Edge hair masking in Photoshop CS5 http://photoshopnews.com/2010/04/30/refine-edge-hair-masking-in-photoshop-cs5/ http://photoshopnews.com/2010/04/30/refine-edge-hair-masking-in-photoshop-cs5/#comments Sat, 01 May 2010 04:56:59 +0000 Martin Evening http://photoshopnews.com/?p=3140 refineedge-sharp

Photoshop CS5 now offers the ability to successfully make cut-out masks of complex subjects against busy backgrounds. This isn’t something new as there are a number of third-party plug-ins that have been able to do this type of masking, but this is the first time Photoshop has provided an effective, built-in solution. OK, there was the Extract command (which no longer ships with Photoshop), but this method, using the new improved Refine Edge command works much better. Click here to view the movie.

Read more…

The main reason why the Refine Edge works as well as it does is down to the new ‘Truer Edge™’ algorithm that is employed in the Edge Detection section. As you can see in the movie, by using a basic quick selection to isolate the subject and using the Radius slider and Smart Radius in the Refine Mask dialog, these steps alone can get you pretty close to achieving a successful cut-out mask. The remaining tools allow you to fine-tune these initial results.

Adobe Photoshop CS5 for Photographers (Focal Press).
ISBN: 0780240522005
This extract was taken from Adobe Photoshop CS5 for Photographers (where you can access other sample movies about Photoshop CS5). This latest update in the Adobe Photoshop for Photographers series contains 768 pages in full color, plus a DVD containing video tutorials. The book layout has been further improved to make navigation easier and contains updated advice on everything you need to know about using Photoshop, from digital capture to print output, as well as all that is new in Adobe Photoshop CS5.

9780240521251

The title will be stocked in most major bookstores throughout the world and also available to purchase from:
www.focalpress.com as well as through the on-line bookstores: www.amazon.com and www.amazon.co.uk.

The Adobe Photoshop CS5 for Photographers book is expected to start shipping after mid-May 2010.

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One way to retouch loose hairs http://photoshopnews.com/2009/04/05/how-to-retouch-loose-hairs/ http://photoshopnews.com/2009/04/05/how-to-retouch-loose-hairs/#comments Sun, 05 Apr 2009 16:34:54 +0000 Martin Evening http://photoshopnews.com/?p=2998 remove-loosehair-poster
Click here to view movie

This movie extract is from  Adobe Photoshop CS4 for Photographers: The Ultimate Workshop.

Here is an interesting challenge that I was presented with recently. I shot the model shown above for an advertising job and was asked by the client to make sure that the skin tone and nails looked flawless. After they had seen the initial retouch work they also asked if I could clean up the hair outline. At first it looked like this would be impossible to achieve. After all, how on earth can one use the clone stamp or healing brush to tidy up the fine hair strands against a background which consisted of a busy wallpaper pattern? As it turned out, the solution to this problem was staring me in the face!

Please note this video is in Quicktime format. A player can be downloaded from apple.com.

This movie extract is a smaller version of the one found on the DVD disc that comes with  Adobe Photoshop CS4 for Photographers: The Ultimate Workshop (now on sale), jointly authored by Martin Evening and Jeff Schewe. The book is published by Focal Press and contains 400 pages of tutorials and tips on how to achieve the best results out of Camera Raw and Photoshop. You can also find out more about the book by visiting the Photoshop for Photographers website where you can preview more of the content that will be appearing in this book.

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Camera Raw and the shadow output levels http://photoshopnews.com/2008/01/14/camera-raw-and-the-shadow-output-levels/ http://photoshopnews.com/2008/01/14/camera-raw-and-the-shadow-output-levels/#comments Mon, 14 Jan 2008 16:58:42 +0000 Martin Evening http://photoshopnews.com/2008/01/14/camera-raw-and-the-shadow-output-levels/ convert-levels-compare-low.jpg

Some image editing habits become so ingrained that it is hard to unlearn them when newer ways come along and make the old favorite methods redundant. An example of this is the subject of setting the output Levels in Photoshop for the print output. For many years Photoshop users were taught to set the output levels for the shadows at a slightly higher value than 0,0,0, even though (as you will read here) it has not been necessary to do so for quite some years now. Then came along Camera Raw and Lightroom and some photographers have been agonizing over how to set the output levels for an image when there is no output levels control in Camera Raw or Lightroom. Hopefully the following article will help shed some light on how Photoshop is still able to manage the output levels for you and why the solution is really a lot simpler than you would think.

Conflicting advice
You will sometimes come across advice that the output levels for the black point in an RGB image should be set to something like 20, 20, 20 (for the Red, Green, Blue RGB values) The usual reason given for this is because anything darker than say, a 20, 20, 20 shadow value will reproduce in print as a solid black. Just to add to the confusion, some people may suggest different numbers for the output levels: someone may suggest using 10,10,10, while another advises you use 25,25,25. In all this you are probably left wondering how to set the Blacks in Camera Raw, since you can only use the Blacks slider to clip the Black input levels and are offered no means to set a black levels output value using of the above suggested output settings.

This is one of those areas where the advice given is more complex than it needs to be. It is well known that because of factors such as dot gain, it has always been necessary to make the blacks in a digital image slightly lighter than the blackest black (0,0,0,) before outputting it to print. As a result of this, in the early days of digital imaging, the only way to get a digital image to print correctly was to manually adjust the output levels so that the black clipping point matched the print device. Back then, if you set the levels to 0,0,0, RGB, the blacks would print too dark and lose detail in the shadows. The solution therefore was to set the Output levels point to a value higher than this (such as 20,20,20 RGB), so that the blacks in the image matched the blackest black for the print device. These are the background reasons for such advice, because the black levels had to be adjusted differently for each type of print output including CMYK prepress files.

For the last 10 years or so, Photoshop has had a built-in automated colour management system that is designed to take care of the black clipping at the print stage. The advice these days is therefore really quite simple: you decide where you want the blackest blacks to be in the picture and clip them to 0,0,0, RGB (as discussed on the previous page). When you save the image out to Photoshop as a pixel image and send the image data to the printer, the Photoshop or print driver software will automatically calculate the precise amount of black clipping adjustment that is required for each and every print/paper combination. In the Figure 3.xx example you can see how the black clipping points for different print papers are automatically compensated when converting the data from the edited image to the profile space for the printing paper. But don’t just take my word, it is easy to prove this for yourself. Open an image, set the Channel display in the Histogram panel to Luminosity and refresh the histogram to show the most up-to-date histogram view. Then go to the Edit menu, choose Convert to Profile, select a CMYK or RGB print space and compare the before and after histograms.

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Figure 1. Here is the image that was used to generate the histogram panel views shown in the Figures below.

convert-prophotorgb.jpg

Figure 2. This Histogram panel view shows the original histogram for this ProPhoto RGB image. Note that this histogram and the others shown here all used the Luminosity mode since this channel view mode accurately portrays the composite luminance levels in each version of the image.

convert-levels-compare-flat.jpg

Figure 3. This histogram shows a comparison of the image histogram after converting the ProPhoto RGB data to a print profile space for Innova Fibraprint glossy paper printed to an Epson 4800 printer. The print output histogram is overlaid here in green and you can see that the black levels clipping point has been automatically indented.

convert-somerset-velvet.jpg
Figure 4. This example shows the print profile for a Somerset Velvet matte paper printed to an Epson 9600 printer, again colored green so that you can compare it more easily with the before Histogram. The black clipping point is moved inwards even more here because the matte paper needs a higher black clipping point to avoid clogging up the shadow detail. The same thing also happens when you make a CMYK conversion, but the black point will possibly shift inwards even more.

So is it wrong to set levels manually?
Not really. All l I am suggesting here is that it is an unnecessary extra step to use Photoshop to set the black output levels to anything higher than the zero black after you have already set the black clipping to the desired setting at the Camera Raw editing stage (or done so in Photoshop). If you do set the black output levels manually to a setting that is higher than zero you won’t necessarily get inferior print outputs, providing that is, you set the black levels accurately and don’t set them any higher than is needed. And there’s the rub: how do you know how much to set the output levels, and what if you want to output a photo to more than one type of print paper? You see, it’s easier to let Photoshop work this out for you.

Some picture libraries are quite specific about how you set the output levels, but their suggested settings are usually very conservative and unlikely to result in weak shadows when printed to most devices. It is therefore probably better to oblige the libraries with what they ask for rather than fight them over the logic of their arguments.

The only time when you may need to give special consideration to setting the shadows to anything other than zero, is when you are required to edit an already converted CMYK or grayscale file that is destined to go to a printing press, where the black output levels have been incorrectly set. But as I say, if you use Photoshop color management properly you won’t likely encounter such problems.

Conclusion
In conclusion I would say that you shouldn’t need to worry about what the output levels should be. If you are editing a photo in Camera Raw or Lightroom, all you need to concern yourself with is applying the black point clipping that you feel is most appropriate for each individual image. Then let Photoshop or Lightroom take care of the black point output levels conversion at the point where you send the image data to the printer.

About Martin Evening
Martin Evening is the author of Adobe Photoshop CS3 for Photographers as well as the Adobe Photoshop Lightroom Book. Martin is a London based fashion and beauty photographer as well as an alpha 7 beta tester for Adobe. He is also a founding member of Pixel Genius and was the product manager for PhotoKit Color 2.

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How to express blend modes as curves http://photoshopnews.com/2007/09/05/how-to-express-blend-modes-as-curves/ http://photoshopnews.com/2007/09/05/how-to-express-blend-modes-as-curves/#comments Wed, 05 Sep 2007 20:45:20 +0000 Martin Evening http://photoshopnews.com/2007/09/05/how-to-express-blend-modes-as-curves/ multiblendmodes.jpg

This tutorial is all about the relationship between Photoshop Curves and how all non-dissolve, per-channel Photoshop blend modes are equivalent to some kind of curve.
It has often been said that there is always more than one way to achieve an identical result in Photoshop. The trick of course is to work out which method is best for you or which is the most efficient.

As far as some people are concerned, Photoshop holds a certain mystique where it is assumed that a more complex approach will produce a more refined result. But very often the underlying math is the same as that used when applying a simpler approach. This is not to say that all tone adjustment methods can be reduced to a single curve, but the steps shown here are designed to illustrate the following three points:

1. It is always more efficient to use adjustment layer blend modes to ‘Screen’ or ‘Multiply’ an image rather than to duplicate the Background layer

2. An arbitrary map curve setting can be converted to a Photoshop Raw file format and edited in Photoshop.

3. By using this method to edit Curve settings, some cumulative image adjustments can be distilled into a single curve setting.

Adjustment layer blend modes

ca2006-0130-normal.jpg
Figure 1.

Figure 1 shows an unedited image where the sky requires darkening. The method we are going to use here is to use a Multiply blend mode to darken the overall image and then apply a black to white linear gradient to mask the bottom half of the picture. And in order to further darken the sky, we are going to duplicate the blend mode layer to produce a more pronounced darkening.

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Figure 2.

There are two ways you can do this. The most often taught method is to simply duplicate the Background layer and change the layer blend mode to Multiply. This will work, but when you save the image you will end up with a file which in this case will be three times the original file size!

A better alternative is to add an adjustment layer (any will do) without actually altering the settings and change the blend mode. This will achieve the exact same result as duplicating the Background layer but will only marginally increase the file size. So all you need to do is add an adjustment layer, let’s say a Curves adjustment layer, and click OK when the dialog appears to close it without editing the curve in any way. Then simply change the layer blend mode as before. It’s that simple.

ca2006-0130-darker.jpg

Figure 3. Here is the end result when using either of the methods described above. The sky only is darkened because the linear gradient hides the adjustment to prevent it affecting the lower half of the picture.

If you refer back to Figure 2 you will notice how I duplicated the Multiply layer and adjusted the layer opacity of this second layer to 60%. By altering the layer opacity and duplicating layers, you can have full control over the intensity of the ‘Multiply’ effect.

Convert a curves setting to a Photoshop image file
OK, now for the complex part. This next section reveals a little-known trick, in which you can convert a curves setting to a Photoshop Raw format image file, edit the image in Photoshop and save it back as a Curve setting. At this point I should mention that it was Russell Williams at Adobe who first showed me this tip and who helped clarify some of the points made here about the similarity between blend modes and Photoshop curves settings. Just remember that the steps discussed in this next section all relate to what can be summarized as the ‘non-dissolve, per-channel blend modes’ and excludes those other blend mode formulas like Hue, Color and Saturation that don’t operate on the individual channels.

Now, I have described all the steps here in detail so that those of you who are inclined to experiment are able to follow the exact same steps that I used. I appreciate that not everyone will be interested in these details, so if you like you can skip to the end of this article and download some of the settings I created using this method and put them to use.

Steps to edit a curve setting

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Step 1. I needed to create a gradient image that could be edited in Photoshop. One way to do this would be to create a new grayscale image that is exactly 1 x 256 pixels in size and draw a horizontal linear gradient going from black to white. But the gradient steps must be precise, where each pixel represents a discrete pixel value going from 0–255. The most accurate way to achieve this is to open the Curves dialog and click on the pencil icon to switch the Curves dialog to ‘arbitrary map’ mode. It is important that no edits are made to the curve. Next, I went to the dialog fly-out menu and chose Save Preset…

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Step 2. I then saved this preset to a desired location and clicked ‘Save’ to create the Cruves arbitrary map (.amp) setting shown here.

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Step 3. I then wanted to convert the setting into a Photoshop Raw file. To do this I renamed the setting file, changing the file extension from ‘.amp’ to ‘.raw’.

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Step 4. Now we can open the renamed raw file in Photoshop. You can use Bridge or the system navigation dialog to locate the file and then click Open.

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Step 5. This next bit is quite critical. The Photoshop Raw Options dialog will appear next and here I entered the dimensions for the file we were about to open: 256 pixels for the width and 1 pixel for the height. In the Channels section it was important that I set the count to 1, which meant that we would be opening this file as a grayscale image. After I clicked OK, another dialog appeared telling me that the specified image is smaller than the source file. I clicked OK to open anyway.

3arawoptions.jpg

Step 6. At this stage the missing profile dialog may appear (depending on how you have the color management preferences configured) and it is important here to NOT color manage the file we are about to open.

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Step 7. At last! We have managed to open the saved curve setting as a Photoshop image.

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Step 8. Now for the part where we edit the image file in Photoshop. In this example I added an adjustment layer and changed the blend mode to Multiply @ 100% layer opacity and then flattened the image to permanently edit the pixels in the file I had just opened. This is the stage where you can experiment using other blend modes, a combination of blend modes, or any other tone editing techniques that will work when applied to a grayscale image.

8-savecurve.jpg

9-saveoptions.jpg
Step 9. I saved the edited file to the Photoshop Curves presets folder. This can be accessed by going to the Photoshop application folder and locating the Curves folder inside the Presets folder. You will note here that I saved the file using the same Photoshop Raw file format, but I changed the extension to .amp when saving (in the ‘Save As’ section the file is saved as ‘Multiply.amp’). When I clicked Save, the Photoshop Raw Options dialog appeared and I simply clicked OK.

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Step 10. Now it is time to put the edited curve setting to use. I opened a new image, added a Curves adjustment layer and chose Load Preset… from the Curves dialog fly-out menu.

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Step11. I located the recently saved Multiply.amp setting and clicked ‘Load’.

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Step 12. This will load the curve setting for the multiply curve and append the setting to the list of presets that can be accessed via the Curves dialog Preset menu. As you can see below in Figure 4, one can use the steps described so far to add more presets to this list.

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Figure 4. Here is a screen shot showing the Curves dialog where I had created and added curve settings for more Photoshop blend modes.

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Figure 5. Here is a repeat view of the Curves dialog that was shown at the beginning of this article in which I have overlaid the curves used to define the Screen, Multiply, Soft Light and Overlay blend mode curves.

Putting theories to the test
There was a time when my instincts led me to believe that the Photoshop blend modes, in particular Screen and Multiply, performed some kind of special magic that made them superior to normal curves. I used to assume (incorrectly) that they somehow added levels to an image rather than simply stretched the existing levels in a picture, which is what Levels or Curves adjustments do. So one of the things this exercise allowed me to do was to directly compare blend mode created curves with basic blend mode adjustments.

As I said earlier, you can use the above steps to create your own set of blend mode curves, or if you want to cut out all the hard work, just download the ZIP file which contains a set of blend mode curves for you to experiment with.

In one test I did I took an image and duplicated it. For one version I added an adjustment layer, set the blend mode to say, Multiply and flattened the image. I then took the other version of the image, applied a Multiply curve and again flattened it. The two images should look identical. But not only that, they will statistically be identical too. One way to prove this is to overlay one of the images on top of the other in registration and set the blend mode to Difference. If the blended image is solid black, then you know that they are exactly the same. Now there is one point I will concede here. If you carry this out on an image that is in 8-bit per channel mode, the results will be identical. If you carry this out with an image that is in 16-bit per channel mode, the results will look the same but there will be a very slight difference in the statistical analysis. I raised this observation with Russell Williams, who explained that a curve map setting will specify an exact 256 values for the curve mapping and when this is applied to an image with more than 256 levels (i.e. a 16-bit image) it will have to interpolate the values that fall between those 256 points. Note here that the ‘interpolation’ here refers to the interpolation of the curve mapping for the in between curve values and this is true for any curves map mode type adjustment that is applied to a 16-bit image.

The other theory I wanted to test was whether blend mode adjustments will preserve more levels. The answer to this is no. A blend mode adjustment does exactly the same thing as a Levels or Curves adjustment, it simply maps the levels to new positions. Where clipping occurs some levels will be lost, but no levels will ever get added.

Blend modes use formulas to calculate the tone mapping and this it is argued, produces a smoother curve mapping when editing 16-bit images compared to using curve maps. This does appear to be true. For example, if you create a gradient test image in 16-bit, posterize it and compare the two different methods for adjusting the tones and then analyze the two histograms, the levels appear to shift more smoothly when you use the blend mode method of adjustment. So is the blend mode method still better? Possibly, although the difference between the two methods at 16-bit is so slight that it is hard to say which one is actually ‘better’. I would be interested to know what others think on this subject. As Russell Williams explained, the difference can be so negligible that the key conclusion would be to select whichever method was the most easy to use. This leads me to the final section where as an added exercise, I wanted to look at the possibility of merging multiple curves adjustments into one.

Merging cumulative adjustments into a single curve
At the beginning of this article I showed how two Multiply adjustments could be used to darken the sky in a beach seascape photograph. Now the chief advantage of working with adjustment layers is that you can mask the adjustment layer effect and the settings will remain editable. But when you add one adjustment layer on top of the other and flatten the image the image is effectively adjusted as if you had applied each of the curves adjustments sequentially. The downside of this is that the levels will get adjusted in sequence, one adjustment as a time, which is not the most efficient way to edit the tone levels in an image if you wish to preserve as much image detail as possible.

So for this final exercise I opened the standard Photoshop Raw linear gradient image and applied the same sequence of blend mode adjustment layers as were used in Figure 2 and applied these to the image, as shown in Figure 6. You will note that the uppermost adjustment layer has been set to 60% opacity, to match the settings used in Figure 2. I then flattened the image and saved the flattened file as a custom curve setting, naming it: ‘Multiply_100-60.amp’

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Figure 6.

I then opened up the original beach scene photograph and applied this custom curve setting. Figure 7 shows the layers palette with the single Curves adjustment layer in place. Figure 8 shows the curve shape appearance of the custom curve. And finally, Figure 9, shows the end result, which is identical to the one at the beginning of this article that was created using a combination of two adjustment layers.

15newsetting-2.jpg
Figure 7.

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Figure 8.

ca2006-0130-darker.jpg

Figure 9.

Conclusions
This main point of the exercises and steps shown here has been to provide some insight into the way Photoshop calculates its blend mode tone adjustments and how at one level you can say these have the same effect on an image as applying a normal curve adjustment.

Of course from a practical point of view it is not always going to be feasible to jump through all the hoops described here in order to create a ‘merged curves’ adjustment. But if for example you had a favorite tone mapping adjustment that involved say adding a gradient map adjustment followed by a curves adjustment to add a kick to the shadows followed by a layer blend options tweak, you could consider using the steps described in the last example to create a single curve setting that would let you achieve the same result in much less time.

But apart from that I did also want to demonstrate that in theory as well in practice, it could be possible for Photoshop to have a ‘merge adjustments’ feature in which certain types of multi-layered tone adjustments could be calculated as a single Curves adjustment.

Download the curve settings

If the above techniques interest you then you can download the curve settings as a ZIP file that I created for this article. The unstuffed folder will contain a Screen, Multiply, Soft Light and Overlay curve setting as well as the original Photoshop Raw file gradient image.

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Image Stacks in Photoshop CS3 Extended http://photoshopnews.com/2007/03/27/image-stacks-in-photoshop-cs3-extended/ http://photoshopnews.com/2007/03/27/image-stacks-in-photoshop-cs3-extended/#comments Tue, 27 Mar 2007 11:28:42 +0000 Martin Evening http://photoshopnews.com/2007/03/27/image-stacks-in-photoshop-cs3-extended/ align-stacks-04.jpg

Of all the new features in Photoshop CS3, those that stand out for me most are the ones that have been built around the new Align Content feature, engineered by Jeff Chien.

For example, you can use Align Content in Perspective mode to align group portraits and it is now possible to create really accurate Photomerge composites automatically.

Now that Adobe has announced Photoshop CS3 Extended alongside the regular version of Photoshop CS3, we can let you know about what some of the extended features will allow you to do. Of these, the Image Stacks rendering is, in my view at least, one of the most interesting new features in Photoshop CS3, better than Live Filters.

The new Stacks feature was engineered by Chris Cox and was originally designed as a tool for analytical work, where you could place a series of images together in alignment and apply a Stacks rendering to the layers and use this to process them in such a way that Photoshop will highlight the differences found between the layers, or as is shown below, blend the layers according to where there is a high frequency of recurring pixel values to display only the most commonly occuring pixel values. But I have also managed to discover several key creative uses for Image Stacks.

For this first demo, I had a series of six pictures where there was always at least one person walking through a scene. Using image stacks, I was able to automatically remove them from the shot.

align-stacks-01a.jpg

Figure 1- Here is a sequence of photographs that were shot hand held over a time period of a minute or so. There were a lot of people walking in front of the fountain and I just made sure that I captured enough shots so that each portion of the picture had two or more frames where someone wasn’t in front of the camera.

align-stacks-02.jpg

Figure 2- I opened all of these photographs in Photoshop and went to the File ➯ Scripts menu to choose: Load Files into Stack. This opened the dialog shown here, where I chose Use: Open Files and checked the Attempt to Automaticallly Align Source Images and Create Smart Object after Loading Layers options.

align-stacks-03a.jpgalign-stacks-03b.jpg

Figure 3- Depending on how many pictures you have and how large they are, it may take a few minutes to process all the photographs. What you will end up with will be a new document with a Smart Object layer that contains all the previously open image documents as layers grouped within the smart object. If you double-click on the Smart Object layer you will see the full expanded list of layers contained in this Smart Object.

align-stacks-04.jpg

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Figure 4- And now for the clever part. If you have the Smart Object open, make sure you close it again. You will want to start with the Smart Object selected (see the Layers palette top left). Go to the Layer menu and choose Smart Objects ➯ Image Stack Mode ➯ Median. Again, the stacks rendering may take a little while to complete. In the result shown here, the Median rendering managed to blend the layers such that nearly all of the people in the merged picture disapppeared completely.

align-stacks-05.jpg

Figure 5- The image stack median rendering did a pretty good job of removing the people, but there were still a few ghost outlines left. Obviously some people were having too good a time in the sun to want to move around much. Plus there were a few bits of rubbish and artifacts around the edges of the picture where the frames had overlapped. I tidied up the final picture by adding a little bit of spotting on a new layer and added some masked curves adjustment layers to provide some dodging and burning to produce the final version shown here.

Tips for getting the best results
When you see this technique demonstrated it does at first look quite magical, but there is a logical explanation for how the process works. The technique relies mainly on the use of the auto-align command to align a chosen set of sample images together and place them within a grouped smart object. After doing a little bit of experimentation I have found that if you record at least five or six (or more) exposures, this should provide enough separate images for Photoshop to process in order to work out which pixels appear most frequently at any particular spot in the picture and use the most commonly occurring pixels only to produce the finished blend shown here.

Removing noise using multiple exposures
Here is a technique that makes use of the Stacks feature in Photoshop CS3 to merge a set of identical exposures and obtain a smoother-looking image.

lowlight-01.jpg

Figure 6
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Figure 7
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Figure 8- I started by going to the File menu and choosing Scripts ➯ Load Files into Stack and selected a set of five images to open that had all been shot at identical exposures of a subject with the camera fixed to the tripod. These were photographs that had been shot at a high ISO setting using a long exposure in low light conditions. I checked the Align Source images and Create Smart Object options and clicked OK.

lowlighttest-2a.jpg

Figure 9- The selected images opened as a single image document grouped together as a single smart object. If I were to double-click on the smart object icon, this would open the smart object in a separate document window and allow me access to all the individual layers, which wasn’t necessary in this case, but would be if you wanted to edit any of the individual layers.

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Figure 10
lowlighttest-3a.jpg

Figure 11- Back in the original Smart Object document, I went to the Layer menu and chose Image Stacks ➯ Image Stack Rendering ➯ Median. The processing may take a little while, depending on the size and number of layers, plus bit depth. Once completed, you will notice how the Smart Object layer has a ‘stacks’ icon indicating the smart object has been rendered using the stacks feature.
lowlight-03.jpg

Figure 12

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Figure 13- Here is a comparison showing a close-up view of a single exposure (Figure 12) and a rendered version (Figure 13) where five separate exposures were merged to produce a smoother, noise-free image. The Median rendering was used here because it analyzes the image content on all the layers and averages out the pixel values to use the most commonly occurring pixel values only, thereby elminating nearly all of the noisy pixels that occur on each of the layers.

Median versus Mean
If you are processing a series of still life captures, then a Mean stacks rendering can remove more noise than Median. For example, if you were processing astronomy pictures, you would want to use a Mean rendering.

The techniques shown here are fairly easy to accomplish. The Align Content feature is so good at recognizing areas of similarity and aligning images together as layers, that you can quite easily get away without having to use a tripod to shoot the pictures that you want to combine together. So anytime you are in a situation where you think it might be useful to remove people from a shot or you want to improve upon the image quailty capture potential of a lowlight scene, just shoot a quick sequence of shots with the camera hand held, keeping it as still as possible.

About Martin Evening

evening.jpgMartin, if you don’t know, is a London based advertising photographer and noted expert in both photography and digital imaging. As a successful photographer, Martin is well known in London for his fashion and beauty work. Check out Martin’s web site.

Martin also works with the Adobe Photoshop engineering team consulting on new feature development and alpha and beta testing. He worked alpha & beta for Photoshop CS3 and Adobe Photoshop Lightroom and was influential with the new Adobe Bridge 2.0 and Camera Raw 4.0.

In addition, Martin is also a principal of PixelGenius where he designed and was product manger for the recently released PhotoKit Color 2. PhotoKit Color 2 applies precise color corrections, automatic color balancing and creative coloring effects. PhotoKit Color offers a comprehensive set of coloring tools for Photoshop 7.0, CS, CS2 (and soon CS3) for both Macintosh and Windows.

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New Adobe Digital Photography Primers http://photoshopnews.com/2006/11/28/new-adobe-digital-photography-primers/ http://photoshopnews.com/2006/11/28/new-adobe-digital-photography-primers/#comments Tue, 28 Nov 2006 18:06:46 +0000 PSN Editorial Staff http://photoshopnews.com/2006/11/28/new-adobe-digital-photography-primers/ Adobe has posted new white papers and primers available as PDF downloads. The PDFs are available from the Digital Imaging Solutions for Pro Photographers page (scroll to the bottom) and from the More Papers and Primers page.

New papers include:

The Role of Working Spaces in Adobe Applications
by Andrew Rodney
Photographer Andrew Rodney shows you what RGB working spaces are, why you need them, and when you might select one working space over another. This article provides the basic information you’ll need if you are using Adobe® Photoshop®, Adobe Camera Raw, or any application that supports International Color Consortium (ICC) color management.
PDF Dowload Link (468k)
Figure 4: 3D example from article
Figure 5: 3D example from article

A Raw Workflow in the Real World: The March of the Yellow Penguins
by Jeff Schewe
Use Photoshop CS2 for raw image processing, and boost your productivity. Photographer Jeff Schewe shows you how he took his raw workflow to the test under extreme Arctic conditions.
PDF Download Link (11.2MB)

Preparing Images for Delivery
by Jeff Schewe
What should photographers do to ensure that their images reproduce well in print? Jeff Schewe outlines how you can take some precautions and learn the lingo to communicate with your print service provider to get the print results you want.
PDF Dowload Link (7.1MB)

These new papers join the previously available papers (all updated for Photoshop CS2):

Digital Image Integrity
by George Reis
Photographs have been altered or “faked” ever since the very beginning of chemical photography. Learn how Photoshop CS is providing forensics experts and law enforcement specialists better tools for evaluating the authenticity of a photograph.
PDF Download Link (1.2MB)

Calibrating the Digital Darkroom Environment
by Karl Lang
If you want to create the most accurate prints possible in your digital darkroom, you’ll want to learn how to calibrate your work environment. Karl Lang steps you through the basics of how and why you need to manage your work environment as carefully as you do your studio lighting.
PDF Download Link (722k)

Black and White Conversion Tutorial
by John Paul Caponigro
Are you looking for more detail in your digital B&W conversions? Or perhaps better contrast and tonal separation? Here’s an opportunity to learn how to get maximum flexibility out of your B&W conversions. Follow along step-by-step, as John Paul Caponigro shows you how the pros do it in this dynamic PDF tutorial.
PDF Download Link (2.5MB)

Black and White Conversion Action
This download is a Photoshop Action (.atn) that automates the sequence of steps outlined in the JP Caponigro tutorial above. It is not required to complete the tutorial. This Action is compatible with Adobe Photoshop CS and CS2. Action Download Link (10k)

About Metadata
by Jeff Schewe
Find out how to give your images more value — and make them easier to find — by learning the basics of metadata.
PDF Download Link (4MB)

A Color Managed Raw Workflow
by Jeff Schewe and Bruce Fraser
Messy chemicals and processing trays are a thing of the past, but you’re still the one who must be sure your raw photos are processed properly. Learn how to take control by mastering these basics of color management in your raw workflow.
PDF Download Link (5.3MB)

Making the Transition from Film to Digital
by Michael Reichmann
Making the transition from shooting film to shooting digital is an exciting journey, but without this roadmap you might find more detours than solutions. Author and photographer Michael Reichmann provides a guide to the new language of digital photography, and will help you identify the crucial differences of shooting with film.
PDF Download Link (1.5MB)

Highlight Recovery in Adobe Camera Raw
by Jeff Schewe
The best digital cameras have about the same dynamic range as transparency film, but with Adobe Camera Raw you can actually process your raw images to pull out more highlight detail than you may have thought possible.
PDF Download Link (3.3MB)

State of the Art
by R. Mac Holbert
When is a photograph deemed “art”? Today, the adoption of digital photography would seem to be pushing the clock back over 100 years, judging from the resistance of some to the new technologies. R. Mac Holbert gives us his perspective of the state of the art in this timely article.
PDF Download Link (435k)

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PixelGenius announces plug-in updates http://photoshopnews.com/2005/04/07/pixelgenius-announces-plug-in-updates/ http://photoshopnews.com/2005/04/07/pixelgenius-announces-plug-in-updates/#comments Thu, 07 Apr 2005 10:00:23 +0000 PSN Editorial Staff http://photoshopnews.com/?p=178 Press Release: Chicago, IL – April, 7th, 2005 – PixelGenius, the makers of the PhotoKit™ series of Adobe® Photoshop® productivity and workflow plug-ins, announces that by the time Photoshop CS2 ships, they will offer free updates to PhotoKit, PhotoKit Color and PhotoKit Sharpener.

Andrew Rodney, PixelGenius principal, says: “We’ve been testing our products in the new Photoshop CS2 environment. Most of our current plug-in versions will already run correctly in Photoshop CS2. There is a minor issue with our splash screen dialogs, but we’ve already addressed that issue with an upcoming update. We will be releasing the new updates to handle all known issues prior to Photoshop CS2’s ship date. The updates will be free to all registered users. Our PhotoKit-EL products for Photoshop Elements 2 & 3 are uneffected.”

About: PhotoKit
Analog Effects Toolkit
PhotoKit is a photographer’s plug-in toolkit comprising 141 effects that offer accurate digital replications of analog photographic effects. PhotoKit’s image enhancements and adjustments are designed to work in a way familiar to photographers. A simple dialog calls up the PhotoKit tool sets, where you can easily select the desired image effect, and let PhotoKit do the work and greatly improve your digital photography workflow.

About: PhotoKit Color
Creative Color Effects
PhotoKit Color provides a comprehensive suite of effects that let you recreate creative effects like black and white split toning and cross processing. All these effects are applied as separate layers so the user can make further variations, adapting each effect to suit their own tastes. But that’s not all! With PhotoKit Color, you can enhance specific colors in your photographs. You can make skin tones less red or lighter. With the Blue Enhance effect you can darken a blue sky and enhance the cloud contrast. And with the RSA Gray Balance set, you can automatically remove color-casts from almost any type of image.

About: PhotoKit Sharpener
Complete Sharpening Workflow
Other products may provide useful sharpening tools, but only PhotoKit Sharpener provides a complete image “Sharpening Workflow”. From capture to output, PhotoKit Sharpener intelligently produces the optimum sharpness on any image, from any source, reproduced on any output device. But PhotoKit Sharpener also provides the creative controls to address the requirements of individual images and the individual tastes of users.

About PixelGenius
Founded in 2001, Pixel Genius, LLC. is a collaboration of industry leading experts dedicated to creating leading edge products and services for the photographic and digital imaging industries. PixelGenius is headquartered in Chicago, Illinois. Company principals: Martin Evening, Bruce Fraser, Seth Resnick, Andrew Rodney, Jeff Schewe and Mike Skurski.

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PhotoKit Sharpener “Highly Reccomended” http://photoshopnews.com/2005/01/01/photokit-sharpener-highly-reccomended/ http://photoshopnews.com/2005/01/01/photokit-sharpener-highly-reccomended/#comments Sat, 01 Jan 2005 19:20:52 +0000 PSN Editorial Staff http://photoshopnews.com/?p=23 PixelGenius’s product PhotoKit Sharpener was rated “Highly Recommended” in the What Digital Camera Magazine 2004 awards for software in the January 2005 issue. Tied with IView Multimedia Pro, it was bested in the software catagory only by Photoshop CS which was named winner.

The magazine said: “A Photoshop plug-in that solves the perennial sharpening problem by doing it for you. A range of options allows you to choose the right sharpening effects for the type of image, and the final output. Indispensable.”

PixelGenius is a collaboration of industry leading experts:
Martin Evening, Bruce Fraser, Seth Resnick, Andrew Rodney, Jeff Schewe & Mike Skurski.

For more info, see the PixelGenius Web Site

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Categories http://photoshopnews.com/2004/09/01/categories/ http://photoshopnews.com/2004/09/01/categories/#comments Wed, 01 Sep 2004 16:35:05 +0000 PSN Editorial Staff http://photoshopnews.com/?p=145

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If, this were a real emergancy, you would be out of luck!

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You can quit reading now. . .

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