Combining images to increase depth of field and dynamic range.

At the last meeting and workshop the topic of increasing dynamic range by combining photos with photoshop and Photomatix was discussed. It was mentioned that a similar technique could be used to increase depth of field beyond what is physically possible with optics. Thanks to Bob Boner who provides the sources for more information on this topic.

Naturescape article on combining photos in Photoshop to increase depth of field.

HeliconFocus is software to increase depth of field through image combination. Basically, this automates what is otherwise a very tedious time consuming process in photoshop.

Photomatix is software to increase dynamic range by combining images. (as discussed by Tony Sweet at the January meeting)

 

photoshop users tv

Yes there is a weekly tv show for photoshop junkies… its on the web.

Photoshop User Tv 

 

Photoshop Elements plug in: Smart Curves

A lot of us don’t need or can’t bear to pay for the full version of photoshop. Most of the time Elements will suffice. But it sure would be nice to have curves. Turns out there is a free plugin that works pretty well.

SmartCurves by EasyFilter

 

Flasher in the Landscape

I spent a wonderful Saturday evening as a guest of Potomac Valley Nature Photographers (you were invited too) at Antietam Battlefield. If you have been following the blog you may have noticed I’ve been inspired to use my little strobe off camera.  That inspiration comes from the Strobist. Here is an example.

Gear: In addition to your camera you will need the ability to remotely trigger your flash. Nikon owners with a D70 or above using a SB600 or SB800 strobe have this capability built in. Sorry I don’t know the details for other manufactures. Perhaps someone can leave an enlightening comment. A tripod will be very helpful as you’ll be shooting in dim light.

Shooting: Let your imagination go wild. But this technique works best with some interesting foreground element that is relatively dimly lit and a relatively bright background…like the sky. For our example I chose a fence at sunset. In this scene the actual sunset is behind the camera and obscured by cloud. I used a graduated neutral density filter to darken the sky a bit but otherwise this is what the scene looked like without any processing etc. The vignetting is from my Cokin filter holder…I need to get the wide angle version…or as suggested to me just hold the thing.

Okay, agreed not too earth shattering. The above picture was not used to make the final image its just to show the “straight scene”.

Here is the fun part. Place your flash to light the foreground element. Try different placements. Go wild. Make people including fellow photographers think you’re a little nuts. Pretend to be a little kid. You get the idea. Whatever it takes.

I chose the following image to make my final picture.

A little more interesting but certainly not finished. If I actually knew what I was doing, I’d have turned down the flash a little and exposed the rest of the scene a little more. Add a warming gel to the flash and this might not have needed much post processing at all. But alas, I don’t know what I’m doing and we thankfully have Photoshop and Elements.

Post Processing: With flash (as exposed) this is a fairly high dynamic range picture so you should have shot it in RAW. If you didn’t go back and re-shoot. Do two raw conversions of the one image. One exposed for bright areas and one exposed for the dim areas. Convert both to JPEG. (In Elements the conversion to JPEG is a must I’m not sure about Photoshop.)

The bright version:

The dim version:

Now layer the two images, the the bright one over the dim one. In Elements use the eraser set at maybe 30 percent opacity to erase away areas that are too bright in the top layer. This step in photoshop involves masks…you’ll have to tell me how it works…or ask Cathy or Al. Merge or flatten the two images.

I then did a little cropping and used a skylight filter plus a little red to make it look as if the last sunbeam of the day was illuminating the fence.

Hope you like it. For my next project I’m going to hide about a dozen strobes in and around that tree in the background! For a larger version and a bit of historical info on this place click here.

 

Creating a Sketch

Here is a great original article by Cathy Gilleland 

Since our last Photoshop workshop session discussed converting color images to black and white, I thought that this month we’d look at a related topic, turning photos into sketches. Although there are several filters in Photoshop that will give you a basic sketched look, such as Graphic Pen or Chalk and Charcoal, other techniques will give you even more convincing results. As usual, I’ll describe several ways to accomplish the sketched effect, and my directions assume that you are starting with just one background layer. Commands are based on a PC. For Mac users, generally “Alt” will be “Option” and “Ctrl” will be “Command.” Always work on a duplicate layer or duplicate image to protect your original, and don’t be afraid to experiment with different settings and blend modes.
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For the first technique, open an image.
Duplicate the background layer.
Desaturate the duplicated layer (Image/Adjustments/Desaturate).
Duplicate this desaturated layer.
Invert (Ctrl/I or Image/Adjustments/Invert).
Convert the layer blend mode to Color Dodge. The image will become almost totally white.
Now watch the magic by going to Filter/Blur/Gaussian blur and adjusting the radius to your liking.
Add a Levels adjustment layer if you want more contrast.
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One of the easiest ways to get the appearance of a drawing is to use Threshold.
Open an image.
Go to Layer/New Adjustment Layer/ Threshold and move the slider until you like the effect.
This works best on images with simple, strong lines and not much detail.
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For a lighter touch, open an image.
Duplicate the background layer.
Go to Filter/Blur/Smart blur. Change the Mode at the bottom to “Edges only” and the Quality to “High.” If you set the Quality to “Low,” you’ll get more detail, which you might prefer.
There are no definite settings for the Radius and Threshold. You want enough white lines to show the subject matter, but not so many that it looks “busy” and complicated. With some trial and error, you’ll figure out what works for you. Click OK.
Now invert the layer using Image/Adjustments/Invert.
You now have a line drawing. If you lower the opacity of that layer, or change the blend mode, the color beneath will show through, yielding a different effect.
Use a Levels or Curves adjustment layer if you want to increase the contrast.
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Open an image.
Duplicate the background layer.
Desaturate the duplicate layer (Image/Adjustments/Desaturate).
Duplicate the desaturated layer.
Run Filter/Stylize/Find Edges.
Change the layer’s Blend Mode to Soft Light.
Now duplicate that layer again, leaving it in Soft Light mode. You should now have a soft sketched effect.
To bring back some color, lower the opacity of the first desaturated layer.
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For a little different effect, open an image, duplicate the background and desaturate that layer.
Increase the Contrast (use Image/Adjustments/Brightness-Contrast rather than an adjustment layer).
Now go to Filter/Stylize/Find edges.
Rather than just accepting the default result, go to Layer/New Adjustment Layer/Levels.
Use the middle slider for shading, the left for line thickness, and the right for brightness.
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 For a similar result, but with some color retained:
Duplicate the background layer and set the Blend Mode to Overlay at 60% opacity.
Run Filter/Stylize/Find edges.
Duplicate again, leaving the mode and opacity settings as they are, and run Find Edges again.
Repeat again if desired for added contrast.
For a softer look, add a Gaussian blur (Filter/Blur/Gaussian blur) to the middle layer.
For a more hand-tinted look, add a Hue/Saturation adjustment layer and decrease the saturation.
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Do some experimenting with filters and blend modes. Here is just one example.
Open an image. Duplicate the background layer.
Run Filter/Sketch/Chalk and charcoal.
Duplicate the original background layer again and bring it to the top of the layer stack.
Run Filter/Sketch/Photocopy and set the blend mode to Soft Light.
Duplicate that layer and see what you get. Try different blend modes and different sketch filters. You could end up with a masterpiece!
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[Knight]
For the look of a soft pencil sketch, open an image and go to Layer/New/Layer from Background. This just turns the background into a regular layer, so it’s OK to accept the default settings that appear.
Duplicate the background but turn off this duplicate (click on the eye) temporarily.
Return to the original background layer and use Filter/Noise/Add Noise. The settings will vary, but start with: Amount 14, Distribution Gaussian, and check the Monochrome box.
On that same layer, go to Filter/Brush strokes/Angled strokes and try these settings:  Direction Balance 100, Stroke Length 10-20, and Sharpness 4. Click OK.
Desaturate that layer (Image/Adjustments/Desaturate).
Be sure that your default colors are black and white (just hit “D” to reset them).
Make the upper layer visible again, click on it to target it and run Filter/Sketch/Graphic pen. Try  Stroke Length 15, Light Dark Balance 10-20, and Right Diagonal for the Stroke Direction.
Set the layer mode to Overlay. Duplicate this layer if you want a brighter result.
For a softer look, use Filter/Blur/Gaussian blur at a low setting on either or both of the layers.
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The following (from www.permadi.com) is a more involved technique, but for those comfortable with Photoshop, the results can be very pleasing.

 

[Mailboxes]
Open an image. Duplicate the background and sharpen it as much as possible without turning the image totally strange.
Be sure that the default colors are black and white (hit D).
Duplicate the sharpened layer and run Filter/Sketch/Graphic pen, with 4 as the Stroke Length and 50 for the Light/dark balance. The Stroke Direction can be right diagonal.
Hide that layer. Duplicate the sharpened layer again and run Graphic Pen again, but change the Stroke Length to 10 (other settings remain the same).
Hide that layer, dupe the sharpened one once again, and run Graphic Pen with a Stroke Length of 15.
Put the graphic pen layers in descending order for Stroke Length (the longest stroke at the top), turn them all on, and set each of them to 50% opacity.
Add a new layer below the 3 graphic pen layers and fill it with white.
Add a Hue/Saturation adjustment layer set to Colorize at the top of the layer stack if you want to add a tint.
You can add a Brightness/Contrast adjustment layer if needed.
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As you experiment, remember that not every technique will work well for every photo, and not every photo will work well as a sketch. After some practice, you’ll start to recognize which images lend themselves to being turned into drawings, and you’ll start to feel like a new kind of artist! You might try using a mask to have only a portion of your image “sketched,” with the rest left in the original color. As a finishing touch, try flattening a copy of your final sketch and apply Filter/Texture/Canvas.