Blended images

I've seen tutorials for blending 2 images shot at different exposures in order to expand dynamic range short of a full HDR manipulation. What I want to do is blend 2 images shot with the same exposure but focused at a near and far focal point in order to expand depth of field. I have seen a few photos done this way as an alternative to using hyperfocal distance focusing which I have not found to be very satisfying. So my question is, how do you do this without upgrading to CS4 to get the new auto-blend function? Thanks--Larry

Put both images in a single PS document; use a layer mask on the upper layer to hide the part you want to show through from the layer beneath.

On the layer mask, a very large, soft-edged paintbrush usually works the best.

CS4 also has a blending tool to do this as well. It is supposed to be pretty decent, but I am running CS2 so I haven't used it.

I've used Helicon Focus, which works well but has some problems with moving objects (like wind in a landscape). That is not a surprise - actually, it would BE a suprise if any software got moving tree branchs correct.

You do it almost exactly the same as an exposure blend, as Nat noted.
Here's a tutorial for a simple blend to refresh your memory.

Thanks guys, I have several tutorials on blending images using layers and masks, just was wondering if there is a different way that avoids dealing with masks. Sounds like that should do the trick since it is mainly a foreground/background separation. I took several different sets of exposures on friday of the same scene, some using hyperfocal distance and others by just changing the focal point. Overall the twin exposures gives much crisper foreground and background than using the hyperfocal distance alone. I think one issue might be that there is just a hairsbreadth distance between 1m and infinity on the distance scale of the Canon 10-22mm so there is very little leeway. Anyone have any experience using hyperfocal focusing with that or a similar ens? Tips welcome--thanks--Larry

I can't answer that particular question.

However, here's a tip on matching the slightly different image perspectives that you achieve by changing focal points.

I also use the same method as you to achieve a true (and higher quality) hyperfocal range of focus (no more f22!). Here's how I match images using different focal points:
Assuming that you're using CS3, then stack the images on top of each other (Move tool + Shift key).
In the Layers palette, select both the Background and the new layer created when you did the stack.
Edit->AutoAlign Layers.
Choose 'Auto' in the 'Projection' field.
Let CS3 do it's thing, and voila!...you'll have both images stacked in perfect alignment and ready for you to work with.

It took a few tries before I figured out a couple additional steps. First, don't open the images to be blended as Smart Objects--Auto-align doesn't work with them. I had to bring both files into PS then overlay them, then do Auto-align. After that it was pretty easy to create the layer mask and paint out the section of the top layer that I wanted to bring up from the bottom layer. In this case I made the foreground image the bottom layer and the rear image the top one--that way I only had to paint out the lower 1/3 of the top image thus making the sharper foreground image visible. I've posted it below. Thanks again for the help guys--Larry


<img src="http://mywebpages.comcast.net/flydoctor/Little_Devil.jpg"

Larry,

On my ESS post from about a week ago, I blended two images, one focused for foreground and one for background. I simply used a gradient mask to blend. I made it easy on myself by using the area of blurred water motion (long-ish exposure) beyond some underwater foreground detail. Of course the gradient blend doesn't work as well if your scene is something like looking through vegetation or you have tall foreground objects. I'm curious to view your post to see what you've done.

EDIT: I just saw the image you added above. It looks good! I think the gradient tool would work here as long as the rocks at the right were double-checked. Nice work.

Helicon Focus is an application used for macrophotography that blends images made in different focal planes. I've played with it on some macros and it's very interesting.

http://www.heliconsoft.com/heliconfocus.html

Looks great, Larry!

Good discussion, guys...

keep in mind that although there are really handy tools available to "help" automate the workflow, whenever you need to make a perfect composite of multiple images for any reason (as in this instance of bracketed-focus blends) there is no good way to completely avoid masks, and thus, Photoshop.

Using layers and masks in Photoshop, you really can accomplish anything you can conceive of for your photographs.

All the newest plug-in/add-on software is meant to take away the need to learn layers and masks. IMO, bad idea.

Some of this can be automated; usually with simple actions and scripts.

But when you need to merge multiple images for any purpose, there's no such thing as push-button perfection.

Nat--that is a very good point. One of the online tutorials on blending basically had a different way to do it so as to avoid layers and masks. However, I really liked the control I had in placing the dividing line between the two images. I now feel very comfortable with this technique and I'm sure I'll now experiment with other situations where a layer mask will work--Larry

I would agree that using Helicon Focus is a viable way to do this. A number of years ago I suggested to the developer of Helicon Focus that it could be used instead of hyperfocal techniques to get decent infinite focus landscapes. I provided a sample which, I believe, is still linked on the Helicon Focus forum.

Also, if you want free software which does the same thing and does it very well, you may want to look at CombineZP which is freeware by Alan Hadley in the UK.

You can download it and find out about it here:

http://www.hadleyweb.pwp.blueyonder.co.uk/CZP/News.htm

Best regards,

Lin