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PAL_Houston
30th Apr 2012, 10:54 PM
I can never seem to get enough depth of field in my layout photos. I have a DSLR with 55mm lens, and with enough light and with the camera on a tripod I can go with apertures up to f32. But the layout room constrains what I can do about proximity to the subject.

Seems like a few years ago I read about some software that would automatically combine multiple images that were each focused to different depths into a single image that had good focus from the front all the way to the back of the scene.

Does this ring a bell with anyone? What software is that and what have you been able to do with it?

Are there a set of guidelines or "best practices" for using it for layout photography?

Thanks!

TwinDad
30th Apr 2012, 11:00 PM
Google "Helicon Focus"

That's the software I keep seeing folks using in the MR "Trackside Photos" shots where this has been done...

I've never used it myself.

PW&NJ
1st May 2012, 02:40 AM
The other thing you might try Googling is "focus stacking" (which is what Helicon Focus does). There are other software applications out there that can do this, including some free ones, or you can even do manual focus stacking using an image editor like Photoshop or GIMP (free, similar to Photoshop, www.gimp.org (http://www.gimp.org)).

Basically, here's what you do:



Set up your camera on a tripod and arrange your shot.
Set your aperture as high as you can get it (note: this may require setting your camera to something like "aperture priority" mode).
Set focus to manual, then proceed to take several photos of your shot, adjusting the focus from the closest detail, shot-by-shot to the farthest detail (the background), being careful not to move the camera or adjust the zoom in the process.
Then you import those photos into your preferred image editing software (note: as long as it supports layers and alpha channels, which means transparency on the layers) in order from front to rear (layered top to bottom).
Using the "lasso" select tool (the tool that lets you select any shape), select the areas just before the layer goes out of focus (in other words, make your selection where it's still sharp) and delete that part of the layer, then choose the next layer down and do the same thing.
Repeat this process until you reach the background layer.
Check each layer again for any trouble spots and clean up if necessary, then flatten your image.


Here's a quickie example of this process. The first shot is of my old Bachmann Amtrak Metroliner (N-scale, of course), using an aperture of F8 (I'm not using a DSLR so that's as far as I can go).

http://dev.checkertaxistand.com/photos/other-locos/Metroliner-before.jpg

Notice how the front is nice and crisply focused, but that trails off to a blurry background. Even the ties get blurry. Now here's the same shot with stacked focusing applied:

http://dev.checkertaxistand.com/photos/other-locos/Metroliner.jpg

MUCH BETTER! Now this was just a quickie example with no special lighting, was only four shots, and I handheld the camera, but I think it gets the point across well enough.

Hope this helps. Enjoy!

TwinDad
2nd May 2012, 02:57 PM
Thanks, PW. It hadn't occurred to me that this could be done manually... :)

Zombinowski
13th May 2012, 08:41 PM
There is also a freeware called CombineZM. It is a stand alone program
http://hadleyweb.pwp.blueyonder.co.uk/CZM/News.htm

Couple of examples:
11 Photo stack:
http://gallery2.mambalam.net/main.php?g2_view=core.DownloadItem&g2_itemId=9658&g2_serialNumber=2

8 photo stack:
http://gallery2.mambalam.net/main.php?g2_view=core.DownloadItem&g2_itemId=9660&g2_serialNumber=1

code40
13th May 2012, 09:48 PM
Excellent photos Ganesh - the extra depth of field does justice to your scenery. Unfortunately, CombineZM appears to be Windows only so that counts me out. :(