Newbie question about Focus Stacking

[JLew24asu]

it seems to me that the closer you go, the smaller the focus area becomes? thus the need to focus stack?

[LordV]

Nearly correct - its the depth of focus that becomes narrower as the magnification goes up. This coupled with diffraction softening getting worse at higher magnifications makes focus stacking a useful but not essential technique.

Brian v.

[kwhunter]

it seems to me that the closer you go, the smaller the focus area becomes? thus the need to focus stack?

This is correct; now, if you want to hold the scale at 1:1 you need to move the camera in small increments and for that you will need a macro rail. Then stack the shots using one of the available stacking programs.
Here's an example, shot at 1:1; to cover the whole DOF over a 10 mm distance I moved the camera on the rail by 1 turn of the micrometric screw and took 14 shots. The image is cropped as the slide has some play and the margins were blurred after staking.

http://i273.photobucket.com/albums/jj222/kwhunter/sks/New-Out99999_99998_web.jpg

[JLew24asu]

14 shots! damn. thanks for your expertise guys.

[pturton]

The depth of focus gets less as the magnification gets higher as already mentioned. Focus stacking is tool used to over come this lack of DOF. For stationary subjects, a macro rail makes the incremental focus point change easier than any other method. But for live and active subjects, handheld focus point change can be achieved if done quickly.

The jumping spider image I posted in this thread was a stack of 2 images shot handheld with my MP-E 65 at 4X, f/11. At 4X the DOF is only 0.25 mm @ f/11 with the MP-E 65. By stacking 2 images, I could increase the apparent DOF to about 0.4 mm. Before the next shot and the jumper had jumped onto my lens hood.

http://photography-on-the.net/forum/showthread.php?t=682202

[kwhunter]

14 shots! damn. thanks for your expertise guys.

Just counted, they are 12 actually.
Because the tripod-slide-camera system wasn't absolutely rigid, after alignment/magnification adjustment the outer edges of the image were blurred and I had to crop it.
Here's the 'raw' image as processed by the staking program:

http://i273.photobucket.com/albums/jj222/kwhunter/sks/New-Out99999_99998.jpg

[DQE]

There is a forum mostly dedicated to high-precision focus stacking that you might enjoy. These people use 50-100 or more photos in their stacks to produce some astonishing images.

Here's the URL:


http://photomacrography.net/forum/viewforum.php?f=27

[kwhunter]

There is a forum mostly dedicated to high-precision focus stacking that you might enjoy. These people use 50-100 or more photos in their stacks to produce some astonishing images.

Here's the URL:


http://photomacrography.net/forum/viewforum.php?f=27


Great, thank you!

[sagarmatha]

kwhunter: what are your equipment for doing these stackings?