Grahame Loc: Fiji

I've also used both methods and found that the focus barrel is fine for subjects the size I generally do. This example was roughly 25mm width. Somewhere I have a couple of gifs I made showing the difference in perspective between slices between the two methods.

(Download)

PlymouthWoodworker Loc: Plymouth, MA

Thanks Gene51. Very nice composition.

garrickw Loc: Wyoming Mn.

what camera are you using?

fetzler Loc: North West PA

The method that you want to use depends on the magnification. For images up to 1:1 (if you use a macro lens capable of focusing to 1:1) one can use lens focus. Camera is fixed and the lens focus adjustment can be used. To be successful you must have an adequate number of frames. If you have a Nikon or Cannon camera Helicon remote software can be used to automate this process. You will tether your camera with PC, phone or tablet (Android). I usually find it best to use more exposures than Helicon recommends. If the magnification is greater that 1:1 then you must use a rail. On the Website for Zerene stacker software there is a table for determining the step size. Wemacro makes a rail that will automate this process. Knowing the step size is very important. The rail must be capable of moving in increments of only a few microns. I suppose one could do this manually with a very good rail but it would be difficult to control.

You will want to look at the websites for Helicon focus, Zerene Stacker and the Extreme macro site (http://extreme-macro.co.uk/focus-stack-processing/ )

I have both Nikon and Olympus Cameras. I must say that for high magnification work , I prefer the Olympus as vibrations are minimized. For Nikon, The mirror is raised 3 seconds before each exposure. (option d4 on my camera)

My Olympus camera allows for Focus bracketing which could be very handy for outside work. The problem with this is that the focus step sizes are not well documented so a lot of trial and error is necessary. There is a Helicon tube that gives a similar feature to Nikon and Cannon lenses.

For landscape work. Turning the focus on you lens is adequate. When in doubt take a few more pictures.

Harvey Loc: Pioneer, CA

Macro was a challenge for me - so I studied it quite deeply before purchasing the economic tools needed to accomplish my goal, tubes, bellows, 4 way rail and reverse rings for lens- it worked well for 1:1 up to 5:1 images - then came the stacking which I found so much easier than I imagined - yes I have only focus stacked with rail shots and darn happy with the results.

sippyjug104 Loc: Missouri

Linda mentioned my focus stacking so I'll share my opinions and experiences, both good and not so good. Essentially there are three ways to change the focal point, move the camera toward the subject with the focus point set, move the subject toward the camera with the focus point set and third is to keep both the camera and the subject locked in position (as much as possible) and change the focal point with the lens.

What may work best could depend on the lens used. Microscope objectives and reversed mounted lenses do not lend themselves well for adjusting the lens focal point. Many lenses used do not even have that ability. The goal is NOT to touch the camera. The slightest movements or vibrations are difficult to contend with and may result in blur and ghosting.

Helicon Focus Tube is a fantastic device for it changes the focal point of the lens and it is very, very good for focus stacking images in the field (it is great for studio work too). It would surely be my choice if I were to take to the field and it eliminates the guesswork of how far to manually turn the lens focus ring.

The distance of the "steps" are dependant on the camera sensor size (full frame, crop, etc.), amount of magnification and the f/stop. As magnification increases the distance of travel between shots decreases. When using microscope objectives at 10X, I am in the 8-micron per distance step for each shot in the stack and the number of images number in the hundreds.

Typical macro lenses do have some degree of depth of field although it may be very shallow. Flat dept of field lense have virtually no depth of field so each photo it takes is a tip of a hair thin. When venturing into that domain, computerized focus rails are a necessity and no vibrations can be tolerated. I have my camera rig mounted on a concrete floor on a 500-lbs laboratory cabinet with two inch thick granite and vibration isolators on the base of the cabinet and under the granite. I shoot in the mirror up mode and I pause 2-seconds between shots to let any transient vibrations settle. I operate the camera with the PC and after setting up the session, I never touch the camera and when I hit "start" I leave the room and all lights are out except for the subject's illumination. Of course it is not necessary to go to these extremes unless the goal is high levels of magnification which to me is between 10X to 20X.

Diffraction also increases as magnification increases so finding the sweet-spot of the aperture will vary from lens to lens. Reversing lenses and putting combinations of lenses in series plays into this as well. Extension tubes, helicoids, and bellows all affect the amount of light that travels through the lens and also impacts diffraction. Illumination and diffusion of light is both a joy, a pain in the butt, and a science in itself and it can make or break the resulting image.

Of course there is much, much more and if you would care to message me I would be happy to share as much as I can. If you'd like to see some of my work, here's my Flickr link https://www.flickr.com/photos/153096150@N05/?

rjaywallace Loc: Wisconsin

Nicely done shot of the flower, Gene!

fetzler Loc: North West PA

I concur with sippyjug. Vibrations are killer. I have my subjects placed on a sheet 1/4 in steel so my set up is not a good a sippyjug's.

Harvey Loc: Pioneer, CA

Compared to yours mine would be on an innerspring mattress. LOL

sippyjug104 Loc: Missouri

Thanks, and I found a great source of granite to be from the fellows that make kitchen countertops. Most often they cut out a piece of granite for the kitchen sink to drop into or hang under. That "slug" of granite is available at a very reasonable price. I paid $25 for mine. It's really..really heavy so be careful not to drop it on your toe. My laboratory counter is an old beast taken out on a jobsite. It has a one-inch thick acid resistant synthetic stone top which is why it weighs so much. I put high compression isolation pads down and then put two of the granite cut-outs on top of the counter with pads between the two of them.

My macro platform converts from horizontal to vertical and it has high compression rubber feet that I silicone adhered to the top granite slab.

No one need go through that extreme, just mount the camera on something that has mass and don't touch anything while shooting. Use a remote shutter release and set the camera timer to release after a few seconds. Most importantly, for DSLR users, shoot in the Mirror Up mode to avoid internal vibrations from "mirror slap".

bioteacher Loc: Brooklyn, NY

Do you have the link for the Helicon Focus Tube?

sippyjug104 Loc: Missouri

Absolutely, and there are several on the forum that use it.

https://www.heliconsoft.com/heliconsoft-products/helicon-fb-tube/

PlymouthWoodworker Loc: Plymouth, MA

Garrickw, I’m using a Nikon D7100 with a 40mm f/2.8 macro lens.

PlymouthWoodworker Loc: Plymouth, MA

Thank you fetzler, Harvey, and sippybug104 for your comments and suggestions. My needs are less demanding than most of yours as my magnification is generally much less than 1:1, and my subjects are much larger than insects. I do use a remote release, and will probably start using mirror lock-up as well.

Mark Sturtevant Loc: Grand Blanc, MI

There will be changes in perspective between foreground and background no matter your method of changing the focus. There is no way around it. But the image can still be stacked, with touch-ups, long as objects in the foreground are in focus while background objects are out of focus, and vice versa. Then, the stacking software will know to ignore what is out of focus as it stitches the picture together. Problems arise when bits of foreground and background are both in focus. To help minimize this issue, the aperture is set to be rather wide so the depth of focus is shallow. The perspective problem is worse if the camera is not level, so the rail movement 'pans' over the subject as pictures are taken. There is another artifact you will run into called 'halos'. You will see them. They are a somewhat different problem.
These artifacts and others are dealt with with the stacking software. Photoshop software for stacking is pretty good, especially for very simple stacks, but it does not so easily handle certain artifacts. Zerene Stacker and Helicon Focus are dedicated stacking software and they have powerful tools to quickly deal with the various artifacts. They are easy to learn too. I happen to use Zerene, and the video tutorials are very easy to follow.

Finally, not all stacks are 'finished' by the stacking software. There are artifacts that may need to be fixed in programs like Photoshop by using the cloning, healing, and copy and paste tools. Subterfuge and mis-direction are all part of the process.