jimjams

Please forgive such a beginner’s question, but I have tried searching everywhere for an answer and not found a definitive answer. Perhaps it’s too obvious a question..

I have a 2-way focusing rail and my Canon 70D camera. I wish to take a series of photos, indoors, of an inanimate small object, for instance a button or a leaf.

I set my camera on a tripod and using live view I focus on the point nearest the camera and take a picture.

Then what...
Do I use the rail to move the camera in a very small increment nearer the object AND AT THE SAME TIME re-focus on a point SLIGHTLY further back from the initial shot for my next picture?

OR

Do I not alter the camera focus from it’s previous focus setting in any way but merely use the rail to move the camera forward?

It’s this aspect that I’m stuck on; whether I have to refocus on a further back point once I’ve repositioned the camera via the rail.

jackm1943 Loc: Omaha, Nebraska

I have read from at least two sources that there are basically three ways to take focus stacking images:

1: Good: Set the camera on a focusing rail and move the camera and lens together one step at a timre by moving the focus rail.

2: Better: Hold the camera still (tripod, focus rail, hand-held, etc) and turn the lens focus ring a tiny amount between images. You could use the focus rail to help get the the camera in position and getting the first image in focus, then take the remainder of the images by turning the focus ring.

3: Best: Hold the lens still and slowly move the camera between images.

I think #1 might be preferred by those who do extreme micro style work. Some use automatic rails that move the camera just a fraction of a millimeter at a time.

#2 is what I normally do and, with care, it can be done hand held. Some cameras have the ability to do this built in, and there is a piece of equipment (Helicon focus ring) that will work to do this on some cameras. This method is probably best for "close-ups" up to 1:1. Works great for landscapes also where just two or three images are needed.

#3 requires some equipment I have been unable to find, namely a bellows rail that holds the lens in place but lets the camera move, just the opposite of what bellows available today do.

newtoyou Loc: Eastport

A bit vague on purpose. No info on gear. What is your goal?
Are you using a stack program?. If so, go back and follow sippyjug and his methodology. On True Macro site.
If just shooting, I move the subject. Mounting the specimen on the rail, not the camera on the rail may work. Get the camera on a table mount, eliminate the tripod. Some wood scraps, a 1/4-20 screw and a bit of ingenuity are all you need.This in the 'studio'. In the field a different set of problems.
Those rails are too loose. If on an angle, like to jamb with shift in camera weight.
The gist is, no one way. Shoot, experiment, see what works for you.
This field is open to invention. Going back in macro threads is your best start.
And enjoy it,another world.

Mark Sturtevant Loc: Grand Blanc, MI

I don't do this sort of thing but jackm & newtoyou has it well explained for focus stacking. Not sure if that is what you were after, though. There is no need to move the camera closer and refocus. The action of moving the camera changes the focus point to a slightly different but partially overlapping focus point.
You might be just asking about taking a series of pictures from different views and angles, though. Not sure.

If this is about focus stacking, others can step in and advise from experience I don't have. Issues that need to be addressed are the aperture setting and lighting.

jimjams

Jackm and Bill, thank you for replying. You have covered issues that are helpful.

Mark - many thanks, that is exactly what I wanted to know... such an ignorant question I know but my query was whether I moved the camera as well as refocusing...

This is quite a learning curve for me and I appreciate all your help.

jackm1943 Loc: Omaha, Nebraska

Keep after it jimjams. It's much easier than it sounds and you can quickly get addicted to it. There are any number of YouTube videos our there that could be helpful.

newtoyou Loc: Eastport

I have not, as yet, stacked any images. I was only looking for ways to shoot small insects. I use a variety of lenses, tubes, an MPE65 canon and a group of off the wall ways and techniques to that end.
Then along comes stacking. Sippyjug has mastered the simple way and moved on to precision work of AMAZING detail.
The cost of elaborate gear is beyond me, so I am working on a way to move in precise increments that can be made by most with a bit of handyman skill.
The stacking programs are free, or inexpensive, I understand.
When done, I will publish a plan and material list.
The two best tips, tho, are"practice, and keep at it, it does get easier.
Bill

rwilson1942 Loc: Houston, TX

From what I can tell, those of us who do focus stacking and use a focusing rail, use the focusing rail to move the camera and lens forward and do not change the focus setting of the lens.
I start by focusing on the point nearest the camera, then using only the focusing rail, move the camera and lens forward in small increments until I have photographed all of points I wish to be in focus.

jimjams

Brilliant Rick - and presumably I have it on manual focus? I thought using live view would be more accurate..

rwilson1942 Loc: Houston, TX

Yes, manual focus.
I use manual focus for all of my macro work.

Mark Sturtevant Loc: Grand Blanc, MI

I will just stick my nose in here to bring up some other points. I don't do this sort of photography, but I read a lot of descriptions from those who do, so I am 'book trained', not field trained on this. Still, I am pretty sure this is sound enough advice.
1. You can move the camera on the rail, or keep it well locked down and use the rail to move the specimen. Both are commonly done, but moving the specimen is sometimes found to be less trouble if the camera rig is big and not balanced. Moving either of the camera or specimen creates vibrations that need to settle down before the next picture is taken, and if the camera is heavier and more off balance than the specimen, then moving the specimen can result in fewer vibrations and it settles down faster. Just consider moving the specimen. It might be the better choice.
2. Aperture. The advantages of focus stacking of course include greater depth of focus after the images are stacked, but also the image can be amazingly sharp. To get the sharpest images, the lens should be at a wider aperture, like f/6 or so. In general, lenses are at their sharpest around there. Of course that means extra shallow depth of focus, but stacking takes care of that.
3. Lighting. Each exposure probably will need supplemental lighting so that the shutter speed is not forced to be too slow (slower shutters --> more effects from micro-vibrations). People generally favor using a continuous source of LED lighting, or, if they get fancy, they use strobe lighting. Using a regular flash can be a problem since the light intensity can vary from exposure to exposure, and the batteries can become taxed and even overheated. People can use camera flashes, but that is one more thing that can go wrong.
If you are moving the camera, you do not want to have the light source be attached to the camera since then that changes the lighting for each picture.
4. ISO. Lower ISO is favored, like ISO 100 or 200. This is do-able since the the apertures are pretty wide, and you will likely be using supplemental lighting. The lower ISO means virtually no sensor noise, again contributing to a clean, exceptionally sharp picture in the end.

Nikonian72 Loc: Chico CA

Focus Stacking Instructional Videos: https://www.uglyhedgehog.com/t-166660-1.html

rmpsrpms Loc: Santa Clara, CA

Best way to move the camera and lens for focus stacking depends on the magnification. Obviously, moving camera and lens together to do landscape work makes no sense, unless your focusing rail is massively long (maybe use train tracks?), so using the lens focus is the only practical method. As mag increases, it starts to become practical to move the camera and lens together perhaps around 1:2 magnification. Perhaps starting at 4:1, the step sizes required for stacking become quite small, and are difficult to do manually. Around this mag it starts to make sense to keep the lens fixed, and move the camera instead. This has the effect of allowing larger step sizes for the same change in focal plane, so reduces the sensitivity and makes manual movements more practical.

I used to have a handy chart that talked about these methods and their appropriate ranges, but the above gives the idea.

One problem with moving just the lens (low mag), or just the camera (high mag), is that the magnification changes a fair amount between shots. Focus stacking software is capable of adjusting for magnification changes, x and y shifts, and rotation between shots, but it's better from a sharpness perspective if there are as few shifts as possible. Re-sampling images always reduces sharpness, so if you can shoot your stacks such that the only thing changing is the focus between shots, it will produce a sharper image. Not too practical handheld, but in-studio it can be done.

jimjams

Mark, again you bring to the beginner (me) salient points that are great and I do take on board this is 'read' rather than 'practice' born. Nonetheless, sometimes it's the way something is explained that can help or hinder a person's initial foray into new territory.

Ray, I'm taking on board the very small increments required for best stacking results, plus the comment re ensuring as little changes between shots as possible...thanks for the input.


Today I have tried taking shots of an onion skin, with added lighting (a small 6 led Manfrotto light) and using the rail. Your comment re a lower iso Mark, is noted though and I think I'll need more light than I currently have.
I haven't been overly successful as yet in learning how small an increment I really need...hampered big time by the fact that due to disability I had failed to take the requirement of comfort as I was stuck for a long time in one fixed position.

Re stacking. I did put the photos I did get, into lightroom but only found a merge (HDR) option and wasn't sure if that was what was needed. Further research needed.

Needless to say, I 100% appreciate the comments and help. I WILL persist, I will get the hang of this. Health does not always permit me ease with anything I do, but I love what people achieve in the 1:1 macro field and hope for some success.

Mark Sturtevant Loc: Grand Blanc, MI

There is HDR merging, but you want focus stacking.
There are several videos on YouTube about stacking in Photoshop but I don't see any in LightRoom. Perhaps that program does not do it.