Focus Stacking

[P_Budzik]

Here is a fairly complete discussion about depth of field for photographing scale models and there is a step by step instruction for using HelioFocus for focus stacking ...

 

https://www.youtube.com/watch?v=yXOsZVbclPI

 

 

[modeller_masa]

Hello, It is good to know that my old hobby helps my current hobby. I made cheaper gear for focus stacking - model photography.

 

I bought 4 casters. 'Authentic' photo equipments including carbon fiber rail starts at $120, but these wheels are only 40 cents per each.

 

The (wood) stand size depends on your choice. If you place it under the target model, you may save more plywood panel, but it is hard to take a full-shot because the model moves.

 

The most challenging difficulties are chance of success and your patience. I used to take photos with a very high resolution camera and closed apertures, but this challenging method allows some unique angle of shot. 😎

 

 

[trippwj]

On 10/23/2021 at 4:59 PM, glbarlow said:

Canon users are out of luck altogether. 

I realize that I am a few years late to the party, and acknowledge that my response, as a Canon EOS 90D user (formerly a Minolta devotee) may have missed a similar reply.

 

My Canon does allow for what Canon refers to as "focus bracketing" - same as focus stacking or focus shift shooting.

 

[James H]

Focus stacking is a doddle.......if you use Photoshop!

[gsdpic]

8 hours ago, James H said:

Focus stacking is a doddle.......if you use Photoshop!

And with that, google sees a small spike of "doddle definition" searches from the USA

 

dod·dle

noun

informal•British

noun: doddle

1. a very easy task.

   "this printer is a doddle to set up and use"

    

    

[glbarlow]

Nikon’s Focus Shift Shooting (with mirrorless electronic shutters) and LightRoom /Photoshop functions have improved and are now quicker and easier to do since this thread started. Still a bit of work to get a single image, but short of complex lab equipment it’s the best way to get that one image. That one being one, I can’t image taking the time to create a gallery of them.

[Dziadeczek]

I don't know if you guys are aware that there is a free and very simple focus stacking program online.   Focus stacking online - free online focus stacking software   Only two steps required.

 

Edited August 4, 2023 by Dziadeczek

[kurtvd19]

Thanks, I will give it a try.

[Kevin-the-lubber]

I have an Olympus OM-D E-M5 II which has built-in focus stacking that includes processing the image in camera. I did some tests to compare this with processing via Helicon and various free programmes and decided the difference was negligible, certainly at the sizes I work to i.e. 12 x 10 prints. The camera gives you a choice between the built-in stacking, which takes and combines 8 shots, or stacking for off-camera processing, in which case you can take as many images as you like.

 

For reasons unknown Olympus restrict stacking to only a few particular and expensive lenses, but there is a free firmware hack on the web that allows you to over-ride this. 
 

Now, the reason I haven’t included any example pics is because having the right tools is only half the job and, while stacking is indeed a doddle, getting it right takes a bit of practice. I wouldn’t claim to have reached that point with my model photos yet. Nor my modelling for that matter!

Dziadeczek, are you running a build log anywhere? I ended up here because of your ‘at a glance’ entry and I’m keen to have a closer look at your sails!

 

[Dziadeczek]

Dziadeczek, are you running a build log anywhere? I ended up here because of your ‘at a glance’ entry and I’m keen to have a closer look at your sails!

 

Kevin, I answered you privately.

[DocRob]

My camera, a Panasonic Lumix G9 has in build focus stacking, which allows to show lengthy objects or distanced objects all in focus. It's a camera mode, which allows to select different focus points as reference or use the complete front to rear area as focus stacking area. The camera takes several single pictures automatically then, which are stored as a movie in mp4 format. Finally merged in camera, stored as a single picture, you get what you wanted, voila. I had good results, even without a tripod.

 

Cheers Rob

[DonBMichigan]

I have a few Olympus cameras, and have tried a number of different methods of focus bracketing: in-camera; using a tripod and rail; moving the focus ring manually and taking multiple shots; and using the Olympus Capture software to move the focus at each shot with the camera on a tripod. You can also just use the touch screen and tap along the image of the model from front to back and let the camera focus on each point. 

 

I have had difficultly getting in-camera focus stacking on my E-M1 mark II to work - with some effort, I've gotten OK results, but it's finicky IMO. 

 

I really enjoy doing macro photography and seeing how close up I can get, but I've not really tried hard to get amazing photos on the model pics I've posted here.

 

I've used Zerene Stacker or Photoshop to stack. I've found the former to work very well, but if you already have Photoshop, it's usually good enough. 

[Dr PR]

I use an older version of Photoshop (CS5) and the focus stacking works only marginally. It is especially bad where  a near object, like a rope, passes in front of a more distant object. The distant object will be blurred slightly on either side of the closer object.

 

I have to do a lot of touch up, but I get acceptable pictures. My cameras don't do focus stacking internally. That's something to look for in future purchases.

[gsdpic]

11 hours ago, Dr PR said:

It is especially bad where  a near object, like a rope, passes in front of a more distant object. The distant object will be blurred slightly on either side of the closer object.

To a great extent, I think that is a limit of focus stacking.  Imagine (oh, wait, you don't have to imagine, there are pictures below) an object, say a strip of basswood, sticking up in front of a piece of graph paper.  It should be enough to take two photos, one focused on the stick and one on the paper, to do a focus stack.  But when focused on the paper, the stick becomes a blurry smudge that is larger than it is when it is in focus.  So the bits of graph paper that are immediately next to the image of the focused stick are at least partially obscured in the graph paper image.  So, when the focus stack is done, there are parts of the graph paper that are not clear and unobscured in either image.    I did the below experiment, all images taken with a 180mm macro lens about 5 to 6 feet from the objects, at f/3.5).  The stick and graph paper were about 12 inches apart.  Note that at 6 feet, f/3.5 180mm, the actual depth of field is less than one inch.

 

First, the two source files, focused on the stick and on the graph paper.

 

Now, the results with photoshop (the current 25.0 release).  You can see it struggled.  It is possible that I did not quite nail the focus on the stick but I thought it should have been close enough.  Photoshop just creates a mask to combine the two images so everything here is from one image or the other with no blending.  It missed much of the image focused on the stick, and you can see the places where it got the focused stick, the blue lines of the graph paper fade out near the stick, due to the blurry smudge in the graph paper image.

Here's the results from Helicon Focus 8.2.2 (also current version).  You can see it did a much, much better job, but the graph paper lines still fade out next to the stick.  Interestingly, you can also see through the stick to the graph paper lines behind it to some extent, much like in the source image that was focused on the graph paper.

I might have to try again with better focus on the stick to see if that helps photoshop any.

 

[Dr PR]

Very good explanation.

 

Another issue, especially with macro lenses, is that as you change focus the area included in the photo changes size a bit. So any particular object will be different sizes relative to the overall frame size in different images. Photoshop has a "Edit/Auto-Align Layers" function that resizes each layer so objects common to all are the same size - and maybe "stretched" a bit to the same overall outline.

 

But the result is that the outer edges of the stacked photos can be blurry. I always back off enough that the photo frame is a bit larger than optimal, and crop the edges in the final picture.

 

Photo stacking isn't perfect, but you can get extraordinary depth of field if you use it correctly and don't mind doing a bit of post-processing touch-up.

[BrochBoating]

Probably missed this being said but for reliable focus stacking move the camera not the focus. 

[Dr PR]

That might work iff the camera was mounted on a rail and could be moved in a perfectly straight line to and from the desired image center. However, I can't see any advantage to doing that over just keeping the camera in a fixed position and changing the focus point of the lens.

 

If you change the distance of the camera to the object being focused the image of the object will change size in the images relative to other objects. Also, the relative angles from the focal plane to objects will change. Either effect will cause problems with focus stacking.

 

Any slight side to side or up and down motion (camera or object) will play havoc with the stacking software - I speak from lots of experience shooting photos of wildflowers where wind can change the relative position of the flower in successive photos. It changes the view angle, so objects that are hidden by closer objects in one photo will be "unhidden" in subsequent photos. Even if these things are out of focus they will appear in the photo because there is no matching in focus image in other pictures.

 

If the camera moves all bets are off what the software will do, but most often artifact I see are multiple images side by side of the same object. If this problem isn't too bad it can be corrected by editing the picture. But you really have to want the photo to spend that much time on it!

 

Here is a recent focus stacked image made from twelve pictures. The camera was fixed on a tripod and the lens was focused successively from the closest object to the more distant.

 

Each image was 6000x4000 pixels, but successive photos captured slightly larger or smaller areas of the model due to changing the distance to the focus point.

 

The images were first aligned, which stretches "smaller" images or shrinks "larger" images so the images of individual objects are the same size in all photos. Then the images were stacked.

 

The image was slightly cropped to remove the blurry edges that result when one image area is larger than another and there are no matching in focus objects in the surrounding part of the larger images.

 

The main problem I see is a result of the way the software decides what is in focus and what is not. An example is the prominent vertical fish tackle rope in the foreground. It is in focus in closer images, but the edge of the deck house in the background was out of focus in those images. The deck house was sharply focused in the distant images where the fish tackle was out of focus.

 

When the images were stacked the deck house edge was out of focus for a short distance on either side of the rope. The software chose the blurry edges near the rope instead of the sharp edges of the deck house. I cleaned this up by editing the image.

 

If the camera had moved vertically or horizontally (or both) there would be multiple edges for every object running from near to far in the picture. It would be a real mass to try to clean up with editing.

Edited November 17, 2023 by Dr PR

[BrochBoating]

Can be done by hand but should be done with tripod and rail. That way a true macro lens can be used and allows for the changes in aperture and microscopic depth of field that brings. Even cheaper rails will usually do with decent technique. 
Processing with Lightroom or Photoshop is simple, if time consuming too. 
Not a difficult technique. Lighting is likely to be more difficult. 

[Dr PR]

BB,

 

You are quite correct. Sorry I misunderstood you. I do use a rail for what I would call extreme macro photography.

 

This is a Nikon two rail bellows unit. It is very sturdy. The older manual 105 mm macro lens is attached to the front of the bellows unit and the camera body is attached to the rear - using an extension tube here because the hand hold projection on the digital camera body would otherwise contact the bellows unit frame (the modern digital camera body and ancient film camera bellows unit weren't designed to work together).

 

Because there is no communication between the camera and lens a manual diaphragm control (between bellows frame and lens) and cable are necessary. The lens diaphragm is adjusted manually. The camera body is set to Manual mode (which I always use anyway).

 

This assembly allows the compensating focus/ frame control you are talking about.

 

But the primary use for the bellows is high magnification macro photography. As shown here it allows the distance between the camera and lens to be varied. The greater the distance the higher the magnification.

 

The macro lens produces a 1:1 scale (life size) image on the photo element (most lenses create approximately 1:4 scale images, or 1/4 life size). This is called the reproduction ratio.

 

With the bellows fully extended I have produced 5:1 scale images (5 times life size) on the photo element. It is useful for very tiny flowers (1/8 inch or 3 mm and smaller).

 

However, such large magnifications aren't necessary for photographing ship models where the life size object is many times larger than the photo element. For whole model pictures I use a f 2.8 16 to 80 mm zoom lens (0.25 x reproduction ratio) that will focus to about 14 inches (350 mm) from the film plane (about 9 inches or 229 mm from the end of the lens). For smaller parts of the model I just use the newer automatic 105 mm macro lens (1:1 reproduction ratio) that will focus to 12 inches (314 mm) from the film plane (about 5.75 inches or 146 mm) in front of the lens). In both cases I just mount the camera on a sturdy tripod and adjust the focal point with the lens without moving the camera body. This is a lot easier and simpler than messing with the rails. The picture in my post above looking down the deck of the model was made this way.

Edited November 18, 2023 by Dr PR

[BrochBoating]

Great bellows, a set are on my list. Long focal length (I’d very much like the 180mm for specialised use)and high magnification with the bellows could make for some very interesting pictures. 

[glbarlow]

Nikon pro level cameras have a much simpler focus stacking feature, a few settings from a fixed camera position and the camera does all the work with one click of the shutter.  Of course the resulting images still have to be combined in post. 

[Kevin-the-lubber]

I just set one of the functions buttons on my little Olympus to focus stacking as I stack so frequently, meaning I can switch between stacking and single shot at the press of a button. The camera does a pretty good job of it, I just wish it didn’t keep the base images as it’s a pain deleting them.

 

However, the posts about the stick & graph paper and bellows are food for thought. The former will see me carefully inspecting those areas when I’m attempting display quality shots (macro is my forte) and the latter has me thinking I could probably use a set of those.

[Gregory]

 

2 hours ago, glbarlow said:

Nikon pro level cameras have a much simpler focus stacking feature,

Some (?) Panasonic cameras have this feature also, and the merging takes place in the camera.  Chances are, a higher end camera and post processing could result in a better result,

but I have found it works pretty good at my level of expertise.

[modeller_masa]

I'll buy a 24mm F3.5 Tilt Shift lens for my DSLR today. ($250) It is cheaper than an electric dolly rail. I thought the lens is the most simple solution for given budget.

[Dr PR]

I got that dual rail "Bellows PB-4" decades ago (~1990) at a local camera store. I think it was out of production then,  but someone found a bunch of unopened boxes in a warehouse in Portland, Oregon, and the local store bough a couple.

 

I used it with a Nikon F3 and the old manual 105 mm macro lens (that lens is the reason I switched to the Nikon system).

 

Fortunately the bellows was made way back  in the manual film camera days (nothing automatic) so it just has the simple Nikon bayonet mounting ring. This is fortunate because that mounting ring doesn't interfere with all the electrical contacts inside the mounting ring on newer digital cameras. Of course there are no mechanical or electrical connections to the lens, and none in the bellows unit. So the lens has to be focused manually and the diaphragm has to be set manually before taking a photo. The diaphragm control ring between the lens and bellows allows the diaphragm to be controlled with the cable release. The diaphragm is normally open full to allow through the lens focusing. You just set the f-stop on the lens and when you push the cable release it closes the diaphragm to the setting.

 

Be careful buying an older bellows unit (extension tubes or lenses) to work with modern cameras, because some of the older units have early electrical contacts that may damage the contacts in the latest digital cameras.

 

I think Nikon doesn't make a bellows unit any more, but someone may.

 

That old Nikon dual rail bellows unit has three gear driven moving sections. The base is a tripod mount, and this has a knob that runs on the loser rail pair to move the entire bellows unit back and forth on the tripod mount to move the whole bellows, lens and camera back and forth closer and farther from the subject.

 

On the upper pair of rails are the two frames that support the ends of the bellows, the camera mount and the lens mount. Each of these has a knob to move them back and forth on the upper rails to allow the bellows to be opened and closed. All three movement knobs have locks to prevent the movement from moving.

 

Lastly, the lens mount rotates around the vertical to provide the "tilt shift" feature for the lens that modeller_masa was talking about. This allows some pretty neat depth of field corrections for subjects  with greater depth.

 

I don't use it (or the old macro lens) much any more, but it is such an exquisitely machined, extremely high quality piece of equipment (Made in Japan) I can't bring myself to part with it! I love working with it so occasionally I will hunt for something really tiny to photograph with it.

 

For the even smaller things I have a Leitz laboratory microscope with a Nikon camera body mount. Again, it is a very old film camera body mount that works with modern digital cameras because the simple bayonet mount doesn't interfere with all the electrical contacts in the camera body. And like the bellows, the microscope mount is top quality made in Japan (I purchased the microscope adapter in Japan in the early 1970s). It allows me to go down to 1000x magnification for bacteria and such - about the limit for optical resolution.

Edited November 19, 2023 by Dr PR

[BrochBoating]

17 hours ago, glbarlow said:

Nikon pro level cameras have a much simpler focus stacking feature, a few settings from a fixed camera position and the camera does all the work with one click of the shutter.  Of course the resulting images still have to be combined in post. 

Newer ones do but older Pro cameras have no aids like this as it’s assumed you have the technique to do it yourself by that point 😉

 

11 hours ago, modeller_masa said:

I'll buy a 24mm F3.5 Tilt Shift lens for my DSLR today. ($250) It is cheaper than an electric dolly rail. I thought the lens is the most simple solution for given budget.

Be interested to hear how this goes as not sure how it would work. 

[modeller_masa]

It works like magic! I'm not afraid of out of focus issue. 😎

[glbarlow]

6 hours ago, BrochBoating said:

Newer ones do but older Pro cameras have no aids

Not sure what you’re defining as old. I first had this feature on a now 7 year old D850 and still have it on my current z7ii and two Z8s. Stacking with the camera in a fixed position modifying only the focus point is the best technique for stacking focus in my experience. Moving the camera changes the composition This is all just a matter of personal choice, whatever works for you. There is a difference between macro photography and focus stacked images, two different things. 

[Gregory]

Glenn, there seems to be two sets of approach going on here.

BrochBoating is referring to cameras that have a post editing feature built into the  camera, where you get a stacked image saved in the camera.

In my Panasonic it takes 40 images ( a video actually ) in one second, while advancing the focus from near to far. It then compiles them into a single image.

The results are so-so in my opinion, but I may not be utilizing the feature to it's greatest advantage.

 

I'm not sure what modeller_masa is on about. I think he is moving the subject and or the camera.

 

That said, knowing your photography expertise, and having seen your work, I'm sure you are using a method that produces superior results.

[BrochBoating]

1 hour ago, glbarlow said:

Not sure what you’re defining as old. I first had this feature on a now 7 year old D850 and still have it on my current z7ii and two Z8s. Stacking with the camera in a fixed position modifying only the focus point is the best technique for stacking focus in my experience. Moving the camera changes the composition This is all just a matter of personal choice, whatever works for you. There is a difference between macro photography and focus stacked images, two different things. 

 

Just about anything before the D850 as far as I know.

 

Nope macro and stacking go hand in hand for a large amount of subjects due to the microscopic depth of field at life size or above.