Archive for the ‘Helicon Focus’ Category

Alice in Telecentricity Land (plus Post Update)

August 4, 2023

In a recent blog post, I wrote …

The best advantage of a truly telecentric lens is there should be little or no “focus breathing” as the camera moves closer to/farther from the subject. Essentially that means the apparent size of the subject should remain the same. That should enable better focus stacking because the outline of the subject is constant. Source Credit: Experimenting with a telecentric lens rig (plus Post Update).

Using my clone of Rik Littlefield’s 0.8x magnification telecentric lens rig, there was little or no “focus breathing” in the test focus bracket that I created from 63 JPGs, as shown in the following slideshow.

First, a brief explanation of what is shown in the slideshow. The first frame is Photo No. 1 of 63 from the focus bracket, edited to make it black and white. The last frame in the slideshow is Photo No. 63 of 63, shown in full color.

I loaded the two photos as a stack in Photoshop. Next I changed the opacity of the last image in the slideshow to 0%, meaning the first image, now black and white, is shown completely. Then I flattened the layers and saved the output. I repeated the process, changing the opacity of the last image to 25%, 50%, 75%, and 100%. At an opacity of 100% the last image is shown completely and the first image cannot be seen.

This slideshow requires JavaScript.

Look closely at the slideshow and you might notice the subject shifts slightly to the right (from first to last slide), but nothing like the “focus breathing” that typically occurs when a non-telecentric lens is used to do focus bracketing. This means the photo composition that I saw in the first photograph is essentially the same in the last photo.

The following photo gallery features full-size versions of the same images used to create the slideshow, in order of increasing opacity.

Let’s pause to review. We know the subject should appear to be larger when the camera moves closer to the subject. But in this case, the subject appears to be the same size in both the first and last shots of the focus bracket. Why? Well, this is the point where I might be beyond the limit of my expertise but based upon my understanding of telecentricity I’d say it’s because most of the light rays that pass through the lens rig are parallel.

Things are getting curiouser and curiouser

If my [educated?] guess is true, then parallel lines in a subject should remain parallel from foreground to background.

Let’s start with a thought experiment. Think about a pair of parallel railroad tracks. Many, if not most people have noticed that railroad tracks appear to converge toward a vanishing point in the distance. The same thing happens when you photograph parallel lines. Or does it? Not when a truly telecentric lens is used to shoot the photograph! Let’s look at an example.

I didn’t have time to shoot and post process an entire focus bracket of a small plastic ruler, so I shot two quick and dirty photos near the end points of the ruler. The first photo shows the foreground; the last photo shows the background.

I could have used Photoshop to edit the images so that the vertical blue lines are aligned, but I didn’t because I decided it’s more important to show another example that illustrates lack of “focus breathing.” Plus I think it’s easy to see at a glance the lines are in fact parallel, not convergent.

Yeah, yeah — I could have and should have done a better job of posing the ruler but like I said, the photos are quick and dirty. Expediency trumps perfectionism.

Post Update

Consistent with the “quick and dirty” theme for this post, I used Apple Preview to edit the preceding photos of a small plastic ruler.

I started with the first photo. I drew a horizontal red line between two vertical blue lines on the ruler. Next, I selected and copied a small area from the bottom of the photo.

Finally, I pasted the selected/copied area from the first photo onto the second photo. As you can see the vertical blues lines are virtually the same distance apart at both ends of the ruler. Therefore my Rube Goldberg lens rig is almost perfectly telecentric.

Related Resources

Copyright © 2023 Walter Sanford. All rights reserved.

Telecentric lens rig revisited

August 1, 2023

The following composite images show the results of my first test using a new telecentric lens rig, cloned from a similar rig designed by Rik Littlefield.

Helicon Focus was used to focus stack 63 “as is” JPGs from my Fujifilm X-T3 mirrorless digital camera (focused on the head only). “As is” is a descriptor that I use often in my photoblog, but that doesn’t mean the images weren’t edited — rather it means the JPGs were edited in camera using one of the Fujifilm film simulations (PROVIA / STANDARD).

63 JPGs | Helicon Focus | Rendering Method B

In my limited experience using Helicon Focus, rendering Method C seems to work better than Method B. (For what it’s worth, rendering Method A never produces good results for me.) In this case, I can’t see a clear difference in the quality of the output. Do you think one version looks better than the other?

63 JPGs | Helicon Focus | Rendering Method C

Look closely at the full-size versions of the preceding composite images and I think you will agree with me that the image quality is excellent!

Tech Tips

In a recent blog post, I wrote …

Rik [Littlefield] developed another telecentric lens rig that results in lower magnification (0.8x versus 1.69x) but better image quality. I need to order some inexpensive parts before I can build and test that rig. Source Credit: Experimenting with a telecentric lens rig (plus Post Update).

The last part I needed was delivered a few days ago, and much to my amazement all of the parts fit together! (See parts list, below.)

I used my Apple iPad mini 6 to shoot the following quick-and-dirty photos of the new telecentric lens rig.

Here’s a parts list (shown from left-to-right in the preceding photos).

  • Fujifilm X-T3 (APS-C) mirrorless digital camera [not shown]
  • Fringer EF-FX Pro II
  • [1] Canon EF 100mm f/2.8 Macro lens
  • [2] 67mm to 52mm step-down ring
  • [3] M52-M42 step-down ring
  • [4] Fotasy M42-M42 helicoid [15-26 mm long (11 mm travel).]
  • [5] M42 tube (7 mm long) [WeMacro 42mm tube set: 7, 14, 28 mm long.]
  • [6] 42mm to 52mm step-up ring
  • [7] 52mm-43mm step-down ring
  • [8] Raynox DCR-250 close-up filter (43mm thread)

Notice the focus ring on my Canon Macro lens is set for infinity [highlighted by a green rectangle]. The distance between the front of the Canon lens and front of the Raynox close-up filter is ~54 mm, based upon guidance from Rik Littlefield.

With the Canon Macro lens set for infinity, the parts in front of the Canon lens work together with the lens to make it telecentric. Adding the Fringer adapter has no effect on the telecentricity of the Canon lens — it’s only used to enable my Canon lens to work with the Fujifilm X-T3 camera.

Safe step size

I used Rik Littlefield’s excellent DOF Calculator plus personal guidance from Rik to determine the safe step size to use for focus bracketing with the new telecentric lens rig.

My input is highlighted by a red rectangle; the calculator output is highlighted in green.

Notice I input a 20% step overlap (0.2) to be sure there was no “focus banding.” The calculator suggested a step size of 0.17589 mm. That’s equivalent to 175.89 µm (micrometers).

Since the smallest increment on my NiSi NM-200 manual focus rail is 10 µm, I divided 175.89 by 10 in order to determine the number of increments to turn the larger adjustment knob on the NM-200. The answer is 17.589 increments. For simplicity and safety, I turned the knob 15 increments between shots.

Copyright © 2023 Walter Sanford. All rights reserved.

Experimenting with a telecentric lens rig (plus Post Update)

July 11, 2023

I’ve been experimenting with a telecentric lens rig. My rig is cloned from a similar one created by Rik Littlefield, using gear I already own.

I’m guessing you’re thinking “What is a telecentric lens?” The honest answer is “I don’t know.” I’m not sure I’ll ever understand what telecentric lenses are and how they work. I’m hoping practical experience will result in better understanding of the theoretical.

So why have I written a blog post about a topic I don’t really understand? Good question! The simple answer is because I have learned enough, mostly from Rik Littlefield, to know there are practical advantages to using a telecentric lens for macro photography.

The best advantage of a truly telecentric lens is there should be little or no “focus breathing” as the camera moves closer to/farther from the subject. Essentially that means the apparent size of the subject should remain the same. That should enable better focus stacking because the outline of the subject is constant.

My Rube Goldberg telecentric lens rig

Rik Littlefield’s telecentric lens rig features the same gear as mine (described in the next paragraph) minus the Canon-to-Fujifilm lens adapter because he uses a Canon EOS Rebel T1i DSLR camera body with his rig.

My Rube Goldberg telecentric lens rig is cobbled together using a Raynox DCR-250 close-up filter attached to my Canon EF 100mm macro lens using the plastic clip-on adapter supplied by Raynox. The lens assembly is mounted on my Fujifilm X-T3 APS-C digital camera using a Fringer EF-FX Pro II adapter.

Rik developed another telecentric lens rig that results in lower magnification (0.8x versus 1.69x) but better image quality. I need to order some inexpensive parts before I can build and test that rig.

Testing 1, 2, 3.

The following closely-cropped composite image shows the result of my first test of the telecentric lens rig.

I shot 57 images of a toy plastic lizard using my NiSi NM-200 manual focus rail. I used an aperture of f/8 and a step-size of 100 microns, as recommended by Rik Littlefield.

Helcion Focus Method B was used to focus stack the “as is” JPGs from my camera. The resulting TIF file was cropped using Apple “Preview” — that’s about as quick and dirty as cropping gets!

Post Update

The first time I heard about telecentric lenses is when Allan Walls teased the topic during one of his YouTube live-streams. During a subsequent live-stream, Allan demonstrated how to make a lens telecentric using a rig similar to one that Rik Littlefield created.

Telecentric Lenses – Macro Talk Too – from Allan Walls Photography, June 29, 2023 (1:12:10)

Allan’s YouTube live-streams are one hour in duration, but there’s usually a lot of chit-chat during a typical live-stream that might not interest readers of my blog.

In this case, I recommend that you watch the segment from 11:22 to 30:21. A lot of what I have learned about telecentric lenses from Rik Littlefield and Allan Walls is covered during that part of the video. (If you continue watching the video beyond the 30:21 mark, then you will hear my name mentioned twice.)

Copyright © 2023 Walter Sanford. All rights reserved.

Helicon Focus: Rendering in action (plus Post Update)

June 2, 2023

In my last blog post, I shared a composite image that was created using Helicon Focus to focus stack 99 JPG photos taken automatically using my Fujifilm X-T5 set for AUTO FOCUS BKT.

The following video demonstrates two strengths of Helicon Focus.

  1. It’s relatively simple to use. Creating a focus stacked composite image can be as easy as a two-step process: add source images to Helicon Focus by drag-and-drop; click the “Render” button.
  2. Rendering works quickly. For example, 99 photos focus stacked in ~50 seconds! (~00:08 s to ~00:58 s.)

The main window features two panels: the panel on the left shows the source images as the focus stack is created; the panel on the right shows the final output.

The right sidebar shows a list of filenames for the source images. When a filename in the list is highlighted, the corresponding image is displayed in the left panel of the main window.

Look closely at the final output, shown in the right panel in the main window. Notice the “ghost” artifact that’s visible near the tip of the toy dinosaur’s tail. Otherwise, the composite image looks perfect.

Click here to see a Screen Recording of the Rendering process.

I have no idea what caused the artifact. For whatever reason, some of the composite images I have created using Helicon Focus have one or more artifacts.

In contrast, every time I have used Fujifilm AUTO FOCUS BKT it has worked perfectly. (He said with fingers crossed.)

Related Resources

  • https://youtu.be/jr5SMaO4qWI
  • When dinosaurs attack! – This blog post shows the final image after I used Helicon Focus “Retouching” to fix the “ghost” artifact.
  • Focus bracketing and focus peaking – When I watched the real-time display of Helicon Focus rendering “Method C” for the first time, I was reminded of a blog post featuring two videos I created to demonstrate how focus peaking can show the way focus bracketing works. Those videos aren’t as steady and smooth as I’d like, but hey, not bad for a manual focus rail!

Post Update

When I tested the link to the video I noticed a problem with “flash dropout.” Two small LED panels and two external flash units were used to light the scene. Notice the flash on the right side of the subject didn’t fire in photo DSCF1214.JPG. That flash was a Godox MF12. Up until now, the MF12 flash has never failed to fire. For those who might be wondering, the Lithium Ion battery in the MF12 was fully charged before I started the focus bracket. I’ll watch it more closely to see whether reliability is an issue.

Copyright © 2023 Walter Sanford. All rights reserved.

When dinosaurs attack!

May 30, 2023

Run for your life!

Toy dinosaur.

The preceding composite image was created using Helicon Focus to focus stack 99 JPG photos taken automatically using my Fujifilm X-T5 set for AUTO FOCUS BKT. The composite image was created using unedited JPGs straight out of the camera.

When you use AUTO FOCUS BKT, you select two endpoints for your focus bracket (Point A and Point B) and the camera sets the step size between shots automatically.

If your goal is to create a composite image with the subject entirely in focus, here’s a helpful tip. As you are looking through the camera viewfinder, or in my case looking at the LCD on the back of the camera, it can be difficult to be sure which point on the subject is closest to the front of the lens and which point is farthest.

For example, looking at the composite image shown above, can you be certain one of the toy dinosaur’s legs doesn’t extend in front of it’s nose? I couldn’t. So what should you do before starting the photo shoot?

I think it’s helpful to look at the subject perpendicular to the camera/lens line of sight, as shown below. In this straightforward example the nearest and farthest points on the subject are obvious — Point A is the tip of the dinosaur’s nose and Point B is the tip of it’s tail. This tip should be useful for subjects that are more complex than my toy dinosaur.

Toy dinosaur (side view).

For what it’s worth, the preceding photograph was taken using my Apple iPad mini 2.

Tech Tips

“Rendering” Method C in Helicon Focus worked best for this subject/composition, but it didn’t work perfectly. There was one artifact that doesn’t appear in any of the 99 focus bracketed photos used to create this composite image, so I knew that in-camera focus bracketing was working properly in my Fujifilm X-T5.

I used “Retouching” to fix the artifact. This was the first time I have used the retouching tools in Helicon Focus. I must admit the experience wasn’t as painful as I was led to believe, but it took a little experimentation to figure out the process.

At this point, I feel like I don’t have enough experience to share directions for how I removed the artifact. But I did take notes so I can refine the process and you can be sure I’ll do a follow-up blog post related to retouching as soon as I don’t feel as lost as I did this this time!

Copyright © 2023 Walter Sanford. All rights reserved.

I love it when a plan comes together!

April 21, 2023

Do you remember The A-Team, a classic 1980s TV show? One of Colonel John “Hannibal” Smith’s catch phrases was “I love it when a plan comes together!” So do I.

In my last blog post, I wrote the following …

Look closely and you should notice a few places that appear to be artifacts resulting from the focus stacking process. (Look around the borderline between the toy dinosaur and NSTA plastic ruler.) … I must admit this is cause for concern. Source Credit: More testing, AUTO FOCUS BKT, by Walter Sanford.

Could you tell I was more than a little discouraged by the discovery of artifacts in my focus-stacked composite images? I was. So I devised a plan for isolating the cause of the problem and finding a solution.

The plan

First I looked at the source images for the composite images. I didn’t see the same artifacts in any of the JPG files used to create the focus stacks, so I knew that in-camera focus bracketing was working properly in my Fujifilm X-T5.

Next I re-rendered (is that a word?) the source images using Helicon Focus Method A and Method C. My hypothesis, based upon limited experience and knowledge gained by following the “Focus stacking – Helicon Focus” Facebook group, was that rendering Method C would work without creating artifacts.

Turns out I was right. Look closely at the full-size version of the following focus-stacked composite image and you should see the artifacts are gone. And that’s a good thing, because as far as I can tell using the retouching tools in Helicon Focus means “you’re entering a world of pain.” (Source Credit: John Goodman as Walter Sobchak in “The Big Lebowski.”)

Toy dinosaur focus stack: two flashes; 74 frames; rendering Method C.

Buoyed by my success with re-rendering the source images for the composite image of a toy dinosaur, I used Method C to re-render the source images for the composite image of a toy lizard. Same result: Artifact problem solved!

Toy lizard focus stack: one flash; 96 frames; rendering Method C.

So now both composite images are tack-sharp from front-to-back and artifact-free. Yep, I love it when a plan comes together! And looking at the bigger picture, now I know for sure that Fujifilm in-camera AUTO FOCUS BKT works as I hoped and works well. That’s a win-win!

Why do we focus stack?

The composite image of the toy dinosaur, shown above, was created using 74 unedited JPGs straight out of my Fujifilm X-T5 digital camera. All of the photos were shot using an aperture of f/11.

The following slideshow was created using the first, middle, and last photos in the set (frames 01, 37, and 74). The focus point moves from the tip of the head, to somewhere along the body of the toy dino, and to the tip of its tail. In each of the photos, notice how little of the toy and ruler are acceptably in focus — even at a relatively small aperture of f/11. And that, ladies and gentlemen, is why we focus stack!

This slideshow requires JavaScript.

Related Resources

Copyright © 2023 Walter Sanford. All rights reserved.

AUTO FOCUS BKT (plus Post Update)

April 14, 2023

Let me say at the outset I love my Fujifilm X-T3 digital camera. That being said, I bought the Fujifilm X-T5 almost as soon as it was released.

There are many reasons I decided to buy the Fujifilm X-T5 but the number one reason is the X-T5 features both Auto- and Manual mode focus bracketing while the X-T3 is Manual only.

At some point I’ll revisit MANUAL mode focus bracketing, but this post will focus on AUTO FOCUS BKT. Using AUTO FOCUS BKT, the photographer sets the beginning and ending focus points and the camera selects the step size and number of frames automatically.

Sample output

The following composite image was created using Helicon Focus to focus stack 96 JPG photos taken automatically using my Fujifilm X-T5 set for AUTO FOCUS BKT. The composite image was created using unedited JPGs straight out of the camera.

Toy lizard plus NSTA plastic ruler.

As you can see, both the toy lizard and NSTA plastic ruler are in focus from front-to-back without any focus banding. The process worked surprisingly well and could be a game-changer for creating focus stacks of relatively larger macro subjects.

Step-by-step instructions

The next two images are screenshots from  the online version of the Fujifilm X-T5 Owner’s Manual. From the Table of Contents, click on “Shooting Menus”; from the sub-menu that appears on screen, click on “Shooting Setting (Still Photography).” Click on Drive Setting; navigate to the section entitled “FOCUS BKT SETTING” and look for “AUTO.”

Steps 1-3 …

Steps 4-5 …

Here’s my interpretation of the preceding outtakes from the Fujifilm X-T5 Owner’s Manual. I suggest you follow the set of step-by-step directions that makes more sense to you, although I think they are complementary.

First, a few words of caution about something that can and probably will trip you up the first time you try focus bracketing, using either MANUAL- or AUTO mode. (That’s the voice of experience talking.) You need to make settings in several places including one setting on the camera itself and two MENU settings. All of those settings are highlighted in boldface red text.

  1. Set the “Drive dial” [physical dial located under “Sensitivity dial” (ISO)] for BKT.
  2. Press MENU/OK. [press left trackpad button] Select Drive Setting (camera icon) > [press right trackpad button]
  3. BKT SETTING > [press right trackpad button]
  4. BKT SELECT > [press right trackpad button] FOCUS BKT [press OK]
  5. [bottom trackpad button] Select FOCUS BKT > [press right trackpad button] AUTO > [press right trackpad button] INTERVAL [set for 10 s [press OK]
  6. SET POINT A – Use the “Focus stick (focus lever)” to move the focus point to your desired location. Press the button for back-button focus [AF ON button, by default]. [press OK]
  7. SET POINT B – Relocate the focus point. Press the button for back-button focus [AF ON button, by default]. [DO NOT press OK!]
  8. BACK, END – Press the DISP/BACK button one time until you see the menu screen where you choose either “MANUAL or AUTO.” [This step seems a little counterintuitive to me, but it works.]
  9. Press the “Shutter button.” I recommend a 10 s timer; there is a countdown for the first shot only.

When you are setting focus for Point A and Point B, you can use any method that works for you including simply turning the focus ring on the camera lens. I prefer to use back-button focus. When the camera is set for Manual focus mode (M) the “AF ON” button is used for back-button focus by default. Try it — I think you’ll like it and it just works right out of the box.

I set Point A for the tip of the lizard’s nose and Point B for the tip of its tail.

Tech Tips

X-T5 camera/lens settings: f/11; ISO 200; 1/250 s. White balance set for AUTO WHITE PRIORITY WBW. Single point focus. Number of Focus Points set for 425. “Focus mode selector” set for “M” (Manual focus).

Off-camera lighting:
  • Godox XProF flash trigger
  • Godox MF12: Modeling light = 10/10; flash power ratio = 1/8.

Bear in mind I didn’t really worry about lighting the subjects properly. I chose to use one external flash unit that I knew from experience would work reliably at 1/8 power. I’m pleased to report there weren’t any “dropped frames” due to flash failure.

Interval: 5 s ← Note: The built-in camera timer doesn’t work when using focus bracketing (except for the first photo) so I recommend you increase the  Interval to 10 s in order to give your camera time to settle between shots and plenty of time for your external flash units to power-cycle.

Subject: Toy lizard plus NSTA ruler = 96 frames (selected by camera automatically).

Background/”stage”: White reference card from a Vello White Balance Card Set (Small), and NSTA plastic ruler.

What are the take-aways?

My goal was to test the Fujifilm in-camera photo bracketing process using “AUTO” mode.  Zoom in to look at the full-size image — the detail is impressive! I’d say the test was a complete success. Well, mostly successful. For details, see “More testing…” under Related Resources.

Related Resources

Post Update

Chris Lee, also known as “pal2tech,” released a related YouTube video after I published my blog post: “Why I LOVE This Fujifim Lens! (30mm Macro),” by pal2tech (11:26). Although the main theme of the video is a detailed review of the macro lens, there is an embedded segment related to how to use AUTO FOCUS BKT and Helicon Focus beginning at the 05:05 minute mark and ending at ~07:47: “How To Focus Stack With Fujifilm Macro Lens.” Well done, Chris!

It’s worth noting I disagree with Chris’s recommendation of the Fujifilm XF30mm F2.8 R LM WR Macro lens. Regular readers of my blog know I’m all about macro photography and don’t need much of an excuse to buy more gear. I considered this lens carefully when it was announced and rejected it as a bad fit for my needs.

Chris has valid reasons for liking the lens and I have valid reasons for disliking it — we just disagree, that’s all. For example, Chris raves about how close you can get to the subject with this lens. Sounds good, but the reality is a small working distance makes it much more challenging to light the subject properly. And Chris readily concedes the lens isn’t perfect, optically speaking.

Bottom line: I strongly recommend the tutorial segment of Chris’s video while cautioning my readers to carefully consider whether this lens would be a good fit for your macro photography needs.

Copyright © 2023 Walter Sanford. All rights reserved.

Making progress (on a steep learning curve)

March 17, 2023

OK, let me say right at the outset that using a manual focus rail like my new-ish NiSi NM-200 to create a 328-photo focus stack is insane! So I regrouped, made a new plan, and conducted some tests.

I discovered, albeit too late, that I needed to shoot a lot of  photos for my last focus stack because I chose to use an aperture of f/8 and the “safe step size” for f/8 (at 1x magnification) is 40 µm (micrometers, or microns) — a relatively small step size.

In contrast, at 1x magnification the safe step size for f/11 is 800 µm — during limited testing that seems to be the sweet spot for creating focus stacks that look fairly good using fewer photos.

Canon EOD 5D Mark II DSLR camera plus Canon EF 100mm macro lens (1x, f/11)

The following composite image was created from 20 photos.

The background is the non-reflective side of a piece of black plastic. It’s textured surface appears to be a bad fit for macro photography — notice lots of little white specks on the background. Not good.

f/11 | 1/200 s | ISO 100 | Manual WB (Flash)

But wait, there’s one more thing. Did you notice the copper penny hiding underneath the quarter? Well, it was supposed to be hiding. I borrowed the idea from another photographer whose name I can’t remember. The point is to create some visual relief for the coin in the photo. The plan might have turned out OK if I’d noticed the misalignment of the penny before I did the focus bracketing.

Fujifilm X-T5 mirrorless digital camera plus Fujinon 80mm macro lens (1x, f/11)

The following composite image was created from 26 photos.

For the background, I used the white reference card from a Vello White Balance Card Set (Small). I set the white balance for AUTO WHITE PRIORITY WBW — a new setting (at least new to me) that’s supposed to result in whiter whites.

f/11 | 1/250 s | ISO 125 | WBW

The subject is in focus from back-to-front, and I like the white background. I think this is the best composite image I’ve created so far, but as always, you be the judge.

Fujifilm X-T5 mirrorless digital camera plus Fujinon 80mm macro lens (1x, f/11)

The following composite image was created from 21 photos.

For the background, I used the black reference card from a Vello White Balance Card Set (Small). I think it looks better than the textured black plastic background in the first photo, although I think the white background looks best.

f/11 | 1/250 s | ISO 125 | WBW

Pixel-peepers will notice the far end of the nickel isn’t as sharp as the rest of the coin. That’s because a man-caused disaster forced me to leave out the first two photos in the set. I hope the man responsible for this sloppy work will be held accountable for his actions!

Tech Tips

I think it’s worth noting that all three composite images were created using unedited JPGs straight out of the camera. All of the composite images could have been improved by making a few edits to the RAW files such as adjusting exposure, increasing contrast, and adding a little sharpening, to name a few.

In these test cases, I was looking for focus banding caused by using a step size that’s too big and glitches caused by Helicon Focus, the focus stacking software I used. As far as I can see, no problems.

My NiSi NM-200 is mounted on a Manfrotto 405 3-Way, Geared Pan-and-Tilt Head. The camera line of sight was inclined at a 45° angle relative to the staging surface. That’s less important in this case and more important for an upcoming review of the NiSi NM-200 focus rail.

Both cameras were set for manual exposure. Both lenses were set for manual focus; the combination of manual focus and back-button [auto]focus gives me the best of both worlds.

I use single point focus nearly all the time. I moved the focus point to the farthest point of each subject, then used back-button focus to autofocus on the subject and shoot a photo. Without changing focus from the first photo, I used the focus rail to move across the subject from back-to-front in 800 µm increments (eight numbered increments on the NiSi larger adjustment knob), taking a photo at each step.

More light is required for proper exposure at f/11 than f/8. I used one Sunpak LED-160, one Godox TT685C external flash unit (plus Altura flash modifier), and one Godox MF-12 external flash to light the first subject (Virginia quarter). Two Sunpak-160s and two Godox TT685C external flash units (using Altura and Lastolite flash modifiers) were used to light the last two subjects (quarter and nickel coins).

Related Resources

Copyright © 2023 Walter Sanford. All rights reserved.

Comedy of errors

March 14, 2023

My first big focus stack turned out to be a comedy of errors. Lots of little things, all of them avoidable, but the one that broke the stack was when the camera battery died approximately two-thirds of the way through the project.

My new Fujifilm X-T5 has a much larger battery than my Fujifilm X-T3 so I never imagined it wouldn’t last long enough to create the stack.

I might have been able to salvage the stack by changing the battery without removing the camera from the focus rail, but the Manfrotto quick release plate partially blocked the battery door. Doh!

l use Arca Swiss L-brackets for all of my cameras. Good L-brackets are designed so the bracket doesn’t block any camera doors or ports. But I don’t have one for the X-T5 because it’s new enough that the selection of compatible L-brackets is poor.

I have two ways to provide continuous power for the X-T5 but I couldn’t use them because the battery door was partially blocked. Double doh!

Making lemonade from lemons

Long story short I used Helicon Focus to stack all the photos up until the power failure and the results look fairly good, as shown below. Oh what might have been. Triple doh!

ISO 400 | 80mm | 0 ev | f/8 | 1/250 s

The preceding composite image was created from 192 of 328 photos. I used a safe step size of 50 µm (microns) between photos. Each JPG photo is ~13 MB, 7728 × 5152 pixels.

The coin is acceptably in focus from the top of the coin to a point about two-thirds of the way toward the bottom. Zoom in on the horse’s head and you should notice sharp focus is lost beginning below its eye.

The amount of detail in the composite image is astounding, as shown in the close-up of the upper-right quadrant.

Close-up, upper-right quadrant.

Related Resource: Post update on 11 April 2023.

Copyright © 2023 Walter Sanford. All rights reserved.

Post update: What is it?

February 28, 2023

The mystery object shown in my last blog post is a macro composite image of the right eye of Benjamin Franklin, as he appears on a $100 bill. The $100 bill is the largest denomination Federal Reserve note currently issued for public circulation.

Image Credit: Wikimedia Commons.

Tech Tips

2.5x magification | aperture f/4 | shutter speed 1/250 s | ISO 160

The preceding image is a focus stacked composite of 77 JPG photos taken with my Fujifilm X-T3 digital camera plus a Laowa 25mm Ultra Macro lens. The lens was set for 2.5x magnification and an aperture of f/4, the “sweet spot” for this lens.

The camera was mounted on my NiSi NM-200 manual focus rail. A safe step size of 50 microns was used in order to avoid focus banding, as determined by using Zerene Stacker DOF Calculator.

For better composition of the final composite image, I created the stack by focusing past the farthest focus point and moving the rail backward to slightly beyond the closest focus point. (Remember, the subject looks bigger at the farthest focus point than the closest. This almost certainly means it will be necessary to crop the final image if you shoot front-to-back. Going back-to-front helps to avoid this problem.)

The carriage of the focus rail traveled a total distance of 3.85 mm.

77 steps/1 x 50 microns/step = 3,850 microns

3,850 microns/1 x 1 mm/1,000 microns = 3.85 mm

77 steps is probably more than necessary but I wanted to be sure the entire image is acceptably in focus.

Helicon Focus was used to create the focus stack. The final rendering is saved as a TIF file, by default. I converted the TIF to JPG for posting in my photoblog. The final output, shown above, is unedited otherwise.

Sidebar

A micrometer (also known as a micron) equals 0.001 of a millimeter, or 1/1,000 of a millimeter. In other words, there are 1,000 micrometers in one millimeter. The symbol for micrometer is µm.

Related Resources

Copyright © 2023 Walter Sanford. All rights reserved.