Posts Tagged ‘Panasonic “Post Focus”’

Depth of field

November 11, 2022

Once a teacher, always a teacher. I guess that’s the reason I like to create and share blog posts that relate to things I’ve learned about photography. Such as depth of field.

Depth of field, more specifically shallow depth of field, is the reason many macro photographers like to do focus bracketing and focus stacking.

In order to demonstrate shallow depth of field, I arranged the same three studio “models” (used in my last blog post) in a way that would be impossible for the camera to capture all three subjects in focus. For what it’s worth, the distance between the closest and farthest model was approximately six inches.

To add to the challenge, I changed the aperture from f/7.1 to f/5.6 — that’s closer to the “sweet spot” of f/4 for the lens in my Panasonic Lumix DMC-FZ300, but the depth of field at f/5.6 is shallower than f/7.1. How shallow is it? (Queue Johnny Carson.) For the answer, I turned to my favorite online “Depth of Field Calculator.”

Notice I selected “Panasonic Lumix DMC-FZ150” as the camera. That’s because the FZ300 isn’t on the long list of cameras supported by the calculator. No problem. I own both the FZ150 and FZ300 and I can tell you they are virtually identical in every significant way.

My camera was mounted on a tripod so that the front of the lens was approximately five inches from the closest subject. The focal length (mm) of the lens was derived from the EXIF info for one of the three photos shown below.

Look at the calculator output, highlighted by the red rectangle in the preceding screen capture. Notice the total depth of field is 0.24 inches — that’s only around 1/4 inch! There’s NO WAY all three subjects can be acceptably in focus using my FZ300 and the camera settings I selected.

Post Focus

I used Panasonic “Post Focus” to capture the scene. This time, I used “Post Focus” to select different focus points after the shot was taken. During playback, I selected three focus points, one at a time, and saved the following JPG files.

For the first photo, I selected a focus point on the toy monkey. Notice the orange dinosaur in the background is clearly out of focus. Wait, did I really just say that? Yeah, go with it — you know what I mean.

Focus point on nearest subject.

For the next photo, I selected a focus point on the green dinosaur. I don’t know whether I’d call the other two subjects “acceptably in focus” but I know they aren’t tack sharp.

Focus point on middle subject.

For the last photo, I selected a focus point on the orange dinosaur. Notice the toy monkey in the foreground is out of focus.

Focus point on farthest subject.

So there it is — if you would like all three subjects to be in focus then focus bracketing / focus stacking is the only way to go.

My last blog post, entitled “Focus bracketing using Panasonic “Post Focus,” explains how Panasonic “Post Focus” can be used with Adobe Photoshop to do focus bracketing and focus stacking.

Related Resources

Copyright © 2022 Walter Sanford. All rights reserved.

Focus bracketing using Panasonic “Post Focus”

November 8, 2022

It’s been quite a while since I experimented with focus bracketing using Panasonic “Post Focus.”

“Post Focus” is a feature available on select Panasonic cameras (such as my Panasonic Lumix DMC-FZ300 superzoom bridge camera) that enables the photographer to select different focus points after a shot is taken. That’s cool! Turns out “Post Focus” can be used to do focus bracketing / focus stacking too, and in my opinion that’s way cool!

When “Post Focus” is turned on, the camera actually records a single frame of 4K video at 30 fps (MP4 in 4:3 aspect ratio) as it cycles through the 49 focus points from front-to-back.

Since “Post Focus” records short video clips, continuous light sources such as my Sunpak LED-160 must be used to enhance/supplement ambient light.

I set up two scenes using the same studio “models”: the first was shot in landscape mode; the second in portrait mode.

Landscape mode.

As you can see, the lighting doesn’t look good. I usually use external flash units rather than continuous light sources. I need to work on that.

I didn’t edit either of the final composite images because my goal was to test to see whether all three subjects are in focus. They are.

Portrait mode.

Tech Tips

I programmed the Fn4 button to turn “Post Focus” on/off. [Editor’s Note: The default setting for Fn4 is LVF. LVF enables the user to switch between the monitor and viewfinder.]

The following camera settings were used: focal length = 4.5mm (28mm, 35mm equivalent); aperture = f/7.1; shutter speed = 1/80 s; ISO = 400. AF mode set for 49 points.

In order to create the preceding focus stacks, I opened two MP4 files in Adobe Photoshop. Next I exported video frames as individual files that can be imported into Photoshop for focus stacking. I prefer TIFF files rather than JPGs. Then the TIFF files were imported into Photoshop for focus stacking.

That’s an oversimplification of the process. Never fear — Photo Joseph does a good job of explaining the process in detail in the following YouTube video.

Related Resource: 4K Focus Stacking with Panasonic LUMIX Cameras – Presented by LUMIX Luminary Photo Joseph (7:34).

“Post Focus” image: toy dinosaur

February 8, 2019

A toy dinosaur was “photographed” at BoG Photo Studio using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.”

The camera was set for ISO 100 and Aperture Priority at f/2.8. Two Sunpak LED-160 Video Lights plus a Nissin i40 external flash unit (set for video light) were used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the following focus-stacked composite image.

A plastic toy dinosaur.

Noise (graininess) has been a problem in some previous test shots using “Post Focus,” due to low light (underexposure). I changed the ISO from AUTO to 100 for this test, opened the aperture all the way to f/2.8, and added a third LED light source.

This is the first time I tested “Post Focus” and felt like the camera had a mind of its own! Nonetheless, the final output turned out OK. Further research and experimentation is required in order to understand what happened and why.

Copyright © 2019 Walter Sanford. All rights reserved.

“Post Focus” images: Shadow Darner dragonfly

January 30, 2019

Bob Perkins collected and reared a Shadow Darner dragonfly (Aeshna umbrosa) larva/nymph. This blog post features two focus-stacked composite images of a beautifully preserved specimen of the adult that emerged from the larva.

Each composite image was created from 30 TIF files extracted from a one-second MP4 video of the subject, “photographed” using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.”

This individual is a male, as indicated by his terminal appendages and “indented” hind wings (shown above). All male dragonflies have three terminal appendages, collectively called “claspers”: the two cerci are missing (they broke off the terminal end of the abdomen during shipping); the epiproct is intact.

Shadow Darner (Aeshna umbrosa) | dorsal-lateral view

Takeaways

Perhaps the biggest takeaway from on-going experimentation with Panasonic “Post Focus” is that the process continues to impress — it works quickly (typically one second or so) and works well, using lightweight, inexpensive equipment for making composite images of acceptable quality.

What’s not to like? The obvious answer: The image quality isn’t as high as comparable images created using HEAVY and EXPENSIVE camera gear in the controlled environment of a photo studio. On the other hand, I know from experience I’m unlikely to lug all of that gear into the field. I call it a BIG WIN to have found a relatively lightweight, inexpensive camera kit that does essentially the same job almost as well!

The next test: Use adult dragonflies in the wild as the subject. Regrettably, that will have to wait until the first odonates begin emerging during early spring.

Related Resources

Tech Tips

The following equipment was used to shoot the “photos” for creation of the composite images, shown above: Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus“; and two Sunpak LED-160 Video Lights.

Adobe Photoshop CC 2017 was used to create the preceding focus-stacked composite images, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

More testing: Panasonic “Post Focus”

January 28, 2019

A toy dragonfly was “photographed” at BoG Photo Studio using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.” Two Sunpak LED-160 Video Lights were used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the following focus-stacked composite image.

A plastic toy dragonfly.

The test shots featured in my last blog post, and this one, were taken in order to establish the proof of concept that Panasonic “Post Focus” can be used to quickly (well, everything is relative) create high quality focus-stacked composite images. After limited testing, I can say the process works fairly well.

The next test: Use a preserved specimen of a real adult dragonfly as the subject. Please stay tuned for my next blog post.

Copyright © 2019 Walter Sanford. All rights reserved.

Testing: Panasonic “Post Focus”

January 25, 2019

My new Panasonic Lumix DMC-FZ300 features some significant upgrades over my DMC-FZ150 such as a touch-screen LCD, built-in WiFi (enabling remote control of the camera using the “Panasonic Image App“), 49 focus points, and 4K video, to name a few. Perhaps the most intriguing new feature is what Panasonic calls “Post Focus.”

“Post Focus” can be used to change the focus point after a photograph is taken, in camera. OK, that’s astounding! But wait, there’s more.

With “Post Focus” enabled, the camera is used in the same way as when you’re shooting still photos. In reality, the camera records a small movie clip in 4K video at 30 fps (4:3 aspect ratio) every time you press the shutter button.

The 4K movie recording function is used to record roughly one second of MP4 video at 30 frames/second. During this recording, the camera’s autofocusing system scans the lens around the subject, moving from the foreground to the background to cover the entire scene. … It’s like a sophisticated form of focus bracketing and produces a movie clip containing about 30 frames. Source Credit: How the Panasonic Post Focus function works.

One reviewer of photography gear opined the process is too slow to be useful in real-world situations; in contrast, my first impression is the process works surprisingly quickly.

An MP4 file can be opened in Adobe Photoshop in order to export individual frames from the 4K video clip; the files can be saved in either JPG or TIF format. In turn those files can be imported into Photoshop to create a focus-stacked composite image, such as the one shown below.

A plastic toy Pterodactyl, 6.5″ in width.

A toy Pterodactyl was “photographed” at BoG Photo Studio using Panasonic “Post Focus.” One Sunpak LED-160 Video Light was used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the preceding focus-stacked composite image.

I think Panasonic “Post Focus” shows great potential for enabling the production of high quality focus-stacked composite images when photowalking, without carrying a lot of photography gear into the field.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.


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