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This ATEM (mini) Tips” series of short video tutorials for your Blackmagic ATEM hardware includes tips for all users, from beginner to advanced. Scroll down to see more in the series!

This is a collection of all PhotoJoseph LIVE shows, from the PhotoJoseph YouTube channel. Additional episodes are listed below!

DFD (Depth from Defocus) on GH5 Explained

Photo Moment - March 06, 2017

Ever wondered what DFD (Depth from Defocus) technology is and how it works on the new LUMIX GH5? A comment was left on one of PhotoJoseph's videos about Depth From Defocus, but it was based on inaccuracies. PhotoJoseph is here to set it straight and educate.

 

PRODUCTS MENTIONED IN TODAY'S PHOTO MOMENT (MANY ARE AFFILIATE LINKS):
Panasonic LUMIX GH5 [B&H - https://bhpho.to/2kQ9LT3 ] [Amazon - http://amzn.to/2lE4X1U ] [Adorama - http://jal.bz/2lNYpQv ]
OMOTON Desktop Cell Phone Stand: [Amazon -http://amzn.to/2mbJyNQ]

VIDEOS MENTIONED IN TODAY'S PHOTO MOMENT:
GH5 Autofocus System Explained!: https://youtu.be/6PyqWrztPkc
GH5 Sample Content by PhotoJoseph (Playlist): https://www.youtube.com/watch?v=GTMr5C50Cck&list=PLRe8DcOhgslqq0vneERdGG…

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Can't decide between the Panasonic 35-100mm f/2.8 and the Olympus 40-150mm f/2.8 PRO for my GH5. I'm leaning towards the Oly so that when auto-focus fails, I have a linear focus ring that works like a real manual focus ring. Is the DFD really big of a deal that I should buy the Panasonic instead? Looking to use the lens for AF-C or AFS, focus tracking mode. This is for video, not stills.
I'm buying particularly for auto-focus. For strictly manual focusing, I have other lenses for that. Thanks in advance. God bless.
Yeah the AF is not as good as Canon’s sadly. Other benefits to the Panasonic.
@@photojoseph thanks for your reply. Sadly M43 is not as popular here in Manila as Canon EF lenses so there's none for rent. But i managed to test the Panasonic in a store yesterday (the only one that has Panasonics in stock) and AF is good, but not as good as my old Canon 70D's dual pixel. As for the Olympus, it's even more difficult to find.
AF isn’t going to be stellar for video although it’s gotten a lot better with all the updates. The Panasonic should definitely be better for AF. That linear MF sounds nice though (I’ve never shot with the Oly). But can you rent both and try them out?
Thanks as always for this Joseph. Question for you - What Depth of Field (DOF) iOS app would you recommend for Panasonic GH5 users?
@@photojoseph Yes a DOF calculator. :) Thanks - I have also seen a ton but didn't know if you knew of one you preferred as some of them seem to be specific to model of camera. Thanks again!
Do you mean a depth of field calculator? I have PhotoPills which has that feature… probably the only app I have that does it, but if you search that on the App Store you’ll find a ton.
Hi Joseph,
Thanks for the note about DFD, was really informative.

I could use your help with something. I'm an amateur photographer trying to get more into travel photography and videography, but mainly videos. I've been using a Fuji X10 for some time now and would like to upgrade to something more powerful. I also think of it as a long-term investment and would like to get a great, slightly more expensive camera over a good, but more affordable one. I'm also a fan of bokeh when it comes to photos and thus thought it'd be a good idea to upgrade to a full-frame camera.

I was thinking of buying the A73 and will have saved enough in 2 months to do so. However, since the announcement of S1, I've been kinda torn. Even though there haven't been many details about the S1, what's known so far is really exciting. (Even with the full-frame vs cropped sensor 4k confusion).

I realize that your opinions will, of course, be biased towards Panasonic, but I still want to ask your opinion about this. Is it a good idea to buy the A73 in 2 months or wait for another 3 months for the S1 to launch? (I'm looking at the S1 with the hope that it'll be priced under $3k. If it's anything above it, I'll have to go for the A73). What do you think?
I looked into the G9. Even though it's a 'Photo centric' camera, it's got some pretty good video features as well. But I was looking into some quality lenses like you suggested and this was the fastest Panasonic lens I could find: https://www.bhphotovideo.com/c/product/1023336-REG/panasonic_leica_dg_nocticron_42_5mm.html. It stands at f1.2, which comes to f2.4 in full frame terms. But if I'm looking at full frame Sony E alternatives, there's the https://www.bhphotovideo.com/c/product/1393494-REG/sigma_85mm_f_1_4_dg_hsm.html, which is much faster. Please correct me if I'm wrong, but it still seems like the full frame has the faster lenses when we equalize the aperture as well.
I haven't given much thought to G9 before. I will look into it. Thank you.
G9. It’s all you’ll need. Spend the savings on good lenses.
Hi,
Thanks for the reply. The bokeh is just one of the reasons. It sure is a pretty good reason for me (so much so that I was thinking of getting a Sigma 85mm f/1.4 with the Sony A73 :)).

But I'm also thinking of it for other reasons. My cases involve both shooting outdoors in the morning and then cities at night. So I think it'd be good to have a better dynamic range when outdoors and also a lower noise in low light situations. I can see myself working in low light situations a lot and I think I'd want the camera to be able to better handle it.

But like I said, I'm still an amateur and I'm not sure if I should be spending as much as I'm on a powerful camera yet.
I think it’s worth waiting. However I also think if the only reason you’re going full frame is for better bokeh, you can buy a micro four thirds camera and lenses like the Nocticron or 15mm Leica or even third party lenses as fast as 0.95 and get the bokeh you seek. No working pro would be happy without bokeh, and lots of us use MFT. Just watch some of my lens-specific videos and you’ll see plenty of bokehlicious photos.
Should DFD stop me from buying an Olympus 12-40mm f2.8 Pro over the Panasonic 12-35mm f2.8?
@Jose Allan we have the Olympus Pro lenses ranging from their 7-14 to their 40-150 f2.8. We use these lenses exclusively with our GH4 and GH5. We can definitely tell you that the DFD autofocusing system is lighting fast for stills (photo) however we cannot comment whether the DFD is useful for video as we don't have a Panasonic lens to compare it with. We hope this helps.
I have no experience with that lens, and in general Panasonic lenses will be most compatible, but an Olympus lens will certainly work.
I have been enjoying watching your shows on replay and hope you are still looking at comments on older videos. These quiestions I am sure you will need to ask someone at Panasonic about and they may not be able to answer yet but it would be good to know. I am almost exclusivly just a stills shooter and use both a G7 and a few different Nikon camera and while I like many of the features in the GH5 I am not sure it has the extra value to me at this stage to buy one over say a G85. While you have been talking about the DFD in this video it got me thinking about a few questions below.

Is it at all pssoble for Panasonic to impove the focusing systems on current modles via a firmware update? (could they add even some basic vector tracking) I know the main improvement is the higher refresh rate.
On a related note do you think they could add at least some more control over how the AF works in curren models?
Will newer non GH models be released with the same level of AF systems? -It would be a shame for us stills shooters to be forced to buy the top of the line model just to get better AF.
Can't they just set a protocol for profiling lenses and have at least the Olympus lenses supported too? The idea of M43 is that it's an open system, so why just try to "close" it up like Canon or Nikon does?
Because Olympus & Panasonic already work together on the M43 system, so why not? I can understand that not all lenses can be supported
Because there are a LOT of lenses out there. If Olympus too, why not X Y and Z? It comes down to resources. It's FAR from a closed system; you just have a slight advantage to using Panasonic glass. I don't think that's a bad thing and any manufacturer of any product in the world will always tell you that you should be using their accessories over third party ones. The other lenses are supported. They just don't get DFD autofocus.


Does Olympus profile Panasonic's lenses?
Love these live bits.. just wish you wouldnt talk so damned slow....=p
"Coffee is the lifeblood of America" ~Will Ferrel "Kicking and Screaming"
I'll drink more coffee ;-)
Do you think that Panasonic will consider adding the vector tracking algorithms to cameras like the G85 or GX85 through firmware updates? Or do they require additional processing power or image processor features that are only present in the GH5?
+J. W. Green Yeah that's not something that can be added. It requires the processor in the GH5.
Joseph help!!!! I want a studio strobe for my lumix setup. Any ideas? Thanks
+Hobby Rx If you want TTL you're out of luck, sadly. If you're good with manual (and honestly I've never had TTL studio strobes for any camera), then you can use anything you like. My preference is Profoto but they all work.
question about manually setting the lens focal length for using the IBIS with adapted lenses: can you assign a custom function button to change the focal length of the lens? this would be useful for adapting zoom lenses.
+Sean Minor Probably to bring up the controller (slider) to choose focal length but not to preset various lengths. Can't verify (don't have a GH5 now) but I'd be surprised if that was in there.
So the Panasonic Leica 12-60 is not as good at focussing as the 12-35 2.8??? Did he mean to put it that way? Did he actually mean "non-panasonic and non-panasonic-leica lenses may not perform as well as our lenses."??
Yes, I presume it would hold to y=0.025x +2.5. At 35mm that means just a tad over half a stop. When I need a walk-around lens it's usually with adequate stage lighting or outside daytime conditions. I never used the 12-35 for low light situations, always swapping out to a prime.
+orange42 Just be aware the 12-60 is f/4 at the long end, while the 12-35 is f/2.8 throughout. That said I kinda fell in love with the 12-60. It's a great lens.
Whew! Thanks for that! Just his wording got me confused. Swapping out the 12-35 with the 12-60 to have the longer reach for walk around photos.
+orange42 Panasonic Leica are Panasonic lenses, and the best of the collection. So they will focus as well other Panasonic (Leica or not) lenses.
I'm new to this channel. Did Joseph say why he gets to keep a GH5 for only a short period of time, and then has to give it up, but later on gets another one?
+Cactus Tweeter Welcome to the channel! I'm a LUMIX Luminary (like the Sony Artisans, or Canon Explorers of Light). There are very few units in the country now and we have to play nice and share them :-)
https://goo.gl/JSDBGD Panasonic GH4 A completely new AF approach - I think all DFD info are included here. It's all about lens data integration. So all non-Panasonic lenses are not applied to the Panasonic DFD (Depth from Defocus) technology, and the "Metabone-Non-Pan Lens-Conection" cannot be benefited from this technology.
DFD in GH4 is the same techonology, except that GH5 has higher "sampling rate" during 60fps video shooting in 4K. For still photos, DFD samples at higher rate, say 120fps than shooting video. The only way to be benefited from DFD during video shooting is to shoot in higher frame rates. https://goo.gl/4wJqrk Panasonic GH5 vs GH4 | Auto Focus comparison [4K] - Face/Eye Detection AF
Panasonic have really done their homework. Big things happen April. The Leica 12-60mm F2.8-F4 now in my kit. Thanks.
Joseph, can u talk about or get an answer about how to synch 2 or more gh5s timecode thru the bluetooth
You can sync as many cameras as needed to time-of-day by Bluetooth from your phone which has arguably the most accurate clock available to you, and will therefore sync all the cameras together. You can NOT do timecode jam sync however. This feature was only available on the GH4 with the YAGH which is not being updated for the GH5. Turns out no one bought the damn thing.
Thanks for clarifying this. From what you have said, the GH5 auto focus technology seems like a great auto focus system and I have no idea why that person thought the DFD used the poorer quality of the lens to get focus, which really didn't make sense to me at all. Since non Panasonic/Leica lenses won't get the DFD, it will be interesting to see how well those lenses focus as I am getting an Olympus 60mm Macro lens since its the longest MFT macro lens there is currently and I need the extra length and would be interested to know how it would focus, but it should auto focus well, even without DFD.
+Dave's Nature Productions UHS-II cards are what you want, especially for shooting 400mbit. Standard UHS-I cards work fine as the camera ships. That's all I have currently!
Thanks. I thought I read (or saw on a video about it) that only Panasonic lenses would get DFD, so would be worth finding out. Do you know what memory cards would be good to use with the GH5? I was thinking of getting a Lexar 256GB Professional 1000x SD (SDXC) Card UHS-II U3 - 150MB/s if that would work with 4K 10bit 4:2:2 or would I need a different card?
I think they still get DFD focusing, but don't get it as fast because the lenses aren't profiled. Although that's worth clarifying, so I will!
Hi Joseph. If at all, if you could find out if the Metabones Speedbooster Ultra 0.71x will be compatible with the GH5, that would great? Thanks for the show. :-)
+Fotodust Pictures Working on it!
I just wanted to use this comments as a forum, if you like towards the discussion of the Speedbooster and 18 - 35mm Sigma combo - everyone seems to be obsessed with it and I can understand the huge appeal of the F1.2 apeture, specifically on the GH4 where high ISO performance was poor. I'd love to get your opinion on this Joseph. To me spending £1200 here in the UK one one lens (granted it covers 2 key prime focal points) seems absurd. By going mirrorless one of the advantages is size, and with so much small and fantastic M4/3 glass nowadays you really can keep the camera small and compact without breaking the bank. Plus with the inclusion of OIS on many Lumix lenses the dual IS looks like a fantastic bet. I'd love to hear the opinions of others on this, am I missing something key?
I was wondering this myself. Its not just the F1.2 aperture people use that combo for, its using a speedbooster can give you less crop and very similar crop factor to using an ASP-C sensor camera which many wanted as they didn't like the 2.3x crop on the GH4 or x2 crop of MFT and wanted a wider FOV. The only time I'd see myself using a Speedbooster (or adapter in general) is if I wanted a lens that there wasn't an equivalent MFT version like a longer than 120mm equivalent focal length macro lens (60mm being the longest on MFT) or a telephoto lens like the Tamron 150-600mm which has a longer zoom than the Leica 100-400mm etc...
+James Cousins I haven't used the combo and perhaps it is the best thing ever, but I can't say. The weight and size advantage of MFT is I think not the deciding factor for a lot of people who are super into using these larger lens combos. Maybe I'm wrong but I think they love the cameras for different reasons (cost is a big factor)
Where do people get this nonsense? I mean, there are plenty of tests out there to show how good some lenses are, so based on what DFD could possibly be based on that? More importantly, which sane company would base their tech on crappy anything? It doesn't make any sense. How is that more plausible than the standard explanation of studying the depth characteristics of a lens? I don't understand.
Who cares about Depth when there is no depth on a FLAT EARTH!!
+Joseph Linaschke +The SUBVERSIVE I was unaware of this conspiracy until recently, so figured it was best to ask Panasonic, via Joseph (thanks guys).

Best I can track as the original source was a comment that Dave Etchells at Imaging Resource made in their 2013/14 interview with Panasonic about the GH4, which was added to the article the interview was in, but clearly not specifically discussed with Panasonic at the time.

The article was published at http://www.imaging-resource.com/news/2014/06/05/panasonic-executive-interview-part-i-why-no-long-teles-and-depth-from-defoc

and the exact quote was:

"They didn't tell me this, but I'm guessing that DxO's infinite depth of field technology is based in part on using longitudinal chromatic aberration to determine how much de-blurring is applied to different parts of the image. They were aiming that technology at smartphone makers. What they did tell me was that if you made a lens with the right kind of distortion, it made it easier for the algorithm to figure out how to process it."

Even without knowing the exact details, this conspiracy approach would not work from a business perspective. Produce crappy lenses so DFD will work? What happens if Panasonic one day produce a great lens, would they then scrap DFD? Or be tied into producing crappy lenses forever?

Frankly, I was appalled that people could believe this crap, let along abuse others for not believing it also!
+theSUBVERSIVE Some one heard it and wanted confirmation 🤔 But I'm happy to have the opportunity to discuss what DFD is.
I’m re-posting my question from the live-show here, to see if anyone else knows how the GH5 utilizes ETC (Extended/Electronic Tele Converter – cropping on the sensor, for pixel by pixel mapping, in video).

I’ve read somewhere that ETC works less than desirable on the GH5 (don't remember exactly what kind of limitations being mentioned). Does anybody know if this is so, and why, if so, that is?

ETC could be somewhat of a free lunch to obtain longer reach (more tele) in video, as it kind of is on my GH2 (if one looks away from the heavier high-ISO-noise). As I am now moving from my beloved GH2 to my now preordered, and much anticipated, GH5 (a very overdue upgrade) I’d really like to continue using this feature, both in 4K and full HD. 4K ETC would also make possible the use of some 16mm lenses, as well as the SpeedBooster XL 0.64x with APS-C lenses.

So any information on how the ETC behaves on GH5 would be much appreciated!

This question might seem very off topic and misplaced, but as I've seen lots of other questions being answered in great detail in this channel I jumped to it.
thank you, very informative :)
I wonder how the new focus on the gh5 is going to work with adapted lenses like the 18-35mm f1.8 with the metabones speedbooster! I hope we get some improvements there...
+kccvaa Hm, someone else reported that they worked fine. I'm trying to get some support from Metabones on this.
If I understand DFD correctly, what the camera's doing is what I was taught when learning photography back before 35mm film disappeared; [final] focus on the subject requires finding/focusing on the subject then refining the focus back and forth until I see that the subject is as sharp as possible?
No; the focus doesn't go back and forth. That'd take too long and you'd see that in video. DFD is calculating differences between two out of focus images (which it presumably grabs as it moves focus) and jumps to that point.
Thanks Joseph, another informative video!
On the subject of how the f-stop changes with zoom on the new 12-60, I saw this in the GH5 Facebook group: "Here is the answer to all asking about the aperture of the new 12-60: The aperture is pretty linear along the range, it starts off pretty straight away to 2.9 and by 18mm it's f/3.2, 25mm f/3.5, 40-50mm f/3.9 and the of course f/4.0." (Posted on FB by Tomás Cruz.)
If it's linear (and I don't see why it wouldn't be) it would be y=0.025x +2.5 where y is the minimum aperture and x is the focal length.
Sweet thanks. I'll check it when I have one again too.
DFD, Vector focusing, etc, not only rely on high quality designs but also on high consistency in manufacture. You cannot spec your algorithms more tightly than your QC/QA. It would be great if Panasonic would profile all m43 lenses, but that may involve testing hundreds of each lens.
Ah, great observation!
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