FAQ Sharing lenses between FS7 and GH5: seeking advise

[M. Gilden]

Thanks M. - your post has been the sort of answer I was hoping for, with lots of ad rem rather than ad personam arguments

I aim to please.

However, I cannot agree with your arguments about 10-bit not being of real importance for somebody serious about grading. I did try to color match my FS7 with A7Sii and A7Rii sample clips (straight from camera), and my impressions were not optimistic at all for 2 reasons:

Stop right there- straight from camera you're only getting 4:2:0. Forgetting the bits used to record color data, there's an actual lack of resolution in color channels that will very much show up when heavily grading. That's why I mentioned using the HDMI out to record 4:2:2. I have a couple of Atomos recorders I use with my cameras, and I can tell you the externally recorded footage is night and day easier to grade. The codec is much better, and there is more color information. Yes, it isn't 10-bit, but as I said before if you take a 4k image and are delivering in 1080, a good downsample algorithm will actually not only give you an extremely clean 1080 image, it will actually have a staggering amount of color information per pixel (there's a demonstration somewhere showing how it compares to 4:4:4 recorded at FHD per channel). I guess this isn't relevant if you intend to deliver in 4K, but this is generally how at least one person I know uses the smaller cameras in tandem with the big boys.

- the A7 picture is amazingly sharp, but large single color areas like the blue sky are awfully noisy and banding. Even the "low light king", the A7Sii, produces "busy pixels" - and that's in full sunshine! None of this clips could be of any use without serious NR, which kills the main picture virtue: the sharpness and resolution I mentioned

I assume you were shooting S-log. Its true, S-log tries to record far too much information for the weak codec to handle. The 8-bit 4:2:0 container ends up producing dither-style noise. This is not actual gain noise (as you know, since the A7S has one of the cleanest sensors otherwise), but rather that picture profile being badly paired with the internal codec. I've been told it is far better when using an external recorder because the codec and color space are improved, but personally I stopped trying. I stopped shooting Slog internally after my initial experiments were underwhelming, and now I don't shoot with it externally either. Too much hassle, as much as I love LOG on other cameras. Now, I just use a flat profile when I want some extra color space, or (heavens help me for admitting this), turn picture profile completely off on shoots that I don't plan to heavily grade. Resulting image is clean as a whistle, and will still hold up to very basic grade if necessary.

- when I tried to match those clips' colors to my FS7, the A7 picture fell apart very quickly - I dare say due to only being 8bit. There has been only so much I could do to the A7 picture without loosing color "density" (if this is a right word to describe what I mean; there's not enough "meat" in color information).

I recommend you try the 4:2:2 HDMI out with a better codec before you blame all your negative experience on the 8-bit part.

 

[moldcad]

Thanks for that info, M. I have just purchased the Shogun Inferno, and will be testing my friends A7sii further

Piotr

 

[M. Gilden]

report back and let us know what you think!

 

[Bern Caughey]

Responses:

-(As Sam stated) the LUMIX 12-35/2.8 yields the equivalent FOV of FF35 24-70mm & when used wide-open produces the DOF @ f/5.6.

-AKAIK in video mode none of the SpeedBooster allows autofocus on the GH bodies.

-The LUMIX lenses fly-by-wire focus rings are non-linear so repeatable focus pulls are practically impossible.

 

[markoconnell]

FWIW I use the GH4 as well as the FS7 and will certainly buy a GH5. The 12-35 is an excellent lens though not always as wide as I'd like. I bought a Rokinon 7.5 to have something wider, not really expecting much, and I love it.

 

[moldcad]

A super-wide and fast prime, followed by my Canon EF 16-35mm (becoming some 20-45mm) and 24-70mm (becoming some 31-90mm on Metabones Speed Booster XL 0.64x, provided it works with the GH5*), then followed by the native Lumix 35-100mm (70-200mm in FF terms) F2.8 - MFT lens (the new one, making full use of the new GH5 IBIS) would be a better combination of focal lenses, covering some 15 to 200mm range and all at F2.8 speed... The rationale behind this choice being:

- my F4.0 Canons become faster by 1.3 stops
- the 5-axis hybrid IS is available at the longest (telephoto) focal range, where it's needed most

* Still waiting for a confirmation from Metabones

Piotr

 

[wschmid]

Thanks for that info, M. I have just purchased the Shogun Inferno, and will be testing my friends A7sii further

Unfortunately, that is the wrong combination to my opinion. The A7sii will deliver 8bit only to the recorder, I am not sure if that will be 420 or 422 too. So from that side I think that such a combination will not deliver you what you wish.

But the GH4/5 with the Shogun/Shogun Inferno allows you to record to ProRes, and beside that this is 10bit 422 it is much easier to grade. However, since I have also the GH4 Shogun 10bit ProRes footage to my opinion the FS7 still delivers footage that can be graded with more reserve, given the better sensor. So I would test the GH5 in combination with the Shogun Inferno when the GH5 is available. Before that you will not be able to come to a sound decision about the B camera question.

 

[ChristopherA]

I haven't tested the A7Sii personally, but I found this video: http://www.learningvideo.com/10-bit-vs-8-bit/

There are a number of problems with some of the things he says, but the overall conclusion about the camera is correct. The A7Sii outputs an 8-bit 4:2:2 4k image over HDMI. The 4k 8-bit 4:2:2 signal compares very favorably to a 1080p 10-bit signal and is very usable if you are mastering in HD.

 

[M. Gilden]

Unfortunately, that is the wrong combination to my opinion. The A7sii will deliver 8bit only to the recorder, I am not sure if that will be 420 or 422 too. So from that side I think that such a combination will not deliver you what you wish.

We stated above that it will be 4:2:2. This is well documented.
That was point of suggesting trying the external recorder, otherwise it wouldn't be much of an improvement over the internal recording. Well, that's not entirely fair, the external recorders usually use much more robust codecs which will retain more color information and less compression artifacts. But the really exciting difference is the 4:2:2, and this is why we've been using the external recorder on Sony cams (especially for chroma key work). It makes a noticeable difference when grading versus the internal footage.

But the GH4/5 with the Shogun/Shogun Inferno allows you to record to ProRes, and beside that this is 10bit 422 it is much easier to grade.

The only difference then would be 8bit versus 10. Once he is no longer using the internal codec of either camera, the case to maintain a incompatible camera system seems to lose much of its steam. Once he is buying an external recorder, and is recording 4:2:2 with a much more robust codec, is the difference between 8 and 10 bit noticeable? I'm sure there's a difference, especially with smooth gradients and what not, but I'd strongly lead to it no longer being THAT big of a difference. The OP was disappointed comparing his FS7 image to the internally recorded A7S one, but going external solves the weaker color resolution and codec. I'd argue that's already going to make enough of a difference that he can push the grade more, and be able to maintain compatible lens systems. I can't say for certain since I'm not the OP, but its relatively easy to test right now since this equipment is out there and readily available.

I haven't tested the A7Sii personally, but I found this video: http://www.learningvideo.com/10-bit-vs-8-bit/

There are a number of problems with some of the things he says, but the overall conclusion about the camera is correct. The A7Sii outputs an 8-bit 4:2:2 4k image over HDMI. The 4k 8-bit 4:2:2 signal compares very favorably to a 1080p 10-bit signal and is very usable if you are mastering in HD.

True, there is an interesting explanation showing how color channel downsamples resolution here:
http://www.eoshd.com/comments/topic...rfect-green-screen-work/?page=3#comment-44031

The difference between them becomes very small, nearly non existant, once you downsample.

 

[moldcad]

Thanks guys for your further enlightening comments; I really appreciate them. One thing is for certain though: I'm not going to downsample to 1080p, so this way of obtaining enough color depth and resolution is out of question. I'm very pleased with the quality of my Inferno DNxHR files from FS7 - even those with only 8bit 420 color which HDMI output is capable of at frame rates higher than 30 - so it's quite possible A7 footage recorded in 8bit 422 to the Inferno will be equally good. But since we're only 2 months before the GH5 hits the shelves, I've decided to give it a try and only then make up my mind finally; should I find the MFT format limiting, or the GH5 picture noisy or unsatisfactory in any other way, I'll go for the A7...

Piotr

 

[M. Gilden]

Thanks guys for your further enlightening comments; I really appreciate them. One thing is for certain though: I'm not going to downsample to 1080p, so this way of obtaining enough color depth and resolution is out of question. I'm very pleased with the quality of my Inferno DNxHR files from FS7 - even those with only 8bit 420 color which HDMI output is capable of at frame rates higher than 30 - so it's quite possible A7 footage recorded in 8bit 422 to the Inferno will be equally good. But since we're only 2 months before the GH5 hits the shelves, I've decided to give it a try and only then make up my mind finally; should I find the MFT format limiting, or the GH5 picture noisy or unsatisfactory in any other way, I'll go for the A7...

Piotr

Makes sense to me. Do come back and let us know what you think.

Although, if your goal is to find a compact camera to compliment your FS7, I'd argue you can try the external HDMI out with the A7 right now, and see if it edits nicely alongside your FS7 footage. If it does, I don't see any reason to wait months for the GH5 to come out only to see if it ALSO grades well, and then proceed to invest in an entirely new lens system. If it doesn't, or if it gets "close but not close enough", I wouldn't blame you for waiting out the GH5 release to see if it gets better.

Don't get me wrong, I've owned about 4 or 5 Panasonic GH cameras and I loved them for what they were... and the Gh5 sure seems like a winner that I'm personally excited about. But from personal experience owning both MFT and E-mount (and Canon), I found it very frustrating using and maintaining multiple distinct lens platforms incompatible with each other if you want at least some native glass on both. At least my native Canon glass could be adapted to MFT and E mount, but to each other not so much.

 

[wschmid]

I'd argue you can try the external HDMI out with the A7 right now, and see if it edits nicely alongside your FS7 footage. If it does, I don't see any reason to wait months for the GH5 to come out only to see if it ALSO grades well, and then proceed to invest in an entirely new lens system. If it doesn't, or if it gets "close but not close enough", I wouldn't blame you for waiting out the GH5 release to see if it gets better.

What should be the advantage for him to record A7 footage external by HDMI/Shogun Inferno? It is internal 8bit, and it is external 8bit.

Especially for what he is looking for (10bit HDR footage), a 8bit camera will be the wrong approach!

 

[morgan_moore]

Here is the nikkor 50 on the GH4 and.. well I cant remember on the FS7, probably a nikkor 24 and speedbooster

the FS7 is the wide which makes matching easier.. (shot in an office on paper BG with 6 redheads)

 

[M. Gilden]

What should be the advantage for him to record A7 footage external by HDMI/Shogun Inferno? It is internal 8bit, and it is external 8bit.

Especially for what he is looking for (10bit HDR footage), a 8bit camera will be the wrong approach!

Perhaps I missed something, but I don't get the impression that is the OPs goal.

He wanted something that could shoot alongside his FS7 and grade well. He looked into cameras with the same mount for obvious reasons, such as the A7 series, only to find that the internally recorded 4:2:0 8-bit XAVC-S didn't hold up as well to a heavy grade, which is what made him start looking elsewhere. The goal isn't to get 10 bit HDR footage, its to get something that will more closely resemble and act like his FS7 footage when grading.

I would agree, if he were just a gear head who wanted the best specs on paper for color information, the GH5 is the best value per dollar- especially if considering just the internal codec. But he's trying to match a SONY camera. And the truth of the matter is, while I'm sure the internally recorded 4:2:0 XAVC footage couldn't survive a major push, the externally recorded 4:2:2 DNxHD or ProRes actually might hold up remarkably well. Since the OP has also said he is interested in buying some native lenses for advanced functionality, I would therefore think it is a silly move to invest in a new system with new lenses that are totally incompatible with what he has now, and color science that is totally different from what he has now (the extra color information is helpful in that regard, but its even more annoying when you are starting with different colors, and this is speaking from experience matching Sony and Panasonic)... all in the name of 10-bit versus 8.
All I'm saying is, if a Sony externally recorded would already give him what he needs, it would make much more sense. So I suggest trying it. Does that seem like such a wrong approach to you still?

 

[deltoidjohn]

Here is the nikkor 50 on the GH4 and.. well I cant remember on the FS7, probably a nikkor 24 and speedbooster

the FS7 is the wide which makes matching easier.. (shot in an office on paper BG with 6 redheads)

Wait... did you just post a black and white video to show how well 2 different cameras can be colour matched?

Perhaps you should be working in the marketing department for these camera companies! "Look how well the resolution of the FS700 matches the Red Helium... when viewed at 480p!" And "look how well this 8-bit footage matches RAW... when shooting a black screen with the lens cap on!"

:grin:

 

[moldcad]

Perhaps I missed something, but I don't get the impression that is the OPs goal.

He wanted something that could shoot alongside his FS7 and grade well. He looked into cameras with the same mount for obvious reasons, such as the A7 series, only to find that the internally recorded 4:2:0 8-bit XAVC-S didn't hold up as well to a heavy grade, which is what made him start looking elsewhere. The goal isn't to get 10 bit HDR footage, its to get something that will more closely resemble and act like his FS7 footage when grading.

I would agree, if he were just a gear head who wanted the best specs on paper for color information, the GH5 is the best value per dollar- especially if considering just the internal codec. But he's trying to match a SONY camera. And the truth of the matter is, while I'm sure the internally recorded 4:2:0 XAVC footage couldn't survive a major push, the externally recorded 4:2:2 DNxHD or ProRes actually might hold up remarkably well. Since the OP has also said he is interested in buying some native lenses for advanced functionality, I would therefore think it is a silly move to invest in a new system with new lenses that are totally incompatible with what he has now, and color science that is totally different from what he has now (the extra color information is helpful in that regard, but its even more annoying when you are starting with different colors, and this is speaking from experience matching Sony and Panasonic)... all in the name of 10-bit versus 8.
All I'm saying is, if a Sony externally recorded would already give him what he needs, it would make much more sense. So I suggest trying it. Does that seem like such a wrong approach to you still?

Words of wisdom again, M.

I'll tell you what guys: I've always been a sort of fatalist in my life, so I'm prone to treat the GH5 excellent specs' announcement as an omen, and a signal to wait... I did order one to put me on in the queue with my reseller, but didn't pay any deposit - and I hope before I'll have to make up my mind, Sony will come up with their own announcement of an A7 successor also capable of UHD@50p 10bit 422 at least externally - while offering all the advantages M. is mentioning (the best possible compatibility with my current gear, plus both FF and APS-C formats to choose from). Sure such a camera will not be available for several moths to come - but it WILL come, sooner or later... And this I'm trying to look at as another advantage: while I'm waiting, my bank account will be able to recover from my recent heavy investment into the Shogun Inferno and the most silly priced XDCA adapter/V-lock batteries which I had to buy in order to be able recording UHD@50p 10bit 422 on the Shogun.

Speaking of the latter: I'm simply in awe how much cleaner the Inferno's DHxHR picture is when compared to my FS7's internal XAVC-I. All this "noise and banding in the shadows" of S-Log1/2 problem - so annoying with XAVC - is simply non-existent! I have no idea whether this is just due to the higher bitrate of DNxHR HQX, or whether this codec is simply so much better than Sony's - but the difference is day and night. Enough to say that while most of my XAVC-I S-log footage I've had to run some NR on in Resolve (especially if I had to zoom in a little as part of stabilization process), the DNxHR doesn't require any NR at all (so far)...

Which paradoxically makes my B-camera choice even more difficult, because - and I tend to agree with M.'s arguments again - it's quite possible that even at 8bit, the picture from existing A7 - when recorded 4:2:2 on the Shogun - wouldn't leave much to be desired. Therefore - while waiting for the GH5 to arrive (and for some leaks from Sony about a new FF Alpha) - I'll certainly try to rent an A7Rii or A7Sii to try them out with my Shogun (something many of you guys would have already done by now, but here in Poland - with the market still not being matured enough - is not just a piece of cake).

Exciting times!

Piotr

 

[wschmid]

First of all, Pitor has committed himself to a clear HDR workflow. It is up to him to deny or to confirm that, but over the time that is what he has done and written in a lot of forums. So you should not argue that HDR is not the goal, if HDR is the goal for him. And HDR without 10bit - well, it will not fly.

And the truth of the matter is, while I'm sure the internally recorded 4:2:0 XAVC footage couldn't survive a major push, the externally recorded 4:2:2 DNxHD or ProRes actually might hold up remarkably well.

I would not recommend to run an external recorder like his Shogun Inferno for a 8bit camera. It simply makes no sense. At the best you have a better color sampling 422 instead of 420 - but that is all what you can expect. So it is not worthwile to record 8bit externally with such a camera - all what you end up are larger files and a limited benefit. And you cannot compare the A7 footage with our XAVC I footage from our FS7 units really.

Since the OP has also said he is interested in buying some native lenses for advanced functionality, I would therefore think it is a silly move to invest in a new system with new lenses that are totally incompatible with what he has now, and color science that is totally different from what he has now (the extra color information is helpful in that regard, but its even more annoying when you are starting with different colors, and this is speaking from experience matching Sony and Panasonic)... all in the name of 10-bit versus 8.

Sure, with lenses you have a point - at the first look. But I would use the lenses from the FS7 and invest in a converver like the Metabones Speedbooster for MFT, and I am sure that Metabone will come up with such converters also for the GH5. That brings additional advantages that are wellknown from the Speedboosters.

Sure, the color management of Sony and Panasonic is different. Very different. But it is quite simple to use tools like x-Rite ColorChecker, shoot some comparions charts and use Resolve to come up with compensation LUTs. And the 10bit will deliver the possibility to grade the GH5 footage as required, to adjust it in the best possible way to the FS7 footage.

Sure, if Sony would add a new camera that follows the Panasonic trend to record 10bit internal, or - at least - that delivers 10bit by SDI or even HDMI externally, that would be the better approach for a B-camera to the FS7. But up to now I have not read anything about such a move by Sony. And I am not sure if such a move will come.

All I'm saying is, if a Sony externally recorded would already give him what he needs, it would make much more sense. So I suggest trying it. Does that seem like such a wrong approach to you still?

He has the Shogun Inferno by now, why should he purchase one of the overpriced Sony recorders? If there is the possiblity to test the Shogun with a GH5 and see how that can be aligned with the FS7 - sure, that is a valid approach. But even to test the 8bit Sony cameras with the Shogun is a waste of time, to my opinion. At least as long as Sony sticks to the 8bit.

 

[morgan_moore]

Wait... did you just post a black and white video to show how well 2 different cameras can be colour matched? :

The thread is about lenses.. I just thought I would share an actual job and the fact that when one does a tight on the GH4 and a wide on the S35 camera cheap lensing seems to be no issue.

 

[moldcad]

First of all, Pitor has committed himself to a clear HDR workflow. It is up to him to deny or to confirm that, but over the time that is what he has done and written in a lot of forums. So you should not argue that HDR is not the goal, if HDR is the goal for him. And HDR without 10bit - well, it will not fly.

I do not deny, Wolfgang - indeed, most of my "production" is HDR nowadays (whenever appropriate) - and indeed, I'd like to stick to it. And I realize 10-bit is much better fit for the purpose than 8-bit (some even say it's a bare minimum, 12 bit being what would really "fly" in grading).... This is why - even though I already had the A7 on order - I cancelled it the day Panasonic revealed the GH5 specs. That said, however, HDR is just one of my many goals. This is why I said in my previous post that an A7 successor - a Full Frame Sony E-mount camera with 10 bit UHD recording - would tick all my boxes, and I'm hoping for it to be announced soon.

The thread is about lenses.. I just thought I would share an actual job and the fact that when one does a tight on the GH4 and a wide on the S35 camera cheap lensing seems to be no issue.

Very true, Sam - this particular thread I started right after the GH5 was announced, and not having much experience with lenses other that FF or APS-C (MFT in particular), I was seeking advise on that aspect in case I actually go for the GH5 because of its 10-bit recording. I never thanked you for explaining to me the "35mm stills camera" equivalent of MFT lens focal range, so let me say thanks now But again - even though this thread's title is about the lenses, it's just one of the many elements of the puzzle.

I appreciate it very much that this thread - after several others I started lately, all related to this puzzle of picking the right B-cam, have gathered lots of patronizing and/or mocking comments from others - has evolved into a very interesting, serious and extremely helpful discussion. Thanks to the input of M., Sam and Wolfgang (sorry if I omitted anyone). Thanks guys!

Piotr

 

[moldcad]

Ha! So here it goes:

http://thenewcamera.com/sony-new-high-end-ff-camera-coming-in-next-few-months/

Piotr