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[huaza]

I am a bit confused about the new Gemini 4:4:4 recorder from Convergent Design and if it would have a benefit as opposed from recording to SxS prores 4:4:4 in camera with the Alexa.
I have been told there is NO advantage but would like to get others knowledge on this subject.

I believe the Gemini is 10-bit and ProRes 4:4:4 on Alexa is 12-bit. So is the Alexa by itself better than the Gemini at the end of the day?

[adrianjebef]

There will be a huge quality benefit to recording with CD's Gemini 4:4:4 as the Gemini is an uncompressed recorder capable of full color and eventually ARRIRAW. I have seen tests between ProRes 4444 vs Uncompressed vs ARRIRAW.  The differences are slight yet noticeable.  The biggest benefit will be the ability to resolve finer detail.  Blades of grass shot on a wide (27mm Master Prime) lens will appear MUCH sharper with an uncompressed or ARRIRAW recording vs compressed ProRes. This additional clarity is especially helpful for VFX work.  I wouldn't concern myself much with 10-bit vs 12-bit.  As the Gemini is capable of recording 2K and eventually ARRIRAW you'll get 12-bit soon enough if you want it.

[Jamie Metzger]

"the biggest benefit will be the ability to resolve finer detail.  Blades of grass shot on a wide (27mm Master Prime) lens will appear MUCH sharper with an uncompressed or ARRIRAW recording vs compressed ProRes."

I've heard that it makes a huge difference when projected, as Arriraw looks quite amazing on the big screen. That's heresay though.

The whole battle between 4:4:4:4/10-bit/12-bit/uncompressed...etc is really up to Post. Most places claim to know what they are doing, and then you see your beloved commercial, Shot in Arriraw and then Aired on National TV in Standard Def.

The Gemini seems sweet, but do people really want uncompressed? I know of a few TV productions shooting HQ and going to 4x4 only for VFX work. I think uncompressed for the Alexa is unnecessary when you consider that HQ is more than adequate for broadcast/web and Arriraw is meant for the bigscreen. Where does uncompressed fit, in the Alexa world?

[Nick Shaw]

The Gemini seems sweet, but do people really want uncompressed? I know of a few TV productions shooting HQ and going to 4x4 only for VFX work. I think uncompressed for the Alexa is unnecessary when you consider that HQ is more than adequate for broadcast/web and Arriraw is meant for the bigscreen. Where does uncompressed fit, in the Alexa world?

Compression does not automatically mean loss of fine detail – it is image dependent. But if in doubt uncompressed is better than compressed (all other things being equal) and uncompressed RAW is better still. It basically comes down to your budget and the practical necessities of the shoot and post for a given production.

[huaza]

Thank you all for your answers.
I have actually contacted Convergent Design and also Abel Cine directly and they both tell me that there would be no substantial benefit from recording with the Gemini 444 as opposed to the in-camera Alexa ProRes 444 option. So that kind of seals the deal for me.
This would be for a feature film to finish on 35mm, etc. So I guess its either ArrRaw(Codex, OB-1)  or ProRes 444 if we go with the Alexa.

[Jamie Metzger]

Huaza,

Don't overlook the most important part, is that the Codex can record 2560x1620 ArriRaw. This extra resolution is what you would be looking for when shooting a feature. Also, utilizing the LogC (film matrix), but you should definitely test.

[adrianjebef]

Don't underestimate the benefit of an uncompressed recording.  Yes, the difference is slight. But THERE IS a difference. I have personally tested many lenses and recording methods with the ALEXA.  You would be surprised how much sharper an image this camera can make when paired with Master Primes, the new Leicas, and an uncompressed workflow.

I personally believe we will be entering into an uncompressed world within the next 6-12 months.  Read/Write speeds have increased, so has transport technology (like Thunderbolt).  CD is very future-forward in their thinking.  It is not just about the difference between ProRes, Uncompressed, and ARRIRAW.  It is now an entirely new workflow ideology.  There are many interesting things that the Gemini can do.  Consider recording uncompressed Log C to Slot 1 and uncompressed w/ a LUT to Slot 2.  You would have a dual recording with (hopefully) matching filenames, timecode, and audio sync.  With a fast enough Mac Pro (or whateva) and some Thuderbolt Raided Drives you'll be able to archive the Log C material as a master and transcode the LUTed material into any file type you'll need for editorial (ProRes, DnX, etc.)  It is an elegant solution that provides maximum quality and maximum flexibility.

[Jamie Metzger]

Interesting ideas Adrian.

I initially thought that the Gemini could record one stream uncompressed and the other stream in prores or mxf formats. I was super pumped at that idea, but I have no clue what led me to believe that.

Yes, you are correct that two streams of uncompressed, one for transcoded dailies and one for your master (lots of data, no?) is a great solution. The part that kills me about any transcoding that isn't with a red rocket is the time it takes.

[adrianjebef]

Thought I'd revive this post since the Gemini has shipped.

I've got two Gemini 444's and have been pairing them with ALEXA's on my last few shoots. As I stated earlier, the difference between uncompressed and ProRes 4444 is slight but noticeable. ProRes is a great codec as is the new DnX 444 codec from Avid. However, uncompressed will always beat either anytime. The ALEXA is a top tier 2K/HD digital camera and it makes sense that we should get the best quality recording from it. The most exciting thing about the Gemini is its ease of use and price point. The Gemini is extremely stable. It's works. It's simple and small. And it's fast. You'll definately want a raided storage system to offload the uncompressed footage to. But a 4TB G-Raid (or similar) will handle the task even with just a laptop. And don't forget that uncompressed footage can be transcoded quite quickly if you have a fast storage system (ie: 4 HDDs in a Raid 0). So, yes, a Mac Pro with internal/external raid is highly recommended but it's also totally doable with a laptop (offload only no transcodes...)

And how about image quality? The one thing we actually care about? Uncompressed is the way to go. This is most apparent in low-light scenes like night exteriors. As the exposure nears the camera's noise floor ProRes compression just adds to this problem of visible "grain". I shot some scenes inside the San Francisco Opera House recently. 800 ISO and just ambient dimmed house lights (as it would be during a performance). The uncompressed DPX footage from the Gemini 444 was noticeably cleaner than the ProRes 4444 clips.

CD's storage prices are also extremely fair. Consider their 256GB SSD at $750 compared with RED's at four times the cost. And how much will the new Sony SR cards run? I bet they price out close to RED's SSDs. The Gemini 444 is new on the scene and I'm already extremely happy with this tiny thing.  Audio and metadata support should be coming before the end of the year.  And Gemini ARRIRAW support is on the near horizon...

[robstiff]

Thanks for the insight! Can the Gemini capture 2K 444 Uncompressed from the Alexa?

[Snehal]

Just my 2 cents - Uncompressed and RAW are much better for VFX as colors are more accurate and there are no artifacts.  Here's one phenomenon - in a compressed codec like ProRes and DNx, you may find a fine line separating contrasting details.  For example, you might have a 1pixel wide line drawn to separate a spotlight on a wall from it's dark surroundings.  This line is created by the compression codec in order for it to separate colors into groups before it figures out the mathematical formula to represent that patch of color.  This line will not exist in a RAW version of the same recording.

[adrianjebef]

Rob, the Gemini is a 2K capable recorder. Unfortunately at this time the ALEXA does not output 2048x1080 via the Rec Out. I've asked ARRI a few times over the past 6 months to implement a 2K Log C output but haven't heard any real response so far. The truth is an uncompressed 2K Log C master via a Gemini or another external recorder would give you a perfect 1.85 theatrical frame without having to crop and blowup the standard 16x9 aspect. ARRIRAW is great but it requires a proper post setup to view and produce dailies. Unless I'm shooting Transformers 7 I'd much prefer to work with uncompressed Log C. It's just way easier to deal with and I find the Log C encoding gives me more than enough range for final color-correction. ARRIRAW can be over kill unless you need the added resolution for VfX.

I know we've all gotten used to compression via ProRes or DnX or even R3D but uncompressed really is the way to go for high-end work...

And what do you think Snehal? Any chance we'll see a proper 2K 444 Log C output from the Rec Out sometime in the near future?

[Michael Borenstein]

Adrian,

I hope you're well and you had a good new years.

There are no plans on the roadmap to output 2k x1080 right now.


Regards
Mike

[adrianjebef]

Ouch, that's unfortunate. Perhaps I'll need to start an Internet petition...

[Dan Keaton]

Dear Friends,

There are good, technical reasons to record ARRIRAW.

The image quality is definitely better and the file sizes are actually smaller than full uncompressed 4:4:4 RGB DPX files (in 1920 x 1080).

We are making great progress on our ARRIRAW Option for the Gemini 4:4:4.

We are way ahead of our original schedule, which as for deliveries of this extra cost option in April 2012.

We have a few minor items remaining, then we will submit a Gemini 4:4:4 with the ARRIRAW Option to ARRI for certification testing.

We perform the real time debayer while recording and on playback of the recorded ARRIRAW files.

Thus, you can monitor, as expected, on our built-in 5.0" LCD as well on an external Monitor. The Debayered image will be full size, 1920 x 1080, not a smaller size image.

We will make announcements via press releases and on our website.

Dan Keaton
Convergent Design
www.convergent-design.com

We provide live, knowledgeable, support 24/7 every day of the year.
My phone numbers are listed at the bottom of this link
http://convergent-design.com/Support.aspx