11.18.2017

"Memory is getting so cheap these days that file size doesn't matter any more." LMAO, ROTFL,

Behind the scenes at a three camera interview.

We decided to shoot a video project with multiple GH5s over the last two days. We also decide to shoot in 4K and to shoot 10 bit and 4:2:2. If you do that you'll quickly find that while the GH5 camera is a robust and stable platform it does demand fast memory cards in order to push through high density video signals. I'd been using UHS-1, class 10 cards with 95mbs write times but found out the hard way that once you go with big files your SD memory card speed has to upgrade with you...

Here's what I learned: You can get away with using slower cards in certain situations. If the camera doesn't move. If the talent doesn't move very much. If you don't shoot stopped way down (which vastly increases the detail in video files, increasing dynamic file size) and if you aren't recording with all the available camera bells and whistles on. If you are running next to a subject who is also running and you are shooting at f16 and you have image stabilization engaged. Your crappy UHS-1 card will sooner or later generate a camera screen message that says "Recording was cancelled due to slow card write..." Or something like that. 

What other things stress the system? Well, how about automatic diffraction compensation? Better to just shy away from apertures smaller than f8 and to keep this control off. Same for corner shading compensation. Just click "no." Some of the bells and whistles slow the whole process because the internal processors have more to do but the biggest culprit is cards that just can't suck up data fast enough. And, since you paid for all those other features you might feel entitled to use them....

In that case it is incumbent on you to supply your previously deprived camera system with a kick-ass fast SD card. If you are planning to take advantage of everything the GH5s have to offer you might use in-camera, 400 mb/s, All-I files as the gold standard to shoot for as a performance target. To play on this playground you are going to need a card with the following attributes: It should be a UHS-II card. That means it will have a second row of gold electrical contacts just below the usual UHS-I contact configuration. The UHS-II cards are speedier at reading and writing (anyone want to explain the technical reasons? We've got room in the comments....). The card should have a V90 rating. This is, as far as I know, the top rating for current SD cards. Oh, and you'll need a write time about 3-4X faster than a really good "Extreme" UHS-I card. Ready, set, let's drop $100 per card for 64 Gigabytes.... Or $278 for a 128 GB card...

The $100 price tag is just about double the price of previous generation of 64 Gb cards which  I purchased. So maybe memory isn't quite as cheap as the pundits proclaim....

But wait! There's more! Each GH5 comes with two card slots and unlike some of their less well spec'd brethren both of the slots are UHS-II ready. This means that if you are using two cards for simultaneous back-ups your camera can only write as fast as the slowest card can accommodate. This means that in practice you'll want/need to have a V90 UHS-II card in both slots. Now you have $200 per camera for basically the same 64 GB. Shooting three cameras deep and begging for simultaneous back-up? That's three cameras X $200 per camera or about $600 for a little over thirty minutes of 400 mb/s All-I shooting. That's $1200 per hour. More or less. Thank goodness the cards are re-usable. 

We opted for a lower intensity codec on this project. One with an average throughput of 150 mb/s. But a faster card makes for a more responsive camera system whether you are shooting big video files or slamming through a bunch of raw photo files. The faster the card the better advantage you can take of a big, fast buffer. After all, you paid for it....

Even if you never shoot a lick of video a good UHS-II card with a fast rating will make your raw+jpeg shooting Texas Jackrabbit fast. Even as it puts your credit card on a hard diet...

I'm using a combination of Delkin 128 GB, V60 cards and two Hoodman 64 GB, V90 cards at the moment. I'm sure it's advertising bravado but Hoodman labels them as 2000X cards. 8K, ultraHD capable. Guess if I want to be a really serious pro I should buy another handful...


I'd buy the 128 GB cards but they're way too pricey...




9 comments:

  1. I bought two of the 128G cards for my G85. Peace of mind is worth it IMHO.

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  2. So...how about the Atomos outboard recording units? Can one of those handle this deluge of data without choking? And, if you pipe directly to the Atomos while running an internal SD card at the same time, will the write speed of the SD card limit the whole system? Even if the outboard recorder could deal with the flow on its own?

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  3. I have said that thing about memory is cheap, but not to anyone doing high-end video. I knew high-end cards were expensive, but didn't realize they were that much.

    Still, when I start to whinge about the cost of digital I remind myself what I used to spend on film and processing back in the day. That petty well stops my complaining.

    But even for someone being paid commercial rates I can see where these prices hit the profit margin a bit. And then there is the drive storage and computer power once you start to edit. Will that be another hit?

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  4. MM, For the initial interviews inside we could have used the Atomos recorders. The SSDs are rated at something like 480 mb/s write speed so we would be in good shape for that. The SD card in camera could still gum up the works. When shooting 4K 422 10 bit to the Atomos the in-camera files are limited to 8 bit 420. At 400 mb/s All-I the camera only writes either to the internal card or to the Atomos but not both.

    The big issue for me yesterday was that 90% of the day was spent handholding the camera and shooting in bright daylight and open shade. Adding the weight and bulk of the Atomos with batteries etc. would have been a real impediment to shooting fast. Also would have required the sunshade in order to view the screen well. That adds a ton of bulk.

    Most of yesterday involved documentation of interviews with the homeless so the smaller the profile of the camera system the better. Discretion beating ultimate image quality by a long shot.

    With the newer V90 cards we are now able to shoot at any setting the cameras can toss our way. Interiors and especially tripod work will see us using the Atomos recorders but for handheld it's hard to beat the very, very good EVFs of the GH5s and the low profile (both size and weight). I could not see going handheld all day long with something like an FS7 or an even bigger rig.

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  5. Gato, I agree with almost everything you've written BUT it's good to remember that back in the film days film and processing was a net plus for working photographers. We would markup the film and the processing so we were making an extra 20% over the cost to cover testing, etc. It was a solid profit for most of the work and the clients paid it because that was the standard of the day.

    In today's scenario I would be interested to know how other photographers engineer their billing to cover the (now) recurring cost of memory card upgrades.... Anyone?

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  6. Eric, I agree totally. Most of my "legacy" cards are fine for my kind of photography but boy oh boy they do show their weakness when shooting video. Especially when everything (camera, subject, background) is moving around... More fast cards please!

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  7. when using a gimbal, rotating, tilting and panning i stil prefere HD over 4k for overall quality. because of rolling shutter. And none of my clients request 4k yet. So i can still use all my memory cards. But i hear gh5 can handle rolling shutter in 4k much better?

    so when i get request for moving 4k i think the gh5 is in my price range to ;) i dont need the newest stuff, i need the stuff that deliver what i need to output!

    gx80/85 combined with a fz1000 if i need the reach is more than good enough right now;) But i might get a gh5 used when gh6 or even gh7 comes out!

    experience and advice from this blog thought me that lesson. I make better and better imagery with cheaper and cheaper gear;) a combination of used gear that used to be state of the art and is now surpassed by newer versions. Like my 1d III and 5d II both brought used for about 375$. And new tech like gx80/85 that sell new dirt cheap already from new because it misses the last 5% in stats.

    Im so glad i can learn from your gear adventures Kirk! i brought my fz1000 and gx80 when you were still an all sony shooter. So went the same route as you prior to You. but my decision was partly influenced by your thoughts. And the joy of photography both professionally and in private raised a lot due to me changing up my gear (not using more money but actually getting some spare money in the exchange). And i can cover more kinds of jobs now.

    Thanks again for blogging

    Cheers Mads

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  8. Kirk
    Your insight is more valuable than so many other bloggers because you are out there everyday making a living as a working pro while so many others lack the real world experience. You do a great job, keep it up!
    Dan

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  9. I just discovered this when I was getting ready to do some test clips for my upcoming project. I ended up getting a two pack of the Sandisk 128gb v90 Extreme Pro UHS-ll SDxc for $449 from one of the big photo suppliers in NYC. If I would have bought the two cards individually, I would have paid $50 more.

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