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On 6/6/2017 at 6:46 PM, majoraxis said:

I know what I want for Christmas -  iMac-Pro. The Apple product page mention 10bit color monitor and a brighter screen. I love my 2014 iMac with the GPU graphic card - it runs Resolve 14 well enough, but the magic for me (besides the screen) is I can carry it around from work to home and back in the original box and treat it like a laptop so to speak.  Anyways, having that much power in semi-portable system is fantastic... am I the only one who carts their iMac around (daily)?

And there you have your first kickstarter! A portable soft carry case for an imac;)

20 hours ago, BTM_Pix said:

The iLugger with wheels is pretty good for transporting iMacs 

The Lavolta is about a third of the price but is a bit less discrete....

 

wheel_back.jpg

Lavolta-Carrying-Case-Bag-for-iMac-01.jpg

Doh! Lol

Should learn to read entire thread before posting:/

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20 hours ago, joema said:

 I have a top-spec 2015 iMac 27 with multiple Thunderbolt 2 RAIDs (inc'l SSD), and I am constantly struggling with performance issues when editing H264 4k on FCPX. As fast and efficient as FCPX is, it's not sufficient to smoothly edit H264 4k multicam on a 4Ghz iMac.

Sure. You do use proxies for multicam then, don't you? But to be fair and put things into perspective: you then paid around $3200 for your machine with a fine display. My only way to directly compare my (same) iMac to other options is my best buddy's $10.000 HP 2015 workstation (sans monitors) with Adobe. He is a graduate engineer for AV media and formerly had been a full time Adobe teacher. He knows what he's doing. I always find he struggles more with performance, particularly playback. But it's a genuine workstation. The following is not an issue for him:

20 hours ago, joema said:

 It takes one *week* to transcode to proxy the content from the documentary I'm working on.

An iMac is the wrong machine for this task. And I assume the iMac Pro will also not be ideal for this. 

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1 hour ago, Axel said:

Sure. You do use proxies for multicam then, don't you? But to be fair and put things into perspective: you then paid around $3200 for your machine with a fine display. My only way to directly compare my (same) iMac to other options is my best buddy's $10.000 HP 2015 workstation (sans monitors) with Adobe. He is a graduate engineer for AV media and formerly had been a full time Adobe teacher. He knows what he's doing. I always find he struggles more with performance, particularly playback. But it's a genuine workstation. The following is not an issue for him:

An iMac is the wrong machine for this task. And I assume the iMac Pro will also not be ideal for this. 

Why would the iMac Pro be the wrong machine for transcoding to proxy? Just wondering, because I'm also seriously considering getting this machine as well. My 2013 iMac is pretty sluggish when it comes to 3rd party plug-ins like Neat Video too. 

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52 minutes ago, jonpais said:

Why would the iMac Pro be the wrong machine for transcoding to proxy? Just wondering, because I'm also seriously considering getting this machine as well. My 2013 iMac is pretty sluggish when it comes to 3rd party plug-ins like Neat Video too. 

This transcoding issue is exactly the question I've been asking myself. False info?

FCPX can transcode footage to a low quality proxy ProRes when you import it, furthermore you should down grade the editing quality of your footage. If you are editing H264, there isn't much point transcoding to proxy or using optimized media option - they can help with the GPU, but lots of debate about how much it speeds things up. You need to try different things for yourself.

If you're not using FCPX on your iMac - WTF!

As far as Neat Video is concerned, this has always been notorious for being very very slow to transcode - there are tweeks you can do to make it quicker (think this has to do with how many frames it matches up in order to clean up footage). Also, Neat Video has one of the best Sharpening Tools out there, which if i remember rightly you can turn off or on - is it on by default? can't remember. I stopped using it because it took ages to render & just learnt to shoot within the limits of the camera or added lighting.

Multi-Cam editing can be slow (really slow), but again you can lower the playback quality of your footage whilst editing. I have found it is better to use the multi-Cam function for smaller, really complex sequences. I'm on a mac a lot older than you guys & I create a seperate timeline, then just export the final sequence. I don't think that I would ever edit a whole piece with the Multi-Cam feature, but that's mainly because I can edit just as quickly in the old fashioned way.

And yes, I am looking to buy a new iMac, but not the Pro version.

Would be really interesting to hear from someone what specs you actually need for the normal iMacs....

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1 hour ago, jonpais said:

Why would the iMac Pro be the wrong machine for transcoding to proxy? Just wondering, because I'm also seriously considering getting this machine as well. My 2013 iMac is pretty sluggish when it comes to 3rd party plug-ins like Neat Video too. 

Neat is notoriously slow. I wonder if the maxed-out nMP has realtime with that. Who has? Please tell the rest of us!

What joema wrote about proxy encoding: he must have had many, many clips ("on multiple SSD raids" - this gives you an idea). Say, you have a library of 1 TB 4k H.264. That's many hours of footage, and you want to batch-transcode them to proxy. *One* clip is transcoded almost instantly, below realtime, AND FASTER THAN WITH A nMP. After a while, the fans turn on, the machine gets warmer and the performance decreases noticeably. Here's Max again:

Why? Because an iMac is not the right machine for this. Here is a trick, a little workaround I found out for myself: 

Keep the transcoding in the background, do some time-consuming foreground work. Meticulously favorite, tag, sort all clips. You can do that clip-wise without proxies, because this machines' strength is smooth playback of 4k H.264. Actually start editing (not multicam though).

In other words: Interrupt the transcoding process. Force it to pause. I had 140 GB H.264 footage, and it background-transcoded to Optimized AND Proxy in just a few hours. It was finished shortly after lunch. Rarely heard the fans.

But in the first place: decide whether proxy/optimized make any sense at all. Since, as is generally accepted, the computer has no problems to play back 4k H.264. No multicam? No Neat? No five, six and more different effects stacked (you can also right-click transcode selected clips only or render selected parts of the timeline)? Then stay native!

 

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8 hours ago, Axel said:

After a while, the fans turn on, the machine gets warmer and the performance decreases noticeably. Here's Max again....Why? Because an iMac is not the right machine for this...But in the first place: decide whether proxy/optimized make any sense at all. Since, as is generally accepted, the computer has no problems to play back 4k H.264. No multicam? No Neat? No five, six and more different effects stacked...Then stay native!

That video was the 2014 iMac 27. It was improved in 2015 (what I have) and Max re-tested it and determined it did not have the thermal throttling issues of the 2014 model. 

Re editing camera-native H264, I am a fan of that where possible -- lots of FCPX users needlessly transcode to optimized media. However for large quantities of H264 4k, you pretty much need proxy -- even if NOT multicam and without Neat or multiple effects. Even for single-cam material the skimmer is just not fast enough on a top-spec 2015 iMac 27 to blitz through large quantities of H264 4k content. If you play around with a 5 min 4k iPhone video, it's OK without proxy. If you have a long single 4k video (e.g, a classroom lecture) and all you need is chop the head and tail, you don't need proxy for that. But for evaluating and seriously editing lots of content, it's just too slow without proxy.

Re the iMac 27 is the wrong machine for large proxy transcodes, there really isn't a much better machine. A 12-core nMP has 3x the cores but they run at 2.7ghz so overall it's about 2x the CPU throughput, but without Quick Sync. It might not be *any* faster. And buying a four-year-old nMP now? Now *that's* the wrong machine.

By the same token the iMac Pro might not be hugely faster (for creating proxies) unless Apple figures out some way to use hardware acceleration for H264 decoding on a Xeon machine. But (like the nMP) it would be faster for various other editing and effects-related tasks.

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9 hours ago, joema said:

Re editing camera-native H264, I am a fan of that where possible -- lots of FCPX users needlessly transcode to optimized media. However for large quantities of H264 4k, you pretty much need proxy -- even if NOT multicam and without Neat or multiple effects. Even for single-cam material the skimmer is just not fast enough on a top-spec 2015 iMac 27 to blitz through large quantities of H264 4k content. If you play around with a 5 min 4k iPhone video, it's OK without proxy. If you have a long single 4k video (e.g, a classroom lecture) and all you need is chop the head and tail, you don't need proxy for that. But for evaluating and seriously editing lots of content, it's just too slow without proxy.

jompais and Bioskop.Inc ask about the contradictions in our statements. You work on very long features, mine never are longer than 10 minutes (weddings). I usually have around 100 - 150 GB of footage for one day's shoot, between 100 and 300 clips, and external audio. I optimize my selections on import, just in case. I never multicam, just tried it once in FCP X out of curiosity with old FCP 7 music video footage (ProRes). My machine isn't configured for that anyway since I have the 256 GB flash and my TB raid (Pegasus with HDDs) reads just below 500Mbps. 

Ever since I began editing in 2002, I never had the fastest computers, and additionally the old FCP could address only 2,5 GB RAM. Therefore, longer features (beginner's mistake) had to be split into chapter-sequences or else FCP became slow and would often crash. That happened most reliably when you scrubbed the playhead rapidly over a long timeline.

These two habits - structuring a story into sequences (even for ten minutes, I'll have three or four)  and not skimming rapidly in the timeline (if at all) - I kept. I limit the number of clips FCP X has to access at once - by filtering in the browser and by compounding chapters. I disable background rendering. CC, effects with seldom used Neat asf. I make the last stage, and once the edit is locked, I don't care too much if I lose realtime. I render selected and that's the extend of it.

To evaluate the usability of a system one has to know the workflows and demands of the people who report bottlenecks or not. I never found benchmark comparisons particularly useful for my stuff. With performance I just mean smooth playback and overall responsiveness, I just don't care if the final export takes an hour or a half. I don't sit there and stare at the progress bar.

 

 

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6 hours ago, Axel said:

...You work on very long features, mine never are longer than 10 minutes (weddings). I usually have around 100 - 150 GB of footage for one day's shoot, between 100 and 300 clips, and external audio. I optimize my selections on import, just in case. I never multicam....structuring a story into sequences (even for ten minutes, I'll have three or four)  and not skimming rapidly in the timeline (if at all) - I kept. I limit the number of clips FCP X has to access at once - by filtering in the browser and by compounding chapters. I disable background rendering....

I don't work on long features in terms of deliverable, but 4k documentaries with high shooting ratios and lots of multicam. In this era that's not unusual -- 4k GoPros and drones are everywhere, A and B cam are 4k, etc. I shot a wedding last year and we used lots of 4k multicam.

There is a major editing performance variation in various H264 codecs. E.g, the UHD 4k 4:2:0 100 mbps output from a DVX200, or Sony A7RII is very sluggish -- even in FCPX and on the fastest available iMac. By contrast the UHD 4k 4:2:2 300 mbps output from a Canon XC10 is also H264 but it's very smooth and fast to edit. I don't need proxy for that.

But I can't control what codecs camera manufacturers use, just have to deal with it. We have ProRes recorders but generally don't use them due to added complexity in the field. The bottom line is in an era when high shooting ratios and H264 4k are common, current hardware is often not fast enough without transcoding -- even for FCPX. This isn't just timeline performance but the ability to skim material, mark keyword and favorite ranges is greatly degraded. It is for these increasingly common cases the iMac Pro is needed and definitely not overkill.

Of course we defer compute-intensive effects to the very last step, but ultimately they must be applied *and* iteratively adjusted. Each tweak or adjustment to stabilization, Neat video, de-flickering, etc. must be rendered in the timeline to fully evaluate, and this is agonizingly slow on 4k. The greatly improved CPU and GPU performance for the iMac Pro is vitally needed for this.

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". The greatly improved CPU and GPU performance for the iMac Pro is vitally needed for this ..."

Well, financially I couldn't justify 5000 or 10.000 € for a new machine. My own stuff is indeed XAVC UHD, what I get from others (I also edit weddings) as well, and I don't see lags - but that must be the transcoding.

In the end, it's not a rational decision. I spend a lot of time every day facing the computer, and I want it to be sexy. So far it had been a good year. Maybe these greedy suckers will again get my money. There you have it, haters, I admit it. I'm a miserable consumerist Apple fanboy!

 

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This is all very interesting & it reminds me of when everything changed from SD to HD, the render times on FCP or AVID were very very long - the offset of this was that the BBC had a bar & as an edit asst you'd check in every pint to see how the final render/export was going.

The whole idea of having to transcode footage reminds me of those days - importing took hours & so did the final export.

I still wonder whether we are just expecting too much from computers, and NLEs, with the advent of 4K? Or is it down to us & have we just become a "Now" culture, where the idea of having to wait for something has become intolerable and completely unrealistic? It also leads to the question of whether people have got into bad habits with their workflows or never really learnt good workflow practices? Ask yourself this, when you import your footage, have you already selected your shots or do you simply import all the footage?

Anyway, the good news, according to iFixit, is that the new iMacs can be opened & the important parts (processor, graphics card etc...) are no longer soldered into place - so we can now upgrade the new iMacs...

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44 minutes ago, Bioskop.Inc said:

The whole idea of having to transcode footage reminds me of those days - importing took hours & so did the final export.

There is huge difference now. Do you remember?

Now you can transcode in the background and start editing right away.

44 minutes ago, Bioskop.Inc said:

It also leads to the question of whether people have got into bad habits with their workflows or never really learnt good workflow practices? Ask yourself this, when you import your footage, have you already selected your shots or do you simply import all the footage?

Whereas you can import all footage at once and immediately throw it into the timeline with FCP X now (even without transcoding, and, if you are fearless, even with naked files that are left in place!), it's not very smart. In my very humble opinion. This app offers us the best tools to prepare our clips for editing in the browser. In my eyes this is at least as crucial as the efficiency of the magnetic timeline. But I learned to respect the workflows of others. Mine also changes from time to time.

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On 6/8/2017 at 7:07 AM, Bioskop.Inc said:

 

Would be really interesting to hear from someone what specs you actually need for the normal iMacs....

As someone coming from a PC, that's my question, as well. More specifically:

Is the additional 4GB VRAM in the Radeon 580 of any real use for 4K editing? FCPX and plugins that interest me list 1GB as a requirement for 4K, so I'm wondering if 8GB VRAM is overkill. (I noticed that the 580 is the only card rated as "VR Ready." The cynic in me wonders if it's there primarily to allow Apple to advertise the iMac as "VR Capable." As someone with no interest in strapping on an Oculus Rift, would that money be better be spent on memory?

Is the hyperthreaded i7 required for relatively straightforward 4K editing (Canon XF-AVC Intra...though that's apt to change)? I've read anecdotal reports that recent i5 iMacs outperformed earlier i7's, so, again, is the i7 overkill?

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15 minutes ago, KrisAK said:

...Is the additional 4GB VRAM in the Radeon 580 of any real use for 4K editing? FCPX and plugins that interest me list 1GB as a requirement for 4K, so I'm wondering if 8GB VRAM is overkill....Is the hyperthreaded i7 required for relatively straightforward 4K editing (Canon XF-AVC Intra...though that's apt to change)? I've read anecdotal reports that recent i5 iMacs outperformed earlier i7's, so, again, is the i7 overkill?

There is no simple answer since video editing and codecs span a wide range. H264 1080p can be edited natively with good performance using either Premiere or FCPX on most machines. You don't need a top-end CPU or GPU for this.

OTOH most H264 4k codecs are difficult to edit, even on top-end machines, and often require transcoding to proxy for smoothest editing. Exceptions are H264 4k codecs like Canon's XF-AVC Intra, that is very fast to edit. There can also be a big difference between (say) Premiere and FCPX, especially on a Mac. In general FCPX is considerably more responsive, especially for editing H264 4k. It is about 4x faster exporting to H264 since it uses Quick Sync and Premiere does not. However Premiere has gotten faster the last year or so, even without proxy, which it now also has.

That's the editing; effects are different. No matter how lightweight the codec, a computationally-intensive effect must be calculated for each 4k frame. Effects can be implemented entirely in the CPU, entirely in the GPU or a mixture of both. Some effects like Neat Video allow CPU vs GPU rendering, a mix of both and how many CPU cores to use. 

In general 4k is really difficult to edit. From a CPU standpoint the more (and faster) cores the better. An i7 iMac can be significantly faster than an i5 iMac of the same generation because (1) the CPU clock is faster, and (2) hyperthreading. The current iMac 27 the i7 is about 11% faster just from clock speed. Benefit from hyperthreading varies widely. I used the 3rd party CPUSetter utility to disable/enable hyperthreading on an i7 iMac, and this made about 30% difference in FCPX export speed to H264. For other tasks such Lightroom import and preview generation, it made no difference.

Re Radeon 580, I haven't see any good benchmarks yet. However only certain tasks are amenable to GPU acceleration, e.g, H264 encode/decode cannot be meaningfully accelerated. The core algorithm is inherently sequential and not amenable to applying hundreds of lightweight GPU threads. But in general software developers increasingly try to leverage the GPU where possible. You can't update the GPU in an iMac so I'd tend to get the fastest one available.

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18 hours ago, Axel said:

There is huge difference now. Do you remember?

Now you can transcode in the background and start editing right away.

Whereas you can import all footage at once and immediately throw it into the timeline with FCP X now (even without transcoding, and, if you are fearless, even with naked files that are left in place!), it's not very smart. In my very humble opinion. This app offers us the best tools to prepare our clips for editing in the browser. In my eyes this is at least as crucial as the efficiency of the magnetic timeline. But I learned to respect the workflows of others. Mine also changes from time to time.

Oh Yes, I remember those days!

I do use FCPX & know all about transcoding in the background etc... It is a great NLE now, bit clunky to begin with, but now it has become better & better! Must mention that Motion is well worth a look too, especially since you can make your own Plugins for FCPX....

I'm very interested in getting back into AVID, which I believe has now become free for 1080p editing/exports - it is one of the professional standards & would really like to see how it stands up to FCPX (also really useful if you are serious about getting good/highend paid jobs).

@joema Really useful info here - really annoying that there doesn't seem to be a standard for 4K H264. Does 4K ProRes suffer from being slow or is it just the inferior codecs?

Lots to think about - the last piece of the puzzle is going to be which graphics card (always a week link down the line with Macs).

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23 hours ago, Bioskop.Inc said:

....really annoying that there doesn't seem to be a standard for 4K H264. Does 4K ProRes suffer from being slow or is it just the inferior codecs?

Although we loosely speak of H264 as a codec, it is actually a coding format. The codec is the specific software implementation which produces that coding format. E.g, x264 and DivX both are codecs which encode to the H264 format. Codecs which produce the H264 format are allowed to use varying levels of compression and bitrates. You would not want a single set of rigid encoding parameters for all H264 formats.

The codecs that produce H264 formats are not inferior, any more so than ProRes is inferior to raw video. Each have specific tradeoffs and advantages. Like H264, there are many variants of codecs that produce various ProRes formats: http://www.4kshooters.net/2015/01/26/choose-the-version-of-prores-best-suited-to-your-project/

Typically the variants of ProRes are less compressed and easier to edit. However they are also much larger. This decreases the CPU burden to decode/encode, but greatly increases the I/O burden and disk storage required. It is all a tradeoff. My documentary team can shoot one terabyte of 4k H264 per day. If we only used ProRes it would be 8x that large, so we are thankful H264 exists.

H264 does increase the computational burden to edit, just like H265 will increase this further. Fortunately computer hardware is getting faster, especially aided by fixed-function hardware accelerators like Quick Sync: https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video, AMD's VCE: https://en.wikipedia.org/wiki/Video_Coding_Engine and nVidia's NVENC: https://en.wikipedia.org/wiki/Nvidia_NVENC

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