Anyone shot much 35 Mpbs on the 700?
 

Hi there. Just got my new PDW-700 today (ex F350 owner) and absolutely delighted with it!
Has anyone compared the difference of the footage between shooting 4:2:2 at 50 mpbs and 4:2:0 at 35 mpbs. I'd be interested to see how much difference you really noticed. Shooting at 35Mpbs would certainly make things a little easier when it came to file sizes and editing. the 50 Mpbs files are pretty large to throw around - and you'd get a little more on a disc.

Cheers, Sparky

50 mb/s has been deemed a happy medium by many broadcasters, less than that and you'd maybe get questions asked. I think if it's material that's going to have any future archival use then stick with 50 mb/s, you'll be on much safer ground.
As for editing, AFAIK 50 mb/s XDCam works no problem - I used it on a Macbook Pro with no problem - but I'm no editor.
Steve

My main client has standardized on XDCAM HD 4:2:0 35mbps. They have a bunch of F350s, F70 decks and nothing to read 4:2:2 50mbps so for them, I always shoot at 35mbps. They tell me the F800 looks quite better than their house 350s, that is somewhat reassuring... On the 700, I don't think you will see much less compression artifacts when shooting at 50mbps vs. 35mbps because the additional 15mbps in the 50mbps format is most likely spent on the higher chroma sampling. Also, 50mbps is a full 1920 HD raster vs. 1440 for the 35mbps so, bits and bytes go in processing those extra pixels as well. Bottom line, the 700 and F800 look fantastic at both bit rates. For high end post and chroma key, I'd shoot at 50mbps without hesitation, for general acquisition and if you want to save on discs and/or wnat to enjoy more record time, go for the 35mbps.

Thierry.

My experience is similar to Thierry's. The 35Mb/s footage from a 700 looks very slightly softer than 50Mb/s due to the small resolution drop but there are no extra artifacts visible in first generation footage. The 50Mb/s footage does seem to hold up very slightly better in post production, but it's not a deal breaker.

Certainly the 700 looks a lot cleaner and less electronic than the PDW-F350 range, even at 35Mb/s. As always image quality starts at the front of the camera chain with the lens, then the sensors followed by codec and recording medium. Start with good clean pictures and everything else in the chain has an easier job to do.

Cool Mark,
This is the direction I'm heading into but it could be the 800 that I'll get next year.
I shoot an a daliy basis with my F350 and love it.
I would like to hear from you the challenges and new and exciting things that you have found shooting with the 700.

Cheers

I think this has been a really interesting thread. My clients loved the F350 footage I shot, so shooting with the same compression, but with a 2/3 inch camera with a fantastic sensor, could be a really good way forward. The majority of my work is high end corporate work, were I edit the footage as well, so this could be ideal. I got a bit of a shock when I first saw the file sizes of the 50 Mpbs footage! Thanks for your input.

Sparky

You say "same compression", don't forget that because of the extra pixels and 422 the 700 has the same compression at 50 mb/s as the 350 at 35 mb/s. With both at 35 mb/s the 700 is a fair bit more compressed.
Steve

Nothing wrong with the 350s. These are great and reliable cameras. I still have two of those and love their lightweight and simplicity. The 700 and F800 are definetly faster cameras. They also have better latitude, smoother hightlights handling and a very sharp sensor. Also, the 422 color space is better for high-end grading and post processing.

T.

There is no difference at 35Mb/s because both the PDW-700 and PDW-F350 record at 1440x1080 4:2:0. Compression ratio is approx 16:1.

When shooting at 1920x1080 4:2:2 50Mb/s with a PDW 700 or 1920x1080 4:2:0 with an EX or PMW-350 the compression ratio is around 20:1

I stand corrected, thanks Alister.
Steve

Not so - 50Mbs not only gives 4:2:2 sampling, but much lower overall compression as well, but the reasons aren't obvious, you can't use simple logic.

With the 4:2:2 sytem there are 2 chroma samples for every 2 luminance samples, against 1 chroma sample for 2 luminance samples for 4:2:0. Hence 4 total samples for 4:2:2 v 3 total samples for 4:2:0, so an increase in raw data rate of 33%. So, simple logic then goes on to say that 1.33x 35Mbs is about 47Mbs, or close enough to 50Mbs that it must be the same compression.

Unfortunately, that logic is flawed for two reasons.

Firstly, it assumes that chrominance samples are coded with equal weighting to luminance - and that's not true in practice. The 35Mbs aren't allocated roughly 24Mbs to luminance, 12Mbs to chrominance as may be expected. The bitrate allocation is biased towards coding luminance, much less to chrominance, so doubling the number of chroma samples doesn't need the extra bitrate (another 12Mbs) you'd initially expect.

Secondly, the extra samples have a high correlation to the original chroma samples of the 4:2:0 system - you're effectively interleaving an extra 960x540 matrix in with the original, and it's obviously going to have a lot of similarities. A clever coder will exploit that redundancy easily - hence not need anything like twice the bandwidth for twice the number of chroma samples.

Of the extra 15Mbs between the two systems, a relatively small percentage goes towards 4:2:2, the bulk goes to lowering overall compression.

My head is about to explode. But a lot has been explained :-)

See http://pro.sony.com/bbsccms/assets/f...mats_Guide.pdf there is a full table of compression ratios and sample sizes at the very bottom of the document.

You will see that the compression ratios for EX (21:1) and 422 (20:1) are almost the same, only a 5% difference which I wouldn't call "much lower", rather a tiny bit lower. Simple logic can sometimes be correct and I stand by my statement that both are "around 20:1".

That's not true. The bit rate allocation is not biased to luminance as you suggest as the chroma is already being subsampled prior to encoding compared to the luma, to further subsample would mean the signal is no longer truly 4:2:0.

Again, further subsampling through coding would mean the signal cannot be claimed to be 4:2:2. The compression ratio remains the same, thus the bandwidth doubles. But the end result is a cleaner decode is possible for the same bit rate/compression ratio as you have more samples to work with. It's the reduced subsampling that may give the 4:2:2 cameras the edge over multiple generations.

So I stand by what I said, the compression ratios for the 4:2:2 cameras and EX cameras are pretty much the same. The ratio difference of 5% is very small indeed and in most situations it would be impossible to see, the contents of the image will make more difference to the final picture than the tiny ratio difference. This is one of the reasons why I believe that in the future the BBC will accept 35Mb/s 4:2:0 for HD broadcast. The BBC's argument that only 422 at 50Mb/s is robust enough to go through the entire production chain doesn't really hold water. Yes, 422 with it's extra chroma samples should give slightly fewer chroma artifacts but I think the reality is that the difference is so small that in the real world it will make little if any difference, especially as HD in the UK is currently broadcast at 1440x1080 4:2:0.

The interesting thing is the 16:1 ratio of the older 1440x1080 XDCAM HD cameras. This lower compression ratio suggests that this mode (which is also available on the new EX1R and PMW-350) may be more robust in post production. However I think that the subsampling (1440 as opposed to 1920) may erode any advantage that the lower compression ratio offers.

Mine too! Interesting though.
Steve

I think that's to read too much into that statement. It's quite true that the compression ratios are very similar in terms of simply "data in:data out", but wrong to assume that compression ratio uniquely defines quality, even within a single basic codec family. Most crucially, the same compression ratio will give different qualities for different image sizes, everything else equal.
You're misunderstanding what I'm saying. The chroma signals aren't further sub-sampled - they just get allocated a lower bitrate than may be expected.

Let's imagine a single frame, and let's say we want to code this as three separate frames corresponding to Y, U, and V, in Photoshop, say. The Y frame will have a resolution of 1920x1080, and each of the U, V frames will have a resolution of 960x540, if we assume 4:2:0. Let's further assume we have 150kB for the whole process. "Simple logic" would mean that we assign that data proportionate to no of pixels - 100kB to Y (2megapixels) and 25 kB each to U,V (0.5megapixels). But we don't need to do that - we could allocate 125kB to the Y frame, and 12.5kB each to the U,V frames. So in Photoshop terms, we code the Y frame with a quality of (say) 7, and the U,V frames with a quality setting of (say) 2.

Which is very similar to what happens with XDCAM.

Now, we can extend that to say we now have not 150kB to play with, but 200kB - 1.33x as much. We are going 4:2:2 - so our U,V frames each become 960x1080 or 1megapixel. Even if we then double the data allocated to each (to 25kB), that still allows us now 150kB in place of 125kB for the Y frame.

Try an experiment in Photoshop. Open a frame, then compress as a JPEG with a quality setting of 5. I've just done that, with a 1067x800 pixel image, and get a file size of 199kB. Now rescale vertically, to give a 1067x400 (squashed) image and do the same thing, same quality setting. "Simple logic" will suggest a file size of 100kB, won't it? In practice, when I do it, I get 118kB - about 20% more than theory would seem to suggest - so what's going on?

It's roughly what I was referring to when I said "Secondly, the extra samples have a high correlation to the original chroma samples of the 4:2:0 system ....." You don't need twice the number of bits to code twice the number of pixels *FOR THE SAME BASIC IMAGE*. You can take advantage of correlation, and it's the same for 4:2:0 to 4:2:2.

In my hypothetical example above, you don't need 2x12.5kB for the same quality - you can get away with less for the same compression quality. So you might be able to divert even more of the 200kB away to lessen the compression in the luminance image.
It's not really the BBCs argument, but rather that of the EBU after some very extensive and scientific trials. I don't think they actually rule 35Mbs 4:2:0 out, but rather only give a full thumbs up for general acquisition to 50Mbs. It's quite conceivable that broadcasters will decide that (if they go the Sony route) 50Mbs is de rigour for higher end programming, but 35Mbs is fine for news, sport etc - we'll have to wait and see.

It may be a comparable situation to the last ten years, when 4:2:2 and Digibeta were seen as most desirable - but DSR500s with 4:2:0 and DVCAM were seen as quite good enough for some types of programming. Actually had some advantages - cost and ease of integration with non-linear field editing.
The EBU recommendations are based on multiple generations (with pixel and frame shifts) and passage through the broadcast chain with decompressions and recompressions. Hopefully, I've convinced you now that the differences are much more than just more chroma samples (and yes, much of the benefit to be lost for final 4:2:0 transmission coding) but significant improvements in lower luminance compression.

At least you can put something like a nanoFlash on a PMW350 to get full approval. You can't put an external 2/3" chipset on an HPX301.

I think we need to go back to basics here.

A full resolution Y CbCr image is 4:4:4. Subsampling that image to 4:2:2 is a form of compression. Compression is, in it's simplest terms, taking a big thing and making it fit in a smaller space, whether that is through sub sampling, DCT, quantization or any other method, making a big signal smaller is compression.

4:2:2 is the ratio between the amount of data used to portray the Y (4) Cb (2) and Cr (2) signals. So if you use 8Mb/s for the Y then for it to be 4:2:2 you MUST use 4Mb/s for each of the Cb and Cr. If you use anything other than this ratio then it is not 4:2:2 but some other ratio.

The simplest way to achieve this is to use the same compression routine for each channel and simply reduce the sample size by a factor of 2 for Cb and Cr. This is very easy to do. Most 4:2:2 encoding schemes use one encoder to encode the Y and then a second similar encoder running the same coding routine but alternating between one sample of Cb followed by one sample of Cr. In fact a better way to describe this would be 2:1:1 as for every two luma bits of luma data there are one each of Cb and Cr. This gives us the familiar 4:2:2 encoding that we are all familiar with. The compression ratio is by default the same for each channel while the sample size is halved for each of Cb, Cr.

If you compress the chroma (Cb,Cr) by a different ratio than 2:1 then the ratio between Y and Cb, Cr is no longer 2:1 so you can no longer claim the system to be 4:2:2. While it is technically possible to compress the Cb and Cr at a different ratio to the Y channel this is not what is going on with XDCAM and is borne out by the maths.

4:2:2 = (1920x1080 + 960x1080 + 960x1080) x30(fps) x8 (bits) = 995Mb/s
4:2:0 = (1920x1080 + 960x1080) x30(fps) x8(bit) = 746Mb/s

If we divide 995Mb/s by 19.9 (the exact compression ratio given in the Sony document) we get 50Mb/s
If we do the same for 746Mb/s divided by 21.3 (again from Sony document) we get 35Mb/s

I don't think it is a mere coincidence that the maths works so exactly, more to do with the fact that the compression ratio is equal in each channel.


As I said, and on this we agree. Starting with more samples, ie. 422 over 420 should in theory at least give a marginally better end result however this will depend a lot on the quality of the decoder and the image content. In terms of visible artifacts these are most noticeable in the full resolution luma channel and with both XDCAM HD422 and EX this is compressed by pretty much the same amount so there will be little to no difference in most cases. In terms of concatenation there will be very little, if any difference between EX and XD HD422 material. Differences in scene content, lighting and camera settings such as detail, gain and aperture will make a much bigger difference than the difference between 4:2:0 @ 35Mb/s and 4:2:2 @ 50Mb/s. The BBC are currently enforcing the 50Mb/s rule yet don't stipulate gain or detail limits. In the past it was possible to get a dispensation for 35Mb/s with an EX, but last I heard the rules were being much more strictly enforced and it's all but impossible to get permission to use an EX, even for situations where shooting with a larger camera is just about impossible.

As you say it's easy enough to add a NanoFlash to an EX and record at 50Mb/s or better still 100Mb/s to comply with the rules, but to be honest the rules don't make a great deal of sense. The difference between 35Mb/s EX and 50Mb/s XD HD is very small from an artifacts and muti-generation performance point of view. A PDW-700 with a high detail setting or any gain switched in will produce an image that will fall apart quicker in a poor production chain that a well set up EX1. It is arguable that the ultra clean (59db) images from the PMW-350 will hold up better than the noisier pictures from the PDW-700 (54db). My belief is that the BBC have chosen to set the bar at 50Mb/s to prevent or restrict the use of small cameras as they are often operated by people that simply don't know how to use a camera properly in the name of "cost saving". What would make more sense would be to allow 35Mb/s while ensuring that productions use skilled and competent crews.

In the past programmes would be rejected for poor camerawork, dirty lenses and out of focus shots. These days it seems that provided it meets the correct technical specifications pretty much anything goes.

I don't know enough about the technicals to chime in regarding the 422 and 420 compression systems. However I do think that the BBC's rules are a little on the silly side. While they may be following the EBU recommendations they should be followed as such. As guidelines.

The trouble with putting a cast iron rule on the type of recording system and size of chips used is that there are barely any cameras that meet the spec!

The Panny 301 falls foul of the rules because of its 1/3" chips. All other large chip Panasonic cameras fail to meet the spec because they don't have full 1920x1080 sensors until you reach the 3000 series.

Of the Sony's you have to go to the 700 and 800 as far as out of the box systems go. It is all well and good that the BBC lay down the law, but they must be prepared to give budgets and pay that allow for people to meet those specifications.

I do think that the rules will be relaxed. Dear old Auntie only has one HD channel, bless her. But as soon as HD spreads more and they have more output they won't be able to use 50Mb/s min spec cameras all the time.

I think an assumption is being made here, and it's not valid. I agree with the basic numbers you quote above:
But let's look at them another way.

For 4:2:2, you can regard the 995Mbs as two separate streams of about 497.5Mbs - one for luminance, one for chrominance. It's possible to then deal with them in separate ways, and that's exactly what happens. But at no stage are the image sizes altered - they remain 1920x1080 (Y) or 960x1080 (U & V).

You are making the assumption that each stream is compressed according to the figure in the Sony document - 19.9 in this case - which implies that after compression we end up with two streams of about 24.9Mbs. Add them together, and hey presto, there's out 50Mbs XDCAM 422 signal.

But you don't need to apply the same compression ratio to each stream, any more than you need to apply the same compression ratio to two still photos. What if we choose 12.44 as the compression factor for luminance, and 49.75 for chrominance? That then gives us two streams post compression of 40Mbs and 10Mbs, add them together and we're back to 50Mbs. Obviously there's an infinite number of pairs of values for compression ratio which give the same total average - I don't know the real ones.

Practically, what this means is that the chrominance image is not just softer than luminance (because of sub-sampling), but will have higher artifacting as well (because of the higher compression ratio).

You can actually see the results of this on broadcast digital TV on low bitrate channels. One effect of a codec breaking down is a smooth gradient taking on a stepped or contoured appearance, and you may have noticed that the effect tends to occur far more on highly coloured gradients than lightly coloured ones. This is a direct result of using a higher compression factor for chrominance than luminance.
No, no co-incidence, but the 19.9 and 21.3 are just averages of input/output data rates using the lum/chrom streams totalled in each case. They don't tell you anything about what's happening individually to luminance compared to chrominance.

A bit like looking at traffic accident statistics. You might be told there are 50 per 100,000 of the population - but that tells you nothing about relative figures for old/young drivers etc.

Let's compare XDCAM EX at 35Mbs to HDV. They are both 4:2:0 systems, but the former is based on 1920x1080, the latter on 1440x1080. If we accept your logic, then to increase the number of pixels from 1440 to 1920 is an increase of 33%. If we apply that pro rata to post compression data rates, we need to increase the 25Mbs by 33% - about 8.5Mbs - to get about 33.5Mbs. So wouldn't you then expect the overall quality of the 35Mbs codec to be about the same as HDV, albeit with a higher horizontal resolution?

In practice, that's not the case - XDCAM EX is substantially better than HDV - and a large reason for that is that you can't simply say "33% more pixels means a 33% increase in coded data rate for the same compression quality". As I've been saying all along.
Well, not just the BBC, it's an EBU wide recommendation, and followed by others outside Europe. My own feeling is that here it would make the most sense for the manufacturers to put a 50Mbs mode on the camera than for the broadcasters to relax their preferences. I can't believe it would be technically difficult or expensive, (given the total price of the nanoFlash) far more likely an attempt to force the users to pay more than is really necessary - buy the next model up.

It could be a dangerous game if another manufacturer suddenly came out with a comparable camera that ticked all the boxes. In the meantime, it must be making Convergent Design very happy. :-)

In one way yes. But in another Sony could for example release another model that does 100Mb/s and make the 700 a base model.

I think in some respects the 700 has been the victim of the current financial situation. The prices for equipment are now going up again (telling this to people like Producers and Michael Rosenblum however falls on deaf ears). Otherwise it might be possible for the 350 to take over from the DSR series (as intended) and the 700 to take over from the old PDW-350.

Never did get an answer as to why they named the new camera a 350, since people generally just say "350". Now I don't know if they are talking about the disc camera or the SxS camera!

I guess rather than speculating or hypothesizing the simplest thing to do would be to analyze the streams from an EX and a PDW-700 and see what's actually going on.

Anyone know a good utility that will show the separate Y CbCr bitrates.

However you look at it the compression ratios are remarkably similar and my multi-generation test which is made up of 5 passes using the native codec and shrinking and shifting then stretching and centering the image on each pass gives almost identical results on both XDCAM HD422 and EX. Given this is an unrealistic workflow anyway and a more robust codec should be used through multi-generation post, prores HQ or DNxHD for example, I stand by my claim that there is little to no difference in the robustness of the two formats and that noise/grain and picture content will have a greater bearing on the final image.

Not everyone is following the EBU recommendations and I know there are several influential people within the BBC trying to get acceptance for the EX and in particular the PMW-350. I've seen plenty of my EX material in big budget HD broadcasts alongside HDCAM and it's never looked in any way sub standard. Lost Land of the Volcano was shot using EX's and PDW-700 and I bet no one could tell which was which in the finished programme. Well.... apart from when one of the EX's melted going in to the Volcano.

I'm not saying EX is a replacement for PDW, for a start the workflows are very different. But from the point of view of image degradation through a typical end to end production chain I really don't think there is any significant difference between the two. In fact that's why I like to shoot at 100Mb/s with my NanoFlashes, because at 100Mb/s I am seeing real benefits with both.

Yes, I'd love to know the answer. My understanding is that the chroma is definitely being compressed by a different factor to luminance - but I don't know by how much.
I feel you are equating compression ratio (data rate in:data rate out) to compression quality, and even within a given codec I don't believe that's a valid assumption. How well an image compresses is due far less to how many pixels make up the image, but how much information it contains - using the word in the scientific sense. Hence, a 960x1080 image which is uniform blue for the top half, red for the bottom could theoretically be perfectly compressed into only a few bytes.

For a more realistic image, start off with a 960x1080 monochrome image (such as for 4:2:2 U or V), then scale to 960x540 (to simulate 4:2:0). Now scale back up to 960x1080. Information (vertical resolution) must have been lost in the process, but the rescaling will have interpolated the missing lines as well as it can.

Comparing this with the original 960x1080 shows how much INFORMATION got lost in the first downscaling process, as opposed to pixel sites. You're obviously going to lose half the pixel sites, but much less than half the information, and this is what is important to a coder. It exploits that any given pixel in a real image is likely to generally have a very similar value to it's neighbours - it's exploiting REDUNDANCY in the chroma signal. It's why you don't need twice the number of bits to code twice as many pixels.

Now all that is why I think any statement like "all 50Mbs gives you is 4:2:2" is a fallacy, albeit an oft-quoted one. But coming back to the real world, the question is "well OK, but even so, does it matter?" And hence on to the other points you and Simon bring up. (And which, by and large, I have a lot of agreement with.)

There may well be an argument for getting such as the BBC to accept the PMW350 as it stands - but then I can see a much bigger argument in getting Sony to upgrade it to 422 50Mbs. (Which I'm sure is technically possible at not much extra cost.) At which point all acceptance arguments disappear into the sunset.

My feeling is that the 350 will get a sister model with 50Mb/s. XDCAM camcorders usually come in pairs (510-530, 330-350, 335-355, 700-800). A 50Mb/s version of the 350 wouldn't encroach on any other of the Sony camcorders.

Any such model would be closer to the 700 in pricing (or halfway between 350 and 700). But it wouldn't impact on the 700 because some simply want the disc workflow instead of solid state. Furthermore the performance of the 350 as it already stands, plus the use of a NanoFlash, means that if the 350 was to encroach and impact on the 700 then it has done already. So it could make sense for Sony to offer a model with 50Mb/s recording for a couple of grand more to save owners from putting an external device onto it. Something that they would do anyway even if there wasn't a sister model.

I doubt we will see a 50Mb/s PMW-350. It would compete directly with the 700 and Sony like to have distinct product lines in distinct markets. As I see it:

EX1/EX3 replaces DSR300 budget 1/2" DVCAM for low cost corporate.
PMW-350 replaces DSR-450/DSR570 for news and corporate sector.
PDW-700/F800 replaces Digibeta for general broadcast.

Certainly many people will prefer the optical disc workflow over solid state but many people, myself included bought in to XDCAM HD422 primarily because it is accepted for broadcast out of the box, pretty much universally. There are many PDW users desparately waiting for Sony to release the SxS adapter so they can switch to solid state. Lots of rumors as to what that will do, 50Mb/s maybe more?? it will almost certainly have HDSDi in.

...and I think that like DVCAM vs Digibeta, 2/3" XDCAM will become used for a huge number of broadcast shows, including primetime.

The nano flash is an interesting curve ball in the mix as well.

I guess we'll have to wait and see.

I tend to agree more with Simon. The above may be true as far as the first sentence goes (PMW350 for news and higher end corporate), but broadcasters are increasingly looking towards solid state for all acquisition. The 700/800 will be some peoples preference for a while to come, but increasingly I see people wanting XDCAM422 (or equivalent codec) natively in a solid state camera. I just don't see having to choose between solid state OR XDCAM422 a good sales ploy for long.

I also find it strange that Sony have considerably upgraded the EX1 - but not the EX3. My guess is there are more announcements to come, either upgrading the EX3, or discontinuing it in favour of a completely new model more nearly half way between the EX1R and the PMW350.

I disagree with that. When you look at pairs of cameras, they usually both have the same basic recording formats. What you get for a little extra $$ is bells and whistles and not a totally different HD recording mode. If there ever is a PMW-355, I predict it will only have a few extra features not found on the 350.

Perhaps a PMW-400 with 50Mb/s is more likely, but don't bet on that either.
I do agree that an EX3R or totally new camera must be in the works because there is a big gaping whole in the product line.

I've been told there are no plans for an EX3R in the near future and that the EX1R was introduced (in part) as a companion camera for the PMW-350 to give SD users of the 350 a solid state SD "B" camera that uses the same workflow.

But then I see Bob Ott saying that there are some surprises to come at NAB.

Question is: Will the SXS cards have enough (writing) transfer speed (50mbit/s + headroom for safety or overcranking) to make a 50mbit recording?

There is a SXS recording unit for pdw700 in the line - but nobody knows exactly, if 50mbit recording is supported...

Uli

As I see it, there are effectively three options:

1/ Upgrade the EX3 in a similar way to the EX1.
2/ Do nothing - keep the range as EX1R, EX3, and PMW350.
3/ Discontinue the EX3, and replace it with a new model - maybe a shouldermount 1/2" SxS - cheaper than the PMW350.

You rule out option 1, and I don't think option 2 is sustainable in a marketing sense. How can anyone charge more for a "higher spec" model, when the one below it has a lot of desirable features it's missing?

Hence my money must strongly be on option 3.

I'm still placing my bet on #1.
It's mostly software that needs to be upgraded. How hard can that be when the EX1R already exists?

Everybody has their own favourite out of all the improvements that the revision has brought, but two of the favourites are cache record and native SD capability. AFAIK they both need enhanced hardware. Maybe others like "dub all clips" could indeed be added via firmware.

But anyway, Alister's told us that no plans exist for an upgrade. It then becomes a question of what you count as an "upgrade", and what as a new model, discontinuing the old one. We'll see.