PDW700 workflow
 

Just thinking about the possibility that the new PDW700 might be able to record to SxS and disc simultaneously. I think this would give the ideal workflow in shoots in remote areas. Yes, discs could be seen as a permanent archive medium but alternatively if you just wanted data storage you could shoot to both simultaneously on location, then transfer the SxS to a single drive. Once back at base copy the material from the drive to one or more backup drives, verify that it's there and safe, then re-use both the SxS cards and the discs. If there was a problem and the data ws corrupted somehow then you'd have the optical discs to save your skin. I think a lot of people find it hard to trust solid state media and a setup like this would set people's minds at ease.

Dear Steve,

You raise some interesting points.

Some feel that there is a confidence factor today, due to problems that some have experienced with solid-state media.

I fully believe the reported problems.


These problems break down, as I see it, into a few categories:

1. Problems with specific cameras or audio recording devices.

2. Problems with specific brands/types/vintages/quality levels of solid-state media.

3. Problems with counterfeit media.

4. Problems with quality media that has worn out or is longer reliable, but was once very reliable.



For Category 1, the devices that use solid-state media have to be properly designed.

This is not a trivial as it first appears. But once it is proven that a device works reliably with solid-state media, it should continue to do so.


For Category 2, the best parts from the top quality brands are far better than they were a few years ago.

In the early days of solid-state memory, there were problems with endurance, the wearing out of the memory cells, and the designs were not as robust as they are today.

All solid-state memory for professional uses should have "wear leveling" and should have error detection and correction circuitry built in.


For Category 3, regretfully a user of solid-state media must be very cautious to avoid counterfeit or low quality media.

Ebay has some interesting articles on how to spot counterfeit media.

Avoid purchasing memory products if the prices appear too good to be true. The counterfeiters generally attack the most widely known parts/brands.

Buying quality parts, at the going rate, from reputable vendors such as DVInfo.net's sponsors, is a good way to protect yourself.

The Flash XDR will have a built-in feature to test your Compact Flash memory to ensure that it is actually the correct memory size and performance. Some counterfeiters re-label low cost/low capacity/low performance parts as the premium high capacity media.


For Category 4, even today's best designed, highest quality media will wear out eventually.

The "wear leveling" feature of today's cards ensures that writes to "logical" memory addresses are written to different "physical" memory cells over time.

The FAT (File Allocation Table) on the media is usually written to far more often that other memory addresses. So, the actual writes are to different physical memory cells with the "wear leveling" feature. This avoids the problem of some memory cells wearing out while other cells in the memory are sitting idle.

Quality manufacturers specify the endurance of their parts.

We are lucky as recording video/audio is an ideal application for solid-state media. This is a far better application of solid-state memory than other applications that require a very high number of writes to the memory.

Today, for example, the endurance of quality media is well over 10,000 writes and an unlimited number of reads for each memory cell.

Recording 10,000 events/shoots/etc. is a lot of recording. Is there any videotape that can stand up to 10,000 recordings with an unlimited number of playbacks?

Summary:

In the design of the Flash XDR, we specifically wanted to overcome the perceived and actual reliability issues of solid-state media.

If one purchases quality media, especially if one purchases the recommended professional quality media, then one should have a reasonable level of confidence in their media.

For critical work, for safety, for backup, or for workflow reasons, one can create two “original masters” simultaneously using the Flash XDR.

Professional photographers have been using Compact Flash memory for years. Some can reliably state that they had a Compact Flash card that went bad over time, usually with some type of indication beforehand.

But, I feel confident to say that no one has had two professional level, quality Compact Flash cards fail simultaneously.

So, if one creates two “original masters” simultaneously using the Flash XDR, we feel that the risk of a failure or dropout is exceptionally low.

Absolutely right, but is it not more than a possibility? I thought there was news at NAB that an SxS recorder designed to fit on the PDW700 in a simialr way to the CF recorder and the S270 was coming?

Dan - I don't want to put words into Steves mouth, but I suspect one of the things that may cause a lack of trust is more to do with solid state WORKFLOW than hardware or media. The possibility of finger trouble after a gruelling day of filming, especially if coupled with factors of being in a remote area.

In such a case, filming straight to (cheap) discs and worrying about the next stage back at base has a lot to be said for it, and your archive takes care of itself. In other cases, a cameraman may need to film a shoot, and simply hand the material to the producer at the end. What's easier than tape or disc then?

But in other cases, solid state has a lot to be said for it, especially in quick turn round situations, absolutely no question.

I don't see either solid-state OR disc as being inherently superior to the other - they each have their pros and cons dependent on situation. What I do see is the desirability of being able to call on either or both as required.

The XDR then becomes an obvious competitor to whatever Sony propose for the 700 with SxS, with the advantages of much cheaper media and the option of higher bitrate recording, but the disadvantages of higher cost, size and weight. But what about a cut down version of the XDR? Keep the CF recording ability, but lose the encoder, HD-SDI abilities etc - for many users the 50Mbs signal will be more than good enough. A small cheap device able to record the same signal as put to disc - but onto CF, not SxS - could be just what's needed.

Well I have both a solid state camera (EX1) an Disc camera (F350). I have taken both of these to hell and back and they have both work 100% reliably from 24 degrees below freezing to searing desert heat, hurricanes, sand storms and 100% humidity. I have frozen both SxS cards and professional Discs into blocks of Ice and put the Disc through the dish washer. Even after that kind of abuse they still worked perfectly.

Now... I can see a situation where you might want to shoot to both SxS and Pro Discs to get the advantage of fast turn-around from the SxS cards plus an archival master from the Disc. But in terms of reliability it's probably overkill and the added complexity and extra things to worry about could end up negating the reliability benefits.

I used to use tape to shoot my weather extremes and every year I would get camera failures due to dust and humidity, tape shredding due to moisture and drop-outs caused by dust and dirt. Since switching to XDCAM over 2 years ago I have a 100% reliability record with over 1,000 hours shot.

I'm sure you're absolutely right Alister, I just know that producers in particular can be a little nervous when they've spent thousands of pounds on a shoot which cannot be repeated and trusting some invisible data on a drive somewhere! Good to know you tested the material to extremes though, gives us a lot of confidence.
Steve

Yes, but there are also situations where you may want to shoot to disc only, and other situations where solid state only makes more sense. In the past, XDCAM has suited the former, P2 the latter. Now, the PDW700 with the SxS recorder or an XDR allows you to have one camera and choose media as appropiate. And in some situations, yes, shooting to both simultaneously makes sense.

It's not the physical reliability of XDCAM disc, SxS, CF or P2 or whatever that's being questioned here, just a fear that after a long day, possibly in non-ideal conditions, finger trouble sets in - "Format?"...."Yes".......... "OH..*&$%!!?*.

One of the scenarios discussed at NAB was the ability to shoot simultaneously to both media, then pull the card and hand to producer while camera operator continued gathering more material.

This is good for news deadlines in the sense that someone can start working on the story even as additional material is still being acquired.

The question then becomes, "Why not just pop the disc and give to producer as you start on a new one". The answer being that an SxS card can be shoved directly into a newer vintage laptop while the disc would require a large, stand-alone deck or the U1 drive. Speed and portability is what I feel they were thinking about.

-gb-

But that's the beauty of the optical disc system, you never need to delete them or format them. Click the tab over as it comes out of the camera and it is write protected.

Sorry Alister, I may not have been very clear. The first paragraph was replying to you, the second to Steves last post (#5) and to what Dan said in his original reply. That in less than ideal conditions it's the solid state workflow that may lose confidence - not the hardware.

But what you say above is exactly why I think record to disc is the most appropiate thing to do on some occasions - on others it may be solid state, or both together. That's why I like the choice.

Dear David,

I believe that you were using the "Format...Yes" as only one example of what can go wrong.

While formatting a flash card is not desirable, if one uses one of the widely available "Unformat" utilities, the data can be recovered, if action is taken prior to writting more data to the flash card.


Other cases are more insidious, such as thinking that one transferred the data to your hard drive, but not actually doing so.

To be candid, solid-state media does require more diligence.

Losing the data on a Compact Flash card is similar to writing over a tape before the footage is captured.

I do believe that the advantages of solid-state media outnumber the disadvantages. I for one would love to eliminate dropouts.

I also believe that the use of solid-state media or not will be an individual (or company) decision. Some will adopt it, some will not.

Most definately, the point is that what people are concerned about is workflow, not the hardware matters you accurately outlined. I doubt anybody has much worry about a P2 or SxS card failing physically - but human error in the heat of the moment, having to free up space to continue working, is a different matter.
If the discussion was tape v solid state, then yes. But as this thread is "PDW700 workflow" then the options become disc, SxS, and CF if the XDR is used. All of these get over any drop out issue.
Well, a year or two back, when the choice for tapeless working was XDCAM disc or P2, period, then yes, you (or your company) had to go for one or the other. (Or sit on the fence and keep using tape.)

We come round full circle to Steves first post and what this thread is about - the PDW700 and possible workflows. Now, with an SxS adaptor or an XDR, it's no longer one or the other - use whichever is most appropriate on a job by job basis.

Dear David,

I agree with all of your points. Your points are well taken.



Using solid-state media it is best to not delete files and then record.

This will work if the unit is not near the limits of performance of the solid-state media. However, if it is, then deleting files (with the possible exception of the very last file), will cause a fragmented file structure, which will cause a reduction in write performance.

It is best to format the media, then record.


With the cost of Compact Flash at approximately $160 for 32 GB, it should become feasible to have enough memory on hand to avoid the situation of having to delete a file, on an emergency basis, to make room for more recording.

If I was faced with having to delete a file, then continue recording on an emergency basis, I would record at 50 Mb 4:2:2, which is not close to the limits of performance of the Transcend 32 GB Compact Flash cards. Alternatively, the Transcend 16 GB Compact Flash cards are significantly faster and sell for $240 a card.

I've just been filming a review of the 700 after testing it for a few days. The release version is missing a number of things, like 25p, but that will added in June with a firmware update. Freaked me out filming HD interlace, don't think I have done that before apart from on a z1!!

Nice build quality. Sexy camera (Is that wrong to say that?!)

The review will be up by the end of the week

I think sexy is a good word to describe the 700.

Not that it adds much to the discussion (shame on me), but I feel the F350 is pretty sexy in its own right.

-gb-