MiniDV or DVD ? 2

[kwunder]

Hi there

Just about to upgrade my digital camcorder. I have a Panasonic that is MiniDV but has been nothing but trouble since I brought it new with audio dropout etc. I have two choices in mind at the moment, but not sure which to go for. One is again MiniDV format and the othere is DVDformat. I notice also that the DVD model is not firewire enabled (like my old one) but has USB connectivity. Is this as good as firewire for transferring footage from Cam to PC ?
The 2 I'm looking at are these :-
SONY DCR-PC1000

http://www.sony.co.uk/view/ShowProd...w_en_GB&pageType=Overview&category=CAM+MiniDV

and
SONY DCR-DVD403

http://www.sony.co.uk/view/ShowProd...B&pageType=Overview&category=CAM+DVD+Handycam

Can anyone advise ?

Cheers

 

[cdogg]

Not sure about the other specs (I didn't look at em), but USB performance for transferring video would depend on whether it is USB 1.1 or USB 2.0. USB 2.0 is actually a tad faster than firewire. USB 1.1 would be unbearable.

And even if the device is USB 2.0, you need to make sure your PC has it too...

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[kwunder]

Cheers for that

It doesn't say on the Sony site if it is USB 1.1 or 2

Is there any difference in quality from MiniDV to DVD ?

Does the DVD used in the DVD Cam work in my conventional DVD writer on my PC ? If so, presumably it does away with the need to "transfer" the video footage as I'd be able to work with what is on the DVD ??

 

[felixc]

I think that the type of disc used in the cameras is DVD-Ram. This is not compatible with the regular DVD drives found in PCs. However there are some that do support DVD-Ram.

The Mini-DV is not compressed, that is it does not make use of compression techniques to fit more data on the tape, as the DVD format does. So if you are interested in the maximum quality possible, in theory the MiniDV format has a better image quality in particular in scenes where there are many movements. However, if you don't mind to see movements artifacts like those that you may sometimes see on DVD movies, then you may prefer to have the DVD camcorder. I suggest that you search for reviews on the net for the models that you are looking for. Issues like MiniDV vs DVD are usually less important than others like color fidelity, response time, and low-light image quality.

Firewire or USB2.0. Unless you want to use your camcorder as a live video device for capture or viewing on your PC, you won't notice the difference. Firewire has the "real-time" video right in its specs. This is not the case with USB2.0.

 

[kwunder]

Thanks felixc

I did do a search for product reviews and tests and discovered

http://www.camcorderinfo.com.

It is a bit eavy giong but generally, if you wade through to the end of the review, you get a summary, which is enough to go on.

Thanks again

 

[micker377]

Just a note:
read today (

http://www.realtechnews.com/posts/1900)

where Sony is not pushing Mini-DVD's - there is talk about discontinuing them. They are looking to high capacity flash memory to replace it.

 

[kiddpete]

I have seen many people report problems with USB transfers. Firewire is vastly preferred for video transfer.

 

[cdogg]

Just to clarify micker, the "Mini-Disc" format is for audio only.

When it comes to video, Sony uses Digital 8 (on older camcorders) and Mini-DV (on newer camcorders). Mini-DV is not synonymous with "Mini-Disc". You're talking about two different things.

Also, flash memory is just fast enough to transfer highly compressed audio, such as MP3 or WMA formats. It is not anywhere close to being fast enough for video transfers, which is why you don't see it used in camcorders. You'll find flash memory's most common use in Digital Cameras, iPods, etc...

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[felixc]

To further clarify, the Mini-DVDs used in the DVD camcorders are not threatened.
There are camcorders that just use flash memory as the storage medium. This may be a trend for the future, as the capacities of CompactFlash and others are already exceeding 4 gigs. Some others, JVC I think, have an internal hard disk which is also interesting (maybe not for vibrations though) because of an instant response to the "record" button. These new media are not necessarily giving a better image, so you have to weigh the techno fuzz against costa and common sense.

 

[cdogg]

Felixc,
Flash memory shouldn't be fast enough for a camcorder. Any idea where you saw one of these babies for sale? I'd be interested in seeing one...

Now, I have seen some camcorders use both Mini-DV and flash memory together, but the flash memory was only there for storing still images. Other camcorders I've seen use the IBM Microdrive that you mentioned. But I have yet to see an all-flash-memory camcorder.

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[felixc]

Can't recall if it was Sharp or another brand. Not a high-end model. If the data is stored as mpeg-2, the bandwidth required isn't that big. Memory sticks and SD cards are using serial protocols that aer slow. But the flash chips themselves are parallel devices, so integrated memory is by default much quicker than any packaged format that requires a protocol.

I have a CompactFlash Microdrive in one of my systems. It is not a quick device.

 

[micker377]

Thanks for clearing up the mini-disk/miniDV for me. That's why Im here - to help, and to LEARN.

 

[cdogg]

But the flash chips themselves are parallel devices, so integrated memory is by default much quicker than any packaged format that requires a protocol

felix,

I just want to point out here that the fastest flash memory on the "consumer-end" market cannot write faster than 5MB/s. Most average around 1-2 MB/s. At that rate, it is way too slow for even MPEG-2 video, unless the video is highly compressed making it unbearable for any camcorder owner.

This site might give more insight on speed and technology of flash memory:

http://www.robgalbraith.com/bins/multi_page.asp?cid=6007

Also remember that the term "microdrive" often refers to a miniature hard drive that rotates. You usually don't refer to flash memory as microdrives.



I've been following this arena for some time now, and I don't believe that flash memory is ever going to be fast enough for high-quality video. There are many other newer technologies on the horizon, made of different compounds but using the same basic technology as flash, non-volatile memory. The difference? Much, much faster than anything you see today. Until then, camcorders however will continue to use good old tape or mini-DVD's.

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[felixc]

Hi cdogg,

just to keep the discussion open

http://www.sandisk.com/retail/ext3-cf.asp

And this is a retail/consumer. Internal flash does not add the bandwidth limitations of the protocols found in these memory cards, so it can go even faster. (In a previous life I have designed video frame grabbers.)

Considering that an mpeg-2 file at 6mbit/s gives a very good quality of video, I think that the technology is already there. You're right, other faster memory technologies are coming too, so the all solid-state camcorders may be the trend of the future.

Felixc

 

[cdogg]

Certainly, this discussion is "wide" open

felix,
Yes, I imagined that the 5MB/s barrier had been broken by now. But the vast majority of cards out there are nowhere near those stats.

The technology is there, I agree with you on that one. It will only get better over time. However, consider this:

Limitations

One limitation of flash memory is that while it can be read or programmed a byte or a word at a time in a random access fashion, it must be erased a "block" at a time. Starting with a freshly erased block, any byte within that block can be programmed. However, once a byte has been programmed, it cannot be changed again until the entire block is erased. In other words, flash memory (specifically NOR flash) offers random-access read and programming operations, but cannot offer random-access rewrite or erase operations. When compared to a hard disk drive, a further limitation is the fact that flash memory has a finite number of erase-write cycles, so that care has to be taken when moving hard-drive based applications, such as operating systems, to flash-memory based devices such as CompactFlash. This effect is partially offset by some chip firmware or filesystem drivers by counting the writes and dynamically remapping the blocks in order to spread the write operations between the sectors, or by write verification and remapping to spare sectors in case of write failure.

...

The cost per byte of flash memory remains significantly higher than the corresponding cost of a hard disk drive, and that (on top of finite number of erase-write cycles previously mentioned) has prevented flash from becoming a solid state replacement for the hard disk drive on normal desktop and laptop computers.

While it is certainly possible to construct a camcorder that uses only flash memory, the complexity and cost may be too much in the near future for it to be profitable or catch on. So far, I haven't seen one for sale. You can bet that when one hits retail, I will be right there to read the review!


Also note that when recording video on an empty flash module, it should work fine because it's writing sequentially. But as soon as you do some editing (like recording over a previous scene), now you've got data scattered in blocks all over the card. Random read, write and erase is where flash falls below acceptable performance.

Microdrives and a combination of flash may be the only way to go until better technology hits the scene...

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[felixc]

I just googled "flash camcorder".

Here's one, and not a cheap one!

http://www.camcorderinfo.com/content/panasonic-p2-flash-pro-04_18_04.htm

Here's the one that I saw in the local ads. I remember the odd shape:

http://www.camcorderinfo.com/conten...-Camcorder-with-4-Megapixel-Sensor-VPC-C4.htm

It even works with the slow SD modules! And I mean slow! Okay this is mpeg-4 but with a direct CCD input, the results might be surprising.

If you can't beat them, join'em!

What wikipedia describes is only one type of flash technology. I use similar flash chips on one of my products. Products like the camcorders will use RAM to work around the "block erase" if they want to use these cheap flash chips. There are flash parts that do support byte erase. But video is sequential anyway, so these concerns are just one of many in a big cost vs real estate and feasibility equation when we design these things.

Felixc

 

[cdogg]

OK, I'll hand it to you that there are some available I wasn't aware of (though I'm not too surprised, I suppose). The Panasonic P2 even has caught on big with many mainstream companies such as COX publishing.

Definitely a lot of interesting facts to chew on in this thread. As you said earlier, Felix, flash memory that is integrated as a "solid-state" hard drive is much, much faster than a memory card that has to rely on protocols. I guess that's the real difference here that I wasn't focusing on before.



~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884