Q. Its a Panasonic PV-GS31 camcorder.
A. You need to know what AMPERAGE - milliamps the Camcorder is rated for at the 7.9 listed voltage. Adapters almost NEVER give the voltage that the label indicates - if you have a digital multimeter and look at the voltage, you will usually find that 7.9 volts actually reads 14 or 16 volts with no "load" ( not plugged in ) as the camcorder uses power the
voltage will drop, and the Amperage will increase - different
functions on the camcorder such as rewind, zoom, playback etc. will use different motors and chips, and therefore use different amounts of power. Some adapters use cheap
single diode converters from AC ( Alternating current input of 120 volts, which goes from zero to 167 vots in one direction, back to zero, then to 167 volts in the other direction, and back to Zero ) If there is little or no CAPACITOR value in MicroFarads, then the output is a choppy
jagged pulse. The Output rating of 7.9 volts at xxx milliamps ( one thousand milliamps is one amp ) is an AVERAGE only - at one specific amperage listed !
NOTE - you also need to know the center tip and outer
adapter plug poarity ( Positive and negative ) of the
replacement 7.5 volt adapter ! ! ! make certain that the
positive and negative match the required 7.9 volt inputs.
If you use a 3 AMP ( 3000 milliamp ) 7.5 volt adapter,
it may work much better than a 1100 milliamp 7.9 volt
adapter, since when the Camcorder uses a lot of power, the
7.9 volt may drop to 7.3 volts under heavy load, but the
7.5 volt ( "RATED" ) adapter may actually put out
9 raw volts, and NEVER drop below 7.5 volts with the
3000 milliamp ( "power output " ) it is capable of supplying. Unless I find a computer grade switch mode power supply rated a 5.0 volts, xxx amps, I rarely find any
adapter that actually puts out the VOLTAGE that is listed
on the label. Ten different adapters, by ten different
companies, all with the same output label ( 7.5 volts at
1000 milliamps ), will actually give 10 different voltages
at any given load ( Current draw in milliamps ).
Just make certain that the polarity ( Positive and negative ) is correct, and try the 7.5 - if the adapter gets too hot in a few minutes of use, then it is too small in its Amperage output, and you could burn it out. If it has an equal, or higher amperage than the original 7.9 adapter, and it remains cool running, and the camcorder works perfectly, then you are probably ok.
Summary - check the polarity and the amperage required. If your 7.5 volt adapter is labelled 200 or 450 milliamps then you are probably in trouble - the adapter is for a tiny device that uses little power. If the camcorder label states
1.6 amps ( at 7.9, or " 8 " volts ) then you are better off to try to find an adapter with similar or HIGHER amperage output, at, or near 7.5 to 8 volts, for example 2 amps ( 2000 milliamps ). If you had 2 electrical meters, one set to amperage, the other set to votlage, you could see the actual voltage of any adapter drop from, for example, 12 vots raw output, with no load, to 7.9 volts under heavy camcorder load when plugged in.
NOTE 120 Vots is not 120 volts of anything - it is an AVERAGE of the curve going up and down from zero to about 167 vots at the peak of each "hill" in the center. The wave form of 120 volts looks like a bunch of hills, alternating
with identical valleys, so the average "real" power is
about 120. If you look at an oscilloscope you see a sine wave, which looks like the side view of ripples in water.
If you had to say how high the water level was, and there were waves comming in on the beach, you take the average between the tops of the waves and the bottoms, and use that as an average. Similar to "120" volts, or 7.9 volts Direct current ( Direct Current is exactly the same a a battrey output - just a single voltage with no waves - just a straight line, like a water level on a day with no wind - flat ) Most adapters put out some form of ripple or waves caused by the 120 volt input's huge waves.
So, 7.5 and 7.9 "could" be almost identical, depending on
how well the adapters were made, and what electronics were used inside the adapters to change 120 volts down to " 7.9 ".
FINALLY, if I haven't bored you to death already, the CAMCORDER itself usually has a power regulation circuit
built into it as well ... This means that the Camcorder takes in the raw "7.9 volts" and has circuits to change the power to charge the camcorder's batteries ( high current, probably about 6 volts ), to run the motors ( probably
various tiny motors running 6 volts, 5 volts, 3 volts etc
depending on how powerful they need to be ), to run the memory and controller chips, (5.00 volts, 3.3 volts, 1.5 volts, etc. ) and to supply the mini liquid TV viewer screen's backlight... SO... This means that even a 9 volt
power supply with a correct polarity, and similar Amperage rating may work just fine, IFF the power converter circuits in the Camcorder itself can handle dropping a bit of excess voltage from the 9.0 volts ( rated, but putting out 12 vots raw power easily under no load ) to 8.0 ( or 7.9 ) volts rated by the Camcorder manufacturer. Again Amperage rating is a huge factor to consider...
Hope this helps
ROBIN
voltage will drop, and the Amperage will increase - different
functions on the camcorder such as rewind, zoom, playback etc. will use different motors and chips, and therefore use different amounts of power. Some adapters use cheap
single diode converters from AC ( Alternating current input of 120 volts, which goes from zero to 167 vots in one direction, back to zero, then to 167 volts in the other direction, and back to Zero ) If there is little or no CAPACITOR value in MicroFarads, then the output is a choppy
jagged pulse. The Output rating of 7.9 volts at xxx milliamps ( one thousand milliamps is one amp ) is an AVERAGE only - at one specific amperage listed !
NOTE - you also need to know the center tip and outer
adapter plug poarity ( Positive and negative ) of the
replacement 7.5 volt adapter ! ! ! make certain that the
positive and negative match the required 7.9 volt inputs.
If you use a 3 AMP ( 3000 milliamp ) 7.5 volt adapter,
it may work much better than a 1100 milliamp 7.9 volt
adapter, since when the Camcorder uses a lot of power, the
7.9 volt may drop to 7.3 volts under heavy load, but the
7.5 volt ( "RATED" ) adapter may actually put out
9 raw volts, and NEVER drop below 7.5 volts with the
3000 milliamp ( "power output " ) it is capable of supplying. Unless I find a computer grade switch mode power supply rated a 5.0 volts, xxx amps, I rarely find any
adapter that actually puts out the VOLTAGE that is listed
on the label. Ten different adapters, by ten different
companies, all with the same output label ( 7.5 volts at
1000 milliamps ), will actually give 10 different voltages
at any given load ( Current draw in milliamps ).
Just make certain that the polarity ( Positive and negative ) is correct, and try the 7.5 - if the adapter gets too hot in a few minutes of use, then it is too small in its Amperage output, and you could burn it out. If it has an equal, or higher amperage than the original 7.9 adapter, and it remains cool running, and the camcorder works perfectly, then you are probably ok.
Summary - check the polarity and the amperage required. If your 7.5 volt adapter is labelled 200 or 450 milliamps then you are probably in trouble - the adapter is for a tiny device that uses little power. If the camcorder label states
1.6 amps ( at 7.9, or " 8 " volts ) then you are better off to try to find an adapter with similar or HIGHER amperage output, at, or near 7.5 to 8 volts, for example 2 amps ( 2000 milliamps ). If you had 2 electrical meters, one set to amperage, the other set to votlage, you could see the actual voltage of any adapter drop from, for example, 12 vots raw output, with no load, to 7.9 volts under heavy camcorder load when plugged in.
NOTE 120 Vots is not 120 volts of anything - it is an AVERAGE of the curve going up and down from zero to about 167 vots at the peak of each "hill" in the center. The wave form of 120 volts looks like a bunch of hills, alternating
with identical valleys, so the average "real" power is
about 120. If you look at an oscilloscope you see a sine wave, which looks like the side view of ripples in water.
If you had to say how high the water level was, and there were waves comming in on the beach, you take the average between the tops of the waves and the bottoms, and use that as an average. Similar to "120" volts, or 7.9 volts Direct current ( Direct Current is exactly the same a a battrey output - just a single voltage with no waves - just a straight line, like a water level on a day with no wind - flat ) Most adapters put out some form of ripple or waves caused by the 120 volt input's huge waves.
So, 7.5 and 7.9 "could" be almost identical, depending on
how well the adapters were made, and what electronics were used inside the adapters to change 120 volts down to " 7.9 ".
FINALLY, if I haven't bored you to death already, the CAMCORDER itself usually has a power regulation circuit
built into it as well ... This means that the Camcorder takes in the raw "7.9 volts" and has circuits to change the power to charge the camcorder's batteries ( high current, probably about 6 volts ), to run the motors ( probably
various tiny motors running 6 volts, 5 volts, 3 volts etc
depending on how powerful they need to be ), to run the memory and controller chips, (5.00 volts, 3.3 volts, 1.5 volts, etc. ) and to supply the mini liquid TV viewer screen's backlight... SO... This means that even a 9 volt
power supply with a correct polarity, and similar Amperage rating may work just fine, IFF the power converter circuits in the Camcorder itself can handle dropping a bit of excess voltage from the 9.0 volts ( rated, but putting out 12 vots raw power easily under no load ) to 8.0 ( or 7.9 ) volts rated by the Camcorder manufacturer. Again Amperage rating is a huge factor to consider...
Hope this helps
ROBIN
Best consumer camcorder?
Q. I want to buy a new camcorder. I prefer Canon, but might consider something else. I usually videotape fire scenes for our local dept, and i film trains some. I would probably be doing some indoor shoots too, such as a school Christmas play. Here is what i'm looking for:
* Preferably under 600$
* I want to attach a shotgun mic to it (such as RODE videomic)
* I may want to add a led light for shooting also.
* Preferably under 600$
* I want to attach a shotgun mic to it (such as RODE videomic)
* I may want to add a led light for shooting also.
A. his wahat I was told :
The problem with HD is that it is not a video standard, rather it is a marketing term that describes a frame size only (i.e Full HD is 1920 x 1080).
The quality varies widely, and cameras run from under $100 to over $100,000 (not a typo). Along with normal camera parts and pieces such as lens quality and light gathering, the quality is also dependent on the data-rate, the LESS time you can record on a given size card or hdd, the better the video.
The final nail in HDs quality coffin is the compression. Only a fraction of the 25 or 30 frames per second are from light processed by the sensor. In some cameras MOST of the frames are mathematically calculated based on frames ahead and behind.
So, before the merits of SD, the limits of HD...
Really cheap cameras will get 6 or under gb of data per hour.
Name brand, cheap cameras typically get 8 gigs/hr
About $350 or so, the consumer twinkie cams get 11 gigs/hr. This does not change even into the top of the line, $2000, consumer twinkie-cams.
DSLRs get 20 gigs and approach very good quality, but they do have a host of other issues that make them ill suited for recording long events like a wedding. All over the web and here on "Answers".
Pro cameras start at $3000 and get 25 gigs/hr HOWEVER the compression has improved to 4:2:2 intraframe compression, no frame depends on its neighbors. Quality and cost go way up from here.
SD, MiniDv based cameras for consumers are few new, Canon stopped their last one in January, the ZR960. But this format is still popular for pros and TV field use. Remember this frame size is 1/6th that of HD, yet it gets 13 gigs/hr of data and is 4:2:2 compression. In other words, very good quality.
Your problem is that your fellow consumers gave up quality for ease of use. Your only options now, unless you can find unsold DV cameras, is to go with a used camera or spend the $800 or more to get a HDV camera. (HD version of MiniDv, 1440 x 1080 typically).
The other issue is that for consumers, DV and HDV is actually MORE data intensive than HD for storage (The tapes are a built in archive, though) and editing. You will need a firewire port on your computer.
HD from ANY twinkie camera is fine for small screens, computers, phones, youtube. But even on a moderate HDTV it starts to fail in quality. My SD, Canon GL-2's video can be up-converted to HD and is better than native HD the small consumer cameras.
If you can find on, DV will give you better video in more environments. DSLR may be an option, just know their limits. HDV is very good and the best you can get under $1000 new.
Just depends on budget, specific uses and your intended media...
Scott's answer is spot on, but there's still the issue of editing. As Scott said, the HD formats throw away most of the video data - this is fine for the finished product (Blu-ray, DVD) but not good for editing. Most of the frames you want to edit have to be reconstructed on the fly - this needs a lot of computer power. Another problem is that every change you make is likely to degrade the video quality - if your business is providing good quality video, can you afford to do that? Then there's the final render - this will almost certainly be to a lossy format - this has to involve some loss of quality but it's worse if you're starting with a lossy format.
Someone said that cards are easier for editing - the only thing that's easier is the ability to put the card in a reader - it's a very slim advantage!
new is not the same as better. so the real question depends on whether you need "better" because of intended commercial use, or "newer" because its just for home hobby use.
The reason miniDV can be edited by all computer editors, including the freebie ones, is because it is open source code and has not been messed with for over 15 years. yep, a Windows95 could edit miniDV. further, its low compression of 6:1 greatly reduced the computational power demanded of the CPU to keep up in real time. Contrast that with AVCHD which is a proprietary secret invented by Sony and only available to editing programs that are willing to pay exorbitant license fees. That is why it doesn't come as a freebie. And the code is not fixed, AVCHD has undergone significant changes every year since being introduced, moving from a lousy 200:1 compression to a somewhat respectable 40:1 compression in current top level consumer cameras. So if you buy a discounted older model editor, it might not work at all with a new camera. AVCHD was designed by Sony to be strictly amateur grade, Sony designed XDcam for professional use and the differences are not trivial.
IMHO miniDV will continue to be a viable commercial format as long as movie DVDs remain as the primary distribution media. not everybody wants to view videos on a computer, and that goes double for the mother of the bride, the one paying the bill.
The problem with HD is that it is not a video standard, rather it is a marketing term that describes a frame size only (i.e Full HD is 1920 x 1080).
The quality varies widely, and cameras run from under $100 to over $100,000 (not a typo). Along with normal camera parts and pieces such as lens quality and light gathering, the quality is also dependent on the data-rate, the LESS time you can record on a given size card or hdd, the better the video.
The final nail in HDs quality coffin is the compression. Only a fraction of the 25 or 30 frames per second are from light processed by the sensor. In some cameras MOST of the frames are mathematically calculated based on frames ahead and behind.
So, before the merits of SD, the limits of HD...
Really cheap cameras will get 6 or under gb of data per hour.
Name brand, cheap cameras typically get 8 gigs/hr
About $350 or so, the consumer twinkie cams get 11 gigs/hr. This does not change even into the top of the line, $2000, consumer twinkie-cams.
DSLRs get 20 gigs and approach very good quality, but they do have a host of other issues that make them ill suited for recording long events like a wedding. All over the web and here on "Answers".
Pro cameras start at $3000 and get 25 gigs/hr HOWEVER the compression has improved to 4:2:2 intraframe compression, no frame depends on its neighbors. Quality and cost go way up from here.
SD, MiniDv based cameras for consumers are few new, Canon stopped their last one in January, the ZR960. But this format is still popular for pros and TV field use. Remember this frame size is 1/6th that of HD, yet it gets 13 gigs/hr of data and is 4:2:2 compression. In other words, very good quality.
Your problem is that your fellow consumers gave up quality for ease of use. Your only options now, unless you can find unsold DV cameras, is to go with a used camera or spend the $800 or more to get a HDV camera. (HD version of MiniDv, 1440 x 1080 typically).
The other issue is that for consumers, DV and HDV is actually MORE data intensive than HD for storage (The tapes are a built in archive, though) and editing. You will need a firewire port on your computer.
HD from ANY twinkie camera is fine for small screens, computers, phones, youtube. But even on a moderate HDTV it starts to fail in quality. My SD, Canon GL-2's video can be up-converted to HD and is better than native HD the small consumer cameras.
If you can find on, DV will give you better video in more environments. DSLR may be an option, just know their limits. HDV is very good and the best you can get under $1000 new.
Just depends on budget, specific uses and your intended media...
Scott's answer is spot on, but there's still the issue of editing. As Scott said, the HD formats throw away most of the video data - this is fine for the finished product (Blu-ray, DVD) but not good for editing. Most of the frames you want to edit have to be reconstructed on the fly - this needs a lot of computer power. Another problem is that every change you make is likely to degrade the video quality - if your business is providing good quality video, can you afford to do that? Then there's the final render - this will almost certainly be to a lossy format - this has to involve some loss of quality but it's worse if you're starting with a lossy format.
Someone said that cards are easier for editing - the only thing that's easier is the ability to put the card in a reader - it's a very slim advantage!
new is not the same as better. so the real question depends on whether you need "better" because of intended commercial use, or "newer" because its just for home hobby use.
The reason miniDV can be edited by all computer editors, including the freebie ones, is because it is open source code and has not been messed with for over 15 years. yep, a Windows95 could edit miniDV. further, its low compression of 6:1 greatly reduced the computational power demanded of the CPU to keep up in real time. Contrast that with AVCHD which is a proprietary secret invented by Sony and only available to editing programs that are willing to pay exorbitant license fees. That is why it doesn't come as a freebie. And the code is not fixed, AVCHD has undergone significant changes every year since being introduced, moving from a lousy 200:1 compression to a somewhat respectable 40:1 compression in current top level consumer cameras. So if you buy a discounted older model editor, it might not work at all with a new camera. AVCHD was designed by Sony to be strictly amateur grade, Sony designed XDcam for professional use and the differences are not trivial.
IMHO miniDV will continue to be a viable commercial format as long as movie DVDs remain as the primary distribution media. not everybody wants to view videos on a computer, and that goes double for the mother of the bride, the one paying the bill.
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