"amer" <seymoria@yahoo.com> wrote in message news:7d1e8174.0307121701.1850ba82@posting.google.com...

> I am looking to buy a camcorder but cannot understand most of the

> technical jargon in the specifications. Can you please help me

> understand some key aspects of camcorders as follows? Thanks a lot for

> your time and advice.

Most of the specs tell you little about how good the picture is

(see: www.David-Ruether-Photography.com/vid_pict_characts.htm), how

good the sound is, or how good the controls are - and these

are what is important... (besides price, size, or whatever...;-).

> ===============================================

> LINES OF RESOLUTION

> ===============================================

>

> First, how important is resolution ? Lines of Resolution are

> different in the models, e.g. 500 vs. 530. (for Sony TRV-19 & TRV 70).

> How much high should I go?

This spec tells you (at best!) the absolute maximum under ideal conditions

of lighting, aperture, and distance what the camera *may* achieve, but

in practice, it will likely be less. Higher resolution is generally better, but

under some circumstances, it can degrade the image (depends on the

camera...).

> I have also read that resolution doesn't make any noticeable

> difference during playback on a plain TV. Is that correct?

No. On a good TV, you will easily spot the TRV19 vs. the

TRV70 - though not necessarily in all good ways for the sharper...

>Do they

> actually matter during playback and video stills? Or do I need to have

> a High definition TV to actually notice the difference?

No. I can easily see the differences on my 12 year old Panasonic 27" - but

it was one of the higher-resolution models of the time... The stills will be

MUCH better from the higher-res camera - but this does not mean they

will make good prints...

> ====================================================

> CCD SIZE / NO. OF PIXELS

> =====================================================

>

> Example Comparison paragraph b/w Sony TRV-19 & TRV-70 :

>

> "The TRV19 uses a 1/4" CCD, with a modest 680,000 pixels. Of that,

> 340,000 are actually used for video. The TRV-70, uses a 1/3.6" CCD,

> with 2.11 million pixels. Of those, the TRV70 uses 1.92 million for

> stills, and 1.08 million for video. The jury is still out on whether

> or not those extra pixels really help with video quality. "

As I said, the image will be sharper (and have better color), but

some high-res 1-CCD cameras also have annoying levels of

motion-artifacting with high-contrast edges - so it may be a toss-up

for preference, but the pictures are clearly different...

> Firstly, I cant understand that CCD size is almost the same in both

> models , but the no. of pixels have increased? Why?

For better resolution and color... There is more info to interpolate

from for forming the final image.

> 2ndly, why is the number of pixels used for video less than that for

> the stills?

Some are used in "overhead", quite a few for the stabilizer...

> 3rdly, many models boast a 'Megapixel CCD'? Does that make higher

> resolution video? Or is this feature only used in still photos?

See above - and there are many megapixel+ CCD camcorder models...

> Finally, is CCD size related to resolution? A common CCD size is 1/4".

> Should I go higher than that for better resolution?

CCD size affects sensitivity and tonality, not resolution...

> ==================================================

> LENS

> ==================================================

>

> Example Comparison paragraph b/w 2 models :

>

> "The TRV19 has a 10X "Carl Zeiss Vario-Sonnar" lens. This lens has a

> focal range of 3.3 - 33 mm, which is equivalent to 42 - 420 mm.

> The TRV70 has a very nice 10X Carl Zeiss Vario-Sonnar T* lens --

> Sony's "premium" camcorder lens. This lens has a focal range of 4.5 -

> 45 mm, which is equivalent to 52 - 520 mm for videos, and 39 - 390 mm

> for memory card shooting."

>

> My question is : How does focal length of the lens affect the video?

Only in angles of view...

> Moreover, why is the focal length different for digital cassette video

> and for memory card shooting?

Different areas of the CCD are used, affecting the resultant angles

of view (put a 100mm lens on 4x5 film and it is a wide angle;

put the same lens on 35mm film and it is a tele...).

> ======================================================

> LUX / ILLUMINATION RATING

> ======================================================

>

> The 2 above Sony models have 5 lux and 7 lux illumination ratings

> respectively, but both have the Nightshot feature and can perform

> night time video in infrared. So, whats the benefit of 7 over 5 lux?

None. The lower number indicates that the camera will shoot successfully

in lower light levels...

(See: www.David-Ruether-Photography.com/camcorder--comparison.htm for a comparison

in various light levels of 5 different Sony CCDs...)

> =====================================================

> INPUT / OUTPUT

> ======================================================

>

> Both models support USB/S-video/A-V connectors. But one model has

> only outputs for these while the other has both input & output for

> them. Is the benefit only that I can dub my old VHS tapes into digital

> format with the 2nd model?

Yes. But use only the FireWire connection for high-quality in/out

of the digital signal, with the analogue connections used when converting

to/from digital - use the USB for stills and low-quality video...

> ==============================================

> RECORDING MEDIA

> ==============================================

>

> Which format has the best resolution, Di8, Mini-DV, or Micro-MV? And

> what about Hi8?

D8 and Mini-DV (and essentially DVCam) are all the same format

in terms of signal - but D8 models tend to have "lower-end" feature-sets.

Hi-8 was a good analogue format, but digital is generally preferable...

> I understand that digital camcorders also use cassette tapes like the

> old Hi8 and VHS. Does this deteriorate video quality after prolonged

> use such as happened in the old analog cassettes, where picture was

> often soiled and snowy when it the tape got old or worn out?

Digital info can degrade considerably before it is unreadable - it's

somewhat like plastic cars: they don't dent easily, but hit them just

hard enough, and there is catastrophic failure... DV tapes are

remarkably durable.

> -------------------------------

>

> Finally, I must tell that size is my prime consideration, and the 2nd

> is high resolution.

I would go for high resolutuion, good color quality (a complex issue),

good (normal, not high) contrast and tonality, good sound (a complex

issue), and good control ease of use and capability. This usually means

going to the best 3-CCD units (which are FAR from the smallest).

In tiny cameras, look at the Sony PC101/105 for a good compromise

between performance and size (the contrast is high, the low-light

range is limited, but the image is sharp and the color is good...).

--

David Ruether

d_ruether@hotmail.com

http://www.David-Ruether-Photography.com

Hey, take a gander at www.visitithaca.com, too...!