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-   -   TO: 1-CCD Camcorder Owners (A Question About Shutter Speed) (https://www.dvinfo.net/forum/open-dv-discussion/15692-1-ccd-camcorder-owners-question-about-shutter-speed.html)

Dave Largent October 13th, 2003 04:04 AM

TO: 1-CCD Camcorder Owners (A Question About Shutter Speed)
 
What is the slowest shutter speed the camera can go to in normal, fully automatic mode? For example, if you tried to shoot some video in a very dark room -- without putting the cam into any special AE program mode such as "nightshot" -- the iris would be wide open. What would the shutter speed be? 1/60th?
This info is requested because I'm doing some investigation of low-light camcorder tests where the cams were compared when in their regular full auto mode.
It has been pointed out to me that image stabilization being on or off may affect the minimum shutter speed. I would be interested in the shutter speed with the cam in its default image stabilization setting, which I would think would be "on".
Make/and or model number would be appreciated.
Thanks for any assistance in helping me to help others on this board.

Frank Granovski October 13th, 2003 01:04 PM

Quote:

What is the slowest shutter speed the camera can go to in normal, fully automatic mode?
Most consumer cams will do 1/7.5 of a second, or there abouts. Why do you ask?
Quote:

the iris would be wide open. What would the shutter speed be? 1/60th?
This would depend on how much light there is. Why not use light bulbs or candles for the test?

www.dvfreak.com/lux.htm

Dave Largent October 13th, 2003 06:28 PM

Hi Frank,
The reason I've asked these questions is the Low Light
Shoot Out test charts have already been published as an aide in helping someone to choose a camera. The tests were conducted in very low light -- much less than normal home interior light. The cameras were set on a tripod and put into fully auto exposure mode. Now, most of these cams have around the same maximum lens aperature of f/1.7 or thereabouts; due to the low level of light I know they're all going to be wide open so they're all even in this regard.
I'm currently in the market for a cam to do some low-light handheld work. Say I look at the comparison results and see that Camera A has much more low light reach than Camera B, so I go buy Camera A. But once I've purchased it, what if I'm disappointed in the low-light reach based upon what I had expected -- after having seen that Cam A's picture of the test chart was much brighter than the the rest. And what if I come to find out that Cam A was tested at 1/4th of a second and Cam B was tested at 1/100th of a second. Perhaps at the handheld shutter speeds that most people would be using, Cam A (tested at 1/100th) really would give a better low-light picture -- or perhaps it wouldn't. Unfortunately for me, the shutter speeds that the cams in the comparison were at when tested were not listed. Also, unfortunatly, I haven't been able to get this slow shutter info from the manufacturers, either. So I turned to y'all here to see what more I could find out from persons who may have cams the same (or similar) to the ones I'm considering purchasing.

Frank Granovski October 13th, 2003 06:58 PM

I get it. You're trying to figure out which cam shoots best in almost no light. Here are some good ones:

GR-DVL9500U
Optura PI
PV-DV852
PV-DV601
TRV11
TRV17
Elura (the original)
Optura (the original)
GR-DVL9000

But for best results, turn DIS off (if the cam has this), and use the manual settings.

I also found the TRV30 not that bad in lower light when I played with it in auto mode, but not as good as say an Optura PI.

For a good inexpensive 3 chip cam, the GS100 is not bad with lower light. But cams with bigger CCDs and less pixels are usually better (with lower light).

Keep in mind that with many of today's cams with a high video effective pixel count, captures at higher resolution. The trade off is usually "low light."

Brian De Leenheer October 14th, 2003 05:03 PM

To add to Frank's post, I have tested a Canon Optura Xi, Sony TRV 38, TRV 39, TRV70, Panasonic PV-DV953 and GS70 and my trusty Sony TRV11 is far superior to all of them in low light. In bright light, the newer cameras give better video quality and colour, however. I wonder if the move to higher pixel-count CCD's for still images is hurting video performance in low light.

Brian

Frank Granovski October 14th, 2003 05:49 PM

Yes, the TRV11 is good in lower light also. Probably because its 1/4" CCD has a low pixel count in which 340K is video effective (from what I recall). I wonder if lower pixel counts = larger pixel sizes; and the larger pixels pick up more light?

Josh King October 16th, 2003 01:04 AM

Yeah, it's true. The larger the image sensor pixel, the less light is needed for it to "pick" the image up.

Here's a brief description on how image sensors work. It's for Digital Cameras, but most of it applies to Video Cameras as well. http://www.dpreview.com/learn/Glossa.../Sensor_01.htm

Generally, the larger the image sensor pixel, the better low light preformance. The size of the CCD can also contribute to the amount of noise.

In some of the Digital Cameras (not sure about video cameras), they actually put small lenses (microlenses) over each pixel to gather more light. This has its tradeoffs, but generally results in better low-light preformance.

My Sony DCR-PC110 (consumer) camera has a *feature* ithat allowed you to let the camera slow down the shutter, based on the amount of light. It was called Sony SuperNightShot, and it basically slowed the shutter down until it could get a passable image on the screen.

The good part was it always got an image, even in starlight. The bad part was that the shutter was extremely slow, therefore you had to have the camera on a rock-steady surface or the image blurred beyond recognition.

Norm Couture October 16th, 2003 07:12 AM

SuperNightShot is an evolution of the Sony NightShot feature which is infra-red sensible, but with a 1/4 sec. shutter speed. In video, it'll give you 4 series of about 7 identical frames per second, making it a very choppy movement of very blurry frames. It's virtually useless, unless you want to know what kind of kritter tears your garbage bags apart at 2AM in complete darkness...

To answer Dave's question, in full Auto mode, NTSC camcorders should "idle" at 1/60, while PAL do it at 1/50 sec. This basic setting changes when you select a specific AE program such as "Sports" (1/1000), "Portrait" (variable), "Candlelight" (1/4), or when you switch the Electronic Image Stabilizer On.

There is also another menu to select between 3 or 4 SlowShutter speeds (1/30 to 1/4), which will maintain the exposure of only one field during the specified time in a buffer memory while discarding the other field completely: loss of vertical resolution.

Paul Tauger October 16th, 2003 10:37 AM

My old TRV-20 did okay in low light if I turned off the EIS, put it in manual exposure mode and set the shutter speed to 1/30th of a second. Of course, it doesn't compare to my VX2000.

Dave Largent October 16th, 2003 11:06 AM

Norm and the rest: In case you missed it, Robin's $400 evaluations are out. Already "evaluated" them to the degree my humble self can. Surprised to see the degree consistency of image *by brand*. Need to get to the cam store soon to check
comething out with a hands on.


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