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-   -   Owners Thread (https://www.dvinfo.net/forum/jvc-gr-hd1u-jy-hd10u/11517-owners-thread.html)

Steve Mullen July 1st, 2003 08:55 PM

Owners Thread
 
This thread will be for posting information by owners of either the HD10 or HD1.

All may read.

On-topic questions are welcome.

Posts with comments from non-owners will be moved to the most appropriate thread.

Paul Mogg July 1st, 2003 11:21 PM

From Ken Freed at JVC re:shutter etc.
 
Ken Freed of JVC just posted the following reply to me.

The S/A sets auto exposure priority. If you set a shutter value the camera will auto exposure using the iris.

If you set iris the camera alters shutter.

The manual control you desire is not on this unit.

The AGC is the automatic use of the camera's whopping 6dB of gain to keep the image brighter. It does show grain in the image.

Ken Freed JVC
1700 Valley Road
Wayne, NJ 07470
(800) 526-5308 x5419
kfreed@jvc.com

I think I may have had the AGC set to ON while filming some of my clips that I posted, if not ALL of them. So I look forward to trying again with it off. Perhaps that may explain some of the color noise?

Steve Mullen July 1st, 2003 11:44 PM

Re: From Ken Freed at JVC re:shutter etc.
 
<<<-- Originally posted by Paul Mogg : I think I may have had the AGC set to ON while filming some of my clips that I posted, if not ALL of them. So I look forward to trying again with it off. Perhaps that may explain some of the color noise? -->>>

If the term AGC is being used correctly, gain will only be applied IF needed. So you likely didn't add noise.

Steve Mullen July 2nd, 2003 08:37 PM

Finally got my HD10. Two notes:

1. You can "check" the current AUTO set shutter-speed and current AUTO set aperature. That means you can learn where you are -- which is what I hoped.

Now, in AUTO, the EC dial "should" alter just the iris. Since you know where it was before the bias -- you know where it is.



2. According to JVC, the default shutter-speed is 1/30th S. They say it's equal to a zero degree shutter -- not the 180 degree used by the DVX100 or film. The advantage is a stop better sensitivity and more blur to cover the strobbing.

In my house the shutter was usually 1/30th. But, I'll bet it will be 1/60th outside.

So I'm not sure yet which is the REAL default. Maybe there is none. :)

It's possible the AE system keeps the shutter-speed and iris in balance. This could be a problem since speed is so critical to strobing.

Will be testing all weekend.

Joe Russ July 3rd, 2003 01:46 PM

i got mine last week. the closest ive been able to come to controlling it 'manually' is to set the camera to sports mode (1/250 shutter) and then lock the exposure. though the shutter speed is much higher than most people will want im happy with it as long as i can get proper lighting (indoors is a little difficult), thats what post is for.

Steve Mullen July 3rd, 2003 02:23 PM

ASSUMING that my trick reveals the curent speed and iris:

Today with an 8ND filter I found:

The AE system is always in a "programmed" mode. No matter the light, speed never goes below 1/30th nor above 1/250th. And f16 and f/22 seems never to get chosen.

Thus its got some smarts -- or rather the engineers built a lookup table that shows some smarts.

BUT, not only does the camers feel free to chose speeds from 1/30th to 1/250th -- it seems to prefer to change speed rather than f stop! Now that's dumb.

Moreover, I think it may hunt. Under a sudden change to bright light it first goes to 1/250. Then over time it drops back to 1/125. 1/100, amd 1/60th. Each time, altering the F stop appropriatly.

But, the engineers may have had a reason. It looks like the F-stops are discreet. Whereas speed is continueous. Thus, it makes sense to quickly alter speed to keep perfect exposure.

While that logically is OK -- it's a real problem when the frame rate is only 25fps. The widely varying speed is not good for strobe artifacts.

In short, what is OK for a consumer DV camcorder does not fly at 30p.

It also suggests that there is no default speed.

So it looks like one must lock shutter-speed to whatever you want. Which means, you will now be at the mercy of the AE system.

Joe Russ July 3rd, 2003 02:57 PM

or do what i said, which locks the exposure and the shutter speed (just means you'll be at 250, means you need a lot more lighting in doors, and bright stuff outdoors)...if only you could set the default, in sd mode the default is 1/60, i just need 1/60 in hd mode. and then id be happy

Heath McKnight July 3rd, 2003 04:01 PM

I'm wondering if I shouldn't have bought this camera. The auto iris and "searching for an f-stop" thing is really annoying. Esp. since I'm using this mostly for filmmaking.

Nuts...

What about the exposure wheel near the lens? What's that for, the photo mode?

heath

Steve Mullen July 3rd, 2003 04:50 PM

<-- What about the exposure wheel near the lens? What's that for, the photo mode? -->

That's how you bias the AE for exposure control. And how you lock it.

The manual isn't clear, but you need to read this section. ;)

Frankly, I find the AE spot on -- so I'm inclined to simply lock shutter at 1/60th and shoot. (Using 8X ND.) It looks great on an 8 foot screen and JVC HD 19" monitor.

Do not use Auto Focus at 1/30th S!

More tests are needed. I'm off to DC with the camera. No posts. Have a great 4th!

Heath McKnight July 3rd, 2003 05:09 PM

You, too, Steve. Tell me if I wasted $3200!

heath

Joe Russ July 3rd, 2003 07:40 PM

i personally cant deal with AE. if you light a scene, its meant to have a balance between light and dark, and ae will try to optimize whatevers in the frame at that time. that compromises the whole point of setting the lighting in the first place. it would be fine if i was doing a home movie for fun or something, but thats not what i bought the camera for. so i need to lock the AE, ive done sufficient testing for motion artifacts and i can successfully convert the 30p to 24p without stuttering and keep the exposure and frame rate locked....the iris may be wandering, but it doesnt seem to affect the picture...

also, i just bought a tiffen low contrast 2 filter today to compliment the ND filters and my wide angle adapter. Ill see if it improves the low range lattitude...cos the chroma noise in the shadow areas on this camera hurts.....even without gain.

so, i should have some good tests (from a short im making for a video/film class) to show my video post soon.

Heath McKnight July 3rd, 2003 08:00 PM

Okay, how do I lock the AE without the filters and stuff?

I was in Best Buy, hooking it up to HDTVs (don't ask), and aiming the camera all around showed how bad the stupid auto iris is. I need to get rid of that, or I'm screwed with this camera. ARGH!

heath

Heath McKnight July 4th, 2003 12:04 PM

Auto iris nightmare
 
I posted elsewhere that my buddy heard JVC stopped shipping HD10s to re-do the controls. I am now fed up, myself, and being a non-techie, I can't figure out how in the heck to get around the auto iris.

Paul, Joe, Steve, any ideas? If I can't figure it out by Monday, I call JVC and get some answeres. If all else fails, the camera goes back and I buy either an alleged "fixed" HD10 or a DVX100 and wait a while for a new mini-HD.

heath

Joe Russ July 4th, 2003 12:28 PM

i wonder if thats true, if so ill be returning mine for a 'fixed' one when they re-release.....but im guessing that its not true, just cos it sounds too good to be true.

Heath McKnight July 4th, 2003 12:35 PM

<<<-- Originally posted by Joe Russ : i wonder if thats true, if so ill be returning mine for a 'fixed' one when they re-release.....but im guessing that its not true, just cos it sounds too good to be true. -->>>

Chris made a great point: rumor for now. First thing Monday, I call Ken Freed and ask for some help and clarification.

I felt pretty desperate earlier with the auto iris thing. Joe, you gave me a solution. But, what happens when I am shooting a movie, and someone walks in front of the camera? Will your technique stop the iris from adjusting automatically?

heath


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