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March 12th, 2005, 04:48 PM | #46 |
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Ken, I haven't tried it, but yes, in a situation where it's simply not feasible to find a suitable camera angle for the camera to use for it's "average" exposure setting (say a spotlit singer on a stage?) then I think the 2-polarizer variable-ND trick might provide a neat way to get to the correct exposure after locking the camera settings.
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March 12th, 2005, 06:29 PM | #47 |
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<<<-- Originally posted by Graham Hickling : >>I would set the shutter to 1/60 and then adjust my angle/position so that brightly-lit parts of the scene filled most of the viewfinder (at which point the camera will set itself to f16 or thereabouts). Then I lock the exposure using Gabriele's method. Then I compose the actual shot I'm after.
-->>> It's still daylight out here in Denver. I did it *exactly* that way 5 mins ago. It doesn't work. Here's what happened: I set the shutter to 1/60, composed the scene as you described, at which point the camera set itself to f11. I turned on Exposure Lock, "L" showing. I toggled the S/A button, it confirmed 1/60th - f11. But the LCD viewfinder immediately began growing darker, and stopped getting darker about 20 seconds later. I toggled the S/A button once more, the shutter had changed to 1/250 and the aperture remained at f11. Exposure was still locked, "L" showing. I released Exposure Lock, and the viewfinder went back to the normal brightness. I toggled the S/A button, 1/250th - f 5.6. The *ONLY* way you can lock 1/60 is to point the camera to a scene of average brightness (if you can find one), and lock the exposure then. You *CANNOT* do it by scrolling the shutter speeds with the menu dial to the one you want, and then choosing exposure lock. It will not stick! |
March 12th, 2005, 06:43 PM | #48 |
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<<<-- Originally posted by Ken Hodson : Could we not lock the shutter/exposure by aiming at the darker scene then aim at the brighter scene and use ND's or a variable ND to bring the exposure down? -->>>
You could also just aim at the brighter scene and then add ND until the exposure came down, and then lock it. Then you could confirm what you're getting by toggling the S/A. To me despite the good intentions, the most important discovery of this whole thread was the recent observation that you can toggle the S/A button to confirm exposure settings while the exposure is locked. |
March 12th, 2005, 07:41 PM | #49 |
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"To me despite the good intentions, the most important discovery of this whole thread was the recent observation that you can toggle the S/A button to confirm exposure settings while the exposure is locked."
True. It is very important find. "You could also just aim at the brighter scene and then add ND until the exposure came down, and then lock it. Then you could confirm what you're getting by toggling the S/A." Tried that (was a beautiful day here on the Sunshine Coast(lower B.C coast) I would cycle through thew S/A to confirm my increased ND has me where I want. 1/60th F5.6 or so. I would verify this a few times by cycling through. As soon as I lock my exposure"L" I cycle through S/A again and I am at 1/30th! There seems to be a conflict. Natural exposure won't let you get down to 1/60 if it is too bright. If you ND it down to 1/60 then set exposure, exposure then seems to read too low and reset to 1/30th because it is too dark. I thought I had sucess with this technique the other day. I was shooting in much lower light levels and my settings always seemed to stick. Indoor and outdoor. Today in the bright sun I had no luck with these techniques at all. We need to beg. plead, force JVC to give us a firmwear that alows 1/60 lock. They should (owe us!) some respect for being the pioneers here. I am thinking about using this cam only in studio type situations, only.
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March 12th, 2005, 08:17 PM | #50 |
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>>>I set the shutter to 1/60, composed the scene as you described, at which point the camera set itself to f11. I turned on Exposure Lock, "L" showing. I toggled the S/A button, it confirmed 1/60th - f11. But the LCD viewfinder immediately began growing darker, and stopped getting darker about 20 seconds later. I toggled the S/A button once more, the shutter had changed to 1/250 and the aperture remained at f11.
..... it's really starting to seem that our two cameras are behaving differently. Once I have the "L" showing, neither shutter nor aperture ever vary from that point on - regardless of whether I'm pointing it at bright sun or deep shadow - and I can cycle (quickly)through S and A whenever I need to confirm that they are both still where I want them to be. Perhaps your camera reacts a bit faster than mine, so that the 0.5sec or so that it spends on the S and A setting is enough time for yours to start resetting itself, whereas mine stays put where it is??? Weird! |
March 12th, 2005, 08:20 PM | #51 |
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>>>We need to beg. plead, force JVC to give us a firmwear that allows 1/60 lock.
YES!!! How frickin' hard could that be... |
March 12th, 2005, 09:31 PM | #52 |
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<<<-- Originally posted by Graham Hickling : >>>
..... it's really starting to seem that our two cameras are behaving differently. Once I have the "L" showing, neither shutter nor aperture ever vary from that point on - regardless of whether I'm pointing it at bright sun or deep shadow - and I can cycle (quickly)through S and A whenever I need to confirm that they are both still where I want them to be.-->>> Put the camera on a tripod, and point it at a bright scene. Give it a minute to warm up and stabilize. Cycle quickly through S and A. If the scene is bright enough, the default shutter should be around 1/250. Next put it in shutter priority mode, and use the menu wheel to turn the shutter down to 1/60. Now turn on Exposure-Lock, and watch what happens in the viewfinder after about 20 seconds. |
March 12th, 2005, 10:57 PM | #53 |
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I've only tried what you asked a couple of times, but ... to get the camera to set its initial shutter at 1/250 I found the scene had to be bright enough that the corresponding f-stop was around f16. So I couldn't then dial down to 1/60th because there wasn't a small enough f-stop available for the camera.
From an earlier post: >>> Yep, that's an additional complication. When you first lock the shutter, it has to be at a speed where the camera can achieve correct exposure with an available f-stop (i.e. somewhere between f1.8 and f22). In that situation, the method we've been discussing [seems to] work. I'll try some other combinations in the morning (it's 11:57pm..) |
March 12th, 2005, 11:10 PM | #54 |
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By the way, Tom, I can see I've been kinda missing your point for the last few posts. I've been saying how the camera WILL stay put at the shutter speed and aperture it gets locked at (and that we can check both settings by toggling S/A).
Whereas you are saying (I think) that the shutter speed the camera locks at sometimes is not the speed we intended, and indeed not the speed visible in the viewfinder at the point in time when the lock button gets pushed. |
March 13th, 2005, 12:00 AM | #55 |
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<<<-- Originally posted by Graham Hickling : I've only tried what you asked a couple of times, but ... to get the camera to set its initial shutter at 1/250 I found the scene had to be bright enough that the corresponding f-stop was around f16. So I couldn't then dial down to 1/60th because there wasn't a small enough f-stop available for the camera.
-->>> At around 5:30 pm, just before twilight under a partly cloudy sky, the lighting was flat, with non-distinct shadows. When I first turned the camera on and cycled the S/A button, the shutter was 1/60 and the aperture was f11-f16. But after about a minute of warm-up, that changed. I cycled the S/A button again, but now the shutter was 1/250 and the aperture was f5.6. This was with the camera on a tripod, not having moved it. But with the flat averaged light, it really didn't much matter where the camera was aimed. 1/250 at f5.6 was where it wanted to be, whether aimed down at my brown lawn or across the street. I had the requisite exposure latitude for shooting at 1/60 without overexposing. Earlier in the day when it was bright and clear, I used 4x ND. So I acknowledge your point about the camera having to be within the range of exposure latitude for 1/60, i.e. f-stop less than f16-22. |
March 13th, 2005, 12:17 AM | #56 |
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<<<-- Originally posted by Graham Hickling : By the way, Tom, I can see I've been kinda missing your point for the last few posts. I've been saying how the camera WILL stay put at the shutter speed and aperture it gets locked at (and that we can check both settings by toggling S/A). -->>>
And on that we agree, the camera WILL stay put at the shutter speed it gets locked at, if you use that method you described earlier, of aiming the camera at an averaged scene that just happens to give you 1/60 shutter when cycling fast thru the S/A. But what I'm saying, is that if the scene you're composing doesn't just happen to give you 1/60 when cycling fast thru the S/A, then if you attempt to force 1/60th by turning down the "Menu" dial, it WON'T STICK once you go to Exposure Lock. Even weirder, is if you had turned the shutter down to 1/60 and it had been at 1/250 before, by the time you get the exposure lock "L", you cycle fast through the S/A and it reads 1/100, so you think you're locked there at 1/100th, but you're not. It will keep on slowly changing all the way back to the default 1/250 over the course of about 20 seconds, and the viewfinder will gradually go darker at the same time. Once it finishes this slow ramping, the exposure is locked, but not with the correct exposure for the scene and not at the shutter speed you hoped for, 1/60. But truly locked thereafter it will remain, whether you put the lens cap on or point it at the sun. Also, if you just turn the camera on and don't give it a minute or so warm-up, when you cycle fast thru the S/A button, it will likely show you 1/60 shutter. But leave it aimed on that exact same scene for more than a minute and try again. It will likely have changed the shutter speed to something faster, in my case today it was 1/250. |
March 13th, 2005, 12:55 PM | #57 |
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>>>If you just turn the camera on it will likely show you 1/60 shutter. But leave it .. for more than a minute .. it will likely have changed to something faster.
OK, you are indeed correct. I think the above statement explains what has been going on - my camera often ends up powering-down while I'm fiddling around without filming, and consequently a lot of my S/A toggling has been within a few moments of it powering up again, so I usually got it locked onto 1/60th without realizing why that was actually a bit of a "fluke". (One has to wonder what drugs the JVC firmware dudes were on when they were setting up this camera .) |
March 13th, 2005, 07:28 PM | #58 |
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This must be the same thing I am finding with my variable ND trick. As I stated in my last post, I would increase ND levels untill I could get a 1/60 S/A. I would then lock the exposure only to cyclr through and find it at 1/30 soon after. I am going to try to go slower with the variable ND's and see if I can get it to fully settle on 1/60 befor I lock.
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March 15th, 2005, 12:22 AM | #59 |
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Locking the aperture the old fashioned way.
So JVC obviously didn't want this camera to lock exposure.
What if I so a little mod to the lens assembly and *physically* lock the f stop while the camera is set to 1/60 sec. I wonder if the firmware would decide that the camera is defective (and error out ) as it frantically trys to alter the fstop ? I've taken apart cameras before, but it is a risk the first time on a new model. -Les |
March 15th, 2005, 01:58 AM | #60 |
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In a way I can't figure out why JVC hasn't offered a firmware update for this issue. With the HD100 on its way it would be a good PR move to show that they stand behind their products.
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