I'm having a problem Locking the exposure. Whenever I zoom in for my Redrock M2 DOF Adapter, the f goes to 2.8 or whatever. but I thought the f should be locked at 1.8
Is there a way round this?
I'm having a problem Locking the exposure. Whenever I zoom in for my Redrock M2 DOF Adapter, the f goes to 2.8 or whatever. but I thought the f should be locked at 1.8
Is there a way round this?
Lock your exposure while fully wide. Once it's locked you're good. The numbers will change as you zoom in but the exposure will remain the same.
Zoom lenses with as much "reach" as the HV20's 10x which can hold a constant stop throughout that long zoom range tend to be big, heavy and expensive.
i tried this and eventually got it right after maybe an hour of trying , but i dont get the point of this, i had my camera at +11 with a f1.8 aperature but the mildly lit room was way too dark for practical use, i dont get the point? its not grainy but its too dark to see . (i locked at f4.8 like someone suggested)
Im gunna try this again.
People can explain how to do the exposure lock trick and even why you might want to do it. But they can't tell you exactly when you should use it, because they can't know what any one individual is trying to accomplish with their video shoot. In your example, the room is not brightly lit enough to get a decent shot with 0 gain. To fully understand the exposure lock trick, you really need to experiment further. Unfortunately, although the HV20 will display f stop and shutter on its the LCD display, it will not show the gain. However, you can display the gain using the program HDVdataMon, which you can download from HV20.com:
HDVdataMon
This utility will display shutter, aperture and gain from the HV20, although with some NTSC camcorders (like the HV20/30), the program does not display the shutter correctly. Try changing the modes (like "night", "fireworks", "sports", etc.) on the HV20, while it is connected to your computer and HDVdataMon is running. Try the exposure lock trick (including the "double-bumping" trick) and you will see how each mode is programmed. Some modes have no gain. Other modes try for the highest shutter speed possible. Others, like cine mode, try to maintain a specific shutter speed like 1/48, when shooting with the cinema mode 24p (PF24).
If you search this forum and read every thread on the exposure lock trick, you could probably understand when to use it and when it makes no sense to use it. But IMO, if you really want to get a feeling for when to use it, tinker with the HV20 and HDVdataMon. By understanding the interplay between aperture, shutter and gain in the HV20's preprogrammed modes, you can understand how to use the same three variables in manual mode.
The goal you are shooting for is to not have electronic amplification (gain) of the light. Gain causes a grainy, pixelated look in response to an area without enough light.Originally Posted by milespapineau
When you lock the gain off you MUST provide light, and cameras are never as sensative as the human eye. So even if it looks OK to you it may not be lit up enough for the camera.
Add some lighting, lock the exposure, then move the exposure + or - so it looks decent but not over exposed. The 70% zebra is helpful. With even lighting if you have some small areas with 70% zebra stripes you are probably about right.
Duke
"70% zebra stripes you are probably about right"
So what's with 70% zebra stripes? Why the 70 and not 90 or 100? can you better explain how you use the zebra stripes? I have basically been using it at 90 or 100, and cutting back when I see any.
-- Dave
Zebra stripes....
It just depends on how you use them. At 100% if you have zebras showing you've blown out your highlights and can't get them back in post. At 70% zebra stripes you can show little bits here and there, then exceed that a bit and you'd be ok. The idea is to create even lighting if possible.
Best practices would probably be to switch back and forth between 70% and 100% just in case.
I only recall seeing 70% and 100%. I don't recall actually seeing 90% on this camera.
Duke
Slightly off topic but relevent
I cant seem to be able to subscribe to this thread and be notified by email.
Am i missing something please?
thankyou
tutorial section
Well, the subscribe option has appeared. Thank you and I am now subscribed.
Duke, this is tremendously helpful, as it is so elemental to good film and isn't well described in the manual. Thanks for taking the time to explain it crisply. It helped me figure out two features - zebra and white balance setting - and how they impact my work, and tie that to proper exposure.
Looks like a great program. Where did it come from?
Duke
It's from a German site. I think I saw the link in a post somewhere here. Maybe a search would turn it up. IIRC, the program only works for PAL cams.
Good luck.
Dennis
It's from a German site. I think I saw the link in a post somewhere here. Maybe a search would turn it up. IIRC, the program only works for PAL cams.
Good luck.
Dennis
THis has confused me because my understanding is that, once you've reached 1.8, if you push the exposure up any further you are adding gain. If speed and aperture are locked, then as you push up the exposure, it is the addition of gain that makes the image brighter. Is this correct?
I have a difficult time getting the fstop to settle as I move around the light source. It ends up taking me a long while to lock at 4.8.
I'm curious. Does anyone know if this lack of gain control is also an issue on the Sony HDR-HC9 or the Panasonic HDC-SD9?
This statement is not accurate. Even with "locked" exposure, it is possible to engage the electronic gain. You have to watch your f-stops. If they stop moving, yet your image is getting brighter, you've moved into electronic gain.If you've locked the exposure, gain (electronic signal amplification causing degradation) doesn't kick in. Ever. That's the point of all this.
The goal is to lock the exposure at a 0 at an f-stop of 4.8, which gives you pretty much the whole +/- range without gain.
Hey, Duke,
Does this trick work with the HV30 as well?
I've been trying, but I'm having a hard time getting control of my aperture. When I adjust my exposure, the aperture reading stays the same.
Also, my main concern is gain. So, how do I know how much db's of gain I'm at in correlation to my aperture and or shutter speed?
Thanks,
Trey
> I've been trying, but I'm having a hard time getting control of my aperture.
> When I adjust my exposure, the aperture reading stays the same.
Lock shutter speed, then EXP will control aperture/gain. If you see the same aperture in 3.0-1.8 range, this means gain is up. If you see the same aperture at 5.6, this means ND filter is up.
> Also, my main concern is gain. So, how do I know how much db's of gain
> I'm at in correlation to my aperture and or shutter speed?
With locked shutter speed, each EXP step is 1/4 of f-stop or 1.5dB.
I'm pretty sure that I "initialized" my SD card, but not totally sure.
How can I know for sure whether or not the card has been initialized. The camera recognizes the card and gives me my aperture readings when I half push the photo button. Does this mean the card is initialized?
Thanks,
Trey
That only means the card is present, not initialized.
Is there a download option for mac users?
Trey
Sounds interesting, i'm just about to buy a mini sd card, but i suspect your right. As soon as i get a card, i'll give it a try.
Cool... i only did the last step "SETTING EXPOSURE WITH A DOF ADAPTOR" and now the HV20 only shows true darks or true lights. I zoomed in to a pitch black section of my room and it didn't try to add gain or anything.
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