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View Full Version : Getting a solid image.



mhill310
12-16-2009, 10:28 AM
I have read the thread about the tricks to getting noiseless video 100 times and maybe my brain doesnt work right or something but I just cant seem to get it to work. Would someone be able to explain to me in a better way how to do that so I can make my camera useable? Because unless I shoot outside or under tons of artificial light there is noise. And sometimes even under alot of artificial light it produces a lousy image. So please explain it to me.

I have a d5000 with a 50mm 1.8 lens.

Jester2138
12-16-2009, 10:54 AM
Well, you will always have noise in low-light situations, it's inevitable. The trick is getting as little noise as possible. Since the D90 does not have manual controls, the only thing you can do is use manual lenses and the fastest f stop. So, on your 50mm 1.8, use f/1.8. However, if there is no aperture ring, you will either have to "hack" the lens to force it's aperture fully open while it's on the camera or just live with the camera controlling it.

mhill310
12-16-2009, 01:31 PM
But what's the deal with like tricking the camera to think it's on 5.6 then opening the aperture wider. How does that work.

Ruzo
12-17-2009, 12:25 AM
I think that the trick is to lock AE before switching to liveview.

damonb
12-17-2009, 05:43 AM
This all depends on what you are shooting. Live events? Music clips? Shot films? etc.

You can lock after live view, which is what you would do when metering with a grey card. If you are experimenting with no card or light support, switch to LV and wave the camera around, finding the exposure that pleases you, then lock. If you use a card, make sure it is reflecting your main light source. All of your camera settings matter prior to going in to LV and locking exposure, and despite what some say, so too does exposure compensation - go into LV adjust EC, video, and adjust EC again, and see for yourself. Take a still first and review your histogram and reported settings, etc. This gives your subsequent settings for video a good start. You need to play around in all lighting conditions and get comfortable with the way the camera works.

What you cannot do is manually set the camera for video, but if you get to know the working of the D90 as a video AND STILL camera device, you can effectively use it as a manual video device.

The 'trick' spoken about is to lock exposure in LV and then turn the manual aperture ring on the lense, therefore letting in more light than the auto video camera settings (that you cannot change) were set for. That is why people advise getting older manual (but still AI) lenses, or even early or expensive AF lenses that have the manual aperture ring. I have found that this very rarely produces good results. Others many differ on this assessment.

Remember the dictum that if the light is too low, the professional adds light. For a convincing image, reducing light in post is easier than adding it. While it's a different process, that's why film makers on the cheap used to shoot day for night.

And don't be fooled by the other dslr video cameras - all of them produce noise in low light. The revelation here is that on so many camcorders of the past, low light meant no image at all!

mhill310
12-17-2009, 08:45 AM
Thanks so much, that was so helpful. I guess it means really that I have to add all the light I need. Other issues I have are like pixely blocks in the video. Any idea what causes that?

Ruzo
12-17-2009, 11:31 PM
These were the first steps to achieve low noise described by Kholi:

....1. Without engaging LV mode, set the camera in Manual Mode. If you're already in
....... Live View, exit.
....2. Turn on AE-L (hold), you can check to see if it's active by peerin' into the viewfinder for the AE-L icon.
....3. Close your Iris down to an f5.6 ~ 8
....4. Aim the camera at a wall or surface that's brightly lit. It should not be blown out, but bright. ....I would say just about sixty-percent (60%) Exposed or a little more.
....5. Activate LV mode.
....6. Open the Iris to a 2.8 or 1.4 and check the cleanliness. Not to mention the 1/30 ~ 1/60th shutter. Mmmmm. Delightful.

damonb
12-18-2009, 01:02 AM
Yeah, number 4 is critical and for repeatability you should use a grey card reflecting your main light source. In Kholi's thread I think people settled on the idea of a 20% grey card or thereabouts, something you can get from your photographic supplier. Remember that you need a lens with an aperture ring to do this!

Michael Carter
12-18-2009, 11:35 AM
My experience is you need a LOT of light for a really clean look. But... when you start to get some grain, I find it's still a "pretty" image.

I have older manual AI primes, and newer AF primes and zooms, but all of my glass has aperture rings. They're not all crazy expensive - the 18-35 3.5/4.5 can be found for about $350 and makes a good "normal range" zoom for the small sensor (but you don't get the 2.8 aperture with it). There are dozens of 50mm 1.8 Nikkors, Vivitars and Sigmas out there, too. Thing is, I haven't shot much video under F4 unless I want really shallow DOF, but I've shot Nikon forever so I have a good range of glass.

Older manual primes generally have far better damped focus than AF lenses (which I assume are optimized so that focus motors can turn them easily). Look for Nikkor Series E lenses on eBay, older Vivitar primes, etc - with the JPEG video, you don't need a $1000 super-sharp lens. I got a Vivitar 28mm 2.8 for about $50 which is killer with the D90. A nice tight focus ring really helps with manual focusing.

One thing you really have to do is shoot some stuff, drop it into your NLE, and watch it in your editing environment AND watch the clips on the camera LCD- chances are the LCD is a little bright; basically, "calibrate" your LCD brightness by visual comparison. I turned mine down a click or two.

If you're running & gunning, here's some tips that work for me:

Set the camera to Manual; set the image controls you want.

If you're using older manual AI lenses (non-CPU lenses), set at about F4, frame the kind of lighting your scene will have, hit AE lock, and start recording - you'll have a stop or two to open up if needed. (For video I find the camera wants to shoot a little darker than I want, I like to leave a stop to open up - especially since highlights looks pretty nice with the D90). If light is really low, start wide open.

With newer CPU lenses with an aperture ring, go manual as above. UNLOCK the aperture ring, but leave it closed down (usually F22). You can only enter live view with a CPU lens if it's stopped down fully. One in live view, open the lens as above and engage AE lock where you want it.

With a CPU lens as above, every time you stop recording, you have to crank the lens back closed, hit live view, disengage AE lock, open up, check exposure, engage AE lock, etc. It's a few extra steps, and if you're trying to match all your shots, it's going to be tougher.

I just shot a live music event with two stages - one well lit, the other very dark. I had a DVX on a crane, but the coolest shots I got were with the D90 on a fig rig. For the darker stuff, I locked setting at about 5.6 and opened all the way up - they're noisy, but it looks fairly "film like" to me, and I caught some cool, frenetic stuff - my edit is really crazy & energetic and I don't think the average viewer "sees" the grain.

I think for my style of working, I need to get rails & a follow focus, some kind of ghetto steadicam, and either use my 7" LCD or get an HDMI monitor, and use a focus whip. I've found focus to be the hardest thing for handheld with DSLR video.

But until there's an affordable cinema-style video cam with good DOF and highlight rendering (I got scolded for using the word "Sc*rlet" earlier but this summer looks very exciting to me) the D90 does come close to the look I'm after, without a big adapter rig and the associated hassles and quality issues.

And the D90 is one hell of a still camera, the image is a marked improvement over the D80, D200 & D300. And I still make most of my income on the still side, video to me is icing on the cake, even with its flaws.