DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Canon EOS Full Frame for HD (https://www.dvinfo.net/forum/canon-eos-full-frame-hd/)
-   -   Picture Settings (https://www.dvinfo.net/forum/canon-eos-full-frame-hd/472038-picture-settings.html)

Daniel Browning February 4th, 2010 01:05 AM

Quote:

Originally Posted by Bill Binder (Post 1481291)
What's interesting here, the more I think about it, is that although you pick something up by doing a curve on the highlights in 14-bit, you also are giving up a full stop of true dynamic range.

I see it differently. To me, it's trading 1 stop of noise for 1 stop of highlights, leaving the total dynamic range the same in the end. And in some cases, such as high ISO (over 1600), the total dynamic range actually goes up, because there is no increase in noise.

Quote:

Originally Posted by Bill Binder (Post 1481291)
This MUST be the case given the purposeful under exposure by one stop, that's a stop of range I will never get back no matter what kind of futzing it does after-the-fact.

Here is an example of how I see it (assuming the same exposure duration, scene luminance).

At ISO 100 f/2.8, my 5D2 raw file has good usable dynamic range of around 9 stops. The variable pattern noise (temporal FPN) in the shadows limits any more than that (depending on the color balance of the light). A typical raw conversion will put white at 0.3 stops below clipping, middle gray at 3 stops below clipping, and black at 7 stops below clipping. So 6.6 out of 9 stops of dynamic range are used.

At ISO 200+HTP f/4, the raw file, the dynamic range is shifted. The scene luminance that was 0.3 stops below clipping in now 1.3 stops below clipping, and one whole stop of clipped information is no longer clipped. Similarly, scene tones that were 9 stops below clipping before are now 10, and are lost to the pattern noise of the 5D2. Furthermore, all the rest of the tones have increased noise compared to the above. But the total dynamic range is still the same: 9 stops. If the HTP instructions are followed, then instead of using 6.5 out of 9 stops, it will use 7.5: white at 0.3 below clipping, gray at 4 stops below clipping (instead of 3), and black at 8 stops below clipping.

I hope that helps clarify how I look at it.

Scott Aubuchon February 4th, 2010 08:27 AM

wow... head=spinning :P

Great info, so if I'm understanding this right... the only time I should use HTP (talking video) is when I'm in a higher ISO range 800+?

David Chilson February 4th, 2010 09:10 AM

Scott,

I was writing the same question but you beat me to it, I was all for leaving it off. Reading the last couple of posts cleared up nil for me and if I had to know all that to choose settings I would have to take up knitting. I didn't know raw setting could be used for video. On color space I thought everything had a range of reproducible colors, monitors, cameras, printers etc. Then again a letter and card arrived yesterday from AARP, so I'm now officially old.

Manish,

I think that getting a list of different presets would be great, maybe even making a sticky on them. Right now Upstate NY is all white and brown snow and did I mention cold? Numerous bold colors sounds so appealing.

Dave

Daniel Browning February 4th, 2010 10:36 AM

Quote:

Originally Posted by Scott Aubuchon (Post 1481509)
Great info, so if I'm understanding this right... the only time I should use HTP (talking video) is when I'm in a higher ISO range 800+?

Personally, I use it most of the time, at every ISO. I'm willing to pay the price of increased noise at low ISO. But the higher the ISO, the lower the price. Above 1600, the benefits of HTP are "free" -- there is no increase in noise.

Mike Hannon February 4th, 2010 03:41 PM

I also use HTP regularly enough, even though I always feel a bit weird about using it!

One way in which it's easy to see what you get is by installing Magic Lantern and turning on Zebras. Find a high dynamic range scene and observe what's clipping from the zebras on the LCD. Now enable HTP and see how the clipping is reduced.

Then for the scary bit: zoom into the shadows using 10x magnification in live view and turn HTP on and off.

I've noticed that HTP also increases banding noise. If you're delivering in 720p or smaller, much of this will disappear, especially if you add a nice grain effect (if you're into that I am!). But clipped highlights will always scream "VIDEO!" at any size.

Bill Binder February 4th, 2010 04:59 PM

Quote:

Originally Posted by Mike Hannon (Post 1481689)
Find a high dynamic range scene and observe what's clipping from the zebras on the LCD. Now enable HTP and see how the clipping is reduced.

Then for the scary bit: zoom into the shadows using 10x magnification in live view and turn HTP on and off.

But the flipside is...

Find a high dynamic range scene and observe what's clipping from the zebras on the LCD. Now reduce your ISO and see how the clipping is reduced.

Of course you then lose some of your shadow detail, but that's the tradeoff right, that plus the better quantization at 14-bit I guess...

Manish Pandit February 5th, 2010 06:34 AM

5d picture settings
 
David,

I will post the settings most likely tomorrow.
Thing is, I experimented in India with these picture settings approx 6 months ago.

Although I don't now have some of the files and some others will be used in my second film, I noticed that if sharpness went up and I did not use a tripod, then aliasing was definitely distracting to the eye. (the slight movement of the camera hand held was ok for everything but the aliasing).
On the other hand if I used a tripod, (I don't pan or tilt much anyways unless absolutely neccessary), and kept the shot still, even where there was aliasing in buildings, aliasing was still noticeable but acceptable.

Colours wise, I just hate shooting flat video for my documentaries, in India obviously, this matters, colours are superb and very vivid and it is a pain correcting every shot to make it look ..... just the same as with the picture settings. The only difference is with the sky color, where using FCS Colour, I just apply vignettes with variable soft settings to the sky and try and change that hue.
Makes colour correction so much more fun and less tedious in my opinion.


This is one reason where in my current film,now in post, I went back to India and shot everything on a MKii, because the colours are just outstanding out of the box. I had previously shot a lot of stuff with an Ex3, which although satisfactory, the image quality was just not cinematic enough, not to mention the wider angles option with a 14 or 24 mm lens and ability to shoot at night using f1.8.
Of course, this is documentary work only at present, but I can't see myself changing that much when I shoot my medium budget narrative feature next year.

Saraswati Films | News and Events
Films that make a difference


All times are GMT -6. The time now is 07:03 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2025 The Digital Video Information Network