Low light setup on EX1 Help, please
 

I have read many threads on how the EX1 is excellent in low light situations, but I have not had such luck. I would like to ask any of you how you setup your EX1 to shoot in low light conditions. I am sure I am missing something in the menus. Thanks in advance and I hope you all had a wonderful holiday.

Phil Hanna

Shoot in 720p25, turn the shutter off, bit of black stretch and work out whether you want to use a little gain or pull things up in post.

Thanks, Matt
 

I will give that a try. I have had to do all the gain in post and it comes out grainy. Also, I can't get much of a picture to begin with when shooting, everything strobes!

Phil

Hi,

I would really like to know why you stated it's better to be in 720p than 1080p for lowlight... Using the full resolution of the sensor (1080p) should give better results...

I would just recommend to change the gamma setting (maybe to cine2 or 4, but you better try by yourself) and maybe change the black gamma setting...

You really need to practice depending on what you are shooting and in which situation. This is a big question and can't be answered in few words.

The movie Prune’s Blog Blog Archive Notre Dame de Paris Long version (after the start which is outdoor) was shot inside Notre dame de Paris, France, few days after getting the EX1, without experience or a special profile other than a Gamma change. You really can get good results with basic settings.

It's an extra stop.

I have found that if you shoot interlaced (1080i60) you get better low light performance.

Turn your shutter off as well. You can get away with about +9db and still be pretty clean.

I did a test and rated the ISO/ASA of the camera around 800. Not bad at all.

Daniel Weber

Matt is correct shooting 720P will give you an extra stop.

What's the difference between 720p without gain and 1080p with 6db gain?
The difference is the blurriness.

It's more noise which equates to more stress on the codec which means more artifacts which will degrade multi generation performance. Yes 720P is softer than 1080 but I would take a clean 720P picture over a noisy 1080 one any day. Picture noise in the form of film grain is why channels like Discovery and Nat Geo don't like film. Super 16 is not permitted by most HD channels.

The noise-difference is only caused by the blur caused by the downscaling-component. It won't be clean 720p, if the 1080p-source was noisy, just a bit cleaner. The mpeg2-encoder of the ex1 works well enough, so I could apply that blur/downscaling in post with almost the same result, if I would want to. I don't care about multigen-performance, I like to see a lot of details in the picture and I generally prefer unprocessed footage.
So I clearly prefer 1080p.

No, 720p is not cleaner but it is nearly one stop brighter than 1080p and you don't have to deal with interlace artifacts! ;)

Dennis

I second this statement.

I compared 1080p with 6db (not 0db) to 720p with 0db, but anyway...

720p with x db gain compared to 1080p with x db gain is one stop brighter.
720p with x db gain compared to 1080p with x+6 db gain has (about) one stop less noise.
Why? Because 720p with x db is 1080p with x+6 db low-pass-filtered (=blurred).
From this it follows that if you blur 1080p with x db accordingly, you'll get 720p with x-6 db.
If x<6, then it's not possibly to get that 720p-result in the camera, but only in post with 1080p-footage.

One conclusion is:
If there's enough light to film with 1080p with <6db gain and you want the lowest noise possible (and you don't need a framerate higher than 30fps), use 1080p instead of 720p.
That's also true for 1080i, because it's also derived from 1080p with 6db extra-gain.

Not sure I understand this. Are you saying that EX1 derives 720p from 1080p by applying 6dB gain, then sizing down and blurring the image?

I made a picture profile just for low light. Set to STD4, and push gamma way high, pushed black gamma as far as I thought I could.

Set to 720x30p and 9db gain the camera will see about the same as we do in low light, but it will be grainy. 1080p it see's slightly less than we do, but the picture is much cleaner.

this was 1080p 9db gain with the gamma's pushed.

Trick or Treat 2008 on Vimeo

Exactly. The blurring must be done before downscaling to avoid aliasing (Nyquist–Shannon sampling theorem). So the high-frequency components of the (I guess white) noise are eliminated and so the noise-power gets lower. The sony-engineers decided to use that noise-drop to upgrade the light sensitivity by appling gain. So the ex1 has the same noise at all resolutions but different sensitivities.

This actually reflects my first tests with the Ex3. I compared all the different recording formats in the same light and using all the different gains. After it was all said and done, the winner in my eyes was always 1080p. Some of the others were brighter but you don't want a bright image, what you really want is to see details in low light. I could see more in the available light at 1080p than I could with noisey 720p or 1080i for that matter.

My point exactly. The camera is more sensitive for the same amount of noise by using 720P.

Yes, but you're sacrificing resolution. I wouldn't recommend that.

Another example:
Imagine you have a noisy photo, and you want to print it. Would you really blur it before printing to reduce noise? Well, I wouldn't.

Depends on what you are doing. Excessive noise is a good way to get your programme to fail an HD broadcasters QA checks. Noise is the enemy of modern low bandwidth broadcasts.

Erik I loved the video
 

I really enjoyed the Halloween video. Would you be so kind as to share the settings with me for that light? I will enter them into my EX1 profiles.

Phil

Oh it was very simple. picture profile STD4, I pushed the gamma all the way to +99, black is +1, and black gamma was +5. Plus I always use 1080p and try to keep the gain no higher than +9 for night shots because it keeps the noise in check. If I need more than +9 gain I like to use the 2 frame slow shutter instead. Although you really have to pan and tilt slowly for that..

I am still playing with the black gamma, and black level but you can see in the video they don't look too bad.

Also have some night video in this with the same settings.

Dumont Dunes Halloween on Vimeo

I'm going to try and push black gamma even higher next time I go out, and then return it to +5 to do a side by side, see which one I like best.

You forgot to mention your knee-settings.

I am still learning all this stuff, I haven't touched that yet. :) I guess I will go play with it.

just to put a finer point on it.. let's see one of the other cameras do this. :)

The Orion nebula. 16 frame slo shutter. A little post gain and offset adjustment. I'd love to try this with a lens that can do 50X or something. (open the photo and zoom in to see the nebula. Very hard to capture on video)