Improving detalization in hacked GF1

[Pipis213]

I agree that the 180 degree shutter rule is important. However, I don't agree that it should always be adhered to. There are many situations where 1/60th of a second or greater shutter speed will get you nothing but a back screen. In those cases 1/30th of a second shutter speed can work if you get everything else right.

I agree with you. But also think that 1/180 rule is not about detailing of a scene. It may connected with objects and subjects movements but details - only if a camera shakes because of tremor of hands or if the camera has rolling shutter.

I've reviewed your videos and can't say that they are disgusting, they are pretty instead.

 

[Pipis213]

The Studio test

The Studio test

Hi All!

This is the promised fast hand studio test. The light source was just a pilot light from a photo strobe light stand.

(in full window it is here http://www.youtube.com/watch?v=TbLgwjY7Ggo)
I'm quite satisfied with the details, movements, lighting. Except strange lightness step gradient at the background. It is not so obvious at the still below but much better visible directly in video:


Why it happened? What may cause that? I shot in AVCHD Lite.

BTW I also shot the same scene using Canon MarkII (MJPeg, 1080):

I liked GF1 output much more, the only thing which I'd like to solve is the gradient. I really don't understand its source.

Today we had a short spell of a relatively good weather, and I shot the street scene once more:

The result - the same mess

 

[sparedog]

Why it happened? What may cause that? I shot in AVCHD Lite.

i think what you are talking about is the color banding.

i shoot a lot underwater and often see this in the blue backgrounds of the ocean. i think it happens when the gradient has too many tones for the camera codec to handle, even at 4:2:2 so it produces a stepped effect between the colors. it is a common artifact in video, common enough that in nle's like final cut pro there are filters included to try to hide it by adding noise.

the 5d footage is white balanced differently, so maybe the banding isnt showing up due to that. it would be interesting to see when both cameras are set to the same degrees kelvin.

the final video of the apartments, the resolution looks great, i dont think you're gonna get raw 720p looking any better. thats basically what 720p looks like. have you shot with 720p on other cameras and this is what your comparing to, or just 1080? have a close look at the sd being broadcast on tv, and you'll see that your video has much better resolution.

 

[Pipis213]

i think what you are talking about is the color banding.

i shoot a lot underwater and often see this in the blue backgrounds of the ocean. i think it happens when the gradient has too many tones for the camera codec to handle, even at 4:2:2 so it produces a stepped effect between the colors. it is a common artifact in video, common enough that in nle's like final cut pro there are filters included to try to hide it by adding noise.

the final video of the apartments, the resolution looks great, i dont think you're gonna get raw 720p looking any better. thats basically what 720p looks like. have you shot with 720p on other cameras and this is what your comparing to, or just 1080? have a close look at the sd being broadcast on tv, and you'll see that your video has much better resolution.

Thanks, you soothed me I hope this Friday we will do a long studio session with normal light and GF1 I hope that I won't be disappointed with the result.

I haven't directly compared the result of GF1 with other cameras. I had MiniDV 3CCD Panasonic, Sony 1080p. 3CCD camera was good in movements fixation and colour reproducing. But required a lot of light. Sony had the same problem as many other cameras with fast movement, panoraming and etc. The overall quality was so-so.

Here I shot the same scene with a smartphone in 720p:

GF1 gives much better result - obviously.

Thanks!

 

[Pipis213]

Hi everyone!

This weekend we shot a couple of hours in a studio. We used only halogen lights. I used AVCHD 720p 30 frames (29.97) per second.
And I noticed that if I use 1/60 exposure after a couple of second I get a slightly horizontal (from top to down) light strobe. When I changed the exposure to 1/50 I got normal lighting. This is just for your information.

 

[sparedog]

this is to do with the frequency of electricity. this is 100 percent the reason for the different television framerates in ntsc, pal, secam etc
the 1/60 shutter speed is recommended to create a 180 degree shutter angle, however because the camera is only shooting 30fps instead for 25fps, in european countries (and now i learn russia ) you'll get flicker from artificial lighting. so yes, you'll have to use a 1/50 shutter speed with artificial lights, or use specialized lighting.

 

[Dazza]

But he was using halogen lighting which doesn't flicker as it is a form of incandscent lighting,, was there an LCD monitor on in the shot?

 

[Pipis213]

this is to do with the frequency of electricity. this is 100 percent the reason for the different television framerates in ntsc, pal, secam etc
the 1/60 shutter speed is recommended to create a 180 degree shutter angle, however because the camera is only shooting 30fps instead for 25fps, in european countries (and now i learn russia ) you'll get flicker from artificial lighting. so yes, you'll have to use a 1/50 shutter speed with artificial lights, or use specialized lighting.

We used only halogen lights - they are not flickering at all. Even if we had some electronic lamps the frequency would be 50 Hz (such frequency is in Russia for electricity).

 

[Pipis213]

But he was using halogen lighting which doesn't flicker as it is a form of incandscent lighting,, was there an LCD monitor on in the shot?

Yes, we used a notebook screen as a teleprompter unit. But the power of its lighting could lit even the nearest objects. The flickering start after a second or two after beginning of shooting.

It is better to see in 720p. The flickering is visible close to the end of the clip near sides of the frame. In other clips I could see them not only at even coloured surfaces but even at subjects like people.

 

[Dazza]

I've played that clip you posted many times in 720p, and I can't see the flickering you're describing. What sort of flickering is it? Is it a patch?, banding? posterization? What side of the frame is it? left, right, top or bottom? The only thing I noticed is that you've still got some hard shadows from multipoint sources which are a bit distracting to me, a diffuser or larger reflectors would be nice

 

[Pipis213]

I've played that clip you posted many times in 720p, and I can't see the flickering you're describing. What sort of flickering is it? Is it a patch?, banding? posterization? What side of the frame is it? left, right, top or bottom? The only thing I noticed is that you've still got some hard shadows from multipoint sources which are a bit distracting to me, a diffuser or larger reflectors would be nice

Hi!

I also viewed the clip different times including watching it on a big TV and I see the flickering. At the beginning of the clip it is not visible. But a second later I can see light horizontal lines which are running from the top of the frame to its down.
I've tried to capture them as still neighbour frames with later comparison in Photoshop with Difference layers and Couldn't capture the waves. The difference between the frames is too vague.
Then I used a mask and hid a half of top frame and the border became slightly visible:


See the full size photo and at the right. The flickering looks like fast waves from top to down of the screen. The waves are not colour they are of lightness. These waves were visible at the screen of the camera during capturing the clips. After switching the exposure from 1/60 to 1/50 they successfully gone Initially I though that it is ordinary flickering from non incandescent light sources but we didn't have any.

Yes, I agree that the lighting wasn't perfect. We had only two sources 500wt each.

 

[Dazza]

I'm guessing it might be similar to the banding that GH1 users have been experiencing, though it seems less pronounced than that on the GH1.

Glad you found a workaround.

 

[sparedog]

yes i see them, it is in the shaded part of the wall on the right hand side. in my opinion, this is definately due to the lighting frequency, as i have the same artifact in many shots in europe when i set the camera to 1/60. will post something later today with halogen lighting that has the same problem.

 

[Pipis213]

yes i see them, it is in the shaded part of the wall on the right hand side. in my opinion, this is definately due to the lighting frequency, as i have the same artifact in many shots in europe when i set the camera to 1/60. will post something later today with halogen lighting that has the same problem.

I can't understand how a halogen lamp can flicker?
This Friday we had a video session with usage of professional lighting KinoFlo. And I had the same flickering with 1/60 after few seconds from the beginning. 1/50 worked perfectly.