Slow mo settings question at DVinfo.net

Alan James · August 6th, 2006, 06:06 PM

I am going to be using the FX1 to shoot some slow mo stuff (it can be done) then convert it to DVD quality. To ask my question I think I have to explain how I’m going to do this. I’m gunna shoot 60i then in post switch between even and odd lines to make a progressive image that is 540 pixels tall. Then I’m gunna take that and shrink it to 480X864 to put into my editor. Okay now to my question. What setting should I use to shoot this? Ex: should I shoot in 4X3 or 16X9. Which is going to give me the best image being that I will down convert it? I know in 16X9 the pixels are 1.33 wide and in 4X3 they are square, but it uses less of them. I have also heard that the FX1 has CCDs measuring 960X1080, then the image is unconverted to HD. Anyways lots of technical questions. Hope someone can help.

Dylan Pank · August 7th, 2006, 06:18 AM

You can ONLY shoot HD at 16:9 with 1.33:1 pixels. There is no other mode. 4:3 Square-ish pixels (they're actually slightly rectangular) is SD DV only.

The FX1 does have CCDs of 960pixels across, but that's still more than widescreen DVD resolution so it shouldn't be an issue. Anyway, the Sony 3CCD HDV cams use pixel shift (ie the CCDs are slightly out of alignment) to create extra horizontal res'. How effective that is up for debate, but at DVD resolution it's all moot.

One tip, if you're shooting in enough light, set the shutter speed to 120th/sec. The slow mo should be a little sharper and less blurred, as the shutter speed will match that of a film camera shooting at 60fps.

Tom Hardwick · August 7th, 2006, 06:49 AM

I put a lot of my Z1 footage into slo-mo, using the Canopus Speed Controller program and Premiere. I always use the default 1/50th sec shutter speed (PAL) as using this means you capture everything that happens in front of the lens.

If you set 1/120th sec as Dylan suggests you'll have lost half of life as it passes your lens, and in slo mo this will become painfully obvious. OK, there will be less subject and camera blur, but as slo-mo has such a smoothing capability about it, this hardly matters.

tom.

Dylan Pank · August 7th, 2006, 09:02 AM

Every. Single. Slow Motion Shot. EVER done on film would have been done in such as way as to "lose half of life", what so it's up to you. Also anyone who has every de-interlaced 60i footage is also doing the same thing again.

Personally I feel that slow mo with the faster shutter speed more accurately replicates the motion signature of progressive scan and film, it seems more realistic. Additional motion blur at 25fps playback to me is very noticable and has a video-effectish look. I prefer the far more natural look of a faster shutter speed.

What I mean is, shooting 50% slow motion with a 60/sec shutter speed is exactly the same as shooting regular motion with a 25th/sec shutter (assuming PAL). If you like that look, go ahead, knock yerself out!

I guess Alan should test both approaches and see what he prefers.

Tom Hardwick · August 7th, 2006, 09:22 AM

I agree with you when you say Alan should conduct some tests to see which he prefers, and this is something video is very good at.

And I also agree that film fails to record half of life - if only because historically frame pull-down requires a 180 degree (or thereabouts) shutter. So yes, progressive and high shutter speeds do replicate the film signature in video slo-mo, though I don't see Alan asking for this look.

When you get down to very slow rates (like 15% speed, say) then the missing time slots that come from shooting at higher than standard shutter speeds begins to look odd. Interpolation to the rescue.

tom.

Alan James · August 7th, 2006, 08:05 PM

I will be shooting 60i then turning that into 60p then put that into a 24p timeline. Thanx for all of the help. I think my best plan is to use a 1/60 shutter speed and then play around from there. The only reason I asked this question is because I don’t have an FX1 but I will be using my friends in a few weeks to shoot with. Again thanx for the help.

Mikko Lopponen · August 9th, 2006, 02:46 PM

I shoot even regular stuff at 1/120 shutter, so I guess I should shoot slowmotion at about 1/240 :)

August 6th, 2006, 06:06 PM	#1
Alan James Regular Crew Join Date: Jul 2006 Location: Tampa, Florida Posts: 261	Slow mo settings question I am going to be using the FX1 to shoot some slow mo stuff (it can be done) then convert it to DVD quality. To ask my question I think I have to explain how I’m going to do this. I’m gunna shoot 60i then in post switch between even and odd lines to make a progressive image that is 540 pixels tall. Then I’m gunna take that and shrink it to 480X864 to put into my editor. Okay now to my question. What setting should I use to shoot this? Ex: should I shoot in 4X3 or 16X9. Which is going to give me the best image being that I will down convert it? I know in 16X9 the pixels are 1.33 wide and in 4X3 they are square, but it uses less of them. I have also heard that the FX1 has CCDs measuring 960X1080, then the image is unconverted to HD. Anyways lots of technical questions. Hope someone can help.

August 7th, 2006, 06:18 AM	#2
Dylan Pank Major Player Join Date: Nov 2004 Location: Portsmouth, UK Posts: 611	You can ONLY shoot HD at 16:9 with 1.33:1 pixels. There is no other mode. 4:3 Square-ish pixels (they're actually slightly rectangular) is SD DV only. The FX1 does have CCDs of 960pixels across, but that's still more than widescreen DVD resolution so it shouldn't be an issue. Anyway, the Sony 3CCD HDV cams use pixel shift (ie the CCDs are slightly out of alignment) to create extra horizontal res'. How effective that is up for debate, but at DVD resolution it's all moot. One tip, if you're shooting in enough light, set the shutter speed to 120th/sec. The slow mo should be a little sharper and less blurred, as the shutter speed will match that of a film camera shooting at 60fps.

August 7th, 2006, 06:49 AM	#3
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	I put a lot of my Z1 footage into slo-mo, using the Canopus Speed Controller program and Premiere. I always use the default 1/50th sec shutter speed (PAL) as using this means you capture everything that happens in front of the lens. If you set 1/120th sec as Dylan suggests you'll have lost half of life as it passes your lens, and in slo mo this will become painfully obvious. OK, there will be less subject and camera blur, but as slo-mo has such a smoothing capability about it, this hardly matters. tom.

August 7th, 2006, 09:02 AM	#4
Dylan Pank Major Player Join Date: Nov 2004 Location: Portsmouth, UK Posts: 611	Every. Single. Slow Motion Shot. EVER done on film would have been done in such as way as to "lose half of life", what so it's up to you. Also anyone who has every de-interlaced 60i footage is also doing the same thing again. Personally I feel that slow mo with the faster shutter speed more accurately replicates the motion signature of progressive scan and film, it seems more realistic. Additional motion blur at 25fps playback to me is very noticable and has a video-effectish look. I prefer the far more natural look of a faster shutter speed. What I mean is, shooting 50% slow motion with a 60/sec shutter speed is exactly the same as shooting regular motion with a 25th/sec shutter (assuming PAL). If you like that look, go ahead, knock yerself out! I guess Alan should test both approaches and see what he prefers.

August 7th, 2006, 09:22 AM	#5
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	I agree with you when you say Alan should conduct some tests to see which he prefers, and this is something video is very good at. And I also agree that film fails to record half of life - if only because historically frame pull-down requires a 180 degree (or thereabouts) shutter. So yes, progressive and high shutter speeds do replicate the film signature in video slo-mo, though I don't see Alan asking for this look. When you get down to very slow rates (like 15% speed, say) then the missing time slots that come from shooting at higher than standard shutter speeds begins to look odd. Interpolation to the rescue. tom.

August 7th, 2006, 08:05 PM	#6
Alan James Regular Crew Join Date: Jul 2006 Location: Tampa, Florida Posts: 261	I will be shooting 60i then turning that into 60p then put that into a 24p timeline. Thanx for all of the help. I think my best plan is to use a 1/60 shutter speed and then play around from there. The only reason I asked this question is because I don’t have an FX1 but I will be using my friends in a few weeks to shoot with. Again thanx for the help.

August 9th, 2006, 02:46 PM	#7
Mikko Lopponen Major Player Join Date: Mar 2006 Location: Helsinki, Finland Posts: 393	I shoot even regular stuff at 1/120 shutter, so I guess I should shoot slowmotion at about 1/240 :)