Huh? Any movement or slanted lines shown using pairs of identical fields will definitely NOT be the same as progressive.

Sorry but I don't agree with this. At a 1/30th setting, an image is recorded for 1/30 of a second into an electronic buffer. The chip then refreshes and records for another 1/30th of a second. There is simply no temporal "gap" in recording to cause the kinds of problems you are referring to.

The 1/30th exposure is then send to two 1/60th fields ... thus as DSE says, resolution is roughly halved and it has (obviously) a characteristic 1/30th second shutter blur - this will limit the usefulness of the footage for most people.

Sorry but I don't agree with this. At a 1/30th setting, an image is recorded for 1/30 of a second into an electronic buffer. The chip then refreshes and records for another 1/30th of a second. There is simply no temporal "gap" in recording to cause the kinds of problems you are referring to.


To paraphrase Douglas Spotted Eagle, this horse is dead.

The same data is recorded for each field. The data from field one does not actually belong in field two, so it ends up being spatially incorrect. However, it can be good enough to trick the eyes and blur hides a lot of the stepping of lines (It will be quite unnoticeable if down-converted to SD). But it never will be the same as an image from a progressive camera.

But, it doesn't really matter. If you like the look, use it.

But one doesn't render back to fields - the aim is 30P. So the 'single field' image expands to fill the frame, and similarly the 1/30th time interval. Resolution is lost (as everyone agrees) but quite simply there are NO stepping lines.

I apologise for going on about this for so long, but it's frustrating that people keep making this statement.

I own an HC1. I have shot footage at 1/30 and with the cinema effect before. I've even recommended the cinema effect as a creative alternative in posts on this board and I feel that if you like the footage from it or 1/30, then that is great. However, I have seen stepping that kind of shrinks and grows and changes shape on angled lines with movement --- subtle but definitely there. But apparently you have not seen this and feel that the HC1 produces progressive footage with no interlace artifacts. That is excellent. I really have nothing more to add to this topic.

However, I have seen stepping that kind of shrinks and grows and changes shape on angled lines with movement --- subtle but definitely there. But apparently you have not seen this and feel that the HC1 produces progressive footage with no interlace artifacts.

Oh dear, did you even read this thread?

The hc1 encodes those fields improperly on the hc1 using a shutter of 1/30, that's why there are lines. There should not be and they are easy to remove with a field swap ending with a progressive frame. If you use an interlaced monitor to watch your material you won't notice the swap, but progressive monitors will show it. Try 1/4th shutter for an example of a properly coded frame.

Here's a clip where I had some problems with those low shutter interlace artifacts, but I managed to remove them. Light was occasionally very low so a 1/25 shutter was necessary. Noise was absolutely overkill in some shots. Encoded with divx.

http://hmcindie.pp.fi/movies/Fantasy%20klub%20divx.avi

The data from field one does not actually belong in field two, so it ends up being spatially incorrect.

What's wrong here? We are talking about lower shutter speeds than the standard 1/60 so there won't be any spatial incorrectness.

Graham's explanation is correct.

The same kind of interlace swap can be seen in some movies / tv series that have been transferred from film to video. 25 fps which is correct here in pal, but some scenes can have swapped fields if done improperly. That means when viewing the material on a progressive monitor it will show fields in some scenes, eventhough the material is progressive at 25 fps. Interlaced tv's still show them right (because the fields are still the same).

Is the material interlaced when there are interlace lines eventhough it's in reality 25p?

I really don't even care if the camera has lower resolution when using a 1/30th shutter. To me a clean looking image is what matters and I can tell you that this trick makes some very clean looking images. I have shot dozens of samples and so far none of them show any interlaced or aliased lines at all. Angled edges are clean as they are in progressive images. There is also more going on here then just field blending. With field blending you can since the half and half blended frames during a freeze frame of an object in motion. It will look like ghosting. With the 1/30th shutter the same type of motion with look like real motion blur where the blur has a gradient that blends into the solid part of the object and not just a half transparent object blended on top. It looks exactly how animation looks when rendered in After Effects with a motion blur level of 360 degrees. Yes things are very blurry but it does seem to be a natural blur and the image seems perfectly clean.

I know this isn't the way we are all used to slower shutter speeds but then again this camera is pretty unique all around. Again, I am not going to shoot a resolution chart because I could care less how many lines the camera resolves. All I want is a clean image which so far it seems to do very well.

Would I use the 1/30th shutter? Most likely no. That is because I do not like 30p but prefer 24p or 25p. Now if somebody has a PAL HC1 they may be able to use this trick for some great stuff that could be retimed by 4% to 24p. I retimed some of the 1/30th stuff to 24p and it looks nice. It is a little blurry but it looks nice.

I'm really glad to see this discussion. Some may say this topic has been beaten to death but then there is a reason why it keeps coming up. If you are somebody who doesn't like to use the camera in that way then don't use it that way. Nobody is forcing you to use a shutter of 1/30th. If somebody can find some great use for this trick then I am glad it works for you. The great thing about art is that there isn't supposed to be any rules. Nobody would tell Andy Warhol that he isn't using his paint brush the correct way. There are some that may say video isn't supposed to be artistic and there are set rules but I do not agree with that. There are two schools of thought here. One is the commercial aspect of video where it needs to be done a certain way to make money. The other way is an artistic movement that views video as a artistic medium where rules can change and we are only limited by our imagination. Every now and again somebody will use these new tools to break the rules and create something nobody thought of before. After that everybody tries to copy that new method forgetting what it means to experiment with the camera and come up with their own style and own set of rules. Just watch out. Who knows. Maybe someday somebody will use a PAL HC1 to create a movie for Sundance using a 1/25th shutter and people will love it.

Hi chaps

just wanted to let you know that I have the PAL Canon HV10 and in shutter priority 25 is does indeed appear to shoot progressive - there are no horizonatal artifacts and the image is good - particularly useful in low light/outdoor shots. There is of course some blurring compared to shutter 50. I would also point out that in my opinion (viewed on 24 inch CRT 1920x1200 Sony FW900 monitor) there is some loss in resultion and infact material shot with higher shutter speeds looks sharper when played back in VLC using the BOB deinterlace function. Having said that 25 is really sueful and does have a certain look.

I have posted some samples in the HV10 forum but am happy to post some here if anyone wants to see what the same scene in 25 v 50 looks like

Cheers
Fergus

Hi,

For those interested in HC1's 30p trick, i found something interesting:

1. Shoot with shutter speed at 1/30.
2. Easy-setup FCP 6 to 1030p30 basic firewire
3. Capture the footage.
4. Put it on a new 1080p30 sequence and click "no" when FCP asks to reset to 1080i60.
5. Edit (if you want to)
6. Export to quicktime movie HDV 1080p30 and watch the results in a progressive monitor.

I don't know exactly what is happening in this process, but as far as I can see (please tell me if I'm wrong) the resulting footage is clean full resolution 1080p30.