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-   -   Hardest time deciding on EX1 over HVX200a (https://www.dvinfo.net/forum/general-hd-720-1080-acquisition/137514-hardest-time-deciding-ex1-over-hvx200a.html)

David Chapman November 10th, 2008 11:04 AM

Hardest time deciding on EX1 over HVX200a
 
Hey guys,

I have been having the hardest time weighing the pros and cons of the EX1 and the HVX200a. I didn't realize until recently that the CMOS censors might be a huge hiccup in my shooting. I have come across an interesting clip of a police car that looks absolutely horrible with the half to 2/3 frame being flashed and the rest dark. The skew on pans also worries me a little bit.

I mainly do special effects that requires tracking points in frame, match moving for matte paintings, or keying. I also shoot on set effects like small pyrotechnics and sparks from a welding torch. Is the EX1 going to fall short in these areas?

Downside to HVX200a: expensive p2 cards, not full frame video, but squeezed (1280x1080 stretched to 1920x1080).

Perrone Ford November 10th, 2008 11:44 AM

I love my EX1, but if I was shooting what you are, I'd probably be looking at a different cam. Why the 200A over the new HPX170?

Alister Chapman November 10th, 2008 12:01 PM

While camera flashes and certain types of strobe lighting can cause the split frame effect you have seen it should also be remembered that CCD's can suffer from smear with strong lighting so there are pro's and con's to both.

Skew is only a problem with very fast pans and in that case the pan is likely to be so fast that the subject is going to be blurred anyway. If you do a lot of compositing then having square pixels without any aspect stretching should make your life a lot easier.

I love the pictures from my EX1. Despite having a more expensive F350 XDCAM HD camcorder along with HD lenses, expensive batteries etc. My camera of choice is normally my EX3 because the picture quality from it is so good, even in low light. Picture quality from the EX1 and EX3 is exactly the same.

EX advantages are: Full Raster, Full resolution, high sensitivity, low noise, cheaper media (even cheaper if you use SD cards), better LCD, proper focus ring.

David Chapman November 10th, 2008 02:10 PM

I agree the the picture quality and full size HD frame is better than the pixel resizing. I just saw some videos like the one below and got a little worried.

Sony PMW-EX1 Skew and Wobble Test on Vimeo

The fence panning is a little slower towards the end and it still has visible skew.

Bob Kerner November 10th, 2008 08:21 PM

I've wondered the same thing but, in reality, are you ever going to pan like that? Or run down the street with your camera? These tests can be frustrating to look at because they're purposely set up to exploit expected weaknesses in the technology.

Rent it and see how it performs under your conditions. I just stumbled upon a video journalist's site and he's using the EX-1 in combat zones. That's convincing enough for me but I'm still gonna rent to see if it meets my needs.



Quote:

Originally Posted by James Chapman (Post 961851)
I agree the the picture quality and full size HD frame is better than the pixel resizing. I just saw some videos like the one below and got a little worried.

Sony PMW-EX1 Skew and Wobble Test on Vimeo

The fence panning is a little slower towards the end and it still has visible skew.


Michael Kraus November 10th, 2008 09:29 PM

Quote:

Originally Posted by Perrone Ford (Post 961794)
Why the 200A over the new HPX170?

James I am curious as well as to why you are considering the 200a over the 170?

David Chapman November 10th, 2008 11:00 PM

@Michael Kraus

People are complaining about lens wobble and the cheap feeling of the smaller 170. The sensors for the HVX200a are now the same and I don't know if I would ever use the HD-SDI out of the camera. The image flip doesn't matter to me since I'm getting a Letus Extreme that flips the image anyways and who really knows how the 170's histogram will really help on a small screen.

Check out the wobble here:
HPX170 Lens Wobble Remedy on Vimeo

Michael Kraus November 11th, 2008 07:00 PM

thanks for the response james. i'll be looking into it :)

David Chapman November 12th, 2008 11:31 PM

I think I have finally decided on the EX1 over the HVX200a. Why?

Although the EX1 does shoot HDV at 4:2:0, it is higher bit rate than my JVC HD100 that I just sold and gave me great shots and good keys. I tracked panned footage and did a whole year of effects on the native HDV 720p24 format.

The 2 scares I had that put me on the fence between both cameras was the EX1's rolling shutter (image skew on fast pans and half exposures of some strobe lighting) and the non-full frame image on the HVX200a (960x540 stretched to 1920x1080). The pros would have been a full frame sensor in the EX1 and the CCD instead of the CMOS in the HVX.

From all of my research, I have seen that the skew only happens on fast pans which would look bad anyways and the half exposure on strobes can have workarounds to solve. Come to think of it, film cameras and the RED ONE have rolling shutters. I would much rather be working on full frame video than a stretched version with 4:2:2 color sampling (HVX). The EX1 would allow me to capture the full frame 4:2:2 color out via HD-SDI, which the HVX has component only.

Philip Bloom was the biggest seller to me for this camera. He has had both and loves the EX1.

Alister Chapman November 17th, 2008 03:27 PM

Glad you were able to make a choice.

The XDCAM EX codec while similar to HDV is most definitely NOT HDV. It is not just a higher bit rate but it is also a variable but rate which deals with rapid changes in picture content better than HDV. If you switch an EX between the HDV compatible SP mode and HQ mode the difference is very noticeable.

Forest Finbow December 10th, 2008 08:55 PM

I totaly agree with the fact that the 35mbps XDCAM EX HQ bitrate is superior to HDV coding, but AFAIK the whole VBR thing is more about bitrate saving than actual quality improvement. The thing is, in order to improve the picture quality, the encoder should need to know how the motion will actualy be further down the shot, which of course it can't, since it is working in real time.

What actualy happens (and you can double check if you make some analysis of coded contents) is that the stream will stick to 35 mbps if the encoder encounters high compexity (sort of in a 35 mbps CBR way, without the padding) and actualy drops down a couple mbps in case of low compexity (as low as 31 mbps in my tests). That still is a smart way of coding motion, along with the whole long gop algo, but it should not be mistaken with a 35 mbps targeted 2 pass encoding with 20 mbps min and 50 mbps max that would effectivly optimize quality over the motion.

I might me mistaken, and actualy would be happy to be proved wrong, the encoder might actualy feature some sort of buffering in order to have some some space for motion estimation, but I'm afraid that if any buffering there realy is, it would to short to really achieve the quality improvement expected from a real VBR algorythm.

Steven Thomas December 15th, 2008 09:19 PM

I have not seen anything less than 35mbps and peaking around 40mbps.
Maybe it was due to the level of detail at that those times.

Forest Finbow December 16th, 2008 03:10 AM

That's weard, given Sony has always stated the 35mbps where actual the maximum bitrate. Are you shure you haven't been measuring the multiplexed bitrate, mpeg2 vidéo + uncompressed sound ?

Simon Wyndham December 22nd, 2008 05:28 PM

Quote:

I just saw some videos like the one below and got a little worried.
The fence skew is very noticeable, but as others have said, do you really use a camera like that? As for the running handheld shot I'm not sure what the issue is. Maybe I'm just blind but I can't see any wobbling other than the fact that is a very wobbly handheld shot.

Steve Wolla December 29th, 2008 12:31 AM

Why not rent an EX-1 and a HPX 170 or 200a and take them on typical projects that you shoot? That would give the best clue as to which is really best for you. That's the real test, seeing what works best for you in the field, on the job.


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