View Full Version : HVX Res Charts in every format


Luis Caffesse
January 11th, 2006, 11:00 AM
Thanks to Mike Curtis at HDforIndies (www.hdforindies.com)
I was able to do some shooting with the HVX a while back.
One of the things we did was shoot a res chart in every format the camera had to offer.

I've pulled stills from each clip and put them up on my site - though I'm not sure how long my bandwidth will last. Chris - Mike mentioned that you might be willing to host these here at DVinfo - if so that would be great, just let me know.

The charts probably shouldn't be used to compare with other charts from other cameras - the only way I think you can do a real cam to cam comparison is to have the same person shoot the same chart at the same location with the same settings, etc. But, I found these charts great to compare each format against the others from the HVX.

The settings were as follows (unless noted otherwise by the file name):


FStop: 4.0

Zoom: Z74

Gain: ZERO

Detail: ZERO

Gamma:
HDNorm (for HD shots)
SDNorm (for SD shots)

All other settings were at factory defaults.

You can check out the charts here (until I find a better place to host them)

[EDITED TO REMOVE LINK - SEE BELOW]

The files are in TIFF format
I also uploaded a zip file that contains all the TIFFs so you can just download that if you want to see all of them.

Mike Marriage
January 11th, 2006, 11:07 AM
That's great, cheers!

Clearly presented too. :)

Luis Caffesse
January 11th, 2006, 11:23 AM
On another board Juan (of Andromeda) pointed out that the charts were shot such as to give a better reading than they should have had -

I don't want to mislead anyone, so let me make it clear:

These charts should not be considered to be a rigid test, but a gauge to view the formats in relation to one another. I wouldn't pull any numbers from this.

By the time we got around to shooting charts we were running out of time with the camera.
I didn't notice the framing until we were through about half of the formats...and didn't really have the time to go back and start over. I felt at that point it woudl be best to leave things as they were, and at least have a relative guide of each format against the others that the HVX offers. While you can't pull objective numbers from it to compare to other cams, I think you can still use these images to compare 1080P to 720P for example (which I found interesting).

I would wait until Barry's side by side test to see any objective readings that we can compare against other cams. So again, take this for what it is.

AGAIN -
DO NOT PULL NUMBERS FROM THESE CHARTS
They should be viewed to compare the formats within the camera.
NOT to compare the HVX to other cams.

Personally, I still feel that is usefull.

While the charts are not objectively accurate, they are consistent.

Luis Caffesse
January 11th, 2006, 11:25 AM
Well that didn't last long did it?

After only a few minutes - people were trying to pull number off the charts as opposed to viewing them for what they are.

I suppose I can't blame them.
I've pulled them offline because I don't want to be responsible for misinformation.

Mike Marriage
January 11th, 2006, 11:29 AM
Yeah, the charts are pretty cropped. Anyhow, it does seem to show a resolution increase between 720p and 1080p. 1080 goes off the scale whereas 720 barely reaches it. It is particular noticeable horizontally.

Antoine Fabi
January 11th, 2006, 11:37 AM
thanks a lot Luis.

Are these grabs after they've been capture by the DVCPro HD codec or direct from the camcorder ?


...anyway...i always felt the camera was showing good resolving power from some footage i've seen so far.

...the images are croped vertically, but not horizontally...and yes, it is usefull to show the HVX is powerfull.

You're right, i wouldn't draw any numbered conclusions based on that, but there is something very very shure though...
those grabs "look" A LOT sharper (resolving power) and cleaner than the other ones i had seen.

Michael Pappas
January 11th, 2006, 02:31 PM
Luis,

Can I ask how this happen though. Run and gun or not, filming charts is DoP 101. The arrows or frame guide points on charts are there to frame around. It's quite simple.... Why did this happen?

It was like when Kaku did his res test. Luckily I was on ichat and he contacted me. He didn't know how to film the charts, so i best explained to him how it's done in ichat. The charts from Shannon and Nick were off. Actually I expect Nick to had done that spot on more than Shannon since Nick is a tech.

If we are going to use measurements to derive numbers and performance specs for comparisons, everyone must follow the guide lines set forth for testing so there is a good fundamental constancy between all tests. This is true in any industry.

Michael Pappas


Well that didn't last long did it?

After only a few minutes - people were trying to pull number off the charts as opposed to viewing them for what they are.

I suppose I can't blame them.
I've pulled them offline because I don't want to be responsible for misinformation.

Luis Caffesse
January 11th, 2006, 03:07 PM
"If we are going to use measurements to derive numbers and performance specs for comparisons, everyone must follow the guide lines set forth for testing so there is a good fundamental constancy between all tests. This is true in any industry."

I couldn't agree more Michael.

It happened due to both a rush and lack of attention on my part.
I didn't check the framing until we'd gone through about half of the formats (I wasn't shooting at the time). By the time i realized the chart was way off, I figured it was best to just keep going so we coudl get shots of everything and they images could at least be used as a reference against eachother (meaning the charts still serve to compare the different formats within the HVX, but not to derive any numbers from).

Like I said, I pulled them because people seemed to be taking the wrong idea from them, and I suppose I can't blame them.

So, it most partly time and partly just lack of attention.
We spent most of the day shooting footage outside, which is what I would personally rather see - looking back we probably should have shot the charts first, since that is what seems to be more important to many people.