Vidcaps

George Yousko · September 8th, 2006, 07:51 PM

Have a Z1. The question is - just how good are the HD "vidcaps" (still images with perhaps some Photoshop magic applied if needed) in comparison to true digital photos. Has it become a close second? If not, how much of the gap have we filled? Anxious to get some feedback on this issue.

George

Boyd Ostroff · September 8th, 2006, 08:22 PM

They aren't bad, certainly better than still frames from standard definition DV. But there are a couple problems. First, it's interlaced video so if things are moving you will get jaggy edges. Second, HDV 1080i is anamorphic; it's 1920x1080 which has been squeezed to 1440x1080. So if you want the best quality you will need to downsample the images to 1440x810 or so. To get rid of interlace artifacts you will either need to deinterlace or downsample further.

From my experience, the stills look a little soft unless you downres them to (maybe) 1280x720. Now that is only the equivalent to a 1 megapixel still, so I'd say the gap between still frames and digital still photos is pretty substantial given the pixel count of most current still cameras. But like they say, "your mileage may vary." It has a lot to do with the nature of the footage you're grabbing frames from. But my observation would be that the Z1 is no match for a digital still camera in most cases.

Kevin Shaw · September 8th, 2006, 08:52 PM

My first digital still camera had a resolution of 640x480 pixels; HDV yields at least twice that after deinterlacing but falls well short of today's digital cameras. The results look 'videoish' yet are much more useful than typical DV frame grabs; you can make prints up to 8x10 which will look acceptable to most casual viewers. I frequently use HDV frame grabs now for DVD artwork and web site samples, and that usually works out okay.

George Yousko · September 8th, 2006, 09:13 PM

Never went through the process but you have both fill in the missing blanks as to knowing what to expect - thanks for putting me on the fast track. Nice to know that if Mars and Jupiter are aligned just right and the moon is full.....

George

Mark Utley · September 8th, 2006, 11:33 PM

I shot a couple of my friends' bands yesterday who were playing an outdoor show. Here's a raw frame and the same one scaled down and colour-corrected (both deinterlaced):

1920x1080, normal: http://www.mumps.ca/pictures/VIC_full.jpg
500x281, CC: http://www.mumps.ca/pictures/VIC_mitch.jpg

The shutter speed was 1/60 and the camera was moving a bit so it's somewhat blurry.

George Yousko · September 9th, 2006, 03:08 PM

Hey Mark,

That's not bad - REALLY! It's a dramatic improvement over SD and granted a "true digital photo" would of course yet be even better. All things considered that's quite a ways down the road from where we came from. Suspect as was pointed out it would generate a 8 x 10 quite nicely. Thanks for sharing

George

September 8th, 2006, 07:51 PM	#1
George Yousko Regular Crew Join Date: May 2005 Posts: 38	Vidcaps - The quality is.... Have a Z1. The question is - just how good are the HD "vidcaps" (still images with perhaps some Photoshop magic applied if needed) in comparison to true digital photos. Has it become a close second? If not, how much of the gap have we filled? Anxious to get some feedback on this issue. George

September 8th, 2006, 11:33 PM	#5
Mark Utley Major Player Join Date: Mar 2004 Location: Toronto, ON, Canada Posts: 479	I shot a couple of my friends' bands yesterday who were playing an outdoor show. Here's a raw frame and the same one scaled down and colour-corrected (both deinterlaced): 1920x1080, normal: http://www.mumps.ca/pictures/VIC_full.jpg 500x281, CC: http://www.mumps.ca/pictures/VIC_mitch.jpg The shutter speed was 1/60 and the camera was moving a bit so it's somewhat blurry. __________________ Mark Utley

September 8th, 2006, 08:22 PM	#2
Boyd Ostroff Wrangler Join Date: Dec 2002 Location: Mays Landing, NJ Posts: 11,802	They aren't bad, certainly better than still frames from standard definition DV. But there are a couple problems. First, it's interlaced video so if things are moving you will get jaggy edges. Second, HDV 1080i is anamorphic; it's 1920x1080 which has been squeezed to 1440x1080. So if you want the best quality you will need to downsample the images to 1440x810 or so. To get rid of interlace artifacts you will either need to deinterlace or downsample further. From my experience, the stills look a little soft unless you downres them to (maybe) 1280x720. Now that is only the equivalent to a 1 megapixel still, so I'd say the gap between still frames and digital still photos is pretty substantial given the pixel count of most current still cameras. But like they say, "your mileage may vary." It has a lot to do with the nature of the footage you're grabbing frames from. But my observation would be that the Z1 is no match for a digital still camera in most cases.

September 8th, 2006, 08:52 PM	#3
Kevin Shaw Inner Circle Join Date: Sep 2004 Location: Sacramento, CA Posts: 2,488	My first digital still camera had a resolution of 640x480 pixels; HDV yields at least twice that after deinterlacing but falls well short of today's digital cameras. The results look 'videoish' yet are much more useful than typical DV frame grabs; you can make prints up to 8x10 which will look acceptable to most casual viewers. I frequently use HDV frame grabs now for DVD artwork and web site samples, and that usually works out okay.

September 8th, 2006, 09:13 PM	#4
George Yousko Regular Crew Join Date: May 2005 Posts: 38	Never went through the process but you have both fill in the missing blanks as to knowing what to expect - thanks for putting me on the fast track. Nice to know that if Mars and Jupiter are aligned just right and the moon is full..... George

September 9th, 2006, 03:08 PM	#6
George Yousko Regular Crew Join Date: May 2005 Posts: 38	Hey Mark, That's not bad - REALLY! It's a dramatic improvement over SD and granted a "true digital photo" would of course yet be even better. All things considered that's quite a ways down the road from where we came from. Suspect as was pointed out it would generate a 8 x 10 quite nicely. Thanks for sharing George