Surprising Lens Options!!
 

Though most of us felt that existing 1/2" SD lenses were not an option to use with the HD100, and wondered why there was a 1/2" to 1/3" step down converter the official HD100 equipment diagram just released by JVC contains some surprises!

The diagram (link below), shows that the ACM-12 step down converter is intended to allow use of the following 1/2" SD on the HD-100: Fujinon S14x7.3, Fujinon S17x6.6, Fujinon S20x6.4, Canon YH16x7, Canon YH19x6.7.

Most of us felt that 1/2" SD lenses would not provide the necessary resolution for HD, and that there would be aliasing problems in using them. Tomorrow at NAB I will ask the JVC reps and reps at the Fujinon booth for a clarification on if these lenses will work adequately on the HD100. I own the Fujinon S20x6.4 and the Fujinon S14x7.3, so I am naturally very curious about this! I'll report my finding here tomorrow.

Link to JVC HD100 equipment diagram: http://www.jvc-victor.co.jp/english/...hd100/sys.html

Our video organization recieved this information a few months ago.

JVC knew nothing about it................WELL.............looks like it is a great reality after all. Guess the rumour was right!!!!!!!!!!!!!!!!

LOU BRUNO

Excellent chart in that link... thanks for sharing this, Steve!

Any word on 1/3" HD prime lenses? I can't even find 1/2" primes for that nifty adapter for HD100 (I think the lens multiplication factor ends up being 1.3x when using 1/2" lens on 1/3" chips). Maybe JVC should have made (or still can make) a 2/3" lens adapter (2x multiplication factor).

Did this page for the GYHD100 System Configuration always have hotspots? Duh, if I missed it before.

http://www.jvc-victor.co.jp/english/...hd100/sys.html

I went back to it yesterday and you can get close ups by clicking on the following:

16x stock lens
13x wide angle
1/2" zoom (not sure which lens this is)
wide converter
1/2" Mount Converter ACM-12
zoom servo control
focus manual control HZ-FM13u (not the one for the 16x)
upper microhphone
battery bn-v4 28u

Don

That page lists several 1/2-inch lens options:

Fuji S14x7.3B12
Fuji S17x6.6BRM
Fuji S20x6.4B12

Canon YH16x7K12
Canon YH19x6.7K12

For the life of me, I can't seem find the stock 1/3-inch Fuji 16x or the wide 13x anywhere on the Fujinon Broadcast site at http://www.fujinonbroadcast.com/

"Did this page ... always have hotspots?"
 

I dunno, but now I feel like a complete idiot. Thanks for spotting that, Don.

Sorry Don! I should have mentioned the hotspot links in my original post. Kinda like an Easter Egg hunt eh...

I have been calling and e-mailing Canon and Fujinon for the past week attempting to get MTF charts for those five 1/2" SD lenses. No luck. The lens makers routinely publish MTF charts for their still photography lenses but refuse to for their broadcast lenses. If we had MTF charts for those lenses we could analyze how well they could resolve images on the HD100. I don't think the Fujinon 14x would resolve high def images, but the Fujinon 20x and Canon 19x may resolve some pretty decent images. If only we could get MTF charts!! I own the Fujinon 20x and it was recently serviced in L.A. by Focus Optics. I have a call in to Focus to see if they did an MTF chart on the lens when it was serviced. If so, I'll post the results. You're right, there is absolutely nothing on the Fujinon web site about the 16x and 13x 1/3" lenses. I've searched the entire Internet, and can't find any info beyond the common info released so far...

Doing some calculations with Graeme, it looks like the lens will need to resolve at least 133 line pairs per millimeter in order to deliver the full resolution possible from the JVC's 1280x720 chip.

The big expensive high-def glass usually only resolves somewhere around 80 to 100 line pairs per millimeter (which is okay, because the 2/3" CCD chip is twice as big/twice as wide, so the lens doesn't need to be so ultra-sharp in order to deliver the full resolution the 2/3" chip is capable of). With the smaller 1/3" chip, and its concordant tinier pixels, the lens has to be substantially sharper in order to deliver adequate resolution. If the lens can only resolve 80 line pairs per millimeter, it won't matter how many pixels you have on your CCD, you'll have soft blurry low-res footage. 80 lp/mm on a 1/3" chip would give you about standard-def resolution, regardless of the CCD pixel count.

So the goal is to find a lens capable of around 133 lp/mm, or 266 lines per millimeter.

Good points! If we had the exact CCD size of the HD100, and MTF charts for the 1/3" 16x, 13x, and MTF charts for the five listed 1/2" SD lenses, we'd be able to make some definitive, but theoretical calculations. Unfortunately, nobody has come up with that data yet. I'm trying every possible way to get those figures. If everyone else trys, someone will come up with the data. The lp/mm of the Fujinon 20x and Canon 19x may be above 80 lp/mm. Getting an MTF chart on them would help answer that. MTF curves are extremely helpful in defining the quality of a lens, but there are other factors:

Schneider White Paper - "The quality of a lens cannot be expressed with a single number or a simple statement. A number of factors must be evaluated in calculating the quality of a lens. Some of these factors include sharpness, contrast, color correction, relative illumination, spectral transmission, and distortion."

To seriously analyze a lens some experts do multiple MTF charts for various points in the lens range. Is there variance among what several experts analyzing a lens see as the lp/mm? Yes, and it can be as much as 30%.

I like theoretical conjecture as much as anyone - but I'm also a big fan of practical field application to prove or disprove the theories. It will be great to get the CCD size measurements of the HD100, and the MTF charts for the 1/3" and 1/2" lenses in question. After that, the proof will be in the testing - in the field putting the camera and lenses through hands on testing in every possible shooting scenario. Then it will be possible to draw some definitive conclusions on the quality of images produced.

Did y'all pick up your hard copy of "HDTV Lens Design: The Canon White Papers" at NAB?

If not, the downloadable PDF versions of the various chapters are available online at www.canonbroadcast.com.

Be sure to check out White Paper #3: HDTV Lens Design: Management of MTF.

The main link is: http://www.usa.canon.com/html/indust...tepapers.shtml

Most of these papers were presented by the esteemed Mr. Larry Thorpe at various SMPTE events... there's some good reading to be done here.

Cine primes are available from Zeiss, Fuji, Canon... but only in the 2/3rd-inch size. Sadly, I really doubt this is going to change. There are only one or two 1/3rd-inch cams that could benefit from these lenses, and they are the HD100 and the Canon XL. Just not enough of a market to justify 1/3rd-inch prime lens design and production, unfortunately.

Thanks Chris! I did get the hard copy of the HDTV Lens Design booklet at the Canon NAB booth - but I haven't read it yet. I will. I'll also check out the info on those other links.

I didn't get the hard copy, but I had read them online, and that's where I got the 80-to-100 lp/mm figures for regular (2/3") lenses...

And we should all keep in mind -- this gives us something to do until the camera comes out, but it's all theoretical. The proof will be when we actually test the darn thing. If it looks great, I won't care whether the MTF or lp/mm hold up! ;)