Canon Lens Breathing
 

[QUOTE=Robert Lane;682653] Once back-focus was set it had minimal to almost no breathing when zoomed and otherwise performed very well considering it's price-point and intended usage. Based on my experiences with similarly priced Fuji lenses - and if I wanted one of the kit lenses - I would purchase that Canon, hands down.


According to Barry Green's excellent article on the 500 on another site, the Canon cac 2x lens exhibited a lot of breathing typical of the new "economy priced" hd lenses.
Lens "breathing" is the image size shifting that occurs when changing focus; looks a little like you're zooming when you're not. Most noticable on extreme focus changes on a static shot. More expensive lenses tend to better correct this optical phenomenon.
Experienced operators will try to hide/minimize lens breathing by panning/zooming the camera during the shot.
You can test your own lenses breathing characteristics by racking focus from near to far at various focal lengths w/o zooming .
The cac series of lenses are so new that I can't find any specs for them, like weight, filter sizes, matte box fittings , etc.

I don't find breathing a major problem for ENG/EFP work because you don't tend to pull focus much during the shot. It is obviously more critical for digital cinema work though.

Chris: I was able to get weight, minimum focus distance and angle of view by going to B&H (although I ordered my camera from Able's), picking the HPX500 package I want, going to the ITEM COMES WITH tab and clicking on the lens supplied - this works with the Canon lenses at least... In my case, the 16x w/o 2x is 3.2 lbs and focuses (w/o resorting to Macro) to 2 ft, both of which are good for my style of shooting...

As for breathing - I hate it, and I do do things like pan or move when I follow focus, even when shooting documentaries.. nothing says crumby zoom lens like a significant change in image size during a focus change.. That is why I wish there was a short zoom available, they're less likely to show breathing... But, hey, these lenses are way cheap, and if they work otherwise, I'll live with it...

Jimi,

The two main differences are that the Varicam is a tape-based workflow which will cost you more time in capture operations and more in media costs; the Varicam is a native HD chipset and will render cleaner and slightly sharper images. There are a host of other less critical differences but those are the ones that could be a deal-breaker either way depending on what your needs are.

I couldn't recommend one above the other for you because I know nothing of your production needs, shooting style, budget or size of your production crew. I will say however, that ever since we became a P2-only production company that there would never be a reason for us to consider the Varicam as proven by our 1.5 years shooting the HVX200.

You'll have to weigh-out the differences between the two and decide which is best for your needs, but just understand they are two very different platforms with albeit very similar capabilities.

It'll be interesting to see a direct comparison.

I would guess that there will be very little in it as the Varicam is limited to the 960x720 of DVCPROHD 720p. I would guess that the HPX500 could match that and possibly even resolve slightly more in 1080p. Purely speculation though.

The HPX500 will hopefully be less noisy too, with larger pixels and newer technology.

cac lens specs
 

Steve,
Thanks for link to B&H site for the lens info. Hope it's accurate as they also list a headcleaning tape as an accessory !!!
Like a lot of video lenses, HD or SD, notice that the max. lens aperture doesn't hold all the way thru the zoom range. IOW, lens must be stopped down at least a stop (or more) for an evenly exposed zoom shot from full wide angel to full tele. Another compromise, but the price is right.
Some of my savvy clients will request better glass (and pay for it) while others will opt for even SD glass because it is "good enough"(and cheaper). Depends on the job or needs of client.
I've never shot video for a film out, just film , but I would favor the best HD glass possible for the project.

Yeah, I noticed that head cleaner too.. maybe they mean our heads.. But, no, the info comes from Canon - The thing that does concern me is that the weight for both the w/2x and the w/o2x are the same, and that can't be right...

I'm with you about lenses, but the great thing is that as time passes, affordable lenses will be more available...

Thank you Robert,
I see what you mean.If they look close to each other on big screen I would go with 500 for the reasons you wrote.
I just hope it will.
Best regards.
Jimi