primes

[Ray Van Eng]

To use zoom as a framing device and not calling attention to itself is the right approach I would say. For wedding and event coverage in which there is no second take or you have your camera on a tripod, I would agree that a zoom is invaluable (or even indispensable), both as a framing device and for creating a sense of capturing reality as it happens. But even here I would go for a short range zoom if available. You'll be amazed what such a lens can do for you if you learn how to anticipate your live action a little better. The end result will show your professional intelligence much more convincingly than a whole load of shifty zoom actions. To me, you cannot claim that you use zoom heavily because the action happens to fast and is too hard to predict. Learn how to pick your position, angle and the use of a certain focal length.

People talk about the film look a lot, but part of the mystique of a celluloid feel is having the camera 'contains' the action with just one focal length doing a long take. Whatever action that happens stays inside the frame. That can be done with video too.

As for barrel or pincushion distortions, practically any zoom lens would have a certain degree of that. That's part of the reason why some of us like primes.

[Jon Bickford]

a couple of years ago i saw Martin Scorsese speak at the DGA and one of the points he made was that when he was in film school camera movement was difficult so you had to have a good reason to want to do it, but today camera movement is so easy that everyone does it without thinking about it and it's time for us to start thinking about when it is time to keep the camera stationary

-Jon

[Michael Maier]

Originally Posted by Keith Wakeham

Maybe some C mount or CS mount lens for 1/2" could be adapted and someone make a primes series for the canon mount. I'd be interested in work on it but don't currently own an XL series camera.

Problem with C mount is that the back focal distance is much shorter than the XL series. CS is even shorter. So it makes it hard to use with a XL-H1.

[Keith Wakeham]

Maybe the lense elements can be moved to change the focal plane.

Probably just as easy to start from scratch and design a lense. Wish I had the gear to start experimenting.

I like the primes idea and even more if they could be built them realivitely cheaply. Would allow a nice option for people more into movie making and stuff vs situations where you need a zoom. For people who only make movies then being able to save the money on the zoom when they buy a body kit would definetly be a plus.

[Michael Maier]

Yeah, reworking the optics would be just easier to build them from scratch. C mounts don't work. I'm not sure they could be made cheaply though. If they were cheap, they would most likely no be any good for HD.

[Keith Wakeham]

Michael your right. If it they did exsist and were "cheap" then probably no good. I should use the term cost effective or really good Value.

Most lenses have so many elements though, that designing a prime lense would take a lot of work without some compromise. So wish I had access to a lense kit for experimenting. Sounds like fun.

[Jon Bickford]

don't forget they've got to be ultra fast

a few years back canon had an EF lens that was a 50mm F1.0, i think it sold for around 3 grand and they only made maybe 1500 of them total

I know a 1.0 is pushing it a whole lot but I imagine you could get 35mm depth of field with something that quick, i think a 1.2 is possible and effective enough to be worth it,

again, am i wrong that there would be almost as large of a market for H-1 primes as there would be for an H-1?

i just don't see ppl spending 9 grand to point and shoot their kids birthday for fun and the local tv and indie film guys (like me) would kill for some primes like that and it would really make the H-1 the most interesting "low price" camera, i could see thinking that the market wasn't there for a XL-1s prime kit but the H-1 is going after a completely different level of "prosumer" primes would bury the HVX.

if there isn't a market for primes explain the big hit that mini 35 made, and a set of native primes would be better in many instances, instead of the light loss of a relay lens, and adapter, and a lens, you could have a straight f1.2 to the chips by the time you get to a pl mount lens you've lost so much light that you're in need of more juice and that means a generator, and that means ppl setting up the generator, and that means paying off the neighbors to let you run a generator in front of their house, and running cable and leaving a deposit. as much as possible i like to light with the locations existing electrical but that generally limits you to 1.5k@120v and no matter how many different circuits are in the house once you start gelling down your 1ks you're hurting for light quite quickly with mini35.

[Tony Tibbetts]

Honestly, I would pay good money for a set of XL primes at 24mm,50mm and 85mm w/ 1.8 aperture.

[Keith Wakeham]

I've been doing a little looking around and their seems to be a lot of different lense designs over the last 100 or more years. The cooke triplet, the zeiss tessar, and more. These aren't brands (they are but not what i'm talking about) these are types of lense arrangements. I wish I could disassemble a prime lense to see whats in them. I'm thinking two lenses . A diverging one to get the backplane right and a converging one for gathering light. And of course a method to control the aperature.

I don't have enough optics understanding to figure out everything so I'm thinking out loud. I'm never going to be able to build one for a few months but I'm so interested now. Darn current projects that interfere with new project ideas.

[Keith Wakeham]

Tony, I'm assuming you mean prime equivalents for a 1/3" sensor that would give the same FOV as the 24, 50, 85mm on a 35mm film camera. Correct?

[Nate Weaver]

Originally Posted by Keith Wakeham

I wish I could disassemble a prime lense to see whats in them...I don't have enough optics understanding to figure out everything so I'm thinking out loud.

Over the years a lot of the still photography lens makers have included cutaway artists renderings of the construction of their lenses. Even in a single focal length lens, there's a lot more than 2 elements. More like 7 or 8:

http://www.mir.com.my/rb/photography...ernalillus.jpg

[Nick Hiltgen]

I think there is a possibility that you're right and that people would buy primes, but I disagree with the reasoning and the extent. I mean come on, the guy shooting his kids birthday party doesn't care about prime lenses, if anything he wants a zoom. Can you imagine his dismay at losing all of that "great" footage because he were too busy changing lenses? A TV station isn't going to want primes because if it's live, they're going to need to be able to change the length of the lens quickly, and you don't get that with primes, at least not compared to zooms.

So the only place that leaves a market for primes is the indie movie market. Let's talk about HD glass now, a set of zeiss digiprimes (for b4 mount cameras) is roughly 20k a piece, fuji and canon both have some as well and they come in slightly cheaper. Now I realize this is a "prosumer" format camera but it has a smaller imager so the glass is going to need to be at least pretty close to the same quality. but let's say they can make it for half price, heck let's say they can make them for a quarter of the price, is everyone going to go out there and spend $3500-5000 on a single prime lens if there were only 3 that you wanted, say 24mm, 35mm and 50mm you're still looking at the cost of the camera. For what? 3 prime lenses that still don't give you 35mm depth of field. Which I believe is the reason that the mini 35 took off technically you can put zoom lenses on that as well so it's not a prime only thing it's a 35mm plane thing.

I think to be honest unless they can get REALLY good quality optics for 1/10th the price of "professional" HD primes, there's really not a market for it. But hey that's just my opinion. Personally I would love to get a lensless xl-h1 and a mini 35 with some superspeeds but that doesn't meed they should sell that as a package too...though they should ;)

[Michael Maier]

It would help if Canon didn't insist on their own 1/3" mount, and used the standard 1/3" bayonet mount (same the HD100 uses). Then as the market would be larger, the possibilities for somebody releasing a prime set for this mount would be bigger. Much like B4 is the standard for 2/3".

[Nick Hiltgen]

Good point michael, I suppose if there was some sort of standard mount then a company like century may have motivation to create a set of primes knowing that the potential market would be larger.

[Keith Wakeham]

Haven't seen the two mounts side by side but wonder about the possibility of building an adapter. Have a feeling it would put the focus plane out a litte. Thoughts.

I do know their are more elements that the 2 I described in most commercial lenses but since I'm only talking theory and at the simpliest idea stage now that I'm starting with the simple problems and then will think about the others later. I'm thinking that for every lense added their is more light loss. Some of these lenses are doublets for reducing chromatic abberation and other distortion.