Fast working c-Mount Zoom?

G

GPSchnyder

New member
Hi,
I've searched the last two days, mostly here, but also in other forums, but didn't find the answers I searched. I want to use c-Mount lenses on my GH1 purely for movie mode. And I don't mind the quality/sharpness of an Image that much also. Lenses don't have to be razor sharp to make me think they produce great images.

What's more important is the ability to have a fast lens (for that dof) and no black peephole borders. I don't mind a little vignetting, but not pure black.

What I need is a zoom that goes from wide (like 12,5 or so) to a slight tele (100) at around f1.8 or less.

But here is lays my problem. I know that spreadsheet on google, but they all (besides one I think) are primes. And I don't want to order a Zoom just for testing as most of the price will be the shipping cost from the US to Germany.

So please, does someone know a c-mount zoom that works on the GH1 with the upper specifications? Even if not all is matched I'd probably like to take a look.

Tanks in advance,
George
 
The trouble with c-mount zooms on the GH1 is that they all seem to vignette, and vignette more than primes do even at equivalent focal lengths - and there are no c-mount lenses as far as I know, that down to 12.5mm will cover anywhere near the full GH1 sensor.

The closest anyone is getting to what you're after, is buying a c-mount zoom, and converting the mount so that you can use a 35mm teleconverter on it (some threads on this board about a guy who used a nikon teleconverter on a zoom), you need that in order to get a big enough image circle...but you've lost your ultra-wide and you've lost your fast aperture.

I think the only way to get what you are after is to rent a PL mount 35mm film zoom lens, they do exist in specs near what you are looking for.

Now, if someone made an HDSLR with a 16mm film sized sensor so we could use these c-mount zooms at their full potential, we'd be in heaven...but then of course there would be other drawbacks to that smaller sensor.
 
GPSchnyder said:
What I need is a zoom that goes from wide (like 12,5 or so) to a slight tele (100) at around f1.8 or less.
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So all you want is an f1.8, 12-100mm zoom ?
I think everyone in the world wants a lens like that. You absolutely won't find anything like that so you'll have to adjust your expectations. Sounds like you need 2 separate lenses.
 
iHartVideo said:
So all you want is an f1.8, 12-100mm zoom ?
I think everyone in the world wants a lens like that. You absolutely won't find anything like that so you'll have to adjust your expectations. Sounds like you need 2 separate lenses.
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Thanks for your Answer. I know that it's near to impossible, that's why I said I can live with things that ar not like that. I love the linked one on E-Bay, thanks majikfraug. But it unfortunately ships only to the US and I don't know how it will look vignetting vise. Is there a way to get to know the Vignetting without buying the Lens up front?

George
 
iHartVideo said:
Lol... well, what do I know. I am too stuck in the Stills world where a 1.8 12-100 (or even 12-75) is unheard of.
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Would be 24-150 in 35mm eq. so that is not that unheard of, or? C-Mount Lenses are designed for 16mm Cams, or as this TV-Lens, for cams with a Sensor rondabout as big as 16mm.

The Problem is that some Lenses are designed for 1/3" or 2/3" Sensors and will not cover the 4/3 Sensor fully. Some are designed for 1" Sensors, and they will cover the Sensor fully or just with vignetting. At least that's what I've learned in the last days surfing the Net. So please, if there is someone who knows it better feel free to write down what I've gotten wrong. Everyone will learn from it.

George
 
iHartVideo said:
Lol... well, what do I know. I am too stuck in the Stills world where a 1.8 12-100 (or even 12-75) is unheard of.
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Yeah, the cine-lens world is completely different (but also way, way, way more expensive). Check out: http://www.zeiss.com/cine

You'll be blown away by what they offer if you come from a still photography background like me...one of their digizooms is 17-112mm at f1.9

Keep in mind that these lenses are mostly designed to cover Super35, which is smaller than a 35mm still camera negative, which may be why its easier for them to make some of these incredible lenses whereas the image circle would just have to be too large in order to get it to work on a 35mm still camera body.

It seems that if you are going the c-mount route, your only hope is finding a lens a designed for 1" tube video cameras, but it's really hard to find information on these lenses nowadays. I have a Canon 18-108 f/1.6 that I *think* is meant for a 1" tube but I still haven't tried it out on the GH1. Maybe it's time I get myself a c-mount adapter.
 
thisisapocalypse said:
I have a Canon 18-108 f/1.6 that I *think* is meant for a 1" tube but I still haven't tried it out on the GH1. Maybe it's time I get myself a c-mount adapter.
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Willing to sell it if it works? With the matching Adapter. Will pay a good price if I know that it'l work...

George
 
iHartVideo said:
I've never seen a 1.8 zoom of any sort.
The fastest that are typically made are 2.8, and they dont go from that wide to that long.
They are usually 17-55 or 70-200 f2.8
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You're right when it comes to still photography but the world of cine/tv lenses is quite different (and much more expensive) I had no idea that lenses existed like the others are talking about until very recently.
 
GPSchnyder said:
Willing to sell it if it works? With the matching Adapter. Will pay a good price if I know that it'l work...

George
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I will be testing it out soon - I will let you know how it goes. I've got a couple more c-mount zooms too...time to put them through their paces.
 
I have a Canon 17-105mm f2 c-mount zoom lens which is quite compact with a 58mm filter diameter. However, it does vignette at all focal lengths on the GH1, and cropping the usable image out of a still frame leaves you with a 6 megapixel image. I'm considering trying it out with a 2:1 anamorphic lens adapter, which should stretch the vignette outside the 2.35:1 crop of a cinemascope frame. This is the only practical way I can see using it as an HD video lens.
 
You can get lenses made for 1" video cameras in C-mount that will probably cover a GH-1. I have a couple of old Canon TV zooms F1.8 25-100mm that I think will cover 1". Nothing wider though.
There is the Angenieux 10x18j1 f1.8 18-180 that is made for 1-1/4" plumbicon broadcast cameras, coverage would not be a problem and you can buy them cheap. But they are 6" in diameter at the front element, about 16" long and weigh 20lbs. It typically carries a threaded mount, but it is not a C-mount. You would need someone to make an adapter for you and it would need to have adjustable back focus.
 
Were there other lenses made for the 1-1/4" plumbicons as well ? Just wondering if there is a list somewhere ?
Razz16mm said:
You can get lenses made for 1" video cameras in C-mount that will probably cover a GH-1. I have a couple of old Canon TV zooms F1.8 25-100mm that I think will cover 1". Nothing wider though.
There is the Angenieux 10x18j1 f1.8 18-180 that is made for 1-1/4" plumbicon broadcast cameras, coverage would not be a problem and you can buy them cheap. But they are 6" in diameter at the front element, about 16" long and weigh 20lbs. It typically carries a threaded mount, but it is not a C-mount. You would need someone to make an adapter for you and it would need to have adjustable back focus.
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zcream said:
Were there other lenses made for the 1-1/4" plumbicons as well ? Just wondering if there is a list somewhere ?
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I don't know. Probably Canon made similar lenses. The Angie is the only model like this I have ever seen show up on Ebay There was some guy a while back that sold off quite a few of them.
The one I have has cloudy coatings on the front element from open warehouse storage, so is optically not so good. The front element is flat on its exposed side, so I may at some point just polish the old coatings off to play with it.

The two f1.8 25-100mm Canons I have are definitely for a 1" or larger imager and should cover the GH1 with no vignetting. I need to get a retaining collar made for the C-mount barrel attachment for one, it did not come with the lens. No real wide angle coverage with this lens though. These were studio camera lenses.
Both are clean and in good working condition with smooth mechanics, though they could use lubrication. One is geared, but I don't know if it would match up to current FF standards.
If any one is interested I would sell them. Last ones I saw on Ebay were in the $650 asking range. I would take much less. Have too many lenses on hand, but most are for 16mm and would vignette on a GH1.
 
iHartVideo said:
So all you want is an f1.8, 12-100mm zoom ?
I think everyone in the world wants a lens like that. You absolutely won't find anything like that so you'll have to adjust your expectations.
Click to expand...

Well, many many moons ago my two favorite lenses for shooting with 16 mm Arri ST cameras was a Angenieux 12-120 f/2.2 and a Zeiss Vario Sonnar 12.5 - 75 f/2.0 but I doubt any of those would cover the 4/3 sensor below 35mm focal length or even then.
 
Martti Ekstrand said:
Well, many many moons ago my two favorite lenses for shooting with 16 mm Arri ST cameras was a Angenieux 12-120 f/2.2 and a Zeiss Vario Sonnar 12.5 - 75 f/2.0 but I doubt any of those would cover the 4/3 sensor below 35mm focal length or even then.
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I have two Angie 12-120's. An early model A-type F2.8/T3.1 with the pellicle optical viewfinder on my old Auricon 16mm camera and one of the last produced versions, a T2.1/f1.9 HEC version with the advanced high contrast coatings.
It will be interesting to compare these two on a Scarlet so people can see the best and the worst a 12-120 can be. Even the old ones are fine lenses if they are clean and well maintained. There are I am sure a lot of worn out junkers out there too. These things were made by the thousands from the 50's to the late 80's. They along with original AC powered and modified battery powered versions of the Auricon mag stripe sound on film cameras were the staple of TV news bureaus for nearly 25 years after WWII.
 
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