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Bolex H16S


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#1 Rolando Fernandez

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Posted 07 December 2008 - 08:11 PM

Hi, I will test some film to see how it looks.

Any one here has try this setup?

http://www.prtc.net/...ronic/bolex.htm
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#2 Ira Ratner

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Posted 10 December 2008 - 05:48 AM

I didn't know they made something like that.

Does that mean I can get an MD to M42 adapter on top of that, and use all of M42 lenses?

WHich means I now have more reason than ever to buy myself a Bolex?
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#3 Ian Cooper

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Posted 10 December 2008 - 07:23 AM

I didn't know they made something like that.

Does that mean I can get an MD to M42 adapter on top of that, and use all of M42 lenses?

WHich means I now have more reason than ever to buy myself a Bolex?



Bolex uses a 'C mount' thread, not M42.

C mount has a flange focal distance of 17.526mm, so an awful lot of other types of lens can be put on adapters to work with it.

Minolta MD/MC has a FFD of 43.5mm, whilst M42 has a FFD of 45.5mm.

On this basis, fitting an MD/MC mount lens on an M42 camera is going to be exceedingly difficult, if not impossible! I doubt you'll find an adapter to go that way around, you might find one to put an M42 lens on a Minolta MD/MC mount camera though, as that should work!
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#4 Patrick Neary

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Posted 10 December 2008 - 10:20 AM

I didn't know they made something like that.

Does that mean I can get an MD to M42 adapter on top of that, and use all of M42 lenses?

WHich means I now have more reason than ever to buy myself a Bolex?


Hi- Just get a M42 to c-mount adapter, ebay is rotten with them, B&H and a lot of other camera shops have them.

And before someone jumps in and explains that a 50mm still-camera lens magically becomes a 100mm lens on a 16mm camera, no, it doesn't.
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#5 Ira Ratner

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Posted 10 December 2008 - 07:38 PM

Patrick, I had no idea about this. I thought that the ONLY advantage of my M42 K3 was the capacity to take those lenses. I didn't know a C-mount could.

Are you saying M42 camera to C lens? If so, that's nothing I want or need. It's C camera to M42 lens, like posted here.

And what do you mean that a 50 doesn't become a 100? I have a s***load of lenses I recently bought, haven't shot yet, but this was the premise I've been working off of.

Is there like a different formula for the conversion for each focal length?

I mean, I have just about every range covered and I'll know what's what when I screw the things on, but I'd like to know the theory and actual math.

Edited by Ira Ratner, 10 December 2008 - 07:40 PM.

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#6 Patrick Neary

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Posted 10 December 2008 - 08:05 PM

Hi-

It's a M42 (or pentax screw) lens to c-mount camera adapter, like this:

http://www.bhphotovi...for_Pentax.html

There's no conversion for stills lenses. If you want a slight telephoto or portrait lens, and sitting on the table in front of you is a pentax 50mm lens on an adapter, and an old Yvar or Wollensak 50mm lens that came with your bolex, either lens will give you essentially the same field of view. They're both 50mm, no math, end of story, period.

hope that clears it up! :)
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#7 Ian Cooper

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Posted 11 December 2008 - 04:28 AM

...And what do you mean that a 50 doesn't become a 100? I have a s***load of lenses I recently bought, haven't shot yet, but this was the premise I've been working off of.

Is there like a different formula for the conversion for each focal length?

I mean, I have just about every range covered and I'll know what's what when I screw the things on, but I'd like to know the theory and actual math.



A 50mm focal length lens remains a 50mm focal length lens... but what changes is the "angle of view" a certain focal length will give depending on the size of the imaging sensor.

On a 35mm camera a 50mm lens might give what is considered a "normal" angle of view, to achieve the same angle of view on a 16mm camera will require a different focal length, ie. 25mm.

A lens of a given focal length will project a certain sized image and that won't change. If you put a 35mm sized sensor (ie. bit of film) behind the lens then it will capture more of that image than if you put a smaller 16mm sized bit of film behind the lens.

This is the reason why a super-8 camera will be supplied with a 12mm lens as its "standard" lens, a 16mm camera will have a 25mm lens as "standard" and a 35mm camera will possibly use "50mm". The focal length keeps doubling, but the angle of view will remain the same across all three. This is why digital stills cameras tend to have lenses with a focal length around 7mm, to achieve the same angle of view as a 35mm stills camera achieved with 50mm.
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#8 Ira Ratner

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Posted 11 December 2008 - 08:52 AM

Thanks for reminding me about this. I knew that, but from a mental point of view for a lot of us who did 35mm still work, we can't resist thinking in that doubling method, though tehnically wrong.
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#9 Ira Ratner

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Posted 11 December 2008 - 08:55 AM

And Patrick, I think I see a Bolex in my future.
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#10 Patrick Neary

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Posted 11 December 2008 - 10:36 AM

Thanks for reminding me about this. I knew that, but from a mental point of view for a lot of us who did 35mm still work, we can't resist thinking in that doubling method, though tehnically wrong.


doubling/halving is close enough when you're talking about matching the angles of view between the two formats, but once you start shooting 16mm, you'll just think in terms of 16mm (as far as the effect of focal lengths go) instead of 35mm.

In stills shooting I've never heard any concern or confusion about the different fields of view between 35mm, medium format and large format, I mean if you're shooting 4x5 architecture and you need a wide-ish lens, you throw on a 90mm, you don't first think, "what's the 35mm equivalent of a XXmm lens?" You just "see" in the focal lengths as they relate to the format you're working with.

The whole conversion thing is just an unnecessary (and unnecessarily confusing) step for most people.

Ian's post above should be pinned somewhere on this site, it's one of the clearest explanations.

And get a bolex!!! I haven't had one for years, but they are great machines!
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Gamma Ray Digital Inc

Visual Products

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Technodolly

rebotnix Technologies

Broadcast Solutions Inc

Abel Cine

Tai Audio

Ritter Battery

CineLab

CineTape

Wooden Camera

Glidecam

Rig Wheels Passport

Aerial Filmworks

Willys Widgets

Media Blackout - Custom Cables and AKS

Opal

FJS International, LLC

The Slider

Metropolis Post