Jump to content

Still Lens vs Cine Lens


Michael Ryan

Recommended Posts

Hello All,

 

About a month ago I started using Kodak 35mm 400UC professional film in my still camera. My still camera is a 35mm Canon TX which is an old metal body camera that is built like a tank and has served me well for many years. I mainly use a 50mm Canon lens with this camera.

 

When I got my film back from the lab I was AMAZED! I had shot several portrait type photos of people standing next to window (inside). I got a real "northern light" effect. I shot at 2.8 1/60th of a second. The shots came out very, very sharp. The colors were very good. This was a low light situation as there was no direct sunlight (it was around 4 in the afternoon). There was no artificial light used for these photos.

 

Here is my question or observation: I have shot with Super 8 and some 16mm in a similar situation and there was just not enough light to give a very good image.

 

The cine lenese are much smaller. The still camera lens is much larger. Is it that the larger still camera lens is capturing more light (even at the same f stop and shutter speed)? The cine lenses have less glass so there is less light getting to the film?

 

Mike

Link to comment
Share on other sites

  • Premium Member

The movie film was probably a different speed. Or, if not a different speed, it is simply a smaller negative and won't look the same at a given speed.

 

The issue isn't anythign with the size of the lens. An f-stop takes into account the size of the glass elements, that is why an f2 on this lens will expose the same as an f2 on any other lens.

 

Another issue could be exactly what lenses you're comparing. A brand new, high end SLR lens is almost surely going to give a better image than a 40 year-old 16mm zoom, for example. On the other end of the spectrum, if you compare new high end cine primes to new high end still primes, the cine lenses will win every time. That's why they cost ten or twenty times as much.

Link to comment
Share on other sites

  • Premium Member
The 35mm stills neg is much bigger than 16mm and Super8mm, so obviously you'd get more sharpness with less grain.

 

The larger the negative, the lower the MTF of the lens can be and still give you a sharper image, because it's being enlarged less ultimately.

Link to comment
Share on other sites

  • Premium Member
The larger the negative, the lower the MTF of the lens can be and still give you a sharper image, because it's being enlarged less ultimately.

 

I'm curious if the reverse of that can be true as well, the larger the diameter of the lens, the better the result, which is what Michael has already asked. When I purchased an aftermarket fujinon lens for my 1/2 inch chip E.N.G. camera I picked up an immediate benefit in low light situations. It turns out the lens was actually made for a 2/3 inch chip camera and was modified to fit on a 1/2 chip camera.

Link to comment
Share on other sites

I have a few follow up questions.

 

For David: What does MTF mean?

 

For Alessandro: I think you understood my question. That was really my point.

 

I didn't quite explain it very well in my first post, so let me give it another try. I understand that the 35mm negative is larger than the Super-8 and the 16mm. What I'm trying to say is that under low light conditions (Northern light from a window with no artificial light), the 35mm negative and the 50mm Canon still lens produced very excellent results. I'm not talking so much about the grain or the colors, but that the light that the lens captured produced an image that captured detail and was not dark (and in fact the color and sharpness were very good but that's not my main point).

 

Now, why is it that when I have used my Super-8 camera with a similar film, same shutter speed 1/60th and same F stop 2.8 the image was so dark that you could barely see anything. Really it was not viewable.

 

Is it because the 35mm lens is much larger and can capture more light? Or is it a combination of a bigger lens and a bigger negative? Or I'm I missing something?

 

I remember seeing a picture of the low light lens (F.95) that Kubrick used in BARRY LYNDON and it looked very large, so I'm thinking that the diameter of the lens is important? I have seen those adapters on eBay for Bolex 16mm cameras where you can mount Canon and Nikon still lens on the Bolex. Would this set up capture what my still Canon could capture.

 

I guess my point is I was very impressed with the image my 35mm Canon still camera could capture under very low light conditions. Why can't my Super-8 do the same thing? Would I have to use my 16mm (I have a Canon Scoopic and a Kodak K100) to get the same results as my still camera? What 16mm film could I use to get the same results?

 

 

 

Mike

Link to comment
Share on other sites

  • Premium Member

The diameter of the lens in relationship to the film does not have an effect on the sharpness of a lens. You could use a lens with coverage for an 8x10 inch camera and it would perform the same regardless of having a sheet of 8x10 behind it or a frame of super 8 behind it.

 

North skylight shouldn't be that "low light", really. It should comfortably expose 400 speed film. If your super 8 camera couldn't get an image under those conditions, there was an exposure problem.

Link to comment
Share on other sites

THe diameter of the lens is not the sole determinant of the brightness of the image. The focal length, which governs how big the image is, also plays a factor. The ratio of the two numbers gives the f/stop, which is the actual number that tells you how bright the image is.

 

What that really means is that the lens on your 35mm camera has to be larger to gather more light, as the light has to produce a much larger image on the film than for the super-8 camera. Bigger lens, more light, larger image, same image brightness (and therefore exposure).

 

If your super-8 film was too dark to see, it was underexposed.

 

Not clear if you shot reversal or negative in your super-8 camera - but if it was reversal, then it would have much less latitude (and therefore tolerance to underexposure) than the 35mm stills negative stock.

 

MTF is Modulation Transfer Function. It's basically a scientific measure of film's sharpness and resolution, in relation to different contrast ratios.

See Wikipedia

or this visual explanation

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...