OT - lens focal length comparison charts

vicmilt wrote on 5/8/2006, 11:16 AM
I stumbled across this wonderful comparison interactive lens comparison chart from Panavision.

It lets you know the equivalent lenses for just about every camera system out there.

So to see what a 35mm lens in 2/3" or DV or 16mm or a bunch of others is, you use this chart.

For instance a "normal" 50mm lens in 35mm MOVIE size equivalent is only 12mm in 1/3" or 16mm in 1/2" or 22mm in 2/3". This is a major reason why you can't get that 35mm soft focus - limited depth of field - FILM LOOK in video.

Theoretically that new proposed "Red" camera by Oakley will have a CMOS imager as large as the original 35mm Film size.

That'll be the day that video crushes film forever.

http://www.panavision.co.nz/main/kbase/reference/tblelenseqvform.asp

v

Comments

farss wrote on 5/8/2006, 3:09 PM
Victor I think your assumptions are too restrictive.
A 16mm lens on a 2/3" imager CAN give the same DOF as 35mm, the 16mm lenses typically can open up one or two stops more than 35mm lenses can.
I'd also suggest following your line of reasoning then 35mm is quite inadequate compared to 65mm, where does it end, basically it's a nonsense argument, we learn to use the tools we have, better tools don't make for better story telling.
I have the exact opposite point of view actually, I detest shallow DOF, it's a technical abberation that destroys the story. My eyes don't have shallow DOF so when I'm forced to watch images with burnt in shallow DOF I immediately know it's a fudge, that someone is trying to manipulate my brain.
The challenge for Cinema shouldn't be to let the viewer watch another reality, rather it should be to place them in another reality, the experience should be totally immersive.
The first step is going to be getting rid of those EXIT signs in cinemas.
Bob.
Coursedesign wrote on 5/8/2006, 4:13 PM
My eyes don't have shallow DOF...

True, but your brain does, and the brain is what really sees (perceives). You see only a 1.6 deg. cone in full focus, and the seemingly larger in-focus area is just created by your brain summing several impressions.

I don't see how the use of selective focus is different storytelling-wise from say hand gestures that say "lookee here now!"

Rack focus and shallow DOF can be used to support the storytelling, or to mess it up if it seems artificial as you indicated. It's all in a DP's day...
farss wrote on 5/8/2006, 5:15 PM
All true and I agree whole heartedly re story telling. However there's also The Greatest Story Never Told - Reality.
No 'story', no DoP needed. The audience isn't to watch a 'story' they're there to be IN another world, in The Matrix if you like.
The audio side needs serious attention too, 11.2 seems good enough for the task.
vicmilt wrote on 5/8/2006, 6:04 PM
Actually, there's a little bit more to it all...

first, - no doubt -, selective focus is a technique that I personally used a lot - it's a part of my palette that I dearly love and totally miss in DV. Couple that near infinite depth of field with the shortness of the lenses and it just "ain't the same" - especially for those seeking the eternal grail of "the film look". (not me - I just like those lenses).

It's funny in a way. When I was a young film maker, everyone was striving for the "35mm" look - being limited to 16mm for reasons of budget. Same crap, new day.

Now, I'm always yammering on about CONCEPT and I totally agree - a good story can be told with ANY media, if you're enough of a genius.

Look at what Ingre can do with a piece of dirty charcoal.

Anyhow, I let my personal emotions get in the way of objectivity and you are right again. Beautiful, magnificent movies can be made with the correct use of ANY lens, in the right hands. One of my favorite photographers did these extraordinary photos with a pinhole camera - which allowed him unbelievable depth of field and extremely wide angles - and I loved it. ( I think it was nudes by Bill Brandt, but I'm pretty bad on names - maybe someone here can help me out).

Nevertheless I look to the day that I can shoot with 35mm (type) lenses, not only for the limited depth of field that they provide, but also for the compression of space that they allow - but that's me.

I'd love to see what you do with your point of view - I'll bet it's great.

best,
v


Coursedesign wrote on 5/8/2006, 7:39 PM
I think it was nudes by Bill Brandt

As Jean Luc Godard said, "Making a film is easy, all you need is a girl and a gun." :O)

Citizen Kane used a lot of wide shots to get maximum depth of field, that worked too for that particular film.

Still, the best storytelling I ever saw was one guy from the UK telling a seemingly very simple story about a bottle of Amontillado (Sherry).

He kept a live audience of about 200 people absolutely spellbound for more than one hour, using just words and intonation and a few simple hand gestures.

Nobody went to the bathroom, nobody sneezed, nobody sighed, nobody coughed, nobody blinked unnecessarily. There was only a communal breathtaking focus on his story.

Absolutely unforgettable, the non plus ultra of storytelling.

rmack350 wrote on 5/9/2006, 10:00 AM
Bob,

In the springtime I do a lot of wildflower photography. Being able to control and compress my depth of field is very important to making the flower, stem, leaves, stand out from the mass of other things in the background.

Reality? Im looking at a monitor now and the art on the wall 6' behind it is out of focus. I look at the art and my monitor is out of focus. That's reality too.

We're looking at that reality in two different ways. You look at the real world and say "Everything I look at is in focus". I'm saying "Yeah, and everything I'm not looking at is out of focus". Shallow depth of field simulates the later, or you could say that it simulates mental focus or even concentration.

So, that brings me to my imaginary 3D picture idea, where things you are focused on in the picture come into focus while other parts of it go out of focus. Just like reality.

I tried it in college with an animation that alternated images every other frame. Yes, you could chose to focus on one or the other image (brown haired guy with dark eyes and mustache alternating with dark haired girl with blue eyes). You could see the blue eyed person or the person with the mustache --mostly. You could also get a rocking headache. It wasn't an excercise in depth of field but that and high frame rate would be the next step to try. It'd probably induce migraines.

Rob Mack
farss wrote on 5/9/2006, 12:51 PM
Interesting idea, of course real 3D is yet another device that brings more reality to the screen. There's a small 3D cinema in Sydney used to take you on a journey through our solar system, simply amazing stuff done with real time generated images, I saw people in the audience trying to hold the moon they though was inches in front of them.

But to a less esoteric problem. Anyone seen March Of The Penguins, on the big screen that is?

Image wise it's a disaster, just my opinion here and for sure I have the upmost respect for those who shot it however visual quality is what makes or breaks this. Probably 16mm and widescreen was a bad choice from the start but all the underwater footage looks like it was SD video and pretty bad video at that.
Maybe the real issue was just not enough money, if they can get an Imax camera to the top of Everest than a 35mm camera with suitable lenses at the South Pole should be relatively simple.

Bob.
Jay Gladwell wrote on 5/9/2006, 1:43 PM

Citizen Kane used a lot of wide shots to get maximum depth of field, that worked too for that particular film.

In reality it took far more than just "wide shots" to get the depth of field in that film. Back in the day, which Victor can attest to, and any other cinematographer from days gone by, the film stocks were incredibly slow in the 30s and 40s. It sticks in mind that I read that the film stock for CK had an ASA of 32 or 50--very slow. It takes a great deal of light (especially on interiors) to get a decent exposure with a stock that slow. It took even more light to get any depth of field.

What many don't realize is that most of the "famous" deep focus shots in CK are actually mattes while others were composed in an optical printer. In any case, it worked!

This whole thing is quite ironic, really. There was a time when cinematographers busted their butts to get a deep depth of field in their films. Now that we can achieve that so easily, everyone wants shallow depth of film.

You just can't please some people.

[CORRECTION]

Citizen Kane was shot on Eastman Plus-X negative stock (5231). It's ASA under tungsten was 64, while in daylight it was rated at 80. That means that on a bright, sunny day your lens f/stop would have been about f8.


farss wrote on 5/9/2006, 1:59 PM
The early 3 strip Technicolor was so slow even daylight needed help. I read of one studio shot when the director told the DoP he needed both talent in focus they nearly had a cardiac arrest, back then the only way to make LOTs of light was carbon arc lights and the fumes were really bad, studios had to be vented with huge fans ever 30 minutes or so.

Bob.
Serena wrote on 5/9/2006, 5:22 PM
When I started cinematography (as a 12 yo) Kodachrome was 12ASA. Much later Kodachrome II made a huge leap in speed to 25ASA. As Farss has mentioned, the major characteristic looked for in lights was output.