Ground Glass

[Nate Yolles]

As I mentioned earlier, I've purchased a 35mm camera. Now I'm designing my ground glass for camera and would like some opinions.

 

The glass that is in the camera now is a beautiful piece marked with Academy, TV safe and 1.85, as seen below.

 

I do, however, want to be able to compose for 2.39 as well. Does this seem to cluttered?

 

It was suggested that I just put the edges of 2.39 in. But that might still be too difficult to frame unless someone is riding the frame edge.

 

I could go with a common topline.

 

I think this last one is the best for keeping every ratio while keeping the clutter away. Would it ever be a problem though, if I shot in 2.39 and the frame isn't centered on the negative. When I goto video, in telecine they can recenter the frame - no problem. If I am correct, shooting for print won't cause a problem either. There's an optical step to goto anamorphic anways, so they should be able to recenter while doing that step. Am I missing anything? Did I overlook anything? Do you think that this would be the best ground glass design?

[David Mullen ASC]

Sure, sounds fine, other than the fact that cropping the Academy area to 2.39 is a waste if you can compose 2.39 across Full Aperture (Super-35) instead.

 

The main problem with common topline is that you are not in the optical center of the lens, so while zooming, you will have to also be tilting the camera to get something centered.

[Nate Yolles]

Sure, sounds fine, other than the fact that cropping the Academy area to 2.39 is a waste if you can compose 2.39 across Full Aperture (Super-35) instead.

 

I understand the s35 and the waste issue. I also understand that this MOS camera won't be the A camera on too many features and probably about 99% to 100% of the footage off of the this camera would be destined for telecine rather than print.

 

The main problem with common topline is that you are not in the optical center of the lens, so while zooming, you will have to also be tilting the camera to get something centered.

 

That's an excellent point. So now the question would be which is the lesser of the two evils: more clutter on the ground glass or tilting while zooming?

[David Mullen ASC]

Well, a bigger problem is if this is a B-camera, how will the A-camera be set-up? You don't want one camera doing common top 2.39 within the Academy aperture and another doing center extraction 2.39 within the Super-35 aperture. If the "2.39 within Academy" is just for your own projects, then whether you choose common top or center just depends on which you prefer to deal with and how often you plan on zooming.

[Nate Yolles]

2.39 would mostly be for my own projects and I'm not exuberant about doing a great deal of zooming, so it does in fact come down to personal preference. I've never framed with a common topline before so I'm simply asking for other's thoughts on the subject. Whether you think tilting with zoom is worth clearing the ground glass of extra lines? Or if the extra markings even bother you, would you find it distracting and hard to choose the correct framing when all the action is happening?

[John Sprung]

Why limit yourself to just one "Swiss army" ground glass? Use the one that's in there for now, and as funds become available and projects require them, get more. Ideally, you should only be looking at the format that you need for the movie you're working on.

 

 

 

-- J.S.

[Adam Frisch FSF]

Yeah. Just like Fred Elmes, I prefer my ground glasses to have as little on them as possible (all other comparisons with Elmes greatly appreciated :P ). Don't you think it would be to cluttered for everyday use?

[Nate Yolles]

Exactly, that's the point. I don't want excess distractions running through my finder. Ideally I would have a different glass for 1.85 and 2.39 pseudo-scope like you mentioned. Here's the deal; it's my understanding that the ground glass is not easily accessible in this camera (Cameflex CM3). Please let me know if I have been misinformed.

[J. Lamar King IMPOSTOR]

Personally I don't mind those lines with the common center. It gives me something that feels more precise, like an ever finer site, if I were shooting TV or 1.85. Sounds like you already feel it's too cluttered for your tastes.

[Mitch Gross]

While I admit that I do not really know, I find it hard to imagine that the CM3 has a difficult to interchange groundglass. This is the camera designed to shoot both 35 & 16! Surely they made interchangeable gg just for this (and stop calling me Shirley).

 

Beyond this, it is easy enough to work with common topline, or at least an upper-favored topline. That's what Jim Cameron did for a couple of films.

[Patrick Neary]

Well, a bigger problem is if this is a B-camera, how will the A-camera be set-up?  You don't want one camera doing common top 2.39 within the Academy aperture and another doing center extraction 2.39 within the Super-35 aperture.  If the "2.39 within Academy" is just for your own projects, then whether you choose common top or center just depends on which you prefer to deal with and how often you plan on zooming.

<{POST_SNAPBACK}>

 

 

Maybe I'm too sheltered- I've never heard of anyone pulling 2.39 out of academy- Has anyone ever really done this? It seems like combining the worst of both s-35 (the optical step, if that's even an option) and academy (smaller image area).

[David Mullen ASC]

Historically, the forerunner to Super-35 was SuperScope, which involved extracting a 2:1 image from inside Academy and blowing this up to CinemaScope with side mattes to preserve the 2:1 image. This was improved two years later with SuperScope-235, which involved extracting a 2.35: 1 image from inside Full Aperture. But just when that was developed (not sure if any features got made in SuperScope-235, just SuperScope), the whole idea died because cropping to 1.85 for projection seemed cheaper. Remember that SuperScope was a poorman's widescreen system.

[Nate Yolles]

Like you said David, this is a "poor mans widescreen." I'm not converting the camera to super35 and for my own projects I'd like to be able to shoot in the 2.39 aspect ratio. It is what it is. That being said I'd still like some of my peer's opinions on the ground glass.

[Mitch Gross]

I believe that the 2-perf format that is being promoted in Australia is within Academy so as to utilize certain cameras and lenses.

[David Mullen ASC]

It's mainly because 35mm 2-perf Full Aperture is 2.66 : 1, so there's no need to use anything wider than Academy.

[GWilliamPatrickB]

Well, a bigger problem is if this is a B-camera, how will the A-camera be set-up?  You don't want one camera doing common top 2.39 within the Academy aperture and another doing center extraction 2.39 within the Super-35 aperture.  If the "2.39 within Academy" is just for your own projects, then whether you choose common top or center just depends on which you prefer to deal with and how often you plan on zooming.

<{POST_SNAPBACK}>

 

The same way it would if you wound up shooting 1, 3 perf and 1, 4 perf as in episodics. Shoot a framing leader and there is no worriy about the A and B camera setup difference.

 

GWPB

[David Mullen ASC]

You're assuming a digital post. What about an optical printer blow-up to scope? You don't want to mix 3 and 4-perf negative plus have to worry about two different framing styles for 2.39 extraction, especially when A and B camera footage were intercut back and forth in the same scene.

[GWilliamPatrickB]

You're assuming a digital post. What about an optical printer blow-up to scope?  You don't want to mix 3 and 4-perf negative plus have to worry about two different framing styles for 2.39 extraction, especially when A and B camera footage were intercut back and forth in the same scene.

<{POST_SNAPBACK}>

 

Yes, quite right David. However, I am also making the assumption anyone playing around with 35mm has gone and hired a real DP that would not make such a mistake.

 

GWPB

[Guest Daniel J. Ashley-Smith]

I take it a groundglass is something that slots into the viewfinder, and gives a borderline to help frame a specific ratio?

[Phil Rhodes]

Hi,

 

Yes, essentially. Any optical viewfinder needs a screen to project onto - the groundglass (it's a piece of glass with a ground surface, so the viewfinder can project onto it from behind) has to be there, it's what you're looking at. It has lines etched into it which show you where the framelines are. Clearly this is a different situation with a video camera where you're looking at a tiny CRT or LCD monitor, and the frame lines are electronically superimposed on the image.

 

The insidious thing with film cameras is that, obviously, what ends up on the film is not necessarily exactly the same as what you see in the viewfinder. It's usual to shoot a chart with black tapes on it, lined up looking through the viewfinder, so that you have a reference exposed on film as to where the lines appear to be through the finder.

 

Phil

[Guest Daniel J. Ashley-Smith]

It's usual to shoot a chart with black tapes on it, lined up looking through the viewfinder, so that you have a reference exposed on film as to where the lines appear to be through the finder.

Oh right.. I take it that's done in pre-production though, to save shooting the film and then finding that a lot of what you framed for just isn't there.

 

"So where?s Connery?s head gone?!"

 

I guess that would be kind of a pain, because you would then have to guess where the boundaries REALLY are.

Edited November 5, 2004 by Daniel J. Ashley-Smith

[Phil Rhodes]

Hi,

Yes, they'd normally shoot that at camera tests. Often it'll be used when you do telecine, since most modern machines can crop and pan and zoom, so you just set the telecine up for whatever the operator saw in the eyepiece. This is why it's becoming easier to shoot more or less any framing you want within the 35mm picture area and get away with it!

Different, obviously, if you're contact printing to release in cinemas.

Phil

[John Sprung]

Frame line charts are usually shot along with camera tests, or on the morning of the first day. The telecine operator cuts the charts off the first rolls and keeps them handy to set up the machine for your show every day. You need to shoot a chart on each camera, and re-shoot a chart if for any reason you pull and replace a ground glass. If you add cameras for a big day in the middle of the shoot, remember to chart them, too. It's a good idea to put the production name, date, and camera letter on the charts.

 

It's extremely important that the chart be shot carefully. We had a show on which they just leaned it up against something, so it was on an angle to the camera, and the top corners were closer together on film than the bottom corners. The telecine operator had to split the difference every time, and didn't always split it the same way from day to day. So, a poorly shot chart can do you more harm than good.

 

 

 

-- J.S.

[Guest Daniel J. Ashley-Smith]

since most modern machines can crop and pan and zoom

Wouldn't the resolution be cut drastically?

[John Sprung]

Wouldn't the resolution be cut drastically?

<{POST_SNAPBACK}>

Not drastically unless you zoom way far in, like taking the equivalent of a S-8 frame out of the middle of 35. Setting up to match the GG would never produce a measurable change in resolution.

 

 

 

-- J.S.