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#1 Mark Williams

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Posted 20 February 2006 - 06:34 PM

My camera is an arri BL 16mm

Shining a lens through the ground glass and projecting the Markings on the wall, I noticed in the grey far outside edge of the image what appeared to be a curvature.. I checked everything and think it could be the lens?

When the lens is zoomed in or out it seems to make a difference..IT is always present though.. This made me think that with this particular lens zeiss T3 Zoom Would I be able to use it for Super 16 OR Ultra anyway?

BUT

And importantly..

Could the the safe area and the bit beyond be giving me enough room to have the telecine pull right into the very edge of the gate as it is? If I framed for 16:9

After all the safe area is only a concern when emulsion or hairs,dirt etc get stuck which would most likely be the bottom of the gate You would only have the sides to worry about.. I just wondered by utilising the entire gate would this give you anywhere near Super or ultra.. If you asked the telecinist to pull out AS FAR as the gate allows? :)
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#2 David Mullen ASC

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Posted 20 February 2006 - 07:05 PM

I'll be curious to see what other people's responses are, because I couldn't understand most of your post. I'm guessing you're asking if your zoom lens will cover an enlarged gate, but I'm not sure.
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#3 Mark Williams

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Posted 21 February 2006 - 12:35 AM

[attachment=1025:attachment]

I'll be curious to see what other people's responses are, because I couldn't understand most of your post. I'm guessing you're asking if your zoom lens will cover an enlarged gate, but I'm not sure.

Hi David

No my gate is not enlarged Apologies if not explained very well ! Its just a standard gate Im trying to see how much MORE that could be used in the safe area of this standard gate.. I have attached a piccy of my gate sorry about the Ultra overlay But I was trying to see how much 0.7mm would eat into my gate If I filed it down for ultra.. Which you can see overlayed..

Thanks..
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#4 Stephen Williams

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Posted 21 February 2006 - 03:30 AM

Could the the safe area and the bit beyond be giving me enough room to have the telecine pull right into the very edge of the gate as it is? If I framed for 16:9


Hi,

A telecine should be able to see full camera apeture, that will give you a slightly larger frame than normal TV projection.

Stephen
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#5 Mark Williams

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Posted 21 February 2006 - 04:30 AM

Hi stephen

Yes But how Much extra? Enough extra to negate the need for conversion?

David

I have projected my gate onto a white wall that allows you to see the image.. I have enclosed Some pictures that would show the area you could get onto the telecine So just in your opinion how much does this get you to super 16mm by using the entire gate?

The reason I ask is because I assume in telecine or blow up they would use the safe image area only..

BUT if you specified use the whole gate by pulling back and blanked it off for 16:9..

Possibilities?
[attachment=1026:attachment]
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#6 Mark Williams

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Posted 21 February 2006 - 05:54 AM

I have tried to upload other pics..

I seem to have run out of global space for attachments..

When trying to upload large Attachment filesizes IF they are rejected the Global quota removes that amount.. even though I havnt posted it? when I tried to upload another it tells me to remove the previous Upload which I cant access because it was rejected..

Probably Im doing something wrong. I dont fully understand how the forum layout works yet..
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#7 Boris Belay

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Posted 21 February 2006 - 08:03 AM

Mark, Regarding your telecine question, that's (more or less) strictly between you and your telecine facility... What I mean is that the problem with modifications like Ultra-16 is that you have to convince your telecine operator to go there with you, ie, find, buy, or make a gate that corresponds to your image area. It doesn't seem like such a big deal, but it's for you to do the convincing : either they will be nice and feel like experimenting a bit with a spare part, or else they will think there is a market in an up-and-coming format like Ultra-16.
But as you will see from previous threads about Ultra-16 on this forum, this is an uphill battle : a lot of people balk at the very idea (and I mean, the idea itself) of modifying anything on their cameras that deviates from the accepted standard. Also economically, while the Ultra-16 modification make sense for people who have a small camera budget (like you : you have the camera, the lens (?), and all you need is a file...), this same fact means labs may not be interested in that 'market segment', annoying people with crazy ideas and no money !
I personnally like the idea of U-16, in part because I do my own transfers so I could easily modify my telecine projector to U-16, but your main problem will be to convince whoever does your transfers to modify their equipment for this format.
I know some people on this forum were interested in doing U-16 transfers for people in your position, so if it's convenient for you to send your film away, look through the U-16 threads and you'll find them.
They should also be able to confirm whether your lens will handle the widened format. Your pictures are so small, it's hard to tell whether there are optical aberrations on the edges.
-B
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#8 Mark Williams

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Posted 21 February 2006 - 09:17 AM

Hi Boris

Well I think the Ultra 16 is a good idea and worth doing providing it is succesful Im kinda confused a little about ultra To me it seems it would be better than super 16 as you can have sprocket holes both sides..

Problem is and Im not sure why but there does seem a reluctance perhaps because super 16 has such a large following..

I think I will leave Ultra at least for now and try to Max the standard gate see if that can yield results.. The way I see it is from the TV Safe area to the sides of the gate is the same as shaving the sides off for ultra although the sides would have no safe area..
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#9 David Mullen ASC

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Posted 21 February 2006 - 10:16 AM

Remember that a telecine transfer of 16mm to 4x3 video uses the whole negative, not just the TV Safe Area. The TV Safe Area (or Title Safe) is just to show you a typical amount of compensation for TV overscan, i.e. the 10% loss on all edges for most CRT monitors. But almost the whole 16mm frame is transferred to fill 4x3 TRANSMITTED.

So there really isn't more negative on the 16mm frame to be used to make a 16x9 transfer, not without enlarging the gate.
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#10 Mark Williams

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Posted 21 February 2006 - 11:20 AM

Remember that a telecine transfer of 16mm to 4x3 video uses the whole negative, not just the TV Safe Area. The TV Safe Area (or Title Safe) is just to show you a typical amount of compensation for TV overscan, i.e. the 10% loss on all edges for most CRT monitors. But almost the whole 16mm frame is transferred to fill 4x3 TRANSMITTED.

So there really isn't more negative on the 16mm frame to be used to make a 16x9 transfer, not without enlarging the gate.

Even the brown border area in my attachment? is transmitted?

So TV transmits ALL 16mm frame Data But leaves out the edges.. SO I guess if the telecinist pulled out to say ULTRA's frame width and encompassed undeveloped film.. It would capture the black of unexposed film which would be telecined along with the full 16mm frame for TV who would transmit the black area But the bordered full 16 frame would be shown.. without the intrusion of the undeveloped film area..Because of overscan?

SO you could still get a benefit equivilent to Ultra?

Edited by Mark Williams, 21 February 2006 - 11:28 AM.

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#11 David Mullen ASC

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Posted 21 February 2006 - 12:12 PM

Here's a diagram I drew:

Posted Image

The 16mm camera aperture is 1.37 : 1. 4x3 TV is 1.33 : 1 so there is slightly more lost on the sides than the top & bottom, but it's not significant. Inside what gets transferred and transmitted is the safe area for TV overscan.

The only advantage of Ultra16 and Super16 is when you need a wider image than 1.33 / 4x3, like for a 16x9 video transfer.
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#12 Mark Williams

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Posted 21 February 2006 - 12:56 PM

Here's a diagram I drew:

Posted Image

David Thanks for that BUT Im getting even more confused because either your diagram is completely innacurate or my ground glass is?

The 16mm camera aperture is 1.37 : 1. 4x3 TV is 1.33 : 1 so there is slightly more lost on the sides than the top & bottom, but it's not significant. Inside what gets transferred and transmitted is the safe area for TV overscan.

The only advantage of Ultra16 and Super16 is when you need a wider image than 1.33 / 4x3, like for a 16x9 video transfer.


It seems I cannot upload any more attachments because I have reached my global limit therefore I cannot show diagrams I have made..

BUT

You have drawn three marked out areas in your diagram.

The safe area..

The transmission area..

The aperture AND 1:37

This is your drawn diagram above which is different to my projected gate picture a few posts back.. You can see the safe area then another area.. I assume this would be the transmission area and quite a large outside edge that would be big enough for a widescreen image to fit within..

If my Gate is not showing the transmission area and is instead showing markings for something else Perhaps you could let me know?
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#13 Freya Black

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Posted 21 February 2006 - 04:56 PM

The safe area shows you how much of the view is tv safe. What TV safe means is that the area within that boundry will display on all TV's. The area outside of that boundry may still display on some tv's, just not all of them. The transmission area is the area that would be transmitted or presumably stored on tape during telecine.

This would be the maximum area normally viewable on a TV.

So:

transmitted=max viewable area
tv safe=min viewable area

The area viewed on a TV can therefore vary between transmitted and tv safe. It just depends on the t.v. being used! :(

love

Freya

Edited by Freya, 21 February 2006 - 04:57 PM.

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#14 David Mullen ASC

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Posted 21 February 2006 - 04:57 PM

You have to understand that your groundglass can show you more than the camera gate exposes for.

Take a look at some of the charts here:
http://www.cameraser...tech/format.htm

You need to draw a framing chart that exactly lines-up to your groundglass marks, shoot it, and then look at the film to see what gets exposed exactly.

Bottom line is that if your camera is regular 16mm, it's probably not exposing more information than that -- the gate is exposing a 1.37 16mm frame -- so you'd have to get the gate enlarged if you wanted more exposed.
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#15 Patrick Neary

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Posted 21 February 2006 - 05:00 PM

Hi-

Hope I'm not butting in here with more confusion, but it seems like you're asking about the gray area outside the aperture lines in the BL viewfinder? If so, that's just a safety area to let the operator see what's going on just out of frame (boom poles, light stands, etc.) it doesn't record to film because the film gate isn't that large.
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#16 Mark Williams

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Posted 21 February 2006 - 05:14 PM

Hi-

Hope I'm not butting in here with more confusion, but it seems like you're asking about the gray area outside the aperture lines in the BL viewfinder? If so, that's just a safety area to let the operator see what's going on just out of frame (boom poles, light stands, etc.) it doesn't record to film because the film gate isn't that large.


Hi Patrick

Yes it does record to film and this is exactly the area in question. The reason I know that it must record to film is because the image in my attachment a few posts back has been projected onto the wall if you look closely you can make out the pattern of my wallpaper.. So Im seeing the groundglass through the gate which is the hole whose size will determine what you see..

So what you see projected is in fact what is exposed..
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#17 Mark Williams

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Posted 21 February 2006 - 05:34 PM

You have to understand that your groundglass can show you more than the camera gate exposes for.

Take a look at some of the charts here:
http://www.cameraser...tech/format.htm

You need to draw a framing chart that exactly lines-up to your groundglass marks, shoot it, and then look at the film to see what gets exposed exactly.

Bottom line is that if your camera is regular 16mm, it's probably not exposing more information than that -- the gate is exposing a 1.37 16mm frame -- so you'd have to get the gate enlarged if you wanted more exposed.

Thanks for that David

According to the format guide pdf regarding ground glass

Page 6
EXTENDED Viewing space
Additional area aroung the outer frame lines to check for incoming objects ie Microphones Parts of this additional area might not be visible on the negative..

This is saying might not be visible BUT surely if I can see this area projected on the wall then it would be visible? to the gate? HOW could it not be?
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#18 Patrick Neary

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Posted 21 February 2006 - 05:36 PM

well, no- I'm assuming you shot a light through the eyepiece and projected it through the lens to the wall (or the reverse)? If so, then you are only looking at the groundglass image bounced off of the camera's mirror shutter- the gate isn't part of the equation at all.

Like Mr. Mullen wrote earlier, shoot a framing chart, then look at the developed neg-

hope this helps-
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#19 Mark Williams

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Posted 21 February 2006 - 05:47 PM

well, no- I'm assuming you shot a light through the eyepiece and projected it through the lens to the wall (or the reverse)? If so, then you are only looking at the groundglass image bounced off of the camera's mirror shutter- the gate isn't part of the equation at all.

Like Mr. Mullen wrote earlier, shoot a framing chart, then look at the developed neg-

hope this helps-

Patrick

Yes I see where I may be going wrong.. The shutter mirror can show more picture area than the shutter can see.. I still dont understand why Unless the shutter mirror is magnifying the image perhaps.. BUT the arri pdf said this area MIGHT Not be visible which also means it might.. I think its still worth investigating..
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#20 David Mullen ASC

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Posted 21 February 2006 - 05:48 PM

This is saying might not be visible BUT surely if I can see this area projected on the wall then it would be visible? to the gate? HOW could it not be?


Sure, the extra picture area may hit the gate, but the gate is a GATE, an aperture, a rectangular hole cut in metal that only allows a certain area of film to get exposed, blocking out the rest. It's the last thing before the film, whereas the viewfinder takes the image from the lens before reaching the gate.

So if you want to expose MORE of the negative, you need to enlarge the gate.
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