Anyone actually tested 64T in a 40/160 camera?

[Mogzy]

Just a question, has anyone actually tested the exposure latitude of E64T in a 40 160 only camera?

I have used

K40
VNF 125T
Plus X 100D
Tri X 200D 160T

all in a Sankyo EM-30XL and all turned out brilliantly. Even the VNF 125 rated at 160 (a difference of 35ASA) should have come out underexposed, but it looks great!.

Using 64T (which rates at 40ASA in daylight with the filter wheras K40 rated at 25ASA daylight with filter) assuming the camera rates it at 40 and not 160 initially, you have only a 15ASA difference. Is this slight over-exposure noticable?

[Film-0-Matic]

nice that is great info.
but i have no idea how it will turn out.

85B Filter = 40ASA
you can screw 85B on the lens(if it has thread)
set the camera for Tungsten while fimling in daylight
fool the camera it is filming without 85B.
now the camera will give correct aperture when using 64T

no idea what im talking about...

[richard p. t.]

quite right, that's quite wrong!
64 asa film is 64asa. A 40asa light meter is 40 asa. There is no fooling!
It makes no difference if you use an external or an internal colour correction filter. Remember that with 40/25 and with 64/40 colour film, the second figure in each case is only the effective asa ONCE YOU HAVE SUBTRACTED SOME LIGHT DUE TO THE COLOUR CORRECTION FILTER! The film is still 40 (k40) or 64asa (64t) respectively and the light meter still reads incoming light and adjusts/indicates the apeture for 40asa sensitivity - its just that there is less light due to the use of the filter.
By the way, it is problematic to speak of a such-and-such asa difference. It is better to speak of a difference in f-stops. For example, the 15asa difference in sensitivity from 40 to 25 is the same difference in sensitivity as the 60asa difference from 160 to 100 or the 120asa difference between 320 and 200, etc. In all of these instances the difference is 2/3 of a stop.

[super8man]

nice that is great info.
but i have no idea how it will turn out.

85B Filter = 40ASA
you can screw 85B on the lens(if it has thread)
set the camera for Tungsten while fimling in daylight
fool the camera it is filming without 85B.
now the camera will give correct aperture when using 64T

no idea what im talking about...

Almost, the 85B will simply color correct by 200Kelvin over the internal 85 filter. Otherwise, assuming the camera is TTL, the meter is still calibrating for 40 (or more likely, 160).

Close. A for effort and showing your work.

[Film-0-Matic]

A 40asa light meter is 40 asa. There is no fooling!

assuming the camera is TTL, the meter is still calibrating for 40

indeed it wouldnt work..LOL
the TTL will only RE-compensate for the loss of light!
BUT it might work on a cheaper non TTL camera.
not?

[Shion]

Well, if both Plus-X 100 and Tri-X worked properly, your camera is not 40/160-only. It could be 40/160/250-only, with correct daylight filter implementation (like the Canon 514XL-S), or it could be some other variation.

7240 (VNF- 125T/80D) was notched for 100T/64D, if I'm not mistaken... but because many of the lower-to-mid range cameras did not recognise this notch, many registered it as 160T/100D.

Either way, the over- or under-exposure with VNF is only 1/3 of a stop. With 64T, there's either a 2/3-stop over-exposure (40ASA), or a 1+1/3-stop underexposure (160ASA). Either is more significant than the 1/3-stop error that occurs with VNF.

-Bon

[Shion]

Do any of the labs doing 64T offer push/pull processing options? This issue is mentioned so frequently that I'm starting to think there's hordes of people out there with cameras that meter 64T as either 40ASA or 160ASA...

-Bon

[David M. Leugers]

When I get around to shooting some 64T probably next spring or so, I plan to adjust the exposure on my Sankyo and/or Nizo cameras to compensate for the 1/2 stop difference from 64T and K40. This is easily done by the adjustment screw provided for this. I know this doesn't help a lot of camera owners, but there are plenty of cameras around that can do this. Might be worth it if one plans on shooting a bunch of 64T and wants auto exposure. I usually set exposure manually with a good meter, but there are times I like auto exposure and one part of a cartridge can verify correct adjustment through some test shots bracketing different amounts of adjustment.


David M. Leugers

[richard p. t.]

Pull processing of 64t to 40asa is offered by Martin Baumgarten (Platesburg Photographic Services) and I believe the 'Reversal Lab' in the Netherlands.

[Mogzy]

Well, if both Plus-X 100 and Tri-X worked properly, your camera is not 40/160-only. It could be 40/160/250-only, with correct daylight filter implementation (like the Canon 514XL-S), or it could be some other variation.

-Bon

Inside the camera it says

Daylight 40 160
Type A 40 160
Type G 40 160

So I suspect it's a 40 160 only. It does have a switch inside which automatically removes the filter when a daylight cartridge (including Plus X and Tri X) is inserted. I wish instruction manuals explained this more clearly!

[Shion]

Inside the camera it says

Daylight 40 160
Type A 40 160
Type G 40 160

So I suspect it's a 40 160 only.

It ought to be, with specifications like that, but I don't see how any truly 40/160-only camera could properly expose both Tri-X and the newer 100asa Plus-X.

It may well be that the instruction manual isn't going into enough detail. Maybe it only lists 40 and 160 asa films because they were the only stocks being offered at the time, even though the camera can recognise others as well.

-Bon

[Cheezy]

I have shot several 64T rolls outdoors with my Beaulieu 4008 ZM II (set to 40 asa because on daylight setting) and Bauer S709 XL. The Bauer obviously read it as 40 asa, and was thus supposed to overexpose it by at least 1/2 stop and gave great results. The overexposure is barely noticeable. On both cameras I was more shocked by the grain and the blueish tint of the film than my exposure. It was all telecined and graded so we were able to make up for the color and exposure differences but then I put some K40 in the telecine and… I will definitely miss K40 a lot!

[audadvnc]

I have shot several 64T rolls outdoors with my Beaulieu 4008 ZM II ...On both cameras I was more shocked by the grain and the blueish tint of the film than my exposure.

Cheezy, were you using the internal 85 filters on your cameras? Try again with the proper 85B filter, that should clear up the bluish tint part. Proper exposure is your only hope for grain reduction.

[Cheezy]

Yes, it was all using the built-in filters. 85B should be ok on the Beaulieu since that camera has independent ASA setting knob, but what about the Bauer? I know this topic has been discussed many times but nobody seemed to agree. The Bauer obviously knows when the built-in filter is in place, thus reading light as if I were using 25 asa film. If I screw an add-on 85B filter on the lens, I have to remove the built-in 85A, right? The camera will then read full 40 asa… which is finally the way the Beaulieu is supposed to handle the 64T in daylight conditions. So where's my problem?
Just what f-stop difference is there between 85A and 85B?

[r.sk8s]

Cheezy,
The E64 is 40asa with the 85B. It becomes 40 asa due to the 85B filter that reduces the amout of light that enters the lens by 2/3 of a stop. We rate it at 40 to compensate for the 2/3 loss of light from the 85B. If the Bauer reads the E64 cart as 40 asa it will overexpose by 2/3 a stop. If you keep the internal 85 filter disengaged the camera will indeed think you have 40 asa film loaded, until you screw on the external 85B filter. Once you put the 85B filter in front of the lens, the built in light meter will react in the same way it would when you flip the switch and engage the internal 85 filter. Your auto exposure will open the iris 2/3-1 stop to compensate for the loss of light from the filter. It does this in reaction to the filter, internal or external.

So you step outside with the Bauer loaded with the E64 cart, internal 85 disengaged. The camera's internal meter thinks you have 40 asa loaded. The E64 is still 64 asa. Without the filter your camera will expose for 40 asa, the film is 64 asa. This will result in an overexposure of 2/3 of a stop and a very blue image. In you attach a 85B filter to the front of the lens. it will reduce the amount of light entering the lens by 2/3 of a stop. Problem solved...sadly no. The internal light reter will react to the loss of light from the 85B by opening the iris 2/3 of a stop. This puts us right back to where we started.

Here is another way of looking at it. We step outside with The Bauer and E64 with the internal 85 disengaged. The Bauer light meter says f8 The film is 64 asa the camera thinks 40 asa. The correct exposure for 64 asa would be f8 2/3. f8 is an 2/3 stop overexposure. With the 85B the E64 becomes 40 asa. So the f8 from the Bauer's light meter is now correct. The problem is once the 85B goes on the lens the Bauer's meter will read f5.6 1/3

I hope this way too lengthy explanation helps. It may hurt as much as it helps. :? With most negative stocks a 2/3 stop overexpose is not a problem at all. In fact I always overexpose negative by at least 2/3 of a stop. Most negative stocks have more lattitude for over and under exposure and react well to overexposre. Reversal is the opposite of this. Reversal reacts well to a slight underexposure and has little lattitude for over and underexposure.