Canon DS8 exposure problem. Help!

[Ugo]

I have two Canon double super8. 36 hours since now I'll leave and I have to choose that one i'll brig with me.
This is the problem: this morning, by a simple test, I noticed the exposure of these cameras is different. About two stops!!!! One of that doesn't work well.
The only working item I have here is a Leicina special. I'm sure about the perfect exposure of this leicina.
The Canon DS8 # gives the same exposure of the Leicina. The Canon DS8 #2 gives two stops more than the other.
My question is: is it possible the Canon DS8 and the Leicina work with the same exposure value?
The Canon has a shutter with open angle of 165° and exposure time of 1/52 at 24 ft/s. I dont know the value for the leicina. In an old post in this forum someone wrote:
162° open angle and 1/55 for the Leicina special.
viewtopic.php?f=1&t=8842&p=71843&hilit= ... gle#p71843

Please, help me...

[Actor]

I'm sure about the perfect exposure of this leicina.
The Canon DS8 # gives the same exposure of the Leicina. The Canon DS8 #2 gives two stops more than the other.

Seems to me you've answered your own question.

[richard p. t.]

I can't remember how the reflex system of the Leicina works, but I think it is a beam splitter type like the vast majority of super 8 cameras and also the Canon DS8. If it is a beam splitter type (which I think it is) then it would be a safer bet to take DS81. However, if the leicina has a proper mirrored shutter and 'blinks' in the viewfinder with every frame shot, then it has a different reflex system to the Canon DS8. This would mean that it lets more light in, so would yield a more closed apperture (higher numbered) than the Canon DS8. You mention that the DS82 gives 2 stops 'more' - I assume you mean a lower number/bigger apperture. This could be the right direction for a Canon DS8 to deviate from a Leicina if Leicinas have a mirrored shutter. But I don't think they do (you can check) and if they don't then take DS81 ... and know that in future you must do a test first!
good luck with it,
richard

[ECNtoo]

Make life simple. Get a light meter and test against it.

[Actor]

Make life simple. Get a light meter and test against it.

Wrong! See the thread I started "Internal vs. external light meters."

I've worked out two methods for calibrating light meters. Unfortunately, both involve processing the film. If you're in a hurry, as Ugo apparently is, there's no time.

I may post the two methods in a separate thread sometime.

[Ugo]

Thanks a lot for your answers. The Leicina hasn't a mirrored shutter (that's is inside the Beaulieu).
So I think I may use the Leicina special like "touchstone".
This morning I ran other tests. I simulated some shots with the Leicina and the Canon DS8 #1 for the same objects in the same time (just few seconds to change camera in my hand). In every condition the exposure values were the same.
The Canon ds8#2 gives 2 stops more: it means instead 5.6 it gives 11!
I think the #2 is the wrong camera.
Tomorrow morning I'll leave for a two week holiday. The Canon DS8#1 will come with me, togheter tree ds8 100' (30 mt.) rolls of Velvia 50D.

and know that in future you must do a test first!

Right!! shame on me...