Removing internal filters on Beaulieu ZM4008

[fdfco]

I have a ZM4008, from which I plan to remove the internal 85A and UV filters, as the acetate has degraded.
If I do this, and use a screw-in 85 filter on the end of my lens, how does this affect the metering / film speed?
I presume that, because the light reaching the TTL meter has passed through the screw-in filter, I leave the film speed setting at the film's rated speed(40ASA for Kodachrome 40 rather than 25), and use the meter as normal.
Is this correct?
Has anyone removed the internal filters? Any comments / recomendations?
Also, does anyone know where I can get a new rubber eyecup for this camera?

[Bjorn Andersson]

If you remove the internal filter, there will be some very important things you have to think of: You have to adjust the camera body!
WHY?
The distance between the C-mount and filmplane on a 4008 camera is NOT the same as camerabody whithout internal filter, like late 4008ZM4. You also have to adjust the ground glass, the lens must in most cases also be adjusted to the new situation.
If not, you will not have the crystal sharp frames on your film.
If the internal filter is damaged, dity or broken, there is probably more faults in your camera, very noisy, dirty/foggy viewfinder, high battery consumption or other things.
Do you know anything about when your camera was serviced last time, or the history of your camera?
The cost to remove the filter is low, you can do it by you self, but the adjustments that has to be done is nothing you can do at home.
The internal filter is very well protected against "dirty finger" when it is in right place.
Many camera-servicemen says; "it´s better to remowe the internalfilter". Do you know why?
Because they do not know Beaulieu cameras and they don´t have any spare parts, like new filters, therefor it´s easier for them to say this!!!!!!!!
This history I have heard to many times, from my customers over the years, since 1974 up till today, several hundred times has this been said. Another sad thing for all Beaulieu users in UK, is that you not longer have a Beaulieu service place in the country. All service has to be sent abroad, after that Bill Perry retired.
Last year was all his Beaulieu spare parts and tools shipped over to me here in Sweden.
But I can offer you all type off service to any Beaulieu camera or projector, also supply all Beaulieu accessories and cameras.

Bjorn Andersson
Beaulieu/Sweden

[fdfco]

Bjorn, thank you for your good acvice.
I do not know the history of the camera, or when it was last serviced, and I have not used it yet.
Following your advice, I will keep the filters in place, and see if I notice any problems when projecting. (At present I am only using it for home movies)
Forgive me if I am being stupid, but how does removing the internal filter affect the focus. Surely removing the filter does not affect the distance from the rear lens element to the film plane?
Thank you,
Mike Richards.

[Bjorn Andersson]

The internal filter behind last lens and filmplane, make that you have to have this distance 0,05mm longer than for normal C-mount. The filter "steal" this, the optical and metric distance is not the same in this case.

[Maurizio Di Cintio]

Hi, Bjorn, I'm a little confused: if by removing the built-in 85B filter, some precision in the collimation of the lens is lost, then how can one get perfectly sharp results when filming in artificial light, that is when you do not need that filter? Sorry, maybe this is a silly question but I've never owned this camera.
Also I would like to know whether this problem affects cameras with non-interchangeable lenses too. In other words, would I get better results with my Nizo 6080 AND an 85B filter screwed on the lens (after defeating the built-in one by means of the switch)? In fact I am afraid that all built-in conversion filters tend to degrade after so many years. What's your opinion?

Thanks a lot.

[S8 Booster]

What´s the point of disassempling the filter from the cam?
When it is in "lamp"/tungsten position (Beaulieu 5008MS is my reference) the filter is out of the light path anyway so it got to adequate to just turn it off; "lamp" / Tungsten position?

General rule:
Do not mess with fine engineered prescision equipment unless you are well qualified!

My..., cents.

R

[Bjorn Andersson]

The internal filter in a Beaulieu camera has two different parts. The W85, for daylight, the clear "UV" filter for Tungsten light. The "clear" one is only there to compensate the optical distance.

For cameras with non-interchangeabale lenses, normaly the filter is placed somewhere in front of the last lensgroup.

A zoom lens has five main parts:
Frontgroup, to adjust from infinity to shortest as the lens can accept.

The zoom, a part, where groups of lenses is moving depending of each others, for wideangle or telefoto.

The prism/beam splitter to viewfindersystem (not in C-mount Beaulieu).

The iris/diafragm.

The rear element, a group of lenses to project a perfect image at the filmplane/groundglass.

If you look inside for ex a Schneider 1,4/6-70 for Beaulieu. This lens has 16 lenses in several groups to make the work.

[jessh]

how does having the filter within the lens not cause the same problems with focus? wouldn't it change the optical distance between the elements? I am not saying you are wrong I just don't understand this and would like more explenation if you know and don't mind.

~Jess

[Bjorn Andersson]

When the filter is placed inside the Schneider lens, there is 7 lenses more before filmplane. Every piece of glass in a lens, whatever shape it has, konvex or concave, change the "optical" distance. If the filter is inside the lens this flat "lens" will not disturb. There is, as in this case, 7 lenses that still has to be passed before projecting the image at the film. But to remove the filter after the rear lens, when the "perfect" image is ready, will make it little out of focus. This is not seen so clearely on telefoto, as in wideangle.

[momotaro]

O.K. I have a Beaulieu 5008 and have an issue- the internal filter will not pull all the way out of the frame and makes an ugly line across the picture. The filter itself is clean, just sticking out into the shot. Not good. I understand that this filter needs to be in place, but was wondering how to adjust the little sucker so it won't screw up the shot?

Thanks in advance.

[aj]

Rotate the filterknob a considerable number of times does not work?

Does the camera have a feeler inside the filmcompartment? Pushing and releasing this may loosen things up.

Is the spring broken? Then you are stuck.

[momotaro]

I've tried to cycle the thing quiet a number of times, and I can see it move, but it never seems to move enough to get out of frame. I may just have to send the thing out to get it checked. It would be nice if they could just put a clear gel in there and call it a day.

Thanks!