ND filter (fixed, vario, cokin?) for Mamiya C TLR suggestion?

[kl122002]

I need ND filters for my Mamiya C TLRs. Should I go with fixed , or vario ND filters? Some lens also needs thin rim filters(like 180, 65) , which brand has thin rims ?

And Is there any cokin adapters made for Mamiya ? I have the old Cokin A filters on shelf and they still usable. I just don't want to waste them.

 

[Sirius Glass]

I prefer multi-coated glass filters over gels since they are more rugged and last longer.

 

[AgX]

That high-build issue only is related to vario-density ND filters. And here Heliopan offers as alternative a "slim" mount.
However only for metrical treads.

But you indicate that your Maniya got a special filter mount.

 

[Maris]

I use variable ND filters but definitely not on my Mamiya TLR. Why?

A variable ND filter is a stacked pair of polarising filters that attenuate light according to how much their polarising axes are crossed. A small turn of one with respect to the other can make a surprisingly large change in transmission density. The way around this potential error is to use through the lens light metering which my Mamiya TLR cannot do.

A variable ND filter is also an active polariser in its own right. The effect on the image cannot be seen in a TLR unless the filter is transferred from viewing lens to taking lens in exactly the same orientation; very tedious as a on going photographic technique.

A fixed density ND filter avoids these problems. And the other kind of ND filters, the graduated type, are not really practicable on a TLR either.

There is one situation where my Mamiya TLR is ideal for ND filter use and that is when I employ an ultra dense 10 stop filter for long exposures of daylight scenes. The viewfinder stays bright, clear, and focusable while the taking lens is very much in the dark.

 

[kl122002]

I use variable ND filters but definitely not on my Mamiya TLR. Why?

A variable ND filter is a stacked pair of polarising filters that attenuate light according to how much their polarising axes are crossed. A small turn of one with respect to the other can make a surprisingly large change in transmission density. The way around this potential error is to use through the lens light metering which my Mamiya TLR cannot do.

A variable ND filter is also an active polariser in its own right. The effect on the image cannot be seen in a TLR unless the filter is transferred from viewing lens to taking lens in exactly the same orientation; very tedious as a on going photographic technique.

A fixed density ND filter avoids these problems. And the other kind of ND filters, the graduated type, are not really practicable on a TLR either.

There is one situation where my Mamiya TLR is ideal for ND filter use and that is when I employ an ultra dense 10 stop filter for long exposures of daylight scenes. The viewfinder stays bright, clear, and focusable while the taking lens is very much in the dark.

Thanks for your help. That has cleared up my mind. I would definitely go with fixed ND filters.

 

[grahamp]

The thin rim filter requirement only applies to 49mm ones where you also have some sort of filter on the viewing lens, and/or use a Mamiya slip-on lens hood. If those two constraints are not applicable, most 49 screw-in type will work. You may need a suitable screw-in hood too.

With 46mm thread lenses you might be better off using a 46-49mm stepping ring, as 49mm filters of less used types are easier to locate than 46mm. And 40.5mm for the older lenses can be harder still.

Years ago there was a design for a device that mounted a Cokin filter holder over the viewing lens, and then allowed it to be slid the 50mm needed to cover the taking lens. Personally, I have never needed graduated or polarizing filters enough to go that route.

There are tricks for using polarizing filters with non-single-lens reflex cameras, not just TLRs. Just a matter of motivation

 

[kl122002]

The thin rim filter requirement only applies to 49mm ones where you also have some sort of filter on the viewing lens, and/or use a Mamiya slip-on lens hood. If those two constraints are not applicable, most 49 screw-in type will work. You may need a suitable screw-in hood too.

With 46mm thread lenses you might be better off using a 46-49mm stepping ring, as 49mm filters of less used types are easier to locate than 46mm. And 40.5mm for the older lenses can be harder still.

Years ago there was a design for a device that mounted a Cokin filter holder over the viewing lens, and then allowed it to be slid the 50mm needed to cover the taking lens. Personally, I have never needed graduated or polarizing filters enough to go that route.

There are tricks for using polarizing filters with non-single-lens reflex cameras, not just TLRs. Just a matter of motivation

Its real overcasting everyday , and that could made shots like 1/125 with f/22 on the bright mid day with ISO100 film. I hope ND filters and PL filters could help.

I have read the older posts and noted the same info about the cokin, but it seems it has been lost in these years.

 

[grahamp]

The Cokin-style adapter was never produced commercially to my knowledge. It was a slotted plate that was clamped to the lens pair, and held the mount for the graduated filter or polarizer. It starts opposite the viewing lens, and is then slid over the taking lens for the exposure.

I would expect some obscuring of the viewing lens because of the typical size of these filter systems.

Something along these lines for 49mm or larger polarizing filters should be possible, and would be smaller than a unitdesigned for 100mm square filters.

I remember reading the original article in Photon (UK magazine), but that is about as far as it went. Current 3D printing devices were not around in the 1980s.

 

[fpd2]

This was the Cokin adapter I believe: https://www.iconpublications.com/photon/aug96/mamiyacfil.html

I've been thinking about the same issue, as a Yashica TLR user. In reality, I used the Cokin point-and-shoot plastic adapter for A series and mounted it under the camera on the tripod. I also used Cokin A series polarizing filter handheld in front of lens shade.

I may design and print a suitable adapter soon. The way I see it, you would want to measure your grad filter position on the viewing lens and transfer it to the taking lens without messing up. I'd say, Bay I cokin Adapter with a 1mm scale on the side, plus hand etched 1mm interval scale on the side of your Cokin filter.
Alternatively, instead of using scales, one could use a screw to clamp the filter in place to prevent moving, when the whole assembly is moved down to the other lens.
Just some ideas.

 

[grahamp]

Nice to see the link - I had lost it when Photon went out of publication. I will update the Mamiya TLR Summary.

The idea was to position the filter in the Cokin mount over the viewing lens, then slide the Cokin mount over the taking lens, thus retaining the orientation. It would need the Cokin stacking hood elements, as Mamiya slip on or regular screw-in type wouldn't work.

The extra step to reposition the filter for exposure, and resetting for viewing would probably annoy me, but I don't use adjustable filters very much.

 

[fpd2]

My first attempt. Fits pretty well, may add a lever to the shade, to make it easier to disengage from the lens, since it is latched pretty solid.