[therion]

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Dear friends!

I have problem with using rear filter mount inside Takumar 6x7 400/4 lens. I have thought it takes classical 77mm filter, as can be used for
normal lens in front of it. But I couldn´t mount such a filter onto 6x7 400/4 rear bayonet mount. It won´t fit , it was too thick.

Another question is, if it could be fitted, glass will be reversed and filter
will not work.

Finally I have disassembled Singh Ray Cokin sprocket ring filter, taken out glass and put it to rear mount of Tak 6x7 400/4 and it has worked.

thanks
Stefan

[desertscape]

Stefan, the 400 Takumar rear filter bay needs the filter holder to mount the filters successfully. It is a black threaded ring in which the filter screws into. If you do not have one, they are rare and hard to find. For some filters, it is possible to screw them into the back of the lens without the filter holder. Some filters will not fit the back of the 400 Takumar even with the holder. I have a Tiffen Warm Pol that does not fit because it is too large in diameter. I have owned this lens for 15 years now and have gone through some experiments; a home made front filter using a polycarbonate ring using polarazing sheet (bad idea). I then went to an uncoated rear filter (not sucessfull). Then went to a B+W multi coated rear pol filter with mixed results. Now I only use a B+W 105mm polarizer up front. I hate to use ANY filter in the rear of this lens because of reflections showing up on film. The 400 is worse than the 600 and 800 Takumars with regard to reflections from the rear filter. The 105mm filter up front is not an exact fit because the thread is 108mm, so an attachment method must be figured out to attach it.

[therion]

Aha ok, I understand, so holder is needed? Where it could be bought? Directly from Pentax?

I think I will use my disassembled SinghRay, it is relatively easy to use and I have first roll of Velvia taken with it and no reflections at pictures!

thanks

[desertscape]

The rear filter ring is probably the most difficult accessory to find for the P67. If your setup works, no problems. Another reason why I didn't like the rear filter for the 400 Takumar was that one cannot rotate a pol filter unless you take the camera body off the lens.

[therion]

Maybe such a cheap 105mm filter could work in front:

105mm CPL Circular Polarizer Polarizing Filter 105 NEW - eBay (item 360263465203 end time Jun-16-10 08:00:42 PDT)

And make some adapter 108 to 105mm

[Ben_Edict]

Maybe such a cheap 105mm filter could work in front:

105mm CPL Circular Polarizer Polarizing Filter 105 NEW - eBay (item 360263465203 end time Jun-16-10 08:00:42 PDT)

And make some adapter 108 to 105mm

It depends on how you understand the word "work with". I probably has some polarizing properties. But I bet, it is not multi-coated as the seller writes, because filters that are really coated/multocoated usually state that on the filter ring and this one doesn't. And for this size the filter cannot be of high quality at that prize. It is simply impossible to make such a big polarizing filter in good quality for and end-user price like this.

So, what you get are two glass plates of whatever quality, uncoated and with the cheapest polarizing foil sandwhich in between. What you get for free also, are a lot of reflections and flareing (2 glass plates = 4 glass surfaces) and probably some IQ degradation from the rough glass surface. At best, the glass is flame polished, but not mechanically polished.

Do you need a polarizer for that lens at all? And if so, you want to achieve the typical pol-effect and you would want to make visible the quality of your lens, which is not a cheap one. I think, in that case, you should safe your money and buy something better.

And if you just want a filter for lens protection, you should preferably use a good, long lens hood instead, which gives usually enough protection and also increases contrast.

Ben

[desertscape]

The 400 mm magnifies any aberration from your front filter. A cheap filter is not the solution; I have done that. Get the best; one that is ground flat and tested for flatness. I suggest B+W.

[therion]

I need polarizer because I´m taking pictures of mountains in distance and just at 90 degrees to sun, so polarizing effect is strong. I´m not affraid of reflections because I do not plan to shoot against sun.

But thanks for Your advice, I will continue using glass from Singh Ray polarizer in rear mount.

[Ben_Edict]

I need polarizer because I´m taking pictures of mountains in distance and just at 90 degrees to sun, so polarizing effect is strong. I´m not affraid of reflections because I do not plan to shoot against sun.

But thanks for Your advice, I will continue using glass from Singh Ray polarizer in rear mount.

An uncoated or poorly coated filter will not only add strong "reflections" in the form of ghosting or visible flare. It will reduce contrast and as such also, what we perceive as "sharpness". So, even if you do not shoot directly into the sun or at another light source, I wouldn't use one, especially not a polarizer with its two glass plates.

Your SinghRay in the rear filter mount is surely more inconvenient, but also of better quality and will cause less problems.

Ben

[Pentaxuser]

Hi to all,
I have just bought a Takumar 600mm f1:4 from Hong Kong for my 67II and I am open for any hints.
It is a great lens, has a few disadvantages but for me it is worth the money I gave.
I do not (yet) use extensions, but the rear filter is problematic. If you use the wrong Filter in the Adapter-Ring, you won't come to
Infinite position. But what is the "right" Filter? Where can I get one? What sort of Filters did exist?
And I'm looking for outer Bayonet Adapters, e.g. for 645D or Canon DSLR for this lens...

[desertscape]

Have you seen my review of the 600? Here- SMC Takumar 6x7 / Takumar 6x7 600mm F4 Reviews - 67 Telephoto Primes - Pentax Lens Reviews & Lens Database

Be aware that any rear filter will push the focus further back and you will have to change your focus to compensate. Glass thickness on various filters is different, so the degree of focus change will be different also. When using rear filters, the DOF scale on the lens will no longer be accurate but then again, the DOF scale is not all that useful on this lens anyway. You must use a mult-coated filter in the rear of this monster because there is a real problem with reflection on the outer bay lenses. Use 77mm filters. There are several 67 to 645 and 67 to Canon adapters that have the outer bay tabs on them, so that the outer bay lenses can be used. I use a Zoerk 67 to Leica -R for my 600mm. There is a two piece extension tube set made for the outer bay lenses but they are extremely rare (maybe only 300 made?).