Projection lenses

[Fons Baerken]

Working on contrasts is the key to specific bokeh,

from 2013



D800, 35mm f/1.4

[Toby]

Just for the record, here is another one, first pretty much SOOC with only a bit of exposure correction, and then with my usual processing routine.

[Erik Lund]

Thank you for the sample and the reference to the other thread confirms the look of the out of focus areas, in the sample image you provided the upper left show quite obvious the difference

[Toby]

The sharpening plugins that I use work on a certain radius, and that often coincides with the radius of details in the bokeh, so of course the bokeh is emphasized. If you look at the sharpening of the details in the face of the statue you will see the same kind of sharpening, which I find desirable. But the basic character of the bokeh is not really changed. Have a look at this, which is without any sharpening

[Erik Lund]

,,,But the basic character of the bokeh is not really changed....

Yes, a distinct enhancement of the basic Bokeh character

[paul hofseth]

on replacing my old colorplan with the recalculated version I was tempted to use the coronavid exercise allowance to snap this local tree.(no sharpening, only levels when changing from the raw file)


p.

[Dr Klaus Schmitt]

Is this the P2 version of it, or do you mean the Super-Colorplan (which also came in two versions btw.)?

[paul hofseth]

the recalculated version was the supercolorplan, this is actually labelled p2, which means that the optics is placed in a different spot in the same size tubus in order to match the plastic type projector built after leitz bought the zett projector factory and stopped making the "battleship" type pradovits.

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[MEPER]

I have the Colorplan lens shown on picture. I never got a projector for it so only use was for looking at film on light table which it was quite good at.
Do you think such a lens can be used for taking real pictures?
Which kind of adapters do you use?    .....it must be real homemade?

It has a deviation figure specified (+0.2mm in this case). I was told it was if you used multiple projectors for overlapping images then you could select lenses with same deviation. Lens has been on the shelf for many years.

[Dr Klaus Schmitt]

I have the Colorplan lens shown on picture. I never got a projector for it so only use was for looking at film on light table which it was quite good at.
Do you think such a lens can be used for taking real pictures?
Which kind of adapters do you use?    .....it must be real homemade?

It has a deviation figure specified (+0.2mm in this case). I was told it was if you used multiple projectors for overlapping images then you could select lenses with same deviation. Lens has been on the shelf for many years.

OF COURSE NOT, it delivers horrible results!! :LOL:  You have to love shallow DOF and bokeh..   See for yourself here on my album: https://www.flickr.com/photos/kds315/albums/72157668904112563

I have developed some modular mounting system here (ebay parts and some from Rafcamera.com also on ebay): https://photographyoftheinvisibleworld.blogspot.com/2015/09/how-to-modularily-mount-projection-or.html







It is an excellent lens and quite better than the normal Colorplan based on its MTF chart, also the color transmission is better.

Leitz stated in its brochure about it:

""Advanced optical computation methods led to the SUPER-COLORPLAN-P2, whose optical performance surpasses even that of the renowned COLORPLAN-P2, to the point that its imaging quality is comparable to that of the APO lenses for our LEICA M and LEICA R cameras. Its highly corrected optical system provides excellent resolving power, brilliant illumination, true color fidelity, uniformly high contrast rendition and unequalled sharpness across the entire image area.""

[MEPER]

Thank you for the information. I got the idea.
Can see my Leica projection lens is a "real lens" so should probably not just be put on a shelf. If the lens has "M-lens quality" it is a cheap way to get such quality. These lenses are not that expensive as I remember and maybe even cheaper today as most people does not use slides projectors. It is very rare I use it. But quite fun when it happens. 

I have a 6x6 slide projector. The latest Rolleivision 66. There is an adapter system so it can also take 24x36 cassettes.
I read somewhere that a 24x36 lens like the Leica could be used on the 66 using an adapter but I never looked for it as I used the AV-Apogon 120/2.8 which I got together with the projector. It requires a bit longer distance to the screen for 24x36 but it worked and the 120/2.8 seems to be a nice lens also for 24x36. How good it would be as a photographic lens I don't know. It is quite large in diameter.
But an interesting idea to use these lenses on a camera. 

[dickb]

Your Leica projection lens has a mount with a diameter of 52.2mm. A system as described by Klaus is very nice and convenient to use. But if you just want test it quickly another option is a set of cheap chinese manual extension rings. These come in (at least) two diameters, 60mm threads for Canon EF mount and 57mm threads for Sony E and eg Minolta MD - I think 57 for Nikon F as well, but I don't own any of those. The inner diameter of the 57mm tubes is a decent match to 52.5mm projection lenses, especially when you use a thin flocking paper inside the tube. This makes a surprisingly decent sliding focus tube. The helicoid mentioned by Klaus is more precise of course.

I have two Rollei 6x6 150/2.8 projection lenses, a Heidosmat and an S-Heidosmat. Its tubes are 74mm in diameter. This won't work with the 65mm adaptation from RAFCamera as it is too wide. My lenses however can be unscrewed from this tube, it has a 71mm thread. So for your Leica lens to work in your Rollei projector you need some sort of adapter from 52.2mm to 74mm. I don't know of any, but I'm sure such an adapter can be made.   

[MEPER]

I found the manual for the P66 dual and it seems there is a part no. for the 35mm lens conversion set.
Other places in the manual they talk about a "reducing tube".
Maybe conversion set is with 35mm condenser and everything and may be the reason for not trying to get it and be happy with the 120mm and 6x6 condenser system. If worked great with 24x35 also and the only projector I had which was 100% sharp from corner to corner. The Leica projectors I had......like P150, P300 or P600 IR had some small alignment problems.....if you looked very carefully. I never had a "tank version" like P2002. 

Do you know if the real 65mm conversion kit used to end up with M42 mount using the Leica lens...….the set screws to fix the lens for infinity focus…..does the set screws go deep into the metal tube of the lens?
 

[dickb]

I found the manual for the P66 dual and it seems there is a part no. for the 35mm lens conversion set.
Other places in the manual they talk about a "reducing tube".
Maybe conversion set is with 35mm condenser and everything and may be the reason for not trying to get it and be happy with the 120mm and 6x6 condenser system. If worked great with 24x35 also and the only projector I had which was 100% sharp from corner to corner. The Leica projectors I had......like P150, P300 or P600 IR had some small alignment problems.....if you looked very carefully. I never had a "tank version" like P2002.

 

Well, the 35mm condensor would be nice if you felt the need for more light when projecting 35mm slides. If not the reducing tube is the only part you need to use matching 35mm projection lenses. There are several tube diameters for 35mm projection lenses though, and the original reducing tube may reduce to a different diameter than you need for the Leitz lens. My 35mm Rollei lenses are in 42.5mm diameter, but they may have used different sizes as well.

Do you know if the real 65mm conversion kit used to end up with M42 mount using the Leica lens...….the set screws to fix the lens for infinity focus…..does the set screws go deep into the metal tube of the lens?

There isn't a fixed conversion kit for any specific lens, there are parts you mix and match to suit your lens and camera. I for one don't use the 65mm versions, but 58mm as I already had several parts for it. A kit would consist of a ring to fix the projection lens to a helicoid, the helicoid itself and an adapter between the helicoid and your camera of choice.

Most (but not all) rings for fixing the projection lens to a suitable thread have an internal metal strip, protecting the projection lens from the set screws and distributing the clamping force.

The total length of adapters and helicoid must be short enough that you can get infinity focus. Ideally you get the longest helicoid that will just allow you to do that. Short helicoids have a short focus range, longer ones are much more convenient. 

[MEPER]

Thank you for the explanation.
Will see if I get curious enough to try out the Leica 90/2.5 on a camera. Then I will ask Dr. Klaus to guide me for parts that will work in my case.
Nice feature that set screw does not go directly into the lens but clamped via a metal band.