New Zeiss ZF lenses

[wang]

Not yet, but I have my money on the ZF 25 2.8. Its size, weight and short focusing distance suggested it will be as good as the C-Y 21 2.8.

 

[grumpoid]

Hi,

I notice that the ZF 25/2.8, whilst seeming to be a brand new design shares the same disingenous 'true' focal length of 26mm with the old C/Y 25/2.8...maybe not so new after all?

cheers Steve.

 

[wang]

Well, the new ZF 25 2.8 has two more lens elements and it is 100g heavier than the C-Y 25. The old C-Y 25 2.8 suffers from colour aberration particularly at the corners. Why do they add two more elements to the new lens ?

I do not know the truth until we get the side to side comparison of the prints. You do not expect Zeiss to add two more elements for no reasons. All camera lenses are basically like a single unit of convex lens with real focal length, so light rays has the net effect to converge. When you look at the lens elements, you will see that some of them are convex and some concave and the sum of which becomes the ultimate convex lens. Light rays has to go through pathways converging and diverging in a number of times with the net effect on converging.

As the number of lens elements increase, the process of changing from converging to diverging and vice versa increases. Why do Zeiss increases the cost by increasing the number of elements ?

If light rays converges once, it will cause a degree of chromatic aberration. This refractive error can be corrected by diverging the rays.

If you look at the design of Contax Zeiss 21mm 2.8 C-Y, you will see that it has 15 elements with both diverging and converging lenses. It is a very much corrected lens system with the lowest chromatic aberration even at the corners. The design with large number of elements explain one of the reason why this lens is so good.

We expect the new ZF 25mm 2.8 to be good because it has two more elements.

Another reason why it is good lies in its ability to focus near. It has the shortest focusing length made by Zeiss much shorter than the old C-Y 25 2.8. Short focusing requires converging power from the lens and good lenses have to do this without optical error. If it is from Zeiss and it can focus this kind of short distance, it is definitely good.

 

[wang]

Does anyone want to celebrate with me ? We ought to get together sometime and start a party for this.

It started with not getting anywhere from Kyocera. I read about the postings in the past concerning the gradual deterioration and final termination of the Contax systems. There were lots of outcries with unfulfiled expectations. It felt like hell. It started with her non-compliance with customers. No matter how good the Zeiss lenses are, with a partner like this there is simply no future.

We are all Zeiss lovers but we have passed a very hard time. It was a time that we were left with no products but second handed only. The prices of the lenses were going up and some reaching the roof.

Other companies are not sympathetic with us. Our expectations were high with Sony but again we were left behind.

There are now 6 ZF lenses and I looked at them with passion. I am sure these are the answers from Zeiss for those who were left behind.

The most expensive one is ZF 100 f2. The design of this lens is even more complicated than my Contax 85 1.2. In 1995, this lens was sold USD4k in Hong Kong. I suppose nowadays the price of lenses is going down thanks to Zeiss. 100 macro has an irreplacable role in 35mm and cannot even be replaced by medium format. It is just not practical to use medium format in my practice, even if I had the FujiBlad.

On the other hand, good 100 macro do give a medium format feel. For ex&le, if you shoot 1/3 of the face with this lens, you will get part of the face with stunning degree of realism. The image quality of this small format resembles medium format in every way. In fact, the degree of visual informations provided have very good scientific and clinical applications. I can certainly assure you that good 100 macro can see better than human eyes. The images it produce can overwhelm you with details which are being ignored when you look at it (with the human eyes). In fact, a doctor can make more accurate diagnosis by looking at the image from 100 macro than seeing the patient.

Using C-Y 100 2.8 with Canon is just not practical. I normally use f8 and stopping down to f8 can make you drift away from the right point of focus. We also found that Canon sensors do not reproduce the human skin tone very well. On the other hand, Sony do better in this respect even though she is also using Bayer kind of sensors. I would expect Nikon to do better than Canon in this particular field since she is sharing sensor with Sony.

With an f2 it will focus more accurately than its predecessors. It is also one stop better.

So I am looking forward for the day to combine this lens with the Nikon full frame digital. I just can't hardly bear my 350D any longer.

People might say Zeiss is never as good as Leica in producing f2. This is certainly true with ZM35 f2 and this is the lens that you feel happy with in f2.4 and up but not below. We expect a much better f2 in ZF 35 2 than the Biogon.

I am certainly very happy with my C-Y 28 2 when playing in the short distance. I would be even happier if I can play in a shorter distance and on top of this ZF 25 2,8 is optically better.

ZF 50 2 MP is also amazing. It is the most complicated normal lens Zeiss has ever designed.

Both ZF 50 1.4 and 85 1.4 are better than their C-Y counterparts.

Good lenses will stay with people for a very long time. One ex&le in history is Leica Summicrom M50 2, it stayed for more than 50 years and it still amazes me. I am sure these ZF lenses will stay on for a very long time.

Well, good night.