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Contax N-Digital - the ultimate Contax Fan-Test....


N-Digital - the ultimate Contax Fan-Test....

Since we are waiting already so long for this digital camera, while the competition is introducing already their second generation digital SLR, you can see now slowly, who is really a Contax Fan and who is not

Because nobody knows exactly when it will really come in the store, we end up in speculating about the fabulous advantage of the full-size chip of the N-Digital – we do not have anything else to do anyway.

So I try to start a thread to get some interesting facts about the technology and pro and cons of the N-digital, before we can see one in the store. I am new to digital photography, so I will not talk here a lot about this, hoping that someone smarter than me will catch the line….

I do not want to go into details about the specs., knowing, that the last word is not yet spoken and changes might still come in the future. In the download-section you will find some information about that and if something changes, I will post it in the “news” folder.

What might be interesting are the advantages and disadvantages of a full-size chip vs. the 2/3-solution of the competition. If you see, how aggressive Nikon and Canon is coming now with their new models, it makes sense to think about pro and cons. That helps to decide, whether you still want to wait for Contax or start shooting today with another brand name on the body – and of course lenses. The N-digital will be more expensive anyway. This is for sure and everybody who thinks/hopes differently is dreaming (sorry to be so harsh).

You will always have to pay a premium, if you want to have Contax/Zeiss. It does not matter, whether there is another brand, which gives you the same quality body (if that would be the case with the N-digital). It just matters, whether you can put Zeiss glasses in front of it. This is the name of the game and it is up to you to decide, whether you agree and pay the bill, or you don’t and then you buy something else. Leica is doing the same – maybe even more extreme.

I am not a digital expert, so I can not tell you as of today, whether the Zeiss lenses are making a remarkable difference, assuming everything else would be equal. I think at this stage we can expect that there will be not everything else equal for the next 2 years. In my opinion there are right now too many different approaches in chip, software and camera design to be able to give an objective judgement. Probably “real life” tests will be the only satisfying way to find an answer – maybe you find it amusing, but I still hope, that there will be an N-digital this year (2002). So I am concentrating now just on the chip-size and someone more knowledgeable could help us with some comments out.

First you have a change in focal length, if you are not using a full-size chip. It is like a multiplier. If you compare full-size chip and a 2/3 chip, this is like a factor of ca. 1.6 to the “normal” focal length of a full-size chip. This is good news for people who use tele-lenses and bad news for fans of wide-angle pictures.

But there is also an advantage for the 2/3 chip. Because of the smaller size, you basically cut off the corner (in a circle) of the lens, which means you are just using the better designed (in image quality) centre of the lens instead of the often worse corners. If you are using a full-size chip, the full radius of the lens, as we know it from analogue photography, is used. That means all the inferior corners influence also the final picture. So the 2/3 chip can be an elegant way of hiding the potentially mediocre design in the corner of lenses. And this could be also a reason, why all new N-lenses have bigger filter sizes. I think with the quality of the Zeiss lenses I can live easy with the “corners”. At least I did live with it happy for the last years in analogue photography.

This is not yet the end of the story. As a Contax fan, you hope of course that there are also some more positive effects of full-size chip then “just” the real use of wide-angle lenses. Otherwise why is Contax putting so much effort in it, if they could have had it a lot easier using a 2/3 chip? And there is at least one, which is in my opinion a pretty important one.

If you think about the “multiplier effect” of the 2/3 chip, there is also another important effect. It influences also the image quality if you want to enlarge your photo. This effect is almost as big as the switch from 135 to medium format. The multiplier is almost the same factor of 1.6x. If you are using a full-size chip and you are looking at the MTF charts of lenses, then you see line-pairs/mm (lp/mm) of 10, 20 and 40. If you are using a 2/3 chip, you must basically imagine the curves of 16 lp/mm, 32 lp/mm and 64 lp/mm. The difference between the lines is more or less always the same ratio. Obviously the image quality will be worse at 16lp/mm then at 10lp/mm. That means, if you want to enlarge a negative (I guess everybody wants that), you have worse image quality because of the need of enlarging the negative more often to get the same final print size.

Everybody knows, that medium format is superior to 24x36 in image quality if you enlarge to the same final print size and using the same film. Therefore I expect a “wow-effect” of the N-digital pictures, compared to the 2/3 chip-competition if you enlarge to the same print size.

It would be interesting to know, by how much a smart combination of hardware, software and chip could improve this disadvantage of the 2/3 chip or maybe even enlarge the quality difference in favour of the full-size chip.

For technical details: http://www.contaxndigital.com/
When I was shooting digital I specifically chose the Sony Cybershot digital because they used Zeiss Vario-Sonnar lenses. The reviews of the Zeiss equipped digitals always commented on the significant resolution benefit that high quality optics delivered.
You get comments like "...we were a bit surprised by how well the DSC-F505V did on the resolution test, given its 2.66 million effective pixels - It actually showed higher resolution than some 3 megapixel models! We attribute this to the same razor-sharp lens the original F505 was noted for."
http://www.imaging-resource.com/PRODS/F505V/505VPI CS.HTM
"The F707 performed very well on our "laboratory" resolution test chart, turning in some of the highest resolution figures we've measured to date. It started showing artifacts in the test patterns at resolutions as low as 1,000 lines per picture height, in both horizontal and vertical directions. We found "strong detail" out to at least1,200 lines. "Extinction" of the target patterns didn't occur until about 1,650 lines. Wow, that's resolution!"
http://www.imaging-resource.com/PRODS/F707/F7PICS. HTM

I would expect that similar improvements would be seen in the NDigital compared to other digital SLRs.
Contax N Digital – A Quick Review

Perhaps some of you are interested in the new Contax N Digital, so here is the story from a demo session I attended at Calumet - a photo dealer in Edinburgh, Scotland. You can see more Contax pictures all taken in Scotland at my web site www.cvscotland.com and if any of you have pictures of Scotland you might think we can use, drop me an e-mail.

Commercial break over – back to the show - It was a digital photography demonstration, with cameras from several different manufacturers there. The shop had a studio set up with a model and you could use any of the cameras available to take her picture.

There were 2 N Digital cameras, with an assortment of lenses, and a full 645 kit as well. My main interest was in the N Digital, which as I’m sure you all know by now has the world’s first 35mm full size (24x36mm) chip. The camera has been under development for at least a couple of years since first being mentioned in the media, and rather than go through all the details, I’ll pick out the main points, and tell you about my experience with the camera. There has been a lot of speculation about whether it would appear at all, but it’s real, and here are some results.

The full size chip is the camera’s big selling point. This chip which is made by Phillips has already been used in digital camera backs for some large format cameras, but this is the first application in an SLR 35mm body. All the other 35mm cameras from Nikon, Canon etc use a chip which is smaller than the coverage of the lens. In effect this means that you get a magnifying effect – a bit like having a permanent teleconverter on the camera. Most are about 1.4 times, which means for ex&le a 300mm telephoto is nearer 400mm in terms of the magnification of the results.

Where this has a real effect is at the wide angle end, where a 17mm wide angle is nearer 21mm in terms of it’s coverage, so it is impossible to get a really wide angle view.

When you put a lens on the N Digital, there is no magnification effect, and a 17mm lens gives a very wide field of view – exactly as you would expect.

If there is a negative side to using the chip, the large format digital camera backs are set for a “film” speed of 100 ISO and this cannot normally be varied. The Contax and Phillips engineers have extended the ISO rating from 25 ISO to 400 ISO – and this was the subject of a specification change just before the launch of the camera. More about the effects of that later.

The other problem about using a chip instead of film is internal refection. The shiny chip reflects more light back to the rear element of the lens than conventional film, which has more of a matte finish on the emulsion side. If you have a look at the N series lenses, instead of being able to see the rear element clearly, there is a rectangular metal mask to help cut down this internal reflection.

Apart from the obvious advantages of digital, such as previewing the photo immediately after taking it, it is also possible to vary both the ISO speed and the type of image recording format from frame to frame, and record it all on the same CompactFlash card. This for me would mean I would not need to use two camera bodies – I always keep a different film speed in each at the moment.

To show off the capability of the camera, the Contax people had taken some studio shots which were of a stainless steel knife with a serrated edge on a leather wallet. These were enlarged to 500mm x 750mm and taken both with the N Digital and also the digital back on a 645 of exactly the same subject - I could not tell the difference between them, and the quality was outstanding even at that size of enlargement.

They also had a series of A4 size enlargements taken on the lowest compression Jpeg format (largest Jpeg file size) at speeds from 25 ISO to 400 ISO going up in steps 25/50/100/200/400 ISO of exactly the same subject. It was only if you looked really closely that you could see very slight noise on the image at ISO400. In practical terms, it was very useable between 25 and 200 ISO.

All digital cameras suffer noise at higher ISO, but usually not until you get to 800 or 1600 ISO speeds, so this could be a problem for some users. For the studio photographer used to a fixed speed digital back, the N Digital would be a big improvement. Most of my pictures on my RTSIII’s are taken between 25 and 400 ISO, but I would say the camera would not be too good at low light or sports photography where a high ISO was required, and from talking to the Contax people it is not aimed at that market.

Because camera was being used for demonstration, it was switched on all the time, and was running off a cable to a mains adaptor to conserve the batteries. Unlike nearly all other digital SLR cameras, the N Digital uses 4 conventional AA size batteries. This means they are easy to replace, and relatively cheap compared with say Nikon batteries which are in a unit shaped to become part of the camera body when clipped in place. A charger and upgraded batteries will be supplied with UK spec. N Digital cameras, along with software on CD and a few other bits and pieces.

The camera handles really well, but having an RTSIII, I'm not used to the auto focus - there are just so many functions available, there will be a big learning curve for anyone buying the camera. Quality of finish is up to the usual high standard, with all the major controls in the correct place, and many such as the focus selector and shutter button duplicated so the camera can be used for vertical shots.

The metering and auto focus is pretty much the same as the N1, but obviously there are many more controls to deal with the digital image.

I tried taking pictures using Jpeg, Tiff and RAW image formats, and you will see the results of some of these on the site. In order to process the RAW files - (these are maximum quality with no in camera processing) you need the Contax software to "develop" them - I have tried the Nikon software, and it doesn't work! I should have these sorted shortly, and that will give a much better idea of the quality of the image. As soon as they are done, I’ll upload the images.

I also tried changing the ISO speed, but as the chip is optimised for 100 ISO my guess is that’s where the best results will be.

The colour temperature is important in digital shots, and although I did change the settings for inside and outside using the white balance control, again this is an area where using a Nikon D1 I have seen a big improvement in colour balance by overriding the auto setting. It’s a bit like getting used to the characteristics of a particular film, and will take some experimentation to get right.

I did some studio shots, and a couple out of the studio door of the car park, but it really needs a few day of playing around to get good results, and I’m sure I could do better with more practice.

The studio shots relied on the in camera exposure – two flash heads, and a sync lead to the camera – exposure was 1/125 sec on manual. The preview showed the initial shots to be a couple of stops under exposed, so I opened the lens up a bit and it was fine – I lightened the background a bit more in Photoshop The car park shot was metered off the ground (grey tarmac), the exposure locked, and then the shot taken as you see it and has not been manipulated at all. I was interested to see if the highlights on the cars would burn out, but they seem OK to me. Lens used for all shots was 24-85mm Vario Sonnar.

There is a histogram facility, and Exif details – exposure, lens used etc - I did not get the chance to try this in the time available.


This is a stunning camera which can produce very high quality results. It’s biggest limitation is the restricted ISO speed, but if you can live with that, and are prepared to devote plenty of time to learning the capabilities of the camera, they I’m sure you would be happy. It might be an idea to take your bank manager out for a meal, and after a couple of glasses of wine tell him you need a loan – not to buy a car, but a camera – it’s an expensive piece of kit.

The lens range is being expanded, and on display was an 85mm f1.4 and the 17-35mm Vario Sonnar. A 400mm f4 Tele-Apotessar is under development, as well as some pretty high speed zoom lenses – sorry but I promised not to reveal any more.

Watch this space for more info. As soon as I get anything I'll post it for you all.
I just bought the N-Digital, and tried very hard to familiarize it. However, one problem confused me: When I used "C" for continuous shotting, it crashed every time. Now I can only use "Single" shot for photography. I don't know if it is a firmware problem for all N-Digital, or my own problem?
Hi Robert,

I guess we are all eager to see more comments/images from the N-Digital. Could you comment on your experience with it in the field in a few days and upload maybe some images?


I really enjoy taking picture with N Digital in these couple of days except some problems bother me: 1) I can't take pictures by switch to "C" for continuous shooting, the camera will crash. 2) The battery exhaust very quickly, my experience is 4 AA can only take about 40 pictures 3) We can't download firmware to update it by ourselves.
What is the maximun print size at 300dpi that can be made from an N-Digital image?