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Contax AX

And only autofocus on 5,6 >and better!

--no, i used vivitar 600/8.0 cat. its not the sharpest but sharp. 450/4.5 would be better i guess. i did not compare. see my second earlier message.>
 
as mentioned in earlier messages some months ago, i have tested vivitar cat 600/8.0 in dim-light inside a store. and it worked although officialy 5.6 is the minimum.
 
The real criteria for getting focus is not so much the aperture, but the contrast of the subject within the area of the AF-Sensor. So with a low Aperture but good contrast you still can get in-focus pictures / AF while it's on the other hand possible with a bright lens in a sunny environment to not get into focus (although I must admit this happens rarly, but it happens!)

But a general rule of thumb is, that with lenses below f4 you will find more and more situations where the AF will not work as expected (although they will not show up freqently and possibly never if you only shoot Landscapes / Scenic stuff)

Mike
 
I think I'm off the T3 and onto the AX. I have two Hasselblad lenses: CFE 80 and CFE Super 250, f/2.8 and f/5.6 maximum, respectively. If the AX can focus with the 250, I'm sold. I really want to get a 35mm autofocus, and I think the AX is it (well, actually, I want a Rollei 6008 AF, but...).

SO, any input on using the AX with the Hassy lenses via the Contax Hasselblad Adapter?
 
Hi,

You can find back Craig's earliest comment in this Thread.

AX can basically focus on any lens(es) as long as it can adapt to AX body. It moves the film plane to focus. One thing it should be noted that it moved only 10mm max. If the lens requires more 10mm travel to focus from closest to infinity. User should have certain adjustment by himself.

Rgds,
Francis.
 
> Craig,

I have never used one of these adaptors but, as long as it positions the lens correctly for infinity focussing, you should be able to use it with the autofocus. That can really be taken for granted with the Contax adapter, otherwise why make it? I also think you may get the full advantage of the Hassy's higher speed flash sync of 1/500 sec if you shut down the Blad shutter and hold the Contax shutter open on B. If you then trip the Blad shutter manually you will get a high speed flash sync signal to manually trip a flash on auto, say a Metz. Autofocus and high speed sync at the same time. Otherwise, set the aperture on the Blad lens and lock it's shutter open (on B as well I suppose) so you can use the Contax autofocus, shutter and TTL ambient/flash metering. This will work in either aperture priority or manual. Regards,
 
>the AX can focus with the 250, I'm sold. I really want to get a 35mm >autofocus, and I think the AX is it (well, actually, I want a Rollei >6008 AF, but...). > >SO, any input on using the AX with the Hassy lenses via the Contax >Hasselblad Adapter?

what is your question? btw: http://www.zoerk.com does also offer adapters.
 
Gary,

> I have never used one of these adaptors but, as long as it positions > the lens correctly for infinity focussing, you should be able to use > it with the autofocus.

Lenses with slower apertures make autofocus difficult. I'd say that 5.6 is borderline. If it were 2.8, I'd say you're probably OK.

> I also think you may get the > full advantage of the Hassy's higher speed flash sync of 1/500 sec if > you shut down the Blad shutter and hold the Contax shutter open on B. > If you then trip the Blad shutter manually you will get a high speed > flash sync signal to manually trip a flash on auto, say a Metz.

How do you trip the shutter manually? How do you cock the shutter after taking the picture? I don't believe that will work. The only way to trip the shutter on CF lenses, that I am aware of, is from the rear of the lense, nothing external on a mounted lense allows you to do this.

Austin
 
Hasselblad leaf shutter is out of the question here--the shutter/aperture release/cock is a slotted shaft on the back of the lens inside the mount. What I'm looking at is autofocus with preset aperture down to 5.6. If I want, say, f/16, I have to let the AX focus at an aperture larger (smaller number) than 5.6, then manually stop down the lens, something all Hassy "C" mount (central shutter) lenses can easily do. (Note: Hassy "F" mount lenese do not have shutters and require the 200/2000 series cameras, which have focal-plane shutters). Zörkendörfer may be the answer for autoaperture, but I'm more interested in the focus. The possibility of expanding the system with Contax MM lenses, some of which are PRIMO, really appeals to me.
 
> Austin,

I have no solution to the specific points you raise, As I said, I haven't used the adaptor with a Blad lens. The issue you raise with apertures is consistent with my experience with autofocus with Canon EF, but it will depend on the low light sensitivity of the Contax sensor. It may give up at 4.0 or it may work at 5.6 and trying it out is the only way it will give us a definitive answer. Craig will have to work this through unless someone else on the group has tried the combinations he has in mind. I wonder if Joseph Yao has tried this out?

As to the CF lenses, they are the most recent generation that I know of but I had thought some of the earlier lenses had external releases for the shutter to enable their use on bellows. Perhaps someone else can enlighten us on this. Regards,

Gary
 
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