Contax 645 auto bracketing with MFDB

[lowep]

My attempts at using the auto bracketing control on my Contax 645 with eMotion MFDB attached are not working.

After reading the instruction manual I thought that all I would have to do is to flip the a.b.c. switch to either 0.5 or 1.0 and press the shutter three times - but when I do this I just get three identical exposures.

I have tried this with different exposure options (M, aperture priority, etc) and different release options (S,C, 2 second delay).

So either I am doing something wrong, this setting does not work with my MFDB, or (please no..) something is wrong with the camera.

Usually when I run into technical problems the first option is the most likely.  

Everything else seems to work fine including the exposure meter in the prism finder and the manual over/under exposure settings (so I can always do manual a.b.c.) but would like to clear up this mystery

[avelpavel]

Hi Lowep, here is the solution:

The Emotion adapter for Contax 645 works but not at 100% when it comes to send data between camera and DB, it must be a Sinar problem as we have both the same issues. I have Emotion 54LV which had big issues in the past, now I now how to deal with them.

If you put a small piece of tape on the adapter gold contacts, set the back on working as a X-Contact mode (like with a view camera) and connect the DB to the Contax 645 with the Sinar sync cable, everything works!

You can do Auto Bracketing and you can use the Contax 645 without that annoying "two pressing" of the fire button on the camera to wake the back... I found it very difficult to deal when I shoot people... let me know if you have the same slow problem with the shutter.

So if you want to use at full the Contax 645 you must deal with this, I have tested 2 different bodies and the same things happened. When I do still life shoot I use it without the tape (and I have Exif data on my files...), for people I go the "tape" way... (loosing Exif...).

I must confess I'm waiting to rise money for phaseone... too many issues with Sinar, we need to work on our jobs, not playing as tech gurus I think!


Let me know if you find out some news!

Roberto


_________________________
www.robertopastrovicchio.com

[lowep]

Wow this is really kooky  

Thanks for shedding light on this mystery that has bugged me no end.

How on earth did you find out what to do about this? I imagine you like Bell or Daguerre first experimenting with string on the tripod, then with hair in the cable release socket, then with vegemite smeared on the viewfinder... until finally you hit upon (of course!) sticky tape on the gold contacts. It is so obvious I don't know why I didn't think of it myself!

Have you considered maybe changing to a different back may cause just as many new problems as dumping the old one solves? I was surprised to find for example that upgrading to a digital back with more megapixels made hand holding more difficult; as I didn't see this mentioned in any of the manufacturers advertisements.

[avelpavel]

 

I had long hours asking myself why the back had problems... first I cleaned contatcs, then switched camera body... then I thought when I had the RZ and everything worked... but no contacts where present! I had an Emotion 75LV for a few months while the 54 was at Sinar to correct firmware troubles and yes I found it way better, and starting at iso 100 was a better thing. By the way it gives great results even at 800iso. I have found however that handholding a DB is not the way to go, only with fast flash sync and fast flashes... If you have time try to develop a Sinar raw file with Exposure, then use Raw Photo Processor... I have discovered a huge difference in quality and sharpness! RPP is right now the better... a bit difficult to use but great.

Roberto

Wow this is really kooky  

Thanks for shedding light on this mystery that has bugged me no end.

How on earth did you find out what to do about this? I imagine you like Bell or Daguerre first experimenting with string on the tripod, then with hair in the cable release socket, then with vegemite smeared on the viewfinder... until finally you hit upon (of course!) sticky tape on the gold contacts. It is so obvious I don't know why I didn't think of it myself!

Have you considered maybe changing to a different back may cause just as many new problems as dumping the old one solves? I was surprised to find for example that upgrading to a digital back with more megapixels made hand holding more difficult; as I didn't see this mentioned in any of the manufacturers advertisements.

[lowep]

I had long hours asking myself why the back had problems... first I cleaned contatcs, then switched camera body... then I thought when I had the RZ and everything worked... but no contacts where present! I had an Emotion 75LV for a few months while the 54 was at Sinar to correct firmware troubles and yes I found it way better, and starting at iso 100 was a better thing. By the way it gives great results even at 800iso. I have found however that handholding a DB is not the way to go, only with fast flash sync and fast flashes... If you have time try to develop a Sinar raw file with Exposure, then use Raw Photo Processor... I have discovered a huge difference in quality and sharpness! RPP is right now the better... a bit difficult to use but great.

Roberto

Thanks Roberto,

Tips like this are invaluable support for my sanity as I try to come to grips with a complicated new system. I will check out RPP. Meanwhile I am wondering what viable alternative solution their could be for hand holding and printing big just for the occasional (but sometimes critical) hand held shot

-- apart from film  

maybe:

shooting hand held with a high shutter speed like 1/250 to 1/500 sec

shooting hand held with a lower MP camera then using software like Genuine Fractals to increase the size of the print

shooting hand held with a high MP camera like the one I have then reducing the print size to the maximum print size of a lower MP camera to hide the evidence of camera shake

or....

mostly I work off a tripod so it is not a deal breaker issue for me - but it is @#$# irritating to discover, as I like the files that I get from the 33MP eMotion and would not like to be bogged down with an extra camera or cumbersome flash system  

[lowep]

Roberto,

I have copied and moved my reply to your comments about RPP to a new post here as my reply has more to do with image processing tools than cameras, lenses and shooting techniques. I am curious to hear what if anything the image processing gurus have to say about this program. Hope this is ok.