Mamiya 7, looong exposures, cold?

[timeUnit]

I've tried 5 minute exposures in temperatures around 10°C + windchill, which worked fine. I'd like to do 30 minutes to an hour, but now the temperature is below 0°C here. Will the electronically controlled shutter handle that? What happens if the batteries are drained when the shutter is open? Disaster?

The manual for the camera doesn't tell me much...

Thanks!

 

[David H. Bebbington]

No experience of long exposures with the Mamiya 7, but I think as a rule of thumb the average electronically-controlled shutter will get through a set of batteries in about 5 to 6 hours of time exposures, certainly less at low temperatures.

 

[jd callow]

On the mamiya 6 when the batteries die during an exposure the shutter closes. I have had this happen many times. It is very easy to not hear the shutter close and therefore not know that the shot failed. Worse is the fact that the batteries can 'regenerate' sufficiently to allow you to start a second exposure -- which will also fail. This has happened to me as well.

On the flip side I have taken 15 and 30 min exposures in the cold w/o issue. I have also taken multi hour exposures indoors under warm conditions w/o issue.

 

[Paul Sorensen]

My Mamiya 645 at about -5 to -10 C (I am guessing, well below freezing) went through batteries really fast. I just took the dead battery, put it in my pocket to warm it up and traded them back out when the other one died. I was able to make it through the evening, probably three or four hours, with the two batteries. Mamiya also made or makes a dvice for the 645 that allows you to carry the battery on your body and connected to the camera by a wire. There may be a similar device for the 7.

Well, there is a similar device for the 7, here it is at B&H for $87!

 

[timeUnit]

Thanks for this great info!

Paul,
87 USD is a bit steep... I can get LOTS of batteries for that... It couldn't be too hard to build a device like that. You could even parallell connect a couple of batteries, carry them on me, it would last forever!

Thanks again. I'm heading out.

mrcallow,
I'll be keeping my ears open...

 

[gwatson]

If it's any help, I used a Mamiya 7 in Norway last winter (v. cold). Had no problem with the battery, but after a couple of hours it seemed that the shutter machanism froze. I'd trigger the shutter and the button stayed down for a second or two. I'd warm the camera up for half hour and it functioned as usual. I assumed that the leaf shutter in the lens had frozen, but when I dev'ed, everything was fine. The camera does not use a great deal of power keeping the shutter open. If you are shooting 30 min exposures, keep camera close to your body before hand (battery in pocket) and then clad the camera in a scarf while it is on the pod. Sounds daft but it will work.

Geoff

 

[Aggie]

I didn't know the mamiya 7's had to have batteries to work the shutters? I have the 7II and took the darn battery out. I use a spot meter to meter and set everything manually. I have not had a single problem.

 

[jd callow]

Aggie the 6 has lenses in shutter (just as the 7/7II) and those shutters are electronic. The 6 will not work w/o bats I'd be flabbergasted if the 7 did.

 

[timeUnit]

I didn't know the mamiya 7's had to have batteries to work the shutters? I have the 7II and took the darn battery out. I use a spot meter to meter and set everything manually. I have not had a single problem.

That is a "new" feature in the "II" model in that case. The 7 will not work at all without a battery, which really sucks. Now I have to worry that the camera will die on every exposure...

 

[timeUnit]

Ok, so I was out for three hours yesterday night. Haven't processed the film yet, but it seemed that the batteries worked fine for those three hours. On the last exposure, 13 minutes, the battery died at 12 minutes. I had a spare battery, and put it in to take one last shot. Suddenly the camera didn't work at all. I figured the spare battery was too cold as well, and packed my stuff. Today when I checked the camera out I found I had put the battery in backwards... Those darn batteries look the same on both ends! At least in the moonlight...

Well. The exposures varied between 5 and 26 minutes and it seemed to me that the battery held up until that last shot. I listened carefully for the sound of the shutter closing at the end of of each exposure. I think I heard it on each of the shots...

I'll see soon enough.

Aggie,
I just read the Mamiya 7II manual. On several places it says: "The camera will not function without a battery." On page 30: "Precautions for Bulb Photographing
• When bulb photographing, the battery is consumed. A new alkaline manganese battery is durable for about 3 hours, silver oxide battery and lithium battery for about 7 hours. When the battery is fully consumed, the shutter will be closed automatically."

I find it very strange, not to say unlikely, that your camera works without a battery. Are you sure that you haven't confused your camera models?

Thanks for all the info. I will show some of the shots if they turn out...

*henning

 

[timeUnit]

Pics turned out OK. The shutter seems to have worked fine on all shots.

Here's 12 minutes at f/5.6:
Dead Link Removed

Too bad I shot on defective Fomapan 100. Spots all over the pic.