Hi

Just a question to see what the average is. I am now swapping them out before any large shoot.

About 20-40 rolls.

Also discovered this week that its probably wise to take them out when travelling as the shutter can be pressed down in the bag causing it to beep non stop.

No idea what effect that much drain has on batteries o erring on side of caution.

M

blackiceuk wrote:

> Hi
>
> Just a question to see what the average is. I am now
> swapping them out before any large shoot.
>
> About 20-40 rolls.
>
> Also discovered this week that its probably wise to take
> them out when travelling as the shutter can be pressed
> down in the bag causing it to beep non stop.
>
> No idea what effect that much drain has on batteries o
> erring on side of caution.

To answer the question in your subject line: "never"
But then it looks like I shoot a _lot_ less than you do :P
I may shoot thirty rolls a year and I'm still using original
batteries in both of my TL120s.

The subject of TL120 battery drain has come up before and
I've posted on it before. I have done several measurements
on the camera starting with
http://tech.groups.yahoo.com/group/MF3D-group/message/301
and most recently with
http://tech.groups.yahoo.com/group/MF3D-group/message/1663

My conclusion (based on the shutter drawing 28ma) is that
the batteries should easily cover six or seven hour
exposures. I also expect the batteries would sustain around
twenty hours of continuous meter use.

I have implemented a shutter-lock on my TL120s
http://stereo.thurstons.us/ShutterLock.htm
to limit the number of times the shutter fires in my pack.

--
John Thurston
Juneau Alaska
http://stereo.thurstons.us

> To answer the question in your subject line: "never"
> But then it looks like I shoot a _lot_ less than you do :P
> I may shoot thirty rolls a year and I'm still using original
> batteries in both of my TL120s.

ahh. I did 27 last week in Prague. Thankfully processing is 1/2 price to my local lab.

> The subject of TL120 battery drain has come up before and
> I've posted on it before. I have done several measurements
> on the camera starting with
> http://tech.groups.yahoo.com/group/MF3D-group/message/301
> and most recently with
> http://tech.groups.yahoo.com/group/MF3D-group/message/1663
>
> My conclusion (based on the shutter drawing 28ma) is that
> the batteries should easily cover six or seven hour
> exposures. I also expect the batteries would sustain around
> twenty hours of continuous meter use.

Any major shoot I plan on replacing them. For the extra 3$ in costs its worth it. I just use the used ones in a pen light I have so no wastage and batteries are fresh.

> I have implemented a shutter-lock on my TL120s
> http://stereo.thurstons.us/ShutterLock.htm
> to limit the number of times the shutter fires in my pack.

Cool - cheers.

Mark