Longest automatic exposure?

[thegman]

Just a quick question - What is the longest automatic exposure the Bessa III/GF670 can do? On my ZI I think it's 7 seconds, I'd love longer, anyone know what the Bessa/GF670 can manage?

I'd like to know the same about the Mamiya 7 in fact, anyone know?

Cheers

Garry

 

[Jamie123]

It's 4s on the Bessa III. Here's the manual: http://www.chiifcameras.com/site2/images/Bessa_III_667_Manual.pdf

 

[thegman]

Thanks for the link!

4s is a little short for me, guess if I get one I'll get a little meter too.

Cheers

Garry

 

[Jamie123]

Thanks for the link!

4s is a little short for me, guess if I get one I'll get a little meter too.

Cheers

Garry

You can get a Gossen LunaPro which seems to be good for lowlight.

However, once you get into long exposure times you can pretty much start estimating based on experience as there's a lot of room for error.
Let's say the correct exposure for a scene would be 20s. If you misjudge the light and expose for 10s that's only half a stop underexposure. If you go over and expose for 1min that's still only 1 1/2 stops and should still be perfectly fine if you use neg film. And of course there's always the possibility to bracket exposures.

 

[thegman]

Unfortunately for colour, I very much like slide film, so I try to be as accurate as I can be...

I'll look at that meter though.

 

[Jamie123]

Unfortunately for colour, I very much like slide film, so I try to be as accurate as I can be...

I'll look at that meter though.

It really depends on what kind of long exposures you have in mind. If you're planning on doing night exposures it's no problem even with slide film. Pick your favourite slide film and shoot a test roll at different speeds under the lighting conditions you will generally encounter.

This way you'll probably be more accurate than a lightmeter as the meter doesn't account for reciprocity.

 

[John NYC]

The two best approaches I have found for long exposure night shots are:

1. Experience. You can really guess it once you have done it enough.
2. Get a DSLR. Set it to the widest aperature and the highest ISO. For instance, f/2.8 and ISO 3200. Put it on aperture priority mode and take a test shot of your scene. Convert the equivalent to whatever you are going to really use. So, if you are using large format 8x10 and you are going to expose at f/22 on 100 ISO film, this would be an 11 stop difference. So, if on your test shot the DSLR read 1/8 of a second for the shutter speed, you will need 11 more stops of light on the large format, or 4 minutes. But you really need more than that because with that long of an exposure, you will have some reciprocity failure of the film. So maybe you need another half or whole stop, so 6 or 8 mins.

After a while of doing number 2, you can start seeing it is pretty easy to do number 1. When you are talking an 8 minute exposure, being off by 10 seconds doesn't make a bit of difference.

 

[GoneSavage]

I think a decent light meter is all you need, end even then, (as Jamie says) there's a huge margin for error. My last batch of night shots were done using an unmetered TLR and a Sekonic L-358. Interestingly, there were times when the Sekonic just wasn't able to measure the exposure I knew I wanted—3:00 in the dark at f16 using velvia, for example. What surprised me was that all of my guessed long exposures turned out looking just as nice as my metered ones, even on slide film.

 

[thegman]

At present my exposures are not going much beyond 10 seconds, but I've got some ISO 25 film to use, and I'd like to use it at night, so I can see exposures going beyond 1 minute.

I've no intention at all of getting a DSLR, but a light meter is probably going to find it's way onto my shopping list I think.

 

[Jamie123]

At present my exposures are not going much beyond 10 seconds, but I've got some ISO 25 film to use, and I'd like to use it at night, so I can see exposures going beyond 1 minute.

I've no intention at all of getting a DSLR, but a light meter is probably going to find it's way onto my shopping list I think.

If you're going to use a lightmeter make sure you know the factor for reciprocity failure for the film you're using.

And, like I said, I'd look for a used Gossen Luna Pro (they're not available new) as it's got a much wider low light metering range than other meters.

 

[John NYC]

At present my exposures are not going much beyond 10 seconds, but I've got some ISO 25 film to use, and I'd like to use it at night, so I can see exposures going beyond 1 minute.

I've no intention at all of getting a DSLR, but a light meter is probably going to find it's way onto my shopping list I think.

Even a cheap digital point and shoot (as long as it has manual controls) will work with the technique I described.

But if going the meter only route, I'd definitely recommend getting one that has a spot meter feature, especially if you are doing distant scenes like cityscapes with a lot of lighting variation.

But, I think you will find that your experience after not that many shots will guide you just as well for anything over a minute.

 

[maddoc]

It is 32s with Leica M7, one of the reasons that I bought it.

This one is not an interesting shot at all but to test the AE capability at night. (32s (AE), f/8.0 on Tri-X, no correction of exposure)