Is it possible to convert T to Bulb?

Max Pegler · Jul 16, 2017

Hi all,

re the Fuji GW 690 & GSW 690

Great cameras. The only thing I don't like is the T setting for landscapes.

So is it possible to convert T to B? I was wondering whether just removing the T's shutter interlock would mean the camera would close the shutter with a cable release in the conventional manner.

Yes I use the black cap method, usually successfully. A 30s exposure isn't a problem, but at 2s, I have more than a few images of half scene & half cap!

Thanks & regards
Max P

Arklatexian · Jul 17, 2017

Max Pegler said:
Hi all,

re the Fuji GW 690 & GSW 690

Great cameras. The only thing I don't like is the T setting for landscapes.

So is it possible to convert T to B? I was wondering whether just removing the T's shutter interlock would mean the camera would close the shutter with a cable release in the conventional manner.

Yes I use the black cap method, usually successfully. A 30s exposure isn't a problem, but at 2s, I have more than a few images of half scene & half cap!

Thanks & regards
Max P

On all of my cameras, "T" stands for "time exposure". With the shutter on "T", you trip the shutter and it stays open until you trip the shutter again at which time it closes. So, why would you want to use "B"? With the "T", you can make a two second to one week exposure if you want to. I am not familiar with your cameras but if they work like mine, I see no reason to go to "bulb" except to shoot using magnesium flash..........Regards!

Max Pegler · Jul 17, 2017

oldtimermetoo said:
On all of my cameras, "T" stands for "time exposure". With the shutter on "T", you trip the shutter and it stays open until you trip the shutter again at which time it closes. So, why would you want to use "B"? With the "T", you can make a two second to one week exposure if you want to. I am not familiar with your cameras but if they work like mine, I see no reason to go to "bulb" except to shoot using magnesium flash..........Regards!

On T there's two ways of tripping the shutter. Either change aperture or wind on some film. Unfortunately both induce some camera movement. The normal workaround is to put the lens cap on first, or cover with a black or cloth first, but these aren't ideal either.

shutterfinger · Jul 17, 2017

Looked at the instruction manual, says interlens shutter so its a Seiko or Copal leaf shutter and the answer to your question is NO.
The service manual https://www.manualagent.com/fuji/gw-690-iii/service-manual shows the shutter as a module. I would find it easier to get a different camera that works the way you want compared to trying to modify this one.

AgX · Jul 17, 2017

Max Pegler said:
On T there's two ways of tripping the shutter. Either change aperture or wind on some film. Unfortunately both induce some camera movement. The normal workaround is to put the lens cap on first, or cover with a black or cloth first, but these aren't ideal either.

But that camera shake issue would occur with a B-setting too. To avoid this one should use an apt cable release.
The only advantage a B-setting has over a T-one is with very short exposures.

Max Pegler · Jul 17, 2017

shutterfinger said:
Looked at the instruction manual, says interlens shutter so its a Seiko or Copal leaf shutter and the answer to your question is NO.
The service manual https://www.manualagent.com/fuji/gw-690-iii/service-manual shows the shutter as a module. I would find it easier to get a different camera that works the way you want compared to trying to modify this one.

Thanks!

John Koehrer · Jul 17, 2017

Way back in the days before dirt and Mary Forscher (?) was going you could get almost anything done. All it took was money.

Theo Sulphate · Jul 17, 2017

The choices as I see it:

- Use slower film and longer T exposure so the act of capping the lens is a smaller percentage of the total exposure time. I'm assuming you don't want to introduce a neutral density filter into the optical path.

- Open up aperture to f/8 or f/5.6 (which is probably ideal for resolution) and use a faster (timed) shutter speed --- this doesn't work if you really need expansive depth of field.

- Don't cover the lens with the cap, use something like a bowler hat to wap over the lens very quickly.

AgX · Jul 18, 2017

As posted in #5 I still do not understand the issue. Could someone make me wiser?

shutterfinger · Jul 18, 2017

Some people have 8 fingers and 2 thumbs while others of us have 12 or 13 thumbs. When you have multiple thumbs you have to develop above average dexterity to operate cameras.
A person with 8 fingers and 2 thumbs finds pressing a shutter release once the again in 2 seconds a challenge but pressing a cable release and holding it down for 2 seconds is a piece of cake.
In post #3 its stated to change the aperture or wind on the film to end exposure. Having never used a medium format camera like the GW I'm not familiar with its T setting but leaf shutters I am familiar with you press the shutter release a second time or turn the speed ring to a different setting to end exposure.
Even though I have thirteen thumbs I prefer B for times greater than 1 second but shorter than 5 seconds.

jacaquarie · Jul 18, 2017

I do not understand this either, not knowing the camera.
My experience with T has been one"push" to open shutter, one"push" to close. Would seem that with suitable cable release the"push" to open then release shutter could happen within time interval required. In my limited experiences since having learned large format shutters usually have T, would rather have a T setting and give up B option.
Why is it necessary to change apature or wind film to trigger shutter?

Theo Sulphate · Jul 18, 2017

My explanation:

On some cameras, the T operation is NOT terminated by simply pressing the release a second time - on such cameras, typically the T operation is terminated by moving the shutter speed away from T.

There's a problem with doing that if the exposure is short (a few seconds), because turning the dial introduces vibrations for a significant portion of the overall exposure time. In that case, B plus a cable release is the best choice. However, the Fuji does not have B. So, one is forced to terminate the T operation by moving the shutter speed (not aperture) ring from the T setting to the 1 second setting. Since the shutter speed ring is at the front of the lens (and NOT easily grasped), this is certain to introduce vibrations for short exposures. That is the reason it makes sense to cover the lens first.

On the GW series of cameras, the shutter speed and aperture rings are awkward to reach and turn - much more so than Mamiya RB, Hasselblad, or pretty much anything else.

jacaquarie · Jul 18, 2017

Many thanks, now I have better understanding of the operation of T for this camera.
The off the wall thought, how about the second shutter? The traditional large format shutter that slips over the front of the lens? This worked for photographers a century ago.

Thanks.

MattKing · Jul 18, 2017

I'd recommend a neutral density filter, and a black baseball cap (with the top hole taped over).
Put the cap on, release the shutter, pull the cap away for 8 seconds, replace the cap, close the shutter.
A more closely fitted black tube might be better.
As well as a film that offers reasonable reciprocity numbers for an 8 second exposure.
A red 25A filter would often be a good alternative for the ND filter (assuming black and white film of course).

John Koehrer · Jul 18, 2017

Another simple solution is to use T and put a card or even your hand over the lens
when the exposure's done.

No reason to worry about the # of fingers or thumbs available.

Is it possible to convert T to Bulb?

Moderator

Privacy & Transparency

Privacy & Transparency