Are Shutter speeds continuously variable?

[RedLion]

I've got a Welta Weltur 6x9, and I've ordered a gossen light meter (which has a mechanical dial for looking up the speed-to-aperture setting). Just yesterday, I noticed that the light meter has the speeds marked off as 1/60, 1/125, 1/250, etc... in standard fashion.

However, I see on my Welta's speed setting ring on the F4.5 Compur-Rapid lens, that the speeds are marked off as 1/10, 1/25, 1/50, 1/100, 1/200, 1/400.

So I'm wondering how this is going to work? Are the shutter speeds on the Welta continuously variable? So, for example, do I just tweak the wheel on my Compur-rapid shutter a bit to get an estimated 1/125 of a second so as to match up with my meter?

Thanks!

Joe

 

[chris00nj]

Just use the closest setting. With negative film there shouldn't be any issue at all. Negative film has enough exposure latitude. I always err on the side of overexposure with negative film anyway.

It's not like the 1/125 setting will be 1/125 exactly.

If you are really concerned, you can make a slight adjustment to the aperture to compensate.

 

[elmer3.5]

Hi, yeah, don´t worry about that issue, i experienced the same for more than ayear with a Lieca II-f and the VC meter II, never was a problem.
Bye.

 

[Ronald M]

My M3 has the old speeds. Tweek the aperture 1/3 stop or put some marks on the meter dial where 1/10 is just faster than 1/8, 1/50 is a bit slower than 1/60. 1/100 is a little slower than 1/125.

 

[Ezzie]

Same problem here with my Gossen Sixton and my Kowa MF and DIY LF cameras. The former using the 10/25/50/100/200/500 regime, whereas the cameras have the more normal regime. If you are really worried then adjust half a stop aperture. However, I would suspect that the inaccuracy in the light meter and shutters make this exercise futile, you´ll need to shoot a few films and gain experience of what works and what not.

EDIT: Take notes

 

[VictorM.]

"Compur shutters can be set at intermediate speeds, but not between 1/10 and 1/25 nor between 1/300 and 1/500."

Quoted from the "Rolleiflex in Practical Use", 1952. Also found in "Rolleiflex Working Instructions", 1935.

 

[Gumby]

Please don't contradict internet "wisdom" with real data/information. 😉

 

[nikon_sam]

Better to adjust the aperture to the shutter speed...I have a Weston Master II meter and it shows a lot of the older shutter speeds...what I see missing is 1/125 but it does have 1/130...this meter breaks things down in 1/3's

Here's how it breaks down the shutter speeds...
1, 4/5, 2/3, 1/2, 2/5, 1/3, 1/4, 1/5, 1/6, 1/8, 1/10, 1/12, 1/15, 1/20, 1/25, 1/30, 1/40, 1/50, 1/60, 1/80, 1/100, 1/130, 1/150, 1/200, 1/250, 1/300, 1/400, 1/500, 1/600, 1/800, 1/1000, 1/2000

Here's the apertures...
32, 29, 25, 22, 20, 18, 16, 14, 12, 11, 10, 9, 8, 7, 6.3, 5.6, 5, 4.5, 4, 3.5, 3.2, 2.8, 2.5, 2.2, 2, 1.8, 1.5

So there you go...

It actually goes up from 1 sec. to 100 sec. but I didn't think those numbers were needed...

 

[hanskerensky]

Besides the fact that most leafshutters have no intermediate settings (they have speedcams with mechanical steps) it's allways a good thing to make one or more testfilms. At each shutterspeed make 3 photos, one with the diaphragma setting your meter shows, one underexposed by 1 stop and one overexposed by 1 stop. Most ideal is positive film as you immediatly see the difference. Compare the resulting developed frames and see if you have to correct the result of the lightmeter at any given speed.

Most of these shutters are old and some maybe serviced before resulting in a deviation of the original speed as shown on the Speed dial.

 

[sevo]

"Compur shutters can be set at intermediate speeds, but not between 1/10 and 1/25 nor between 1/300 and 1/500."

That depends on whether they have a ramping or stepped speed cam. Most rim set Compurs are stepped, but a ramping cam was an option on OEM Compur shutters. Hwever ramping cams were intended for cameras that had some other mechanism at their side which took care of accurate speed selection (e.g. detents).

I.e. you don't need to worry. On a shutter with a click-less rim set wheel, a single degree off already translates to more than a third stop error - if you happen have such a step-less shutter, the inherent time selection inaccuracy will be bigger than the differences between old and new time scale. And on stepped shutters you'll have to live with whatever times they offer.

 

[JPD]

"Compur shutters can be set at intermediate speeds, but not between 1/10 and 1/25 nor between 1/300 and 1/500."

...and not between 1/100 and 1/300 if 1/300 is the fastest speed.

That depends on whether they have a ramping or stepped speed cam. Most rim set Compurs are stepped, but a ramping cam was an option on OEM Compur shutters.

Didn't the stepped speed cam evolve at the same time as the EVS-system in the 1950's? The Weltur is from the 30's with the older Compur / Compur-Rapid.

 

[Roger Hicks]

Does anyone really believe that the marked speeds are going to be accurate anyway? They're almost certainly slow, e.g. 1/300 = 1/200, 1/100 = 1/60, 1/50 = 1/40, etc. In other words, the next HIGHER speed on the shutter has a fair chance of being witin 1/6 stop: meter 1/250, set 1/300, meter 1/30, set 1/50. A tolerance of 1/6 stop is closer than many leaf shutters delivered when new.

If you're shooting transparency (and I wouldn't with an old Welta), you may need to take account of this. If you're shooting neg, a bit of extra exposure will give you better tonality anyway.

Cheers,

R.