ND filters to slow down exposure - help

[Pere Casals]

Pere, excuse my confusion, please.
The OP wrote, in part,
[B]


And my mind went into 'what is reasonable' therefore presumed the unlikely success of a hand held one second exposure. I hope we are okay, Pere.

Best,
Jac

Oh, don't need to excuse... of course

Time ago I bought a cheap photocell type tester and I was very surprised that even my best shutter had remarkable differences from marked speeds, in fact a new shutter can have +/- 30% error and it is still under specs, so they can vary a full stop (1/40 to 1/80 for 1/60) even brand new. Mechanical shutters are not precise, fortunately they usually repeat same time, so a tester solves the thing.

I'm surprised about the fact that (in general) there is lot recommendations about modifiying film speed by say 1/2 stop while there are few warnings about checking shutters. I feel that in reality overexposing 1/2 stop is just a safety belt for the shutter variability. Overexposing negative film is not that bad, but one stop can ruin an slide... so Velvia likes shutter testers

[xkaes]

Let's take two giant steps back. I normally shoot ISO 100 speed film at around ISO 64. That means if the subject is in full sunlight -- a BIG if -- a correct exposure would be f16 @ 1/60. If I stop down to f32, the speed changes to 1/15. If I add on a Yellow filter, it becomes 1/8. If I add ND8 + ND4 + ND2 (6-stops), I'm down to 8 seconds. I also try to minimize the number of filters for a number of reasons, but there is PLENTY of flexibility here to get to 1 second or longer -- using 1, B, T, or even a lens cap! Throw in a little reciprocity failure and it's even more. And at these speeds, who needs a timer, other than ONE MISSISSIPPI?

[Bob Salomon]

Let's take two giant steps back. I normally shoot ISO 100 speed film at around ISO 64. That means if the subject is in full sunlight -- a big if -- a correct exposure would be f16 @ 1/60. If I stop down to f22, the speed changes to 1/15. If I add on a Yellow filter, it becomes 1/8. If I add ND8 + ND4 + ND2 (6-stops), I'm down to 8 seconds. I also try to minimize the number of filters for a number of reasons, but there is PLENTY of flexibility here to get to 1 second or longer -- using B, T, or even a lens cap!

If you are shooting atf16 at 1/60 and stop down to f22 you would be at 1/30.

[xkaes]

Got me there. I'll change it to f32. It's late in the day!

[Pere Casals]

Let's take two giant steps back. I normally shoot ISO 100 speed film at around ISO 64. That means if the subject is in full sunlight -- a big if -- a correct exposure would be f16 @ 1/60. If I stop down to f22, the speed changes to 1/15. If I add on a Yellow filter, it becomes 1/8. If I add ND8 + ND4 + ND2 (6-stops), I'm down to 8 seconds. I also try to minimize the number of filters for a number of reasons, but there is PLENTY of flexibility here to get to 1 second or longer -- using B, T, or even a lens cap! And at that speed, who needs a timer, other than ONE MISSISSIPPI?

If you stop down to f22 (from sunny 16), the speed changes to 1/30, not 1/15, so the thing ends in 4s with ISO 50 and a Yellow

And you can also add exposure compensation on bellows extension... Anyway if stacking 3 ND filters + Yellow better if they are of top quality, Hoya HD3 or the like, or using a ND32 or ND64, IMHO 4 stacked filters are a lot of filters.

[durr3]

I am going in circles here ....... I just want to shoot with this lens until I can get the shutter to be reliable. What do you guys suggest I try? I do not have to shoot at 1 sec. I just want to get a decent exposure. I will be shooting this coming Monday and will not have time to find other film.
It is not the end of the world....I have other lenses, but I wanted to try out this Verito.

[Pere Casals]

I am going in circles here ....... I just want to shoot with this lens until I can get the shutter to be reliable. What do you guys suggest I try? I do not have to shoot at 1 sec. I just want to get a decent exposure. I will be shooting this coming Monday and will not have time to find other film.
It is not the end of the world....I have other lenses, but I wanted to try out this Verito.

If you have a contrasty scene you may shot N-2, so shot it ISO 25 and develop less time (6 min 15s for Xtol Stock), stack ND filters (and perhaps yellow or better red) until you get at least 2s exposure.

You'll get great photographs...

Just have filters very clean, if you are to stack a lot. You also can buy a N32 or N64 when you can, these filters will be also useful to get smooth rivers and seas.

[durr3]

Thanks for all the help ...... now is the time for me to get out and give it a shot (pun intended)!
I will report the success or failures!

J

[Christopher Barrett]

BTW, you can get really heavy ND filters... they became all the rage a couple years ago. I use a Lee Big Stopper for my 4x10 color work along the Chicago lakeshore... it's 10 stops. Your sunny f/16 @ 1/60th would be like 17 seconds with that Filter, plus any reciprocity factor.

CB

[Jim Jones]

I've placed a sheet of evenly exposed and fully developed film in the holder in front of the raw film to reduce exposure for pinhole solar photography. This may be a handy trick this August. Experiment first.