ND filters to slow down exposure - help

[durr3]

I want to shoot 4x5 Delta 100 film, with a Wollensak Verito 9 inch f4 lens. The "regular" shutter is erratic so I want to hand expose the shot.
I have three ND filters: a 2X, a 4X and an 8X. Will I be able to slow down Delta 100 to 1 sec or so? Assuming the light cooperates.

Thanks

[David Lobato]

Won't work for 1 second, you will need an 11 stop reduction assuming full daylight at f4 and ISO 100. Your three ND filters total 6 stops, 1+2+3.

[Jac@stafford.net]

I have three ND filters: a 2X, a 4X and an 8X. Will I be able to slow down Delta 100 to 1 sec or so? Assuming the light cooperates.

ND 8 lowers transmission by 3 stops. In a bright situation presuming f/16 is nominal 1/125th of a second, to achieve 1 second you will need at least an ND32 which is 5 stops, or to be safe an ND64, 6 stops. (I would not stack filters.)

[durr3]

What if I stopped the lens down to f6?

[Jac@stafford.net]

What if I stopped the lens down to f6?

No way.

[durr3]

Ha....ok THANKS Guys

[Pere Casals]

I want to shoot 4x5 Delta 100 film, with a Wollensak Verito 9 inch f4 lens. The "regular" shutter is erratic so I want to hand expose the shot.
I have three ND filters: a 2X, a 4X and an 8X. Will I be able to slow down Delta 100 to 1 sec or so? Assuming the light cooperates.

Thanks

I'd suggest to use a Shutter Tester to measure true shutter speeds, even true speeds are far from marked ones it is possible you have a couple of speeds that repeat exposure interval very closely. If you know what are the effective speed you can make perfect exposures without ND the nuisance.

There are shutters testers for $70 (CAM-LITE), there is also one that has a cost of $15 (ebay), this is a bare photocell you can plug to a PC sound card, then you use a free audio app (audacity) to record the signal and see how much time shutter allowed light to reach the photocell.

This is a good practice because mechanical shutters are not as precise as electronic ones, and it is important to know how owned shutters perform.

You also can place a a DSLR (without the DSLR lens) in the back of the view camera, then take and exposure with the Verito shutter, then leave the Verito shutter open and take exposures with the DSLR shutter to find the DSLR speed that is matching the image taken with the verito Shutter, so you'll know the effective speed of the verito shutter.

http://www.kenrockwell.com/tech/exposure-large-format.htm

[Jac@stafford.net]

I'd suggest to use a Shutter Tester to measure true shutter speeds, even true speeds are far from marked ones

The original poster wishes to make exposures of about one second, and in practice probably longer. What good is a shutter tester for such long exposures? If his shutter is so messed-up that 1 second is unreliable, he can revert to B or if his shutter has it, then T.
.

[Pere Casals]

The original poster wishes to make exposures of about one second, and in practice probably longer. What good is a shutter tester for such long exposures? If his shutter is so messed-up that 1 second is unreliable, he can revert to B or if his shutter has it, then T.
.

Hello Jac,

OP says he wants to make long exposures by hand because the Verito shutter is erratic. I suggest knowing true speeds (with a shutter tester) to get right exposures instead going to long hand exposures.

Regards.

[Jac@stafford.net]

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


I want to hand expose the shot. I have three ND filters: a 2X, a 4X and an 8X. Will I be able to slow down Delta 100 to 1 sec or so?

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

[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

http://christopherbarrett.net/wp-content/uploads/2015/03/LakeShore_001.jpg

[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.

[Bob Salomon]

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.

And, at small apertures you are into diffraction. That plus the questionable quality of many ND filters does not get you the best results.

[Bob Salomon]

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.

Send it out for service. Or replace the shutter.

[xkaes]

Talk about beating a dead horse. The guy can EASILY get to a slow shutter speed (assuming that is what he wants) using the film he has with a couple of the filters he already has -- and without having the stand on his head and spit nickels. I know that, and you know that. Now he knows it, as well.

[Pere Casals]

And, at small apertures you are into diffraction. That plus the questionable quality of many ND filters does not get you the best results.

Yes... stacking bad filters is not always a good idea, it may deliver same effect than an uncoated lens, I gess.

There is another sound solution: using my ISO 0.5 DIY emulsion :)

[Jac@stafford.net]

Talk about beating a dead horse. The guy can EASILY get to a slow shutter speed (assuming that is what he wants) using the film he has with a couple of the filters he already has -- and without having the stand on his head and spit nickels. I know that, and you know that. Now he knows it, as well.

Stacking filters is, in my experience, a bad idea.

And to the the subject of diffraction brought up by Bob S. at physically small apertures I call bullsh*t. For our large formats we have no worries up to F/22 for reasonable, ordinary enlargements.
.

[Pere Casals]

Stacking filters is, in my experience, a bad idea.

And to the the subject of diffraction brought up by Bob S. at physically small apertures I call bullsh*t. For our large formats we have no worries up to F/22 for reasonable, ordinary enlargements.
.

At /22 good, modern 4x5 lenses are diffraction limited. If this is important or not... this will depend on what one wants, and if it's better or not to stop beyond /22 because DOF vs sharpness is a technical matter. Bullsh*t is manure, so not a photography term.

[LabRat]

A still unsolved problem for me is when using heavy ND filters, that stray strong internal reflections could happen at some camera/light angles, (that were not light leaks, lens well shaded) somehow light bouncing in the optics or camera... You might see this if a bright light (like the sunset, very bright lights/reflections/beach sunshine/desert) on or slightly off lens axis... Usually a broad flare covering much of the neg...

Stacking filters is out for heavy ND's...

Steve K

[xkaes]

Stacking filters is out for heavy ND's...

Steve K

Funny, I've never had a problem using a 3.0ND (NOT 0.3ND) -- 10 f-stops -- in addition to a UV, plus a Polarizer, plus a Yellow or Orange, etc. I guess I'm just lucky.

[Pere Casals]

Funny, I've never had a problem using a 3.0ND (NOT 0.3ND) -- 10 f-stops -- in addition to a UV, plus a Polarizer, plus a Yellow or Orange, etc. I guess I'm just lucky.

Stacking filters has a variable effect, it depends on:

> Fiter quality, Hoya HD3 have less troubles than inferior Hoyas.

> Scene, sun in the framming is not the same than a subject in the shadow.

> Focal, sun in the scene delivers more relative parasite light with a long focal than with a wide.

> Clean filters vs not perfectly clean ones.


A polarizer in the stack is very good if sun is in the framming. As direct sunlight comes strongly polarized the Pol will remove a big share of it, reducing parasite light to a fraction. I guess placing the pol in the outer side of the stack may be the best, as direct sunlight is reduced from the begining of the bouncing chain.