Metering for Aero Ektar/Speed Graphic & ND Filter Help

[urnem57]

Hi - I need some help and suggestions on how to get consistent exposure readings. I am shooting cars with an Aero Ektar Lens on a Speed Graphic. Mostly b&w film. The whole point of the Aero Ektar is to use it wide open for the shallow depth of field. Stopping it down defeats the whole purpose, obviously. I am shooting outdoors in bright sun for the most part. I have some solid ND filters as well as a variable. Very often I need a fraction of a stop or less than the next full stop up or down to maintain the 2.5 aperture. The Speed Graphic is limited on shutter speeds as well - 125, 250, 500, 1000. I have tried holding the ND filter over the incident meter, but as I move it closer and further away the readings jump up & down by at least a stop (sometimes more) I have tried using a wide cardboard tube behind the filter and sticking the meter under it only to get another set of readings (often wildly different from just the filter) Any incident reading with 2.5 as the aperture gives ridiculously high shutter speeds, obviously. The variable ND does not have marked stops, it rotates freely. But I am able to dial it in to where either of the above methods gives me a usable shutter speed.
What am I missing here? Without knowing exactly how many stops I am working with, it’s hard to calculate the compensation for the ND.
Should I get a spot meter and try one/both of the above methods on the highlights and then shadows and then go with the average?
I am open to experimentation and I am bracketing like hell as well. But some of my exposures are way off.
Thanks!

[Dan Fromm]

Why meter through the filter? If you know the filter factor you can meter normally and then adjust shutter speed/aperture. If you don't know the filter factor, meter a subject with and without the filter held against a reflected light meter's cell. Same subject, same distance, same illumination. You can't prevent light from finding its way to an incident meter's dome.

If you need to adjust shutter speed by a fraction of a stop and are using negative film, set shutter speed to the closest speed to the one required and shoot away. The film's exposure latitude will let you get away with several stops exposure error.

[urnem57]

Dumb question, but I have an incident meter. Is that the same thing? Thanks.

[LabRat]

Establish a filter factor, find your new EI setting for your film speed, adjust your meter ISO for your new EI, and meter/shoot away...

Steve K

[urnem57]

Nice. How do I establish the filter factor when using a variable ND? The Tiffen ND only has dots for markings. I don’t understand that part. Thanks!

[Tin Can]

Do you know Sunny 16, most here do and can use it reliably

I shot 35mm outside for decades with no meter

Film used to come with Sunny 16 guide ON every box of 35mm film

https://medium.com/@efaja/the-ultimate-guide-to-the-sunny-16-rule-part-1-f8f524a785eb

Even if I have a meter I always guess first then use the meter to continuously train myself

[Dan Fromm]

Dumb question, but I have an incident meter. Is that the same thing? Thanks.
Incident meters measure light falling on the subject. Reflected light meters measure light reflected by the subject. What a reflected light meter measures depends on light falling on the subject and the subject's reflectivity. A reflected meter will see a large difference between, for example, a wall painted white and a sheet of black velvet. An incident meter won't.

[Dan Fromm]

Nice. How do I establish the filter factor when using a variable ND? The Tiffen ND only has dots for markings. I don’t understand that part. Thanks!

Read the manual. If you don't have the manual, ask Tiffen for help.

[urnem57]

That article is useful, thanks. But The Aero Ektar Lens needs to be used at 2.5 (wide open) It’s figuring out the process to maintain that aperture.

[Tin Can]

If 2.5 is YOUR ruie, not mine and I have the exact same setup, you could add light

The Speed was used mostly by Newspaper men and they often shot a powerful flash bulb with any shot, which helped make the exposure constant in any light, day or night

You have MADE your film exposures tough to do

Why?

[urnem57]

If 2.5 is YOUR ruie, not mine and I have the exact same setup, you could add light

The Speed was used mostly by Newspaper men and they often shot a powerful flash bulb with any shot, which helped make the exposure constant in any light, day or night

You have MADE your film exposures tough to do

Why?

I am after the VERY shallow DOF and the bokeh that The Aero Ektar produces wide open. It makes for some very cool exotic car detail images.

[Tin Can]

The question always is, how fast, how much money?

I'm out as I am old and slow!

[Corran]

Just use your normal ND filter with the appropriate filter factor? At full sun at f/2.5 with an ND4 filter on 100-speed film you'll be at roughly 1/1000.

You may not even need the ND filter. There's some light loss from the staining that afflicts many/most Aero Ektar lenses. I meter assuming it's about f/4 in actual light transmission and it works out. I have just done 1/1000 in sun and it's fine. You can test for this.

Don't overcomplicate it.

[Corran]

PS: full sun, on Efke 25, my 6" Aero-Ektar on a Speed Graphic, I think the exposure was 1/60 or 1/125 (I overexposed it and used a pyro developer):

https://1.bp.blogspot.com/-tDrFErOMj2g/YBhKXYOYOpI/AAAAAAAANY4/5EbS-soyO3IXqbVZFpT7gWrECxuHj3u8ACLcBGAsYHQ/s800/aewos.jpg

[urnem57]

Great photo! And yes, that is exactly the kind of thing that I am after. Thank you! I have experimented a bit with Rollei RPX 25, as well. It’s such a thin base that it’s on that it’s rather tricky to work with. Here’s the type of thing that I am after:
212083

[Tobias Key]

Personally would just compensate for a non variable ND filter by changing the ISO on the meter and leave it at that. If you are shooting black and white film you can probably live with over or underexposing by half a stop or so if you need to. Otherwise just set the lens to f2.8, I doubt you could tell the difference in a blind print viewing.

[urnem57]

Lots of great ideas. The members of this board are very helpful. Thanks!