4X5 Velvia exposure methods

[Ivan J. Eberle]

Extensive use of various density graduated neutral density filters is the traditional way of keeping landscape exposures within the latitude of Velvia 50. For transparency work, you need also to know precisely what speeds your shutter is providing-- most will not be dead on one or more of the indicated settings. Hopefully it will at least be consistent.

I'd been manually metering with 35mm color transparency film for two decades myself before making the jump to both large format, medium format and DSLRs in the past couple of years. I learned early on that bracketing is always the best plan in sketchy light, back in the days when I had a film-only workflow, though I find it less and less necessary these days since I'm shooting with Astia 100F, and first proofing with a DSLR.

Personally, I'm finding histograms/blown highlight warnings and the instant feed back of a DSLR with spot metering to be extremely useful. Too, Matrix Metering on my Nikons is nearly foolproof for not blowing whites, my Pentax 645N matrix a bit less so in high-contrast. Though I do have a D300, my D200 has a lower dynamic range, and an ISO 100 setting so it's a better fit with LF metering. Outdoors in either snow or low-key situations I first use the spot-meter to find a known good middle toned (18˚ gray) value as a starting point, and bracket around this until I'm happy with the histogram.

So far, I've had far more problems with sluggish LF shutters in cold weather than picking the right exposure using this method.

(I'm with KR here. You can buy a whole camera for what a lightmeter costs-- and if it has an X-sync terminal, use it to proof your flash output as well. With either, you'll still have to factor in bellows extension, reciprocity and filter factors though.)

[dsim]

Personally, I'm finding histograms/blown highlight warnings and the instant feed back of a DSLR with spot metering to be extremely useful. Too, Matrix Metering on my Nikons is nearly foolproof for not blowing whites, my Pentax 645N matrix a bit less so in high-contrast. Though I do have a D300, my D200 has a lower dynamic range, and an ISO 100 setting so it's a better fit with LF metering. Outdoors in either snow or low-key situations I first use the spot-meter to find a known good middle toned (18˚ gray) value as a starting point, and bracket around this until I'm happy with the histogram.

The in camera histogram of a DSLR is far from accurate. At the golden hours I've measured deviations by as much as a stop. The reason being is that the histogram is based on the white balance set in camera which is basically two multipliers used to equalize the sensitivity of red and blue channels to the green channel. In order to view an accurate histogram white balance should be disabled and a linear curve loaded in camera.

In my opinion a spot meter will produce better results.

[Richard M. Coda]

Color Zone system...

Get a spot meter
Get a MacBeth Color Checker Chart
Meter the middle gray patch in both sun and shade, mark down your EV readings.
In the SAME sun and shade (best to do all sun together, and then all shade together) then meter each patch and mark down your EV reading.
Calculate the difference between each patch and the middle gray patch (eg. +1/3, -2/3, etc.) and write each down.
When you're out in the field... if the main color you want is yellow, meter the yellow. Then look at your notes for yellow. It should be give-or-take +1 stop. Whatever your meter gave you for yellow in the field, give it one extra stop of exposure. Done. It is bullet-proof (within the limitations of the film).

[Ivan J. Eberle]

The in camera histogram of a DSLR is far from accurate. At the golden hours I've measured deviations by as much as a stop. The reason being is that the histogram is based on the white balance set in camera which is basically two multipliers used to equalize the sensitivity of red and blue channels to the green channel. In order to view an accurate histogram white balance should be disabled and a linear curve loaded in camera.

In my opinion a spot meter will produce better results.

Perhaps you've misunderstood me. I'm not using a DSLR on autopilot. I almost always manually dial in the exposure with an in-camera spot meter when the light or subject is tough. Coming from 30 years of shooting film it's become fast and intuitive and I trust it most when there's sufficient time. However, I also find that in fast-changing light, Matrix metering is quite excellent and can well be relied upon, with an understanding of what subjects and situations tend to fool it. (Matrix and spot are both metering options on my film-based Nikon F5 and Pentax 645N, incidentally.)

In using a DSLR to calculate my 4x5 exposures, a histogram is most helpful to graphically show the dynamic range of an image and the distribution (e.g. whether to use a GND filter) and the highlight clipping warning can be similarly useful. Though I wouldn't rely on either to try to tweak and correlate a film exposure directly, as film and sensors behave differently in the highlights. One can recover highlights somewhat with digital when "exposing to the right". No getting it back with transparency film.

A spot meter is a spot meter, they all measure an 18% gray reflectance (or else should be calibrated to do so). Used in manual mode I'll put my Nikon D200, D300 or P645N up against anything out there. My meters also happen to also take nice images, albeit admittedly at something of a weight penalty over a 4x5 and a spotmeter alone. But if you have a DSLR with an accurate spotmeter already, and tend to carry it with you even when shooting with a view camera, as I and apparently others do, a handheld meter seems rather superfluous.

(All that to say I'm rather pleased with my Velvia 50 exposures on 4x5 sheet film.)

[Doug Dolde]

When I shot tranny film I always metered the brightest spot, usually a white cloud then opened up 1.5 stops. Of course grads were also employed sometimes but with the same principle, just factoring in the grad.

[dsim]

Perhaps you've misunderstood me. I'm not using a DSLR on autopilot. I almost always manually dial in the exposure with an in-camera spot meter when the light or subject is tough.
Used in manual mode I'll put my Nikon D200, D300 or P645N up against anything out there.

Ivan I understood what you were saying and didn't mean to allude to you using a DSLR on autopilot. The fact remains that histograms are based on white balance which will affect an exposure decision especially in fleeting light. To have an accurate in camera histogram you need to load a UniWb with a linear curve.

A simple test demonstrates this fact. In manual mode, calculate exposure for a scene, WB 10,000k, shoot. Repeat test with WB 4000K. Don't change exposure. Even though the exposure doesn't change, the histograms will be radically different hence affecting exposure judgement. Failure to nail the white balance can impair one's assessment of the tonal range of a histogram.

A spot meter is a spot meter, they all measure an 18% gray reflectance

18% grey value actually comes from the print world. The ANSI standard calibration for light meters is a luminance value that is approximate to the reflectance of 12% gray. I've used meters calibrated to 13% but that's another thread.

Regards

[Jamie Bennett]

Thanks for all the advice, this is a really great site with lots of help. Many years ago I had a Hasselblad as "option 2" in my wedding bussiness and would shoot Velvia 50 through this when out doing landscapes. I would basicly take a incident light reading and bracket to get something decent. Using negative film is a good idea, NPS was my prefered film for shooting weddings and I love its good handling of high contrast subjects and smooth tonal range, I have been dreaming of a 4x5 Velvia trannie on my light box though! I think I will get a spot meter and educate myself on its use.
I am also looking forward to shooting some black and white and have been educating myself for a while now on understanding the Zone system. Have read AA's "The Negative" as well as Chris Johnson's "The practical zone system" which is a little easier to get my head around. Thanks again for all your help, Jamie.