Use of cheap digital to act as both meter and viewscope

[Dave Saunders]

Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

[Greg Lockrey]

Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

You make them by cutting out a 4x5 rectangle (or whatever format equivalent you will be using) from a piece of 8x10 cardboard or any stiff material. Mine is black on one side and white on the other. Until you get used to the focal length of your shooting lens, it's a good idea to add a string of a given length to match the focal length of your lens to be placed at your chin to aid in setting up your focal distance to match your camera. Basically you just look though it to determine your composition. Once you've shot thousands of images, you will know what your camera field of view before you have it set up.

[Bob McCarthy]

I tried this a year or so ago. My recommendation is "forget it"

With color, film has a much shorter Dynamic Range. And many, if not most, digital camera meters are biased to protect highlight burnout. If you just want to meter a grey card, it will work fine, otherwise it will confuse you and waste film. The new digitals have 8+ stops of DR. Film has maybe 5.

With B&W, the match up is closer on DR, but the digital thinks in terms of protecting highlights, shadows be damned. Backwards from the needs of B&W negative.

Keep your spot meter. Though I would have no problem transfering meter data from an F5 for Velvia. Any digital camera meter/histogram is biased for the conditions of that technology.

bob

[Vaughn]

Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

If you want the viewing card to be smaller, that's fine -- as long as the proportions are correct for your format. (the smaller the card, the closer it must be to your eye to mimic the view of the same focal length lens.)

I also find closing one eye helps to eliminate the influence of our ability to see in 3D. Compositions can be thrown off the fact that foreground objects seem to be seperated from the background due to the their appearence in 3D -- that separation may not transfer to the 2D of the print...objects that are defined by their position may not be so well defined by light.

Vaughn

[rippo]

I shot away, and got some decent photos, but when I showed my wife shots by Jack Dykinga and David Muench (I'm a color landscape fan), she kept saying "How come everything is so much clearer and sharper than your pictures?" I explained to her that they used large format cameras and she said "Maybe you should get one of those?"

I would weep tears of joy if my wife ever said that to me!

[Matus Kalisky]

I did and do use a digital SLR as a lightmeter. It is very convenient to have a preview of the picture that you will othervise see in a week or two. For me this works but the preview on the LCD screen somehow takes the thinking a bit out of the way. Sure I do use the spot meterering feature to check the range, but in my experience what fits in the range of the digital sensor (Minolta 7D) that also fits on the film. I am not aware that my camera would give me 8+ stops of dynamc range.

The bottom line is - it works, it is relatively fast, but a DSLR is heavy and it is too easy to get a correct exposition without spot metering and findig the brightest and lightest part if the scene - so it has a tendency (at least in my case)to take the thinking away - and your intuition and experice does not grow as it possibly could without it ..

[Bob McCarthy]

http://www.dpreview.com/reviews/nikond300/page20.asp

Our new Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from (the cameras) black to clipped white (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).


Sensitivity Shadow range Highlight range Usable range
ISO 100* -5.2 EV 3.3 EV 8.5 EV
ISO 200 -4.7 EV 4.1 EV 8.8 EV
ISO 400 -5.1 EV 4.1 EV 9.2 EV
ISO 800 -5.1 EV 4.1 EV 9.2 EV
ISO 1600 -4.3 EV 4.1 EV 8.4 EV
ISO 3200 -4.0 EV 4.0 EV 8.0 EV
ISO 6400* -3.7 EV 3.9 EV 7.6 EV


* Non-standard sensitivities

Dynamic Range compared

All of the current crop of 'advanced amateur / semi-professional' digital SLRs (D300, A700, 40D and E-3) deliver around nine stops of dynamic range. The biggest difference is in the balance of the range, the D300 and A700 both deliver around four stops of highlight range (above middle gray) where as the 40D around three and a half and the E-3 around three. Both the 40D and E-3 deliver more shadow range.

Camera
Shadow range
Highlight range
Usable range
Nikon D300 (ISO 200) -4.7 EV 4.1 EV 8.8 EV
Sony DSLR-A700 (ISO 200) -4.9 EV 3.9 EV 8.8 EV
Canon EOS 40D (ISO 100) -5.7 EV 3.4 EV 9.1 EV
Olympus E-3 (ISO 100) -5.7 EV 3.0 EV 8.8 EV
Nikon D200 (ISO 100) -5.0 EV 3.2 EV 8.2 EV

[joolsb]

The new digitals have 8+ stops of DR.

I would be very surprised if digitals actually had a usable DR that big. It all depends on careful conversion of the raw file how much DR you actually get.

One consideration of using the histogram that nobody seems to have mentioned is that the difference between film response and sensor response. I would be very wary of relying on histogram data when deciding on an exposure for film.

Film has maybe 5.

This depends on the film. At the low end is Velvia with only around 4.5 stops. Colour neg will give around 7 and B&W film around 10. I always carry some colour neg sheets in addition to my preferred Velvia as it's a life-saver when you need extra DR and grads are out of the question.

I do carry a digital compact when shooting with my LF kit but I only use it to try out alternative shots before setting up the heavy artillery. I wouldn't dream of using it as an exposure meter and if I need to check out a composition in 5x4 format, I use the tried-and-tested framing-card approach outlined above.

[Joseph O'Neil]

For metering I have found, at least in B&W, my Pentax spot meter works best. For colour, my hand held Seconic works best.

However I always drag a digital with me. Sometimes I shoot a scene first with digital to see what it looks like, and sometimes I see something I want to shoot but it isn't worth a sheet of film.

joe

[Bob McCarthy]

I would be very surprised if digitals actually had a usable DR that big. It all depends on careful conversion of the raw file how much DR you actually get.

One consideration of using the histogram that nobody seems to have mentioned is that the difference between film response and sensor response. I would be very wary of relying on histogram data when deciding on an exposure for film.



This depends on the film. At the low end is Velvia with only around 4.5 stops. Colour neg will give around 7 and B&W film around 10. I always carry some colour neg sheets in addition to my preferred Velvia as it's a life-saver when you need extra DR and grads are out of the question.

I do carry a digital compact when shooting with my LF kit but I only use it to try out alternative shots before setting up the heavy artillery. I wouldn't dream of using it as an exposure meter and if I need to check out a composition in 5x4 format, I use the tried-and-tested framing-card approach outlined above.

I have found the DR numbers to reflect my actual experience. The raw converters create very similar dynamic range output, Color, noise, blown highlight recovery, sharpness do vary somewhat between converters. Lord knows i've tested them all looking for the magic program, it doesn't exist.

As to color film, I was referring to transparency. I guess this is my bias.

And to the histogram comment. Correct sir, and the reason I was displeased with trying to use a digital camera as a meter. The histogram, doesn't match up with any film I use when predicting shadows or highlights. A calibrated histogram to a film would be the bomb, but it doesn't exist, certainly not within any digital camera I've used. In a roundabout way I thought this is what I was describing in the previous posts, I can see I was too obtuse...

No display on the back of any of my digital camera is large enough to substitute for a ground glass. But, some of the compacts do have largish displays and are possibly useful, I will conceed.

Bob