If you believe you can, or you believe you can't... you're right.
If you want to do a speed test and later development test.
Do it or you'll always question your results. Could it have been better(?) or not?
What works for some ain't the same for others.
David Vestal in "The Craft of Photography" uses a ring around method and the "Ansel Adams Guide" Volume 2 uses a test target method. They both work!
The Adams book runs from $20 and Vestal's from less than a buck on Amazon.
Vestals book is one of the easiest to read photo books around. Plain & simple English.
For a target something in a middle tone(gray) lets you compare hi, low and mid from a set of exposures.
"Is the featureless target for the film speed test light, dark, white? I've read it a hundred times and can't seem to get my simple mind around it."
In theory it shouldn't matter. Regardless of the target, the meter should tell you what combinations of shutter speeds and apertures at a particular film speed will produce a Zone V exposure. You pick one with the film speed at the manufacturer's rated speed and then reduce the exposure by four stops to make a Zone I exposure. Then do the same thing at different film speeds. But even though in theory it shouldn't matter, I never thought it was a good idea to use a black or white target, I sometimes used a gray card and sometimes used a sheet of smooth cardboard like from a cardboard box (with no writing on it of course).
Since shutter speeds are not always spot on from one speed to another it's a good idea to make your first exposure (the one at the film manufacturer's rated speed) at a combination of aperture and shutter speed such that the subsequent Zone I exposures (the ones at different film speeds) will be made by changing only the aperture, leaving the shutter speed the same throughout the series of exposures.
It's also a good idea IMHO to make some dry runs without film so you can get a good idea of what you'll be doing for each exposure, especially if you're doing the tests outdoors. The light needs to remain the same throughout the series of exposures. If the light changes after the first exposure your tests are no good and you have to start over. So you should move through the different exposures pretty quickly.
Someone mentioned the testing that The View Camera Store will do for you. I've suggested using that service myself many times, it's an excellent service at a reasonable cost and provides you with more information than you'll gain by doing the tests yourself. But I do think it's a good idea to do the testing yourself at least once just as a learning experience if nothing else.
Doing a film speed test isn't complicated, time-consuming (as long as the light doesn't change on you), or difficult to do. And at this point of your large format experience I think you'll learn more and get more useful information by doing a controlled test of this nature than you would by just going out and making a bunch of random photographs of different scenes, then looking at the negatives.
Brian Ellis
Before you criticize someone, walk a mile in their shoes. That way when you do criticize them you'll be
a mile away and you'll have their shoes.
Would an x-rite 890 do what is required?
You probably know the answer to this, but the light reflected from your test target is dependent upon the light falling on it, in addition to its ability to reflect light (looks white or looks black etc.)
What I do is to use a target that yields a zone I exposure with similar camera settings to the usual type of photography that I undertake.
For example, with ISO 400 film, using a target with EV in the 10 range.
Not sure but from the looks of it compared to the 810 I would say no.
Although not as good as a densitometer, you could use some color analyzers as a densitometer. For example the Jobo Colorline 5000 has a densitometer mode. As I recall, you use the enlager as a light source, place the film over the analyzer's sensor, and get a density reading. I did that for awhile. Worked OK but my curves were a bit suspect because some readings seemed off the mark.
Sharing a densitometer could work too. Maybe there is someone near you who will rent you one or just read the negatives for you.
I just read through the instruction manual... If you already own one and want to try to make it work, great! It includes both reflection and transmission densitometer inside a single, compact unit.
But because it is automatic, it may be finicky. You will need to find a test target that it can read. Or you may need to program it. I once spent a day with either one of these or similar unit trying to get past a strip read error, even when it was part of a system that made a test strip that it was programmed to read. I think the feed roller was skewing the sample as it ran it through.
Okay Gents, thanks for the info. I do not have one but there are plenty on ebay for silly cheap money so thought if it will do the job an easy way out.
take pictures first, make lists of equipment later.
Bookmarks