X-Rite 334 Sensitometer

[adriazamel]

Hi,

I've got an X-Rite 334 Sensitometer, but I donﾒt know how to use for

photographic film application. The manual only explain for using in

x-ray films. I donﾒt understand the possible settings and your

better set for calibrating a photographic black&white film.

 

http://pers.blanquerna.edu/fotogrames/photonet_archivos/334_Sensitome

ter_Operation_Manual_en.pdf

 

Thanks.

Adria

[john_shriver]

<p>From reading the description, this is a device for <b>exposing</b> a step wedge on X-ray film. It has no measurment capabilites, but is designed to be paired with the model 381 <i>densitometer</i> to measure the densities.</p>

 

<p>Even if you are interested in using it for exposing conventional film, I'm not sure it would be much use for that. They don't say what the lumen-seconds are for each of the 8 exposure settings, which would be essential for any work calibrating film speeds. Also, the only choice of light colors are blue and green, where you want a neutral white. Plus, for zone system work, you want to make exposures through your lens and shutter.</p>

 

<p>The matching 381 densitometer may not be of much general purpose use, it may well be designed to automatically read the step wedge printed by the 334.</p>

[john_shriver]

<p>Well, I wound up getting an X-Rite 334 on eBay for a pittance. Worked, of course.<br>

Finally managed to use it on some TMAX 100. Using the default exposure setting of #3, it's really not putting out enough light for ISO 100 film. The first four steps are just film-base plus fog. Maximum density was 1.49. I figure that exposure setting #3 is probably about right for ISO 400 film, although even it may need a tick more. Perhaps setting #7 would be reasonable for ISO 100 film.<br>

With only 21 steps, at half-stop (0.15 log exposure), you only have 10 stops of range -- not much to spare.<br>

It's not going to be useful for really slow film, it just won't put out enough light to get a full HD curve.. I suppose at step #1 it might be useful for one of the super-speed films, but you may well lose the shadow region.<br>

So, it is useful if you want to compute the contrast index of your processing. But, since you don't know the absolute exposure, it's not a lot of use for computing film speed.</p>

[dennis_ng]

Wonder whether you can take a couple more exposure if it is just not enough light?