Densitometer, why do I need one?

Hi all,

I was wondering if you have a Reflection/Transmission densitometer and what exactly do you use it for in your process of hybrid photography?

I've read some people use a UV transmission densitometer to determine neg(printer transparency) density when they use it to contact print?

The reason I ask is that there are a few in the shop, second hand and I was wondering if it was worth the purchase. Mainly if it would help me make my prints and negs better? At the moment I get imagesetter negs and havent gone down the route of buying a home printer. I'm just doing silver contact printing and gum prints for the time being. Would like to get into Cyanotypes and Pt/Pd later...

For example, I'm stumped on how I would correlate data using a densitometer, when I read from reflection density of a print and then use that information to gather a curve? I know it would be much easier to use a scanner to scan the print, then figure out the values in Photoshop to generate a curve.

Cheers
Jacek
www.jagnight.com

I have a reflection densitometer. I use it to make sure that I can match the density on the screen with the density on the actual print. My goal is to match (within a per cent or two) the photoshop percentage (as measured by the eye dropper tool) and the final print. The curves are then adjusted to make sure the two match.

I don't worry about the density of the digital negative.

You only need this tool when you are calibrating your process, or when you make any change in your work flow.

They are not necessary, but they sure do make life easier and quicker.

Jacek, for gum a reflection densitometer isn't necessary, in fact it would probably only confuse you, since "density" or print tonality in the gum print is a function of pigment and pigment concentration. I'm using one at the moment, but only to make some points about tonality in gum for my website. It wasn't necessary as part of the calibration process, and I'm using a borrowed one rather than spending money on it.

Katharine