Kodak Calibrated #2 Step Tablet and Kodak 2x10" Calibrated Photographic Gray Scale

Hello

 

What diferent are between Kodak Calibrated #2 Step Tablet and Kodak

2x10" Calibrated Photographic Gray Scale?

 

is it the same product?

 

Thanks

Hi Carlos,

 

I don't know the difference between the two Kodak items--you

might want to email Kodak. Here is another supplier of such

items:

 

http://www.stouffer.net/Productlist.htm

Hi Carlos,

The calibrated #2 step tablet (I have the uncalibrated version)is used for exposing film and/or paper. It's like a piece of film with 21 steps of varying degrees of exposure on it. The 2x10" gray scale comes printed on paper which could be photographed to check proper exposure, development, etc. I've never used it. I prefer to use the #2 step tablet as I can use it for both film and paper. The uncalibrated version is cheaper. If you have a densitometre, you can then calibrate it yourself. Stouffer also makes them and are cheaper. They also make 31 step tablets for more accuracy, in a 4x5" size. Was any of this helpful?

 

Andrew

The Kodak #2 Step Tablet is a film with patches of different densities. It has densities from 0.05 to 3.05 in 21 steps of 0.15 density increments. From the density range and being on film, these must be transmission densities. It is available in two forms, calibrated and uncalibrated. "Calibrated" means that the specific step tablet has been measured on a densitometer and the actual densities of that particular tablet written down. For most purposes the uncalibrated tablet is suitable; if you want to calibrate a densitometer to high accuracy, you might want the calibrated tablet.

 

The 2x10" Photographic Gray Scale is a reflection density standard printed on B+W photographic paper. The scale has patches from nominal densities of 0 to 1.8 in 12 steps on 0.15 density changes. It too is available in calibrated and uncalibrated form.

 

The basic answer is that these products are not the same: one has transmission densities, the other reflection.

 

These products are listed in the "Kodak Professional Accessories" catalog which is available from Kodak's website, however, these items are now distributed by Tiffen, as explained in that catalog. The former paper catalogs from when Kodak directly distributed the product have more information.

 

I suppose that you have some book or manual that calls out these products by name. You should be able to substitute similar products, such as ones made by Stouffer. The list prices in the 1997 Kodak Professional Photographic Catalog are very high for the calibrated products, much higher than what Stouffer charges for similar products. The uncalibrated versions are significantly less. I don't know what the current prices are.

The URL for the catalog listing the Kodak products is at Tiffen's website because distribution is done by Tiffen: http://www.tiffen.com/Kodak%20Professional%20Accessories%20catalog.pdf

If I may ask, why do you need a calibrated step wedge? In about every case, I find that a non-calibrated step wedge meets my needs, so long as I know the actual densities. There's a large difference in price.

 

In a calibrated wedge, they go to the extra trouble of making the densities of each step a certain value. (e.g. Kodak calibrated step wedge.) In a non-calibrated wedge, the intervals between the densities on each step are approximate, but you are also sent their actual values to within about 0.015 density units, if not to within 0.01 density units. They read them on a good densitometer. I don't care about the actual densities, so long as they are approximately equally spaced. I do care that I accurately know the values of the density on each step, and they provide these with a non-calibrated step wedge. (Make sure you ask, I know that Stouffer will provide them.)

 

It depends on the application. As a statistician, I'm a stickler on technique and accuracy. But, I've never needed a calibrated step wedge.

I have to disagree with Neil about the difference between calibrated and uncalibrated step tablets, at least as supplied by Stouffer. I have both an uncalibrated and a calibrated transmission step tablet from Stouffer. The calibrated tablet (C-suffix in the part number) came with a handwritten listing of (what I assume to be) the actual measured densities. These measurements agree to typically 0.01 with my densitometer. The uncalibrated came with no measurements -- all you know is the nominal (or target) values. Stouffer has specs on how much the actual values can deviate from the target values (e.g., http://www.stouffer.net/T2115spec.htm) -- from 0.02 for low densities up to 0.10 for the high densities. On my calibrated tablet, the deviations between actual and target densities are non-zero but much better than allowed by the specs -- the maximum deviation is 0.03.

 

So, for Stouffer, the actual densities are not guaranteed to be on target, whether or not the tablet is calibrated or uncalibrated. And I think you only get the actual measured values if you pay extra for the calibrated tablet. I agree that for most purposes you don't need the actual measured values. On the other hand, unlike Kodak, Stouffer doesn't charge a huge increase in price for the calibrated version, so it might be worth getting to check the operation of a densitometer.

I have a very accurate late model McBeth densitometer if anyone needs any densities read.

 

Kevin