Re: Re:Stouffer wedge (was VDB is "Brownprint" process?)

Thanks, Sandy- I'll look up the early Post Factory Magazine for the wedge.
I think I need the uncalibrated step wedge.
Susan
----- Original Message -----
From: "Sandy King" <sanking@CLEMSON.EDU>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Thursday, February 23, 2006 12:45 PM
Subject: Re:Stouffer wedge (was VDB is "Brownprint" process?)

>
> Susan,
>
> One of the early issues of Post Factory Photography had an excellent
> article, by Judy herself as best I recall, on the use of a step wedge
> in alternative printing. You should try to get a copy of the article
> as it really is great as a practical application of sensitometry.
> Someone mentioned this article not long ago but you may have missed
> it.
>
> You can actually buy calibrated T2115 step wedges from Stouffer for
> about $20 or so, but unless you are doing a lot of film testing and
> need a lot of precision the calibrated steps are a waste of your
> money. The steps do vary a bit, even from the same batch. I recently
> bought four more of the T2115 step wedges and they are all slightly
> different at Step 21, ranging from a low of 3.06 to a high of 3.09.
>
> Calibration just means that someone with a calibrated densitometer
> has read each of the 21 or 31 steps and you get that information.
>
> Sandy
>
>
> >>At 05:16 AM 2/23/06 -0800, Susan Huber wrote:
> >>
> >>>BTW; does one need a 21 step wedge for alternative processes and
> >>>how does one use it?
> >>>I went into the store yesterday and found out the Kodak step wedge
> >>>costs $144. US and the Stouffer wedge costs $5.80 US- a big
> >>>difference in price, any difference in quality?
> >
> >Kodak has (or had) a less expensive step tablet, about $18 in the
> >US. The $144 tablet, whatever it costs in the US, is probaably
> >*calibrated.* That is, minor variations in actual density, either
> >from batch to batch or even from strip to strip, occur in the
> >making. My understanding is that "calibrated" step tablets have
> >actual density of each step read & recorded.
> >
> >AFAIK this matters in rocket science (possibly).
> >
> >J.
>
Received on Fri Feb 24 07:22:47 2006