Condenser enlargers: Kodak

http://www.kodak.com/global/en/professional/support/techPubs/j86/j86.jhtml

"The development times in the following tables are starting-point
recommendations. They are intended to produce a contrast index of 0.60
for T-MAX 400 Film and 0.56 for the other films. These development
times should produce negatives with a contrast suitable for printing
with a diffusion enlarger. To adjust contrast for printing with a
condenser enlarger, reduce the development time by 20 to 30 percent."

If you're using a condenser enlarger, reduce your times!



Why?

http://www.fineartphotosupply.com/coldlightheads.htm

 

Of course, I know this. This is for the benefit of ***others***.

 

the contrast index for condenser enlargers for N development should be
about 0.43.

Wim

 

Why isn't this equivalent to saying, "Do an N-1 development." ?

-Peter De Smidt

 

Isn't that exactly what the zone system claims for 35mm?

Nick

 

Cannot imagine thats correct for a number of reasons. Typically if you expose a
grey card and process it N you will get a .75 density (which is also the reflection
density of the card if you use a densitometer which has a reflection sensor) this is two/three stops below the maximum
printable density that can be held without dodging on a diffusion light source on a normal grade 2 paper
or using a grade 2 Kodak filter and obtaining seperation in your shadows and mid tones.
Kodak use to say a 1.0 density was Normal for grey card exposures and condensor enlargers,
if the CI is .43 and you have a BF+ at .10 that means from the bottom
where you get shadow detail to the hightlight density you
have two stops .15 apart. hardly enough density even for a diffusion enlarger
to make normal seperation of highlight mid tones & shadows.

 

Maybe you use grade three paper because your negatives are drastically underexposed?
Now if you used the Zone system and understood what a contrast filter is for
you might be able to make prints on Grade 2 or polycontrast paper.....thats
a lot less stress for for someone like you that has a loose grasp on reality.
I don't follow people like you, I avoid them on the street when I can.

 

The problem is you called it CI, CI is not average gradient.

 

You CANNOT use the Zone Sytem in 35mm work. It's designed for sheet
film!

I used Varigam and Varilour before you were born!


You don't know what you're talking about. In 35mm work, grade 3 is
normal, not grade 2!

 

You CANNOT use the Zone Sytem in 35mm work. It's designed for sheet
film!

I used Varigam and Varilour before you were born!


You don't know what you're talking about. In 35mm work, grade 3 is
normal, not grade 2!

See:
http://216.239.51.104/search?q=cach...ta.pdf+bill+troop+grade+3+film&hl=en&ie=UTF-8


Here is a quote:
"If there is any secret to obtaining high sharpness and fine grain, it
is to
ensure that the negative has a low density range. Maximum density
should
not exceed 0.9 above base+fog for small negatives, or about 1.2 for
larger
negatives. This means that 35mm negatives of normal scenic contrast
should
ideally be developed to print well on grade 3 paper. Medium and large
format negatives should be developed to a slightly higher contrast, to
print on grade 2 paper."

 

I don't doubt that that 35mm negatives may print better on grade three,
adjusting contrast in the negative can allow you to print on many grades,
maybe grade three is normal for 35mm, I am willing to accept that
for this discussion. I apologize in part as I was baiting you towards defining why you
hold these convictions, however I can not say I have appreciated your tone of voice
throughout your posts. I have therefore addressed you in what I have deemed a likewise manner.

I would say though that using a no filter setting and printing a negative whether
on condensor or Dichroic will produce an optimal print on the paper grade
that produces it, which is not to say that it is the manufacture's
or an otherwise commonly accepted norm. Being that one can adjust the whole roll of film,
the zone system if one wants to expend the effort to shoot three seperate cameras can be used
on 35mm photography, thats not to say doing so allows for intuitive shooting when
action, facial expression and spontienity are primary considerations.

It can be done.

 

I understand many people use variable-contrst paper without any
filter, which in the case of Kodak materials gives about grade 1 1/2.
This is not a good situation, as it leads to making overly-contrasty
negatives. I have actually heard students say 'I don't need a filter'
as if the filter were some kind of crutch. Use the filters! I used
Ilfobrom paper a lot in the past, and I used more of grade 3 than of
anything else. I hardly ever use VC papers.

 

Most manufacturers standardize the Multigraded papers to print
at grade 2 with "No Filter", but the the test criteria for showing this
is rather involved, to write out here. Part of the reason Grade three
works better for you is that you are enlarging the prints. Sensitometrically,
enlarging works differently than the contact printing procedures common used
to determine paper HD curve data. There is a difference between a projected
image and a contacted one, both in appearance and sensitometric readings
of the printed image.

In otherwords if I raise the enlarger to where it spills a set amount of light
(to cover an 8x10 enlargement) if I then contact print the negative or
step wedge using the same Filter (whatever I decide it to be) there will
be a decide difference in a print that was project verses the contact.
All other criteria being the same, development, process time, agitation.
The only variable is that one print was contacted verses being projected.

 

I understand many people use variable-contrst paper without any

Actually the grade can differ depending of the type of enlarger head,
lamp and lamp age etc. In some situations it might be 1 1/2 and in other
set-ups it might be 2 1/2. Using a filter will not prevent this
variation from happening but will minimize it.

Severi S.

 

Its always been my understanding the filter helps stabilize the exposure
somewhat.

 

I know that in the past Polycontrast was closer to 1 1/2, by Kodak's
info.

No, grade 3 is recommended for 35mm for other reasons. It's to keep
the desnity and contrast (and thus graininess) DOWN, allowing for best
possible definition, in conjunction with condenser enlarging.

No, it's an optical phenomenon.

Especially with condenser enlargers.

I'm glad you know this too.

 

So are you telling us that using VC paper is a crutch?

David "reality is a crutch for those who can't handle drugs" Neb

--
We are receiving alerts about a worm that is spreading around the Internet
contained in a .zip archive file. What is surprising to security analysts
is that this worm is spreading at all since it cannot execute without user
intervention. Security analysts believe the rapid spread indicates that
recipients are still opening email attachments even after they have been
warned many times that it is unsafe to do so.

- Description of the "Sobig.E" worm, ca. June 2003

 

By the way, graded papers are generally superior to VC papers.
Mid-tone gradation is superior.

 

message

You don't really need to. The negatives will print on
about one grade softer paper but will be identical in tonal
rendition. I may be more convenient to adjust the negative
contrast to the enlarger illumination but since absolutely
identical results can be had with either diffusion or
condenser enlargers by adjusting paper grade there is really
no other reason to do it.
The effect is due to scattering of light by the silver
particles in the emulsion. Thick, coarse grain, films have
more difference than thin emulsion, fine grain films. Color
films show virtually no change in contrast with different
amounts of diffusion because the dye particles do not
scatter light.
The difference in apparent density with diffuse compared
to specular light is called the Callier Effect and is
sometimes called the Callier "Q" factor. It becomes
important where accurate sensitometric measurements are
desired but is not a critical parameter in practical
photography, other than its good to know it exists.

 

Its too bad too because graded papers are on deaths door
at least in the USA. I started printing using Graded paper
and really learned to love Forte Bromofort grade 3 in 16x20.