Nikon 50mm f4.0 vs. 50mm f2.8

depend on the film, processing, quality of the camera and enlarger and lens.
Tri-X I think does best for small prints but then I usually don't over 8x10
anyway. Anyway some people like grainy blurry photographs.

Sheldon Strauss
www.shel.focalfix.com

O.K. I got it. "The hall of mirror" idea took to me to back to high school
physics days.... I also have a Schneider 80mm WA lens which I can use for
35mm enlargement. The problem is that I can't raise my enlarger to it
maximum hight due to a low ceiling in my darkroom. Anyway, thank you all for
all your help..
Regards
Shawn..

"David Nebenzahl" wrote in message
...
On 2/25/2004 9:48 AM Mike spake thus:

O.K. I can hear the sighs from here, but how do I align an Omega DII
enlarger? Is a glass carrier required as well in 35mm format?

Glass carrier isn't necessary for 35mm IMHO. If you enlarger isn't
aligned perfectly, just stop down to f11 or higher.

The DII has 4 sets of rollers on which the head slides on. There is a
bar
connecting each set, and this bar has a hole in the center. By
loosening
the screws, and sticking a screwdriver in the hole, you can change the
alignment. Do your best...with just the negative carrier you should get
a
perfect rectangle (not a trapezoid)

So you can use the extremely simple and extremely accurate alignment
method I
used for my Beseler 23C. I adapted the method given by Conrad Hoffman
(http://members.rpa.net/~choffman/beseler01.htm), which uses two mirrors
to
set the negative stage and baseboard plane-parallel to each other.
Basically,
you cut one large piece of mirror and put it on the baseboard. The other
piece
is cut in a narrow strip that gets clamped in the negative carrier. This
piece
extends out the side of the enlarger and has a hole in it through which
you
can view the other mirror. (My modification to his method was to simply
scratch the reflective coating of the mirror off in a small spot, rather
than
going to the trouble of drilling a hole in the mirror. Worked fine.)

You shine a light up at the upper mirror and view through the hole. The
idea
is to make the "hall of mirrors" effect--multiple receding
reflections--collapse to a single reflection (in both X and Y axes), at
which
point you can be sure that both mirrors, and therfore the enlarger parts,
are
in perfect alignment. Forget the Zigalign and its vaunted 0.00000000005"
alignment claims.


--
It's fun to demonize the neo-cons and rejoice in their discomfiture, but
don't make the mistake of thinking US foreign policy was set by Norman
Podhoretz or William Kristol. They're the clowns capering about in front
of
the donkey and the elephant. The donkey says the UN should clean up after
them, and the elephant now says the donkey may have a point. Somebody has
come out with a dustpan and broom.

- Alexander Cockburn, _CounterPunch_
(http://www.counterpunch.org), 9/17/03

On Fri, 27 Feb 2004 20:04:31 -0500, "Sheldon Strauss"
wrote:

Anyway some people like grainy blurry photographs.

Sometimes it works. My favorite such image I photographed a
couple walking along the Atlantic City surf holding hands using a
Soligor 80~180 /3.8 zoom with two cheap 2X converters on it. Film was
Kodak Gold 1600 which I exposed with the lens wide open. Perhaps a
little over-exposed but then that film was very low in saturation
anyway.


Regards,

John S. Douglas, Photographer - http://www.darkroompro.com
Please remove the "_" when replying via email

"Shawn H"

The shape of the projected image must be the same as the negative
being projected AND the image must be in focus at all points.
The only equipment needed is a ruler and a square and an easel will
do for the square.
The proof of a good alignment is the projected image. Am I making
myself clear? Dan

On 2/28/2004 2:29 PM Dan Quinn spake thus:

"Shawn H"

The shape of the projected image must be the same as the negative
being projected AND the image must be in focus at all points.
The only equipment needed is a ruler and a square and an easel will
do for the square.
The proof of a good alignment is the projected image. Am I making
myself clear? Dan

That method will work; however, I think the two-mirrors method is even more
accurate, as it can detect extremely minute angular shifts from parallel. But
certainly the is-the-image-square? method is a lot better than nothing.


--
It's fun to demonize the neo-cons and rejoice in their discomfiture, but
don't make the mistake of thinking US foreign policy was set by Norman
Podhoretz or William Kristol. They're the clowns capering about in front of
the donkey and the elephant. The donkey says the UN should clean up after
them, and the elephant now says the donkey may have a point. Somebody has
come out with a dustpan and broom.

- Alexander Cockburn, _CounterPunch_
(http://www.counterpunch.org), 9/17/03

David Nebenzahl wrote

Dan Quinn spake
The shape of the projected image must be the same as the negative
being projected AND the image must be in focus at all points.
The only equipment needed is a ruler and a square and an easel will
do for the square.
The proof of a good alignment is the projected image. Am I making
myself clear?

That method will work; however, I think the two-mirrors method is
even more accurate, as it can detect extremely minute angular shifts
from parallel. But certainly the is-the-image-square? method is a lot
better than nothing.

Personally I would'nt trust to a method other than one using a
negative in the negative carrier or the carrier itself, and an image
projected upon the paper holder in it's usuall position. My objection
to other methods stems from an awarness of mechanical imperfection.
Also, there's the simple matter of "more things that can go wrong".
My instincts are for fewer moveing parts. But there again
I'm the minimulist.
I was only trying to make clear that a good alignment can be done
without purchasing anything. Further more, nothing need be fabricated.
I favor a No buy No build approach to wadeing into this and other
endeavors. I think that approach should be at least mentioned,
and more often, where it does apply.
For example, when the subject is ventilation how often do you see
someone suggest "do without". Case in point: I've an air leaky darkroom
and use oderless, fumeless chemistry. That said, I and some others
don't need a ventilation system. An in room HEPA air filter
will do me. Dan

John,
I can't give you an NBS traceable test result on your diffraction
question, but I can tell you what happens with my old f/4 50mm El
Nikkor. Running the enlarger up to 12x and watching the grain with a
10x grain focuser, as the aperture gets down to f/8, the grain is still
visually sharp. Somewhere between f/8 and f/11 it begins to get soft,
and at f/16 it is mush. And that was in the print center.

As for glass carriers -- in an enlargement to 11x14, the depth of field
at the negative is just a couple of tenths of a millimeter. (A sheet of
typing paper is roughly a tenth of a millimeter thick.) Hold a
glassless negative carrier up to the room light so that the light is
glancing off the back of the negative. You will be able to see the warp
in the negative. Glass carriers are needed for enlarging 35mm negatives
beyond 8x10.

Bob

p.s. Spammers should get the hell out of my e-mail.
-----------------------
John wrote:

On Wed, 25 Feb 2004 11:48:40 -0600, Mike
wrote:



Glass carrier isn't necessary for 35mm IMHO. If you enlarger isn't
aligned perfectly, just stop down to f11 or higher.



I wonder what the diffraction limit is on a 50mm enlarging
lens ?


Regards,

John S. Douglas, Photographer - http://www.darkroompro.com
Please remove the "_" when replying via email

Get POPFile - free and darned efficient!

Jorge

HypoBob wrote in news:40464188.6030503
@pacbellhell.net:

p.s. Spammers should get the hell out of my e-mail.
-----------------------

On 3/3/2004 12:35 PM HypoBob spake thus:

As for glass carriers -- in an enlargement to 11x14, the depth of field
at the negative is just a couple of tenths of a millimeter.

Small correction: you mean depth of focus, not depth of field. Similar but
different animals. (Depth of field is on the subject side of the lens, in this
case the print.)


--
The Bush administration should restrain itself from its imperial arrogance
that has so alienated countries around the world. Their contempt for the
United Nations in the dash to war with Iraq; their support of the coup in
Venezuela in April 2002, and the continuing hostility toward President
Chavez; the pressure on nations of the world to exempt the US from the
International Criminal Court, now joined by their contemptuous attitude
toward President Aristide must be halted. It is time for the people of the
USA to make this point clear even if the administration continues to walk
around with wax in its collective ears, with eyes closed, and ranting about
its version of the world as defined by Bush.

- Excerpt from TransAfrica statement on the situation in Haiti, 2/17/04
(http://www.transafricaforum.org/)

David,

When enlarging, the negative is the subject and the focus limits around it are in the depth of
field. The print acts like the film and is in the focal plane of the lens, so the terminology
down there is the depth of focus. It sounded a little strange to me too, but I saw that
nomenclature in a few references, one of which is on page 292 of Ralph Lambrecht's book "Way
Beyond Monochrome". It is quite a good book, by the way; one of the few really good new photo
books I have come across lately. Ralph used to contribute to this ng, but I haven't seen him on
it lately.

I am in complete agreement with the sentiments in your signature block, but I fear that The
Little Moron has a huge supply of money and dirty tricks that will carry the day. I hope you
live in a swing state where your vote will count for something. I live in California where our
votes don't count, but TLM's energy buddies love our $2.25 a gallon gasoline.

Bob
------------------------
David Nebenzahl wrote:
On 3/3/2004 12:35 PM HypoBob spake thus:

As for glass carriers -- in an enlargement to 11x14, the depth of
field at the negative is just a couple of tenths of a millimeter.


Small correction: you mean depth of focus, not depth of field. Similar
but different animals. (Depth of field is on the subject side of the
lens, in this case the print.)