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John Kasaian
11-Dec-2007, 09:42
Since remodeling my dark(er) room I'm finding that I need to change how I do some things, especially contact printing. I've always used a painter's light and in the room's former configuration I'd clamp the the light onto a towel rack. Since removation though, the towel rack has migrated to another, less convenient wall. I thought of clamping the light to a chair back, but the folding chairs we have are too low-backed to work comfortably with, so I was wondering, does anyone here use an enlarger for a light source for contact printing? Would it work (I can't see why it wouldn't unless I were to use a super slow paper like AZO) and are there any tricks or issues I need to be aware of when using an enlarger for contact printing?

Oren Grad
11-Dec-2007, 09:52
Yes, I use my 4x5 LPL with dichroic head as a light source for contact printing. It's great - the dial-in filtration is convenient for printing on variable contrast paper, it's easy to adjust the head for optimal coverage of different negative and paper sizes from very small to very large, and the aperture control on the enlarging lens and neutral density filter switch in the head, together with the enlarging timer, allow for very flexible exposure control.

John Kasaian
11-Dec-2007, 09:53
Thanks, Oren!

Oren Grad
11-Dec-2007, 10:07
The nice thing is that you don't need a big 4x5 enlarger to get these conveniences, since you're not trying to fit the negative in the head anyway. If you don't already have an enlarger, a smaller format dichroic enlarger should be just fine too, and at today's prices for used 35mm or medium format enlargers, it'll be great value for money.

David Karp
11-Dec-2007, 10:11
And no need to worry about alignment!

Mark Woods
11-Dec-2007, 10:26
I use my enlarger and have the metrics for different paper posted near it along with the height of the enlarger.

Brian Ellis
11-Dec-2007, 10:52
I think an enlarger is an excellent source for contact printing. Among other reasons, using VC paper becomes feasible (assuming, of course, that you don't use Azo or another graded paper). It's also easier to adjust the position of the light source than it is when you clamp a bulb to a chair or shelf or whatever.

Bruce Barlow
11-Dec-2007, 11:21
I use my old Beseler 45mx for Azo contact printing. Took out the lensboard, cranked it down most of the way. It works fine with a Zone VI Cold Light and stabilizer. Too powerful for other papers, so I use my LPL for those, with a lens in it.

rippo
11-Dec-2007, 11:29
i've done contact printing using a 6x7 color enlarger, for 8x10 negs (mostly 'digital' inkjet negs). i've also done some 11x14 paper interneg/positives. works well, and it's nice to have it all properly timed. pick up a color or dichro 6x7 enlarger on the cheap.

John Bowen
11-Dec-2007, 11:56
and are there any tricks or issues I need to be aware of when using an enlarger for contact printing?

John,

Nobody has mentioned this yet but, assuming you will be using a lens on your enlarger, be sure to put a negative in a carrier and focus the enlarger prior to exposing paper.

I use an enlarger to contact print all the time.

John

rippo
11-Dec-2007, 12:00
and then remove the negative.

but why does it need to be focused? and couldn't i just focus on the carrier's edge? i assume this is just for consistency and edge falloff, right?

(i don't do this enough to claim any expertise.)

Oren Grad
11-Dec-2007, 12:00
Nobody has mentioned this yet but, assuming you will be using a lens on your enlarger, be sure to put a negative in a carrier and focus the enlarger prior to exposing paper.

Why?

Pat Kearns
11-Dec-2007, 12:30
I contact print all of my negatives from 5x7 down to 35mm using my enlarger. As mentioned earlier, VC filters can be used with VC paper. I always have the lens in use which gives me the ability to control the light via f/stops and/or height adjustment. I've never used a negative holder because it produces a rectangle rather than a circle of light. I'm scratching my head as to why you need to focus and what's the point if there isn't a negative in the carrier?:confused:

Geert
11-Dec-2007, 13:04
John,

Nobody has mentioned this yet but, assuming you will be using a lens on your enlarger, be sure to put a negative in a carrier and focus the enlarger prior to exposing paper.

I use an enlarger to contact print all the time.

John

John,

you are incorrect in your statement to focus the enlarger.

On the contrary, you should unfocus it when using it as a light source for contact printing. It all has to do with dust.

Greetings,
G

John Bowen
11-Dec-2007, 15:22
MY Contact Printing Routine

Equipment:

Zone VI Cold Light Head, Zone VI Stabilizer, Contact Printing Frame, Graded Paper.

I set the enlarger at a consistent, predetermined height. I focus the Lens using a scrap negative, I then remove the negative and negative carrier. I focus the lens in order to provide consistent light. My proofing exposure is predetermined and repeatable. I BELIEVE the exposure would vary if the bellows extension for the enlarging lens varried from zero to 12" (the approximate amount of bellows on my Beseler 45 MX enlarger). After all, isn't that why we factor bellows extension into our LF exposures???

To be honest, I've NEVER done a contact print with a lens without first focusing the lens. The ONLY time I ever have trouble with dust is if the dust is on the contact printing frame glass. But again, I use a cold light, not a condenser so as they say.....

YMMV

Greetings,

J

rippo
11-Dec-2007, 15:44
i actually run the head up as high as it will go, then raise the lens so minimum extension. it's repeatable AND out of focus. basically, jam everything up high, open up the lens, and i'll always get the same light output and max coverage.

Vaughn
11-Dec-2007, 17:08
John, is there any particular reason to use a lens/lensboard? I suppose one should check to see if the pool of light is even. Without a lens the only variable for light intensity would be enlarger height -- bellows and fstop factors are eliminated.

If one is using a condenser enlarger and a lens, no matter where one sets the focus, one would have to be careful not to accidently focus on any dust speck that may be on any of the condenser surfaces (not limited to the plane the negative is usually on.)

Vaughn

John Bowen
11-Dec-2007, 17:38
Vaughn,

I contact print under two different sets of circumstances....Proper Proof and LF/ULF Azo prints.

For Azo, I don't use a lens. I do however have a "Cold One" Azo cold light source. I raise he enlarger to a specified height (19" on my Beseler 45MX) and remove the lens and lensboard. The bellows is at minimum extension. My exposures are typically 9 seconds with TMY Pyrocat HD negatives. My times using Bruce Barlow's method with a Zone VI cold light are 60-120 seconds...way too long for my tastes. Bruce gets times around 36 seconds for Tri-X HC-110 negatives

For proper proofing 35mm or 4x5 negatives, I follow Fred Picker's Zone VI Workshop (page 38, third printing) "Put any negative in the enlarger, set up for about an 11x14 print and FOCUS (emphasis added). Mark the enlarger column with tape or magic marker and a corresponding spot on the moveable head so that you can find this exact elevation in the future. Remove the negative and replace the empty negative carrier. Position the proofer (contact printing frame) in the center of the light cast on the countertop or easel. Stop down the leas to f/8. Turn the enlarger off and set the timer for three seconds......."

HOWEVER, Ansel in "The Print" (copyright 1983) page 68 states "You must be sure that the enlarger gives uniform illumination over the area of the printing paper. With an empty negative carrier in place, raise the enlarger until the projected rectangle of light generously covers the area where the paper will be, with several inches to spare on all sides. At full aperature, set the lens focus forward (emphasis Ansel's) from the position that produces sharp enges on the negative carrier, this is important because it ensures that the "image" of the enlarger's diffusing screen or dust on the condenser, will not be projected on the paper causing uneven lighting or mottle, especially when the lens is stopped down."

I couldn't imagine using a lens for Azo prints...the exposures would likely be in hours. Similarly, I couldn't imagine doing proper proofs on other papers without a lens ...the exposures would likely be way too fast.

I guess the most important issue is to be consistent in your methods YMMV

Vaughn
11-Dec-2007, 18:55
Sounds reasonable, John,

So from what I understand, the purpose of focusing a negative first would be just to standardize the bellows extention. With the other enlarger positions marked (and a stable/constant light source) one would get the same amount of illumination each time. There would be no other optical benefit.

AA's suggestion would not be needed in a perfect Picker paradise where dust is totally banned from the darkroom.;)

Vaughn

John Bowen
11-Dec-2007, 19:20
Vaughn,

Agreed.

John

Mark Sawyer
11-Dec-2007, 19:25
I use an enlarger with the lens and lensboard removed, and insert any vc filters where the negative carrier would go. If I need to reduce the light, I use a lensboard with no lens. The bellows is completely compressed and the enlarger head is run up to its highest point.

Brian Ellis
11-Dec-2007, 22:43
John,

Nobody has mentioned this yet but, assuming you will be using a lens on your enlarger, be sure to put a negative in a carrier and focus the enlarger prior to exposing paper.

I use an enlarger to contact print all the time.

John

Perhaps there's something I'm missing here but why would you use a lens when the enlarger is only being used as a light source? But if you did why would you also put a negative in the carrier? And if you used a lens and put a negative in the carrier why would you focus the lens? Wouldn't that procedure just result in projecting the negative in the carrier onto the negative and paper that's being contact printed and mess up the contact print? Or am I missing something here?

Vaughn
12-Dec-2007, 00:08
Perhaps there's something I'm missing here ...?

Hello Brian,

This is what you are missing...

1)The purpose of focusing a negative (after locking the enlarger at a predetermined height) is to have the lens at the exact same height each time one makes contact prints. This is to insure that the amount of light hitting the baseboard is the same every time at the same f/stop.

2)After focusing the negative and neg carrier are removed and are no longer in the lightpath.

3)A lens is used to reduce the amount of light when printing on relatively fast enlarging paper.

Since I print in a university darkroom, I have never worried about such consistancy/precision (difficult to achieve in a community darkroom). I just set the enlarger up at whatever height seems right, throw the lens out of focus and make a test strip.

Vaughn

Brian Ellis
12-Dec-2007, 10:22
Hello Brian,

This is what you are missing...

1)The purpose of focusing a negative (after locking the enlarger at a predetermined height) is to have the lens at the exact same height each time one makes contact prints. This is to insure that the amount of light hitting the baseboard is the same every time at the same f/stop.

2)After focusing the negative and neg carrier are removed and are no longer in the lightpath.

3)A lens is used to reduce the amount of light when printing on relatively fast enlarging paper.

Since I print in a university darkroom, I have never worried about such consistancy/precision (difficult to achieve in a community darkroom). I just set the enlarger up at whatever height seems right, throw the lens out of focus and make a test strip.

Vaughn


Thanks, explaining that the carrier and negative are removed before the contact print is made clears things up. My enlarger (a Beseler MXT) had a scale along the side where the head travelled so using this technique to get the same height every time wasn't necessary and I just kept the bellows fully compressed, which made it unnecessary to worry about focusing.