Quality of Light

[Pawlowski6132]

So, I contated printed some MF negatives a few weeks back. I used an incadescent bulb. The same setup I use for my 8x10 contact prints.

I picked the negative I like but, couldln't enlarge it to the quality I saw in the proof. I just coldn't get the same balance of sky/clouds and skin tone.

I have a Beseler CB7 with the Beseler dichro head. I haven't changed the bulb since I got it so, I'm not sure what's in there but, it's definitely not a cold light.

Is this a red herring?

[Vaughn]

I vote for the ruddy fish...

Very different inherent quality of light between contact printing and enlarging...no matter what type of enlarger one is using.

[Ken Lee]

I'm not sure what's in there but, it's definitely not a cold light.

Try a cold light :)

[cowanw]

The paper will choose the wavelengths it uses to expose; as long as there is white light, there is blue and green.
You will need to change grades as you enlarge.
Splot printing is always an option.

[Pawlowski6132]

The paper will choose the wavelengths it uses to expose; as long as there is white light, there is blue and green.
You will need to change grades as you enlarge.
Splot printing is always an option.

I used the same paper for the contact print and the enlargement. Only difference was the light source. My confusion is there seemed to be such a disparity in the print. The proof showed a nice image. The enlargement was basically garbage.

[Jim Noel]

Every time you pass light through glass, it is altered. This is magnified when light passes through a lens. An enlargement will never exactly match a contact print. An expert printer may come close, but they will not be exact matches.

[Vaughn]

I used the same paper for the contact print and the enlargement. Only difference was the light source. My confusion is there seemed to be such a disparity in the print. The proof showed a nice image. The enlargement was basically garbage.

A good hint of the problem can be seen in the very nature of the various types of enlargers. Condenser enlargers are suppose to produce prints that are sharper and contrastier than diffusion enlargers, etc. All enlarging systems alter the quality of light. I suggest you do not contact print your negatives...then you will not know how much better contacts can be! LOL!

Buy a bigger camera...;)

Or you may need to fine-tune your choice of film, exposure and development to get what you want when enlarging. Is not that a fine thought...good luck!

[joselsgil]

Since you have the Dichronic head, you may need to adjust the color settings on the head, if you are printing with variable contrast paper. If you are using VC paper, you may want to try split contrast printing or switch to a different grade of paper.

The second item that can cause your enlargements to be inferior, would be the quality of the enlarging lens.

Third item, make sure your chemistry is mixed properly and not exhausted.

The Beseler dichronic head is definitely not a cold light. If you have the older, early '70's blue CB7 with the dichronic head, you should have a cooling system hooked up to the head. You could not miss the cooling setup as it has a large hose going from the fan box to the head. The later dichronic 45S head is much more compact without the external cooling fan. IIRC, the dichronic head, use a halogen bulb with a mixing chamber to match the negative size. I haven't opened the head on my CB7 dichronic head either. :cool:

Jose

[ROL]

I don't get it. I'm going to take a different tack here (non exposing light). You mean a contact looks better than an enlargement?!? I'm pretty sure that may be one reason why some people who have the choice prefer contact printing. I frequently note the differences you apparently refer to, particularly in 120. Without stating the obvious physics of each, enlarging is a different animal than contacting, each having it's own strengths and weaknesses.

If what you're referring to is the apparent beauty of a small compressed image, by way of example I am way, way too often suckered into the apparent beauty of a thumbnail image on a web page, only to be disappointed by the clickable enlarged version, mostly devoid of interesting composition, be it in subject or tone.

Then again, maybe it is the "Quality of Light", but perhaps not the enlarging light.


My 1.999999999999999999999999999999999999999999999999999999999999999999999 ¢.

Chew on it. Spit it out. Just not at me. ;)

[Brian Ellis]

How big are you trying to make the print? And what size medium format negative? In general there isn't much of a difference in my experience between a contact print and a well-made enlargement up to about 4x. I sometimes think, perhaps unfairly, that people who claim that contact prints blow the socks off enlargements just don't know how to make a really good enlarged print. It's pretty easy to make an excellent contact print from a good negative. It's harder to make an excellent enlargement.

[jp]

I think that enlarger head has two lamps in it. The lamps get dim over time. The dicro mirrors get dirty. That affects quantity of light, but little else. You should keep a spare lamp; that'll tell you what you need to re-order.

You may need to clean the lens to increase contrast; make sure it's not hazy. You may need some extra contrast. Maybe the film carrier slot is leaking light into the darkroom and fogging paper during exposure? Lotsa possibilities. Maybe your developer went weak over the few weeks since you did the contact prints?

[Paul Hoyt]

I would be willing to bet your enlargement has more contrast than your contact print. In a contact print, all the light that passes through the negative strikes the print; none is lost. When you enlarge, some of the light exiting the negative is bent by silver grains and fails to strike the print. This happens at the higher densities of the negative and with less light exposing the enlargement at the higher densities, the contrast is increased. If you match the clouds in the enlargement to the clouds in the contact print, the lower densities will have received more exposure than the contact print and are much lower in tone. You will need to decrease the contrast of your enlargement to get closer to the contract print. Different light sources (condenser, diffusion, point source) are not equal and will require different changes in contrast for enlargements. I have needed to make changes in contrast when making enlargements from an 8X10 enlargement to a 16X20 enlargement.