Condensor Vs Diffusion

Condenser Vs Diffusion

I just finished my twice a year enlarger calibration: summer is a low printing time for me.

I'm pleased to say my Focomats are happy and ready to start printing again.

Out of curiosity, I put a kodak step wedge in the negative carriers, and used a baseboard densitometer to compare the two enlargers. Even after 30 years with one, and 20 years with the other, it's good to ask questions.

The first, a Leitz Focomat Ic, has a condensor head. The second, a Leitz V35, has a diffusion head. If anything, the lens in the V35 is a bit contrastier than the on in the Ic.

The step that read .75 in the diffusion enlarger, read .90 in the condenser.
The step that read 1.05 in the V35 read 1.35 in the Ic.

The attached .jpg shows the ( simplified ) results.

Basically, if a negative prints Zone V in the diffusion head enlarger, it prints Zone VI with the condenser. And if diffusion prints Zone VII, the condensor renders it at Zone IX.

The condenser enlarger, in effect, sees a given density as less transparent than does the diffusion enlarger. Therefore, the condenser will print it lighter in tonality.

To print on a conderser enlarger, you therefore must develop the film less than you would for a diffusion enlarger. OR, use a different paper, or contrast paper.

I'm glad I have both enlargers, and I've always used them to complement each other. It's interesting to see, however, the numbers. I think it would be safe to say the differences between condensor and diffusion on these two enlargers would be indicative of the difference in general.

Hoping this trivia is interesting to some Apugger !

I'm always interested. I only have a diffusion enlarger running (but a condensor 5x7" mamouth in rebuild). Just curious, but did the condensor ALSO print the shadows darker? That would be the logic for me, as they are supposed to be contrastier, no? I'm my overly simplified understanding that would mean printing zones V-IX higher and II-IV lower?

Or am I again demonstrating my utter lack of a grasp on things?

NikoSperi said:

I'm always interested. I only have a diffusion enlarger running (but a condensor 5x7" mamouth in rebuild). Just curious, but did the condensor ALSO print the shadows darker? That would be the logic for me, as they are supposed to be contrastier, no? I'm my overly simplified understanding that would mean printing zones V-IX higher and II-IV lower?

Or am I again demonstrating my utter lack of a grasp on things?

Click to expand...

In comparing the two, if the highlight values are held to the same Dmin then the Dmax would be greater.

slightly off the sensitometry side , I use both diffusion and condensor in my printing room. I find I go to the condensor for prints that I want to sparkle, zip, burn you eyeballs with sharpness , but if I am doing portraits or images that I need a very smooth , syrupy , make you want to cry softness I will use the diffusion.
Both light sources are very good and its a dynamite combination to have in a darkroom.

Donald Miller said:

In comparing the two, if the highlight values are held to the same Dmin then the Dmax would be greater.

Click to expand...

I'll take that as a "yes"... :confused:... I think... maybe.

NIKO: good questions. I've added a chart to the first post to show how the two enlarger heads differ.

Beginning with a trasparent negative, each step of density is seen as more opaque by the condenser enlarger, and so will print it lighter. The effect is proportional to the density.

Said differently ( So I can be confusing in different ways ! ) if you begin with pure black ( film base ), each step of exposure added will make a lighter image. Add any amount of exposure, and the condenser will make a lighter image than the diffuser.

And to make a 'perfect' negative to print for a condenser enlarger, you just develop the film less.

DON: Yep

BOB: Right on !

Usually you need 1/3 to 1/2 grade difference to match prints from the !C to V35. Mine were purchased new and this has not changed.

Normal difference is 1 grade.

I think the difference is because the IC is slightly less contrasty than a double condenser, Omega D2 and Phillips PCS130, and The V35 is slightly more contrasty than than my other diffusion machines specially the Chromega all using the same lenses.

For the sake of clarity, I must add TO THE ORIGINAL POST that a direct densitometer reading of the step wedge proved identical to the readings projected by the V35. The condenser enlarger added .03 density units to each Zone.

There is no attempt here to start a new ideology, just to share (trivial) data.

I use an early Ic, with the second version Focotar(not the focotar-2), and no filter tray. I've been thinking really hard about buying a V35. The Ic is great, but 16x20's are a hassle, and lack of a filter drawer is a small hassle. I'm trying to decide between a late, grey head, white board Ic, or a V35.

My question is if there is a significant esthetic differance between prints made from these two enlargers? Most of my work is relatively grainy, and I like a nice crisp rendition.

outofoptions said:

Kodak tells you in their sheets that you should shorten developing time if you use a condenser enlarger as it will add contrast.

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didn't kodak put this in the film data sheets ?
i remember reading something like " for cold light or diffusion enlarger heads, process film with 1/3 more time "

maybe ( probably ) i am wrong ...

-john

There are various condenser enlargers and they can vary in the light they produce. The Leitz Focomats and the Leitz Valoy that I've used have a pretty diffuse light compared to other enlargers I've used. My current LPL enlarger has a much "harder" light than the Valoy I was using previously.

I presume this has something to do with the light source. The Leitz enlargers have big round heads and they use a large frosted bulb. Light is reflected around inside the head and softened before it is focused by the condensers. With the LPL, the bulb is smaller and it is reflected by a mirror into the condensers which makes for a harder, more focused light. Negatives have more contrast when printed with the LPL compared to the Leitz.

I love the quality of light from Leitz enlargers. Unfortunately, I don't have room for two enlargers in my darkroom and the LPL is a good compromise.

jnanian said:

didn't kodak put this in the film data sheets ?
i remember reading something like " for cold light or diffusion enlarger heads, process film with 1/3 more time "

maybe ( probably ) i am wrong ...

-john

Click to expand...

You are not wrong. times are for a condencer enlarger. It will give you a contrast index of .45 average. For diffused you want a CI of about.6

Could be the condition of the enlarger lens you use when you see the difference in the light quality whether it's hard or not hard.

I thought and still think the outcome of a LPL condenser enlarger (7700 type) is very similar to the quality of an Omega D2 if you couple a Nikor lens. That's the reason why I bought my Fuji(LPL OEM) condenser head. I've used a Leica enlarger before, but it gave definitely a different experience than an Omega.