BigSteveG
Well-known
I've been going through the Aristo website and have read that negs o be printed through a cold light head should be developed 20-30% longer. Is this true? If so, why? Anyone w/ experience here?
Bryce
Well-known
Cold light heads are usually if not always diffusion type rather than condenser type heads. For some reason, having light from the source diffused before getting to the negative reduces the apparent contrast printed on the paper somewhat.
So the recommendation to increase developing time is to make up for this, assuming 'normal' developing times are for condenser type enlargers.
In reality you'll get the best results by trying various developing routines and narrowing down what works best empirically.
Have fun!
So the recommendation to increase developing time is to make up for this, assuming 'normal' developing times are for condenser type enlargers.
In reality you'll get the best results by trying various developing routines and narrowing down what works best empirically.
Have fun!
Trius
Waiting on Maitani
20-30% longer compared to what ... that is the question. Condenser heads collimate the light so that the rays are pretty much perpendicular to the negative
.......|
......( ) <----- light bulb
\condenser/
..| | | | | |
..| | | | | | <--- light
..| | | | | |
.\/\/\/\/\/\/
/condenser\
======== <--- negative
A cold light is a diffuse light source, where the light rays come from all directions. Whereas the light from a condenser source are more easily blocked by dense areas in the neg, light in a diffusion/cold light head enters the neg from multiple angles and it is the result is more penetration and highlight detail is enhanced.
For me, diffusion/cold light is the normal/standard source; it produces "lovelier" prints for the type of work I do. A well-known photographer (who m I won't name because it always seems to raise controversy
) described condenser-made prints as "chalk and soot"; i.e., not much detail in highlights or shadows. That was an exaggeration, of course, but he made his point.
I have seen many really nice prints made from a condenser head enlarger, and have made some myself. But I prefer cold light for the look it can produce.
Thus, for me and my way of working, I would reduce development of negs intended for condensor printing by whatever percentage I determined necessary through testing.
Earl, putting flame suit on.
.......|
......( ) <----- light bulb
\condenser/
..| | | | | |
..| | | | | | <--- light
..| | | | | |
.\/\/\/\/\/\/
/condenser\
======== <--- negative
A cold light is a diffuse light source, where the light rays come from all directions. Whereas the light from a condenser source are more easily blocked by dense areas in the neg, light in a diffusion/cold light head enters the neg from multiple angles and it is the result is more penetration and highlight detail is enhanced.
For me, diffusion/cold light is the normal/standard source; it produces "lovelier" prints for the type of work I do. A well-known photographer (who m I won't name because it always seems to raise controversy
) described condenser-made prints as "chalk and soot"; i.e., not much detail in highlights or shadows. That was an exaggeration, of course, but he made his point.I have seen many really nice prints made from a condenser head enlarger, and have made some myself. But I prefer cold light for the look it can produce.
Thus, for me and my way of working, I would reduce development of negs intended for condensor printing by whatever percentage I determined necessary through testing.
Earl, putting flame suit on.
Bryce
Well-known
Trius-
Whether for good reasons or not, the condenser type head seems to have remained the "standard" for B+W printing right to the end.
I cut my teeth on a diffusion head, later switched to a condenser (needed a bigger enlarger was the real reason) and decided I prefer the condenser. My prints are less lovely and tonal, but also more sharp and locally contrasty now.
On P-shop the equivalent would be maybe whether you prefer slightly more or less unsharp mask. Just personal preference, and also depends on subject matter. So I've ground a piece of glass to go in my filter drawer and guess what? My enlarger now works as either type on demand!
Whether for good reasons or not, the condenser type head seems to have remained the "standard" for B+W printing right to the end.
I cut my teeth on a diffusion head, later switched to a condenser (needed a bigger enlarger was the real reason) and decided I prefer the condenser. My prints are less lovely and tonal, but also more sharp and locally contrasty now.
On P-shop the equivalent would be maybe whether you prefer slightly more or less unsharp mask. Just personal preference, and also depends on subject matter. So I've ground a piece of glass to go in my filter drawer and guess what? My enlarger now works as either type on demand!
Trius
Waiting on Maitani
Bryce: I agree, though I never noticed much difference in real sharpness. Most of my printing with cold light has been with 4x5 enlarged to 8x10 or 11x, so sharpness was there anyway. That said, my 35mm prints with diffusion head are generally just as sharp as condenser; apparently sharper enlargements with condenser might actually be contrast differences. I'd have to do careful testing at matching tonal range to really tell.
One thing I've never tried is printing with a point source enlarger. Now that would be a challenge! Negs need to be absolutely pristine.
One thing I've never tried is printing with a point source enlarger. Now that would be a challenge! Negs need to be absolutely pristine.
FrankS
Registered User
I know a photographer who has a cold light head with 2 tubes of different colour. One tube determines the density of blacks and shadows, while the other controls highlight detail. Exposure time for each tube is controlled independently. With this setup, it's difficult not to make a good print from almost any neg (if you know what you're doing.) I use condenser and deffusion elnlargers, but am keeping an eye out for a deal on a used dual tube cold light system.
Bryce
Well-known
Trius-
I kinda think locally contrasty and perceived sharpness are the same thing, and in fact the very phenomenon the unsharp masking technique works on.
Whatever, I often like the sharp, grainy feel for pictures of "harsh reality" which is sort of what I'm after. Portraiture of small children would be very strange looking with this process!
I kinda think locally contrasty and perceived sharpness are the same thing, and in fact the very phenomenon the unsharp masking technique works on.
Whatever, I often like the sharp, grainy feel for pictures of "harsh reality" which is sort of what I'm after. Portraiture of small children would be very strange looking with this process!
Bryce
Well-known
Frank S-
Thats an interesting idea. I may try something similar with LED's soon. I see several benefits- no more changing filters during exposure, no more heat warping my negs, and no more burned out bulbs to deal with.
Now, I just need to get around to it.
Thats an interesting idea. I may try something similar with LED's soon. I see several benefits- no more changing filters during exposure, no more heat warping my negs, and no more burned out bulbs to deal with.
Now, I just need to get around to it.
BigSteveG
Well-known
seems i've raised a somewhat contentious issue. I've noticed the more I print, the flaws I find in my negs (especially older one), now want to solve the problem. I suppose experimentation is the only answer.
Bryce
Well-known
Not so contentious really; the difference is pretty subtle. And in any event, wet printers can only dislike each others' preferences so much nowadays since the community is tiny anymore.
Try it either way, you'll like it!
Try it either way, you'll like it!
sepiareverb
genius and moron
I was a dedicated cold-light printer for a long time, but have come around to the joys of the VC diffusion head. I had a Zone VI VC coldlight, but the contrast range was pitifully small- went from about grade 2 through to about grade 3. You could choose the bulb you wanted or have both, so I did lots of testing, finally decided it was not worth the longer exposure times.
As to required contrast of the negs, I never notcied all that much difference whether I printed my negs (developed extra) or other folks (usually lab developed normally). For graded papers I think cold-light is great, for VC the diffusion seems to give the benefits of cold light (dust-free negs, smoothness of tone) with the benefits of a condenser (short exposure times).
As to required contrast of the negs, I never notcied all that much difference whether I printed my negs (developed extra) or other folks (usually lab developed normally). For graded papers I think cold-light is great, for VC the diffusion seems to give the benefits of cold light (dust-free negs, smoothness of tone) with the benefits of a condenser (short exposure times).
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erikhaugsby
killer of threads
So kind of like the basic principle behind contrast filters for VC papers: yellow for the "Low" contrast emulsion layer and purple for the "High" contrast layer?FrankS said:
Ronald M
Veteran
They print like diffusion heads. A neg developed to print properly on either will make prints so close you need to examine then sise by side to tell them apart.
Condenser will have more contrast n the shadows, diffusion will show a little more detail in the highlight and have marginally smaller grain from fine grain 35mm films. Like I say, you have to compare them side by side and the neg has to be developed for the enlarger used so you need two identical negs to test this, one developed somewhat longer for the cold light.
Condenser will have more contrast n the shadows, diffusion will show a little more detail in the highlight and have marginally smaller grain from fine grain 35mm films. Like I say, you have to compare them side by side and the neg has to be developed for the enlarger used so you need two identical negs to test this, one developed somewhat longer for the cold light.
Trius
Waiting on Maitani
Ronald M...diffusion will show a little more detail in the highlight and have marginally smaller grain from fine grain 35mm films. [/QUOTE said:Like I said, 4x5/LF is where it's at with cold light.