Help... Process camera vs imagesetter

[realmstar]

I understand image setters are easier and process cameras are outdated. But I have a question only for people who used to use process cameras. I would really love as much feedback as possible from people who have used process cameras back in the day.

Say we have a high detailed fine line black vector file image that is 8x8" (100%). If we print this out enlarged at 400% (24x24") on white photo paper where its crisp black images then take a picture with the process camera and reduce it back to 8x8" (100%). My question is if we do it this way can this create a perfect crisp negative with the same quality as an image setter would create at 3000dpi or will the image setter be able to still do better?

I figured if the picture is taken of it enlarged at 400% where the camera can see it clearly and big before its reduced back to 100% the quality will be the same?

Can anyone tell me if done this way if a process camera can create the same quality as an Agfa 1000 image setter at 3000DPI if used this way?

 

[Point918]

Haven't used a process camera since school in the 70's and for good reason!
If your original image is vector based you cannot get anymore detail of if it than imaging out of your Agfa device at it's highest resolution. The process camera analog steps you describe will no doubt NOT improve image quality. Vector file image resolution is only limited to the output device limitations.

 

[gordo]

Adding to Point918's response - the "3,000 dpi" of the Agfa AccuSet 1000 (actually 2400 dpi or 3600 dpi) is not the resolution of the imagesetter. It's the addressability of the device. Ie. it can expose the centers of spots of energy 1/2400th or 1/3600th of an inch apart - but the size of the spots of exposing energy are not 1/2400th or 1/3600th of an inch across. They're larger.
I would speculate that if you tested it by imaging a graphic as small as you can using a process camera vs an imagesetter - the process camera would be able to image a graphic clearer and smaller that the imagesetter. This is because the particle sizes that form the image with high-resolution film is around 0.2 - 2.0 microns while your imagesetter would be lucky to achieve a 21 micron-sized feature.

And yes I've run a process camera in the early 70s.

On a dotted line related note - the finest halftone lpi for the Agfa AccuSet 1000 is 175 lpi. I have books printed around 1900 (before imagesetters) that are at 400 lpi.

 

[realmstar]

If we have 0.1pt thin lines we want on film and we print it out at 400% (0.4pt) and the camera snaps a picture reducing it back to 100% (0.1pt) why would this not work? I was told a camera can make a negative out of anything it can see and if the image is big it makes it easier to see it and then you just reduce it back to the size (100%) you need for a high quality negative?

I mean this is what people did in the 70's and 80's and there is printed lines at 0.1pt at that time so cameras would have had to reproduce negatives with fine lines that thin doing it with a process camera? So couldn't it produce a negative with lines that thin as good as an agfa image setter giving what I said? If not then how is what I said incorrect and why? Sorry I am just trying to understand better?

We have a next to new high end process camera made around 1998 we would like to buy from some place for just a few hundred dollars and figured we could make negatives with lines that are 0.1pt thin on it?

 

[PrepressPaul]

I agree with gordo with regards to the particle size of film vs the imagestter, on very small work. It's mathmatical sense. I also agree that to test and measure is the only sure way to recognise the best method.
Something to be very careful about with the process camera on very fine work though, is to make sure you use f stop 22 and have your focus absolutely perfect. You can accidently choke or spread linework by being out of focus slightly, combined with under or over exposure.
I've spent countless hours in darkrooms in the early 80's. Good luck!

 

[realmstar]

What is f stop 22?

 

[Possumgal]

I used to have a boss back in the 80's that did the same thing. Had me paste up huge business cards, then shoot them down to size. It really didn't make any discernible difference to just pasting it up to size and shooting it.

One thing you might take into consideration is your film quality. If you're going for really fine lines with a camera, be sure to get fine-grained film. I forget what the nomenclature was, but we had one film for line work and the finer, more expensive stuff for halftones. Your film supplier can help you out with this.

Also, can your plates handle .1 lines?

 

[realmstar]

Halftone film can also do fine line work right? I was told you don't need film for line work you can use halftone film and get the same effect but halftone film just costs more. But if I was doing just line work would 150 halftone film or 300 halftone film matter for the quality of the solid lines? Or only if there is going to be halftones?

 

[JimBob53]

I used a process camera every day for about 10 years and a imager for about 10 years.... On the project you have presented I believe the process camera will give the best results.... as stated before the imager will have micron-size issues.

 

[PrepressPaul]

f stop 22 is an aperture setting on your lense. It's roughly the middle setting of the choices you'll have. It's proven to be the best aperture setting for the most accurate reproduction.
One trick to get perfect focus, is to open the aperture right up (ie to the biggest hole, letting the most light through), then use an eye glass on the frosted sheet on the film plain, to to make sure your focus is perfect. Then close the aperture down to f/22 for your exposure. You'll notice your exposure clock change as you flick through the various f stops.
I can almost smell the fixer . . .

 

[Slammer]

the "3,000 dpi" of the Agfa AccuSet 1000 (actually 2400 dpi or 3600 dpi) is not the resolution of the imagesetter

Don´t you mean "ppi?"
Ahh cameras, if I am correct some aspects of banknote printing still use two room cameras to get the fine details to banknote size.

 

[Odyssey]

Another consideration is that every time an image goes through a lens it degrades slightly, the degree of degradation depends on how good the lens is /aperture used.

 

[Repro_Pro]

If you have an optimized combination of camera, lenses, lighting, films and processing, operated by a knowledgeable, experienced camera operator - at best you will be able to achieve the quality of a very average image-setter.

Using a process camera nowadays makes economic sense only for low quality/very low volume of films.

BTW, optimum sharpness is usually 2 (click) stops below the widest aperture of the particular lens (APO lens is mandatory, naturally).

 

[gordo]

Just some clarifications are in order...from my dusted off my old (c1972) Du Pont tech manual. I was doing plate film for newspaper (the Calgary Herald) back then (in addition to doing fashion photography for the Bay's newspaper ads - crazy)
For f stop - for every change in reproduction size there must be a compensating change in exposure. You can adjust exposure by changing time or f stop. Typically the f stop range ia between f16-f32. There are formulas for both.
You use orthographic lith film (very high contrast film) to do both line work and halftones.
For doing halftones you place a "contact" screen over the litho film on the vacuum back. The contact screen has a continuous halftone pattern built in to it. This acts like a threshold array relative to the lith film. You can replicate the process digitally by following the steps outlined here: http://the-print-guide.blogspot.ca/2...tone-dots.html
The lamps that illuminate the copy board need to be placed so that they create even illumination at the film plane not the copy board. This is to compensate for light drop off caused by the passage of light through the lens.
There's more (100 pages) of instruction including dealing with OBAs in the copy paper - yup, OBAs were a problem even back then.

 

[realmstar]

So people here are saying that a camera can reproduce better quality then an image setter. And then there are a few people saying an imagesetter would do better quality. Including one person saying that the best quality a camera can do is only an average imagesetter at best. It's strange that there are such opposite answers. Who do I believe?

 

[gordo]

So people here are saying that a camera can reproduce better quality then an image setter. And then there are a few people saying an imagesetter would do better quality. Including one person saying that the best quality a camera can do is only an average imagesetter at best. It's strange that there are such opposite answers. Who do I believe?

Photo lithography is used to image the computer circuits used in imagesetters...hmmm ( http://whatis.techtarget.com/definition/photolithography )

 

[gordo]

Welcome to PrintPlanet. Similar to the actual industry itself, I'm afraid.

Everyone is entitled to their opinion...but not to the facts.

 

[Repro_Pro]

The original question referred to

a high detailed fine line black vector file image

.
So I propose to limit this discussion and take the famous USAF resolution test chart as reference:
https://en.wikipedia.org/wiki/1951_USAF_resolution_test_chart
Now to generalize, I'll say that for resolving the very fine line pairs in such an artwork, an average image-setter will be a MUCH better choice.
This generalization will hold even if you will do Transmission instead of Reflection artwork.

 

[Repro_Pro]

And, working in a darkroom under Red (Orthochromatic) safe-lights and spotting-out pinholes on a light table afterwards has its' merits, I am sure...

 

[gordo]

And, working in a darkroom under Red (Orthochromatic) safe-lights and spotting-out pinholes on a light table afterwards has its' merits, I am sure...

And don't forget your ruby tape, ruby litho film and goldenrod film support paper! Can you even get those supplies these days?