black and white drum printer

[nc5p]

There are many times when digital post processing is appropriate for some negatives. The shadow/highlight tool in CS2 comes to mind in complex scenes where dodging and burning are difficult to control. Therefore I'd like a way to print my black and white photos onto regular enlarging paper. I have this idea of building a drum printer. This would have a drum that spins around holding a piece of paper. The drum motor would either be a synchronous AC type or brushless DC driven by the computer. A fine threaded rod driven by a stepper motor (microstepped) would move either a blue/UV LED or blue laser. I could modulate this under computer control to match the image file. The light would have a small lens to focus the beam to a small point on the paper. In a few minutes it could print a digital image onto the paper and then you would just drop it into a tray to develop as usual. I don't care about color so I'm not talking about a full blown lightjet printer, just something small to go into the darkroom at home.

I am an EE and have designed motor drivers for both types of motors here and also designed laser driver circuits. Am I crazy or has anybody else thought about something like this?

Doug

[donbga]

There are many times when digital post processing is appropriate for some negatives. The shadow/highlight tool in CS2 comes to mind in complex scenes where dodging and burning are difficult to control. Therefore I'd like a way to print my black and white photos onto regular enlarging paper. I have this idea of building a drum printer. This would have a drum that spins around holding a piece of paper. The drum motor would either be a synchronous AC type or brushless DC driven by the computer. A fine threaded rod driven by a stepper motor (microstepped) would move either a blue/UV LED or blue laser. I could modulate this under computer control to match the image file. The light would have a small lens to focus the beam to a small point on the paper. In a few minutes it could print a digital image onto the paper and then you would just drop it into a tray to develop as usual. I don't care about color so I'm not talking about a full blown lightjet printer, just something small to go into the darkroom at home.

I am an EE and have designed motor drivers for both types of motors here and also designed laser driver circuits. Am I crazy or has anybody else thought about something like this?

Doug

Well I don't know if it has been done yet or not, but I've often thought that there would be a market for a device like this which would appeal to the home darkroom enthusiast.

On the other hand it sounds very similar to what a film recorder or image setter does with film not paper. Apparently those devices are quite complex and require a lot of maintenance.

Good luck,

Don Bryant

[avandesande]

I have thought about this too but instead would modify an inkjet printer. It probably wouldn't be that hard to modify the piezo pulses to work with high intensity led. Your idea might be more precise but mine would be easier to get going since you would alread have the computer interface solved.

[Helen B]

Wouldn't a laser printer be closer to what you want?

[Bob Carnie]

Doug

I have a laser printer *Lambda* which exposes from digital files onto any photographic emulsion. Currently we have been producing large 30x40inch fibre prints for exhibition on Agfa Classic.

There is a digital head that uses led technology *Deveere and Varichromat* I am not sure of the resolution quality on larger murals but I believe they are very good up to 16x20 inch prints.

The three imagers have different price points and support from the Manufacturer.
Lambda- 200K plus excellent support at 30k per year
Deveere and Variocromat- 50 k and I am not sure of the support or price.

[Michael Koch-Schulte]

Just playing Devil's advocate a bit Doug: Why not use a belt drive head system and a flat bed paper feeder (similar to an inkjet printer) instead of a threaded rod and drum. Isn't the drum going to take up more room and be more difficult to drive? I've toyed with the idea the notion of using a UV laser for UV processes like Cyanotype, VDB, Argyrotype, Platinum. Maybe, if you were going to all the trouble of mounting a laser you could spec one that was powerful enough to use on these processes as well.