Projection Resolution - Enlarger vs. Digital Projector

[Daniel Balfour]

Here's a thought -

Okay so it's more of a question.

How would the projected resolution of a traditional enlarger (assuming a decent lense like say... Componon-S) compare with the projected resolution of a digital projector hooked up to a computer?

- Can't wait to hear this one! If there's even a chance....

 

[keithwms]

Do you mean one of those 800x600 projectors that people use for powerpoint lectures? They might be adequate for a teen tiny print. But actually I was considering doing this kind of printing because I had in mind using the pixelation for effect. Haven't tried it yet though, I was mostly concerned about the lens (the unit I have at work won't focus so closely).

Or do you mean one of the high end De Vere digital enlargers?

Let me quote Jerry Lebens in Black & White Photography, November 2007, speaking of the 4mp De Vere from 2004:

"At 10x8 [those crazy brits!] they were virtually impossible to tell from hand prints but, as print size increased and approached 300 dpi (at 16x12 in), some images began to exhibit pixelation..."

But according to him, the new 504DS is 17mp and prints up to 20x24in convincingly by dithering. Costs a bloody fortune though.

I guess all these projectors should give straight 8-bit tonality and with dithering could offer effectively continuous tone, so I don't see any disadvantage there with respect to straight traditional prints. [Kindly do not quote my words on APUG ]

Of course nothing beats a contact print. There's no enlarger lens imposing its own limitations....

 

[Daniel Balfour]

Keith,

Well, originally what I had in mind was a simple digital project (yep, the PowerPoint kind). The idea behind it being the ability to print BIG onto surfaces coated with Liquid Light and the like (murals, huge canvas, etc.). Being that this is most definitely an alternative process (and thus, a departure from the literal), I'm wondering if I could get away (resolution-wise) with one of these cheap-ass gizmos. Might even consider adapting a Schneider lens onto the thing - a machine shop would probably be of some help here.

The advantages, should the hopeful venture succeed, are quite obvious:

The ability to print first-gen directly onto emulsion. The stronger light source. The portability.

I know I'm probably being optimistic, but I'm hoping that for my purposes (more abstract, gritty, nudes) it might work?

I can't seem to get the point of spending so much loot on the DeVere unless you're a pro lab or have other $-related applications. For myself, an avid (or more like obsessed) hobbyist, I can't see why I wouldn't stick with digital negatives. I mean if it's just printing on paper right?

I'm rambling as usual. Looking forward Keith!

-Daniel

 

[Daniel Balfour]

Oh one other thing -

I did a search for the DeVere model you quoted above and landed another thread on here where someone talks about some high-tech flavored film recorder. Something with lasers? I dunno.

If you recall a while back I was avidly pursuing the subject. I'd love to have a sure-fire home-brewed way to print (or otherwise produce) actual *negatives* from digital files, sans the recorder. These things are getting old fast. Practically no one even maintains them anymore. I was looking at a Pollaroid FR a while back as well. Thing is, most of them are only 35mm. Those that can handle MF are exorbitantly expensive.

Yet another ramble....

 

[keithwms]

Why not get an LVT and slap it on a projector or enlarger. I have a little beseler with a head that rocks back 90 degrees....

An LVT might give you enough nonpixelated res for a wall mural even if you just get a 35mm or medium format slide made. As I recall LVTs can print up to ~3000 dpi or so.

If only moderately worried about pixelation, you might try the following. Do a base exposure with a homemade anti-aliasing /diffusing filter over the lens. Then do a "sharp" exposure over that, without the diffuser in place.

 

[Daniel Balfour]

Thought about the LVT route, there's one place that does'em, I forget the name, think their out in SF. Last I spoke with them a 4x5 LVT was around $50 a pop! Are those done with lasers?

I like the idea of a stocking base exp and then a normal exposure but that would require the neg. If I had a neg I'd probably fiddle around with different tricks until I get something I'm happy with. In the meantime I'm all for diginegs! Next project will actually consist of trying to simulate an ambrotype using digital positives.

What's your take on picking up a used, el-cheapo film rec off of ebay for what I'd like to do (photo murals)?

 

[keithwms]

Yowza, I don't think I'd touch a used film recorder with a 100 ft pole, I have no clue about maintenance for something that's no longer even being made. I'd sure love to have a working one though

I'd be inclined to pay the price for the LVT and be done. Places like Chicago Albumen will curve your digital file optimally for your specific print type.

There are some folks here who have experience with film recorders, perhaps their view is less pessimistic than mine.

 

[Daniel Balfour]

I wouldn't be overly worried about getting a funtional unit (film recorder I mean). Refurbs are still offered by a subsidiary of Polaroid. The maintenance isn't an issue actually - least not for the models I was checking out. LVT's on the other hand are the real dying species.

In your personal experience, how does a film recorder neg compare to an actual (optically exposed) neg?

 

[keithwms]

In your personal experience, how does a film recorder neg compare to an actual (optically exposed) neg?

I'm afraid I can't answer your question in a way that's relevant to your purpose- I've only done contact prints and minor enlargements. Those results have been indistinguishable (to me) from my results with original negs.

But it seems to me that a ~3000ppi neg on 4x5 enlarger would give undotted 10x enlargement, so... 40x50 inches. If you need bigger then you could use an 8x10 enlarger that'd get you to > 6 ft.

Mind you, the dotting you see from a blown up LVT neg probably isn't quite as offending as square pixelation, so you could probably push the enlargement a bit more than 10x.

Incidentally, Chicago albumen sent me an LVT sample at 3048 ppi or whatever their max res is, I can provide that if you wish.

 

[nworth]

A good enlarger with a good lens will give you better than 150 lines per millimeter at the negative, or better than 5400 X 3600 on a full 35 mm frame (more for larger formats). A very good digital projector will give you a 1280 X 1024 pixel image, and most only go 1024 X 768. The resolution measures (pixels vs. line pairs) are not completely comparable, but this gives a good idea of the relative resolutions. The enlarger is capable of much more detail.