Gauging Interest: Enlarger back for LF Camera?

[Dr Croubie]

So this is an idea I've had in the back of my mind for quite a while now. There's a fairly good chance that I'm going to build one (or more) of the options below at some point for myself. What I'm interested in knowing is who else here would want one, what would you want, and what would you pay for it?
I know this kind of thing has been done before, and a lot of people have hacked LED light-panels into enlargers, but this would be a dedicated-design and hopefully work and look a bit better, especially if I can incorporate some of the 'fancy' things listed below.

The Concept
In short, it's a back to turn your camera into a diffusion enlarger. You take the back off your camera, mount your negative into this back, stick that on your camera, turn it on, and you've got an enlarger.
Another use would be as a projector, so all us LF chrome shooters could really project them huge. That includes Travelwides (I'd make sure it fit them), imagine taking 4x5 chromes and projecting them on a wall almost anywhere (does anyone want a battery-powered option?)


The Hardware
Basically, starting from the lens-end, there'd be a piece of optical glass, then any cardboard masks you want, then the negative, then ANR glass. A bit of space, then a diffusion plate, maybe more space to the bank of LEDs on a huge PCB, then controls/drivers behind that.
It's possible to do without the first bit of glass and masks and use clips, but then you're stuck with one format, ie 4x5 on 4x5 only. With masks and glass you can do 4x5, 9x12, 6x12, 6x9, 6x7, etc all in one 4x5 unit.


The Size
Originally, I was only going to aim this at 8x10". Reasons being that 4x5 enlargers are a lot easier to come by and a lot more common than 8x10 enlargers. But then, so are 4x5 shooters, so there might be more of a market there. If there's interest, I'll do both.
For 8x10, the entire back would come off. That means that there would be a Calumet/Cambo version (like I've got), a Calumet 'Monster' version, a Deardorff version, a Toyo 810 version, a Sinar version, etc etc. Lots of design work (for me) in getting a sample of each back to make sure it fits properly (any donations/loans/CAD-models would be appreciated). The PCB would be the same, only difference is the mechanical housing to fit into the camera.
For 4x5 it's easy. Graflok-mount and be done with it, one version.
Either way, I will endeavour to make sure that the film plane on the enlarger-back is in exactly the same spot as when taking. So you can even focus on your easel using the Ground Glass with the lights on, then swap to enlarging back and it will project exactly as focussed.
5x7" and Plate sizes are also possible (as are ULF, depending on how big a PCB I can get made), but again I can't make anything without having a back in front of me or an accurate CAD model. So they're probably not possible unless you're willing to lend me your camera to test (or make your own mechanical mounting bits) plus probably pay extra for the lower economies of scale.


Pros/Cons
Mostly the same as any other horizontal camera-cum-enlarger vs a dedicated unit.
Pros:
- It's smaller. This wouldn't be much bigger than 3-4 film-holders stacked up. No huge floor-standing 8x10 enlarger the size of a fridge taking up precious darkroom space that could be better used for a fridge full of film instead.
- If you can shoot it, you can enlarge and/or project it (except 617s on a 4x5 extension-back, but I'm putting them in my 8x10).
- Movements: Camera-dependent of course, but you can tilt and shift to correct perspectives at print-time if you want.

Lenses may be a pro or con depending on how you look at it. Enlarger lenses do come in shutters but are rarer than screw-mounts, so if you can't get one in shutter you'll have to hack one into a lensboard. Or just use your taking lens as enlarging lens, it may not be optimised for 2x-10x enlargements but you're still probably better off than taking on a smaller format (like 6x7) and enlarging more. LF enlarging lenses are rarely faster than f/5.6 so the speed is about the same as your taking lens.

Cons:
- It's horizontal, so you'd need a vertical easel. Or get a good stable tripod with head that moves 90-degrees and shoot at an easel on the ground.
- It'd be harder to ensure the film is absolutely parallel to the paper, but again you can compensate with tilts etc, and GG focussing should help with that too.
- I wouldn't be able to give definite 'Grade 1', 'Grade 2' settings with the RGB LED option. It'd be more of 'softest' and 'hardest' for split-grade, and 'teststrip and see' for anything in between. For dedicated worshippers of calibrated workflows who want (and can actually tell the difference between) 1/4-grades, you'll either have to spend a lot of time calibrating this too, or get the white LED option and use your own filters.
- Just on the colour of LEDs, yes I realise that there are different ways of making a 'white' LED and that RGB LEDs also have different colour-spectra and peak wavelengths. All of this will be teased out and tested in prototyping.


The Light and Colour
There are a few options here, and this is where I'd want the most help deciding what to invest time in (porque no las dos?)

- Single Colour White: All the LEDs will be the same, either warm-white or cool-white. Easy enough to make both from the same PCB design by just mounting different LEDs before manufacture. So you can have either, but if you want both you have to buy two. On the plus side, it'll be a lot brighter than the other versions, but to use as an enlarger you'll need CMY and/or MG Filters.

- RGB: This is where it gets tricky, and my inner-nerd comes out. By mounting RGB LEDs, you can get any colour you want by fiddling with sliders. No filters needed. Lots of other possibilities listed below in the 'fancy controls' section.


The Controls
One thing I hate about my current (LPL6700) enlarger is that when I adjust the CMY dials (esp for split-grade B+W), the head invariably moves and/or wobbles. So I plan on having a separate control-pad with a cable (wireless if I really want to nerd it up), with the switches, dials and sliders, maybe even a separate start/stop foot-switch if there's interest in one.

- Basic: Controls for the White-LED option would be just an on/off switch, and an intensity dial. A timer wouldn't be that hard to implement either, so no more metronomes for me, and a lot more accurate and repeatable.

- Intermediate: Controls for the RGB option would be the same as above, plus a slider for each of the RGB channels. A few saveable 'presets' would be handy, ie one would be pure red for focussing, pure Blue and pure Green for Split grade, etc. Being able to set times on each colour will be great for split grade, eg set 12 seconds soft grade, 5 seconds hard grade, press start and it just does it automagically. Or press start, it does soft grade once, beeps and turns the lights off, then you get your dodge/burning tools in place, press start again and you get to dodge/burn for a set time, then press start again and it goes to hard grade, etc, program it how you want. UI for this might get harder to make user-friendly, especially trying to make it all dark red so it doesn't fog paper.

- Fancy: There are a whole lof of options I can put in fancy, but it'll get expensive.
- For one, bluetooth and a phone app with no control pad. It's a bit out of my current capability but it'd be a good way to learn skills that would be very useful to my future career prospects so I wouldn't mind trying.
- Individual LED controls, so you can graduate the intensity, or turn some LEDs off. eg in a recent photo of mine, I burnt the sky (almost exactly half the photo) for a minute after the initial whole-image exposure. Instead, if I could just turn off half the LEDs for that second exposure then I wouldn't need to dodge with a piece of card. Of course this will be very 'soft-edge grad' because of the diffuser, but it would be useful especially for landscapes (or even introducing vignetting in the final print of a portrait). For this I'd need one LED-Driver per LED, so it would get rather expensive and complicated, don't hold your breath on these ones.
- Closed-loop like one of those Ilford heads. I don't even know how they work exactly but if people want one, I'll investigate.


The Deliverables
There are again a few options of how to sell this thing. Funding would be via kickstarter, that's the easy part. But would you want to buy the PCBs, LEDs, and sliders etc and solder it yourself? (there could be a few hundred LEDs 1x2mm so don't say yes unless you're a masochist or very very poor).
The drivers also have very small pins, so it's probably best if I get the camera-mount bits reflowed professionally.
But what about the controls? I could make it controllable via arduino and open-source the code, I'm sure a lot more people could code in functions that I haven't thought of, then you can wire in extra bits if you want.
Or I could get the whole thing into a semi-professional-looking enclosure, all you have to do is plug it in and turn it on. Cheaper than buying your own arduino, but less expandable.


The Cost
This is the big unknown so far, and I've only done preliminary digging. Just on the LEDs, if I use 0603 (that's 0.06" x 0.03" or 1.5mm x 0.75mm) LEDs, I can get between 1000-1500 LEDs on one 8x10" board, and that would cost anywhere up to $500 (at element14 prices). Just for the LEDs, no PCB or controls. But that's at maximum-density (which would be the most even illumination, of course) and still probably very-much overkill. I haven't done any prototyping yet to see how many LEDs I'd need to get the brightness and evenness that I'd like (depends on the diffusion-material used and distance to LEDs), but I'm fairly confident I could get the single-white camera-mount board in at maybe $500. Could be as low as $2-300 if I can use less LEDs and get a good deal on reflowing and manufacture the rest myself. Or it could be $600, but I don't think it'd go much above that. RGB LEDs aren't that much more expensive so maybe an extra $100 more. Of course it'd be a lot cheaper (maybe 1/3rd to 1/2 the price) for the 4x5" version.
Control pad could be $1-200 for basic-white or $2-300 for RGB, or $0 to make-your-own from an arduino design I supply. I'd probably use the same controls no matter the size of the camera.
My question is at what price-point would this not be worthwhile to you, and you'd rather just get a regular enlarger? (if you can find one)


In general, this is a very long-term project I'm looking at, if I do decide to turn it into a kickstarter don't expect it to be up before early 2016, or in your hands before Dec 2016. Or if somehow 100 people like the idea I might put a bit more effort into making it happen sooner. And if noone likes it, well, I'll build one for myself anyway.

 

[snapguy]

I think I'll wait to see the prototype. Lots of blue skies here but not much else. I once asked an investor to fund a rocket-powered dragster and he said I had a dream there, not a concrete proposal.

 

[Christopher Walrath]

+1. I think interest may follow concrete results. Very interested to see the outcome, though.

 

[heespharm]

Your idea reminds me of this:



I used to tape the paper to the wall and project it with the graflarger back in my lf experimenting days


Sent from my iPhone using Tapatalk

 

[heespharm]

Wait a minute.... Hahaha look what I found in my photography closet



Forgot I even had it


Sent from my iPhone using Tapatalk

 

[Ken Nadvornick]

I'd be interested in such a concept. I've considered doing up something like that on my own, but honestly it's a triple back burner idea for me at present. And into the foreseeable future.

It's likely the only way I'd ever be able to experiment with modest 8x10 enlargements in my small 4x5-designed darkroom. No way in heck I'll ever be able to accommodate an 8x10 enlarger.

Ken

 

[Dr Croubie]

Wait a minute.... Hahaha look what I found in my photography closet
View attachment 102224

Yep, that's pretty much the idea I had in mind. But a much more modern, LED-based version. Big plus on LEDs is the heat, even at maximum-LED-density an 8x10 board will only consume 80W (again, the final board will be a lot less) and be brighter than a 500W incandescent solution. And these days LEDs are more efficient (and again more even illumination) than a few Fluoro tubes.
I know it's only really at the concept-stage, that's why my 'market research' has a lot of options.
The technology (of LEDs and drivers) is very mature, as is the way they'll be controlled (either 8051-compatible or Arduino via an I2C bus). I've pretty much decided on a MAX16826 driver for the first iteration (ie, not the individual-LED-control version)
Put it this way, if it were up to me to do this for myself, I'd be doing a 4x5 white-head specifically aimed at Travelwide shooters who want to project chromes, and an 8x10 RGB head for me to enlarge everything bigger than my current 6x7.
The only real unknowns (technology-wise) for me are the exact LEDs that I'll use (there are literally thousands of options), how many and how bright, and the material for the diffuser.

The prototype circuit-boards I'm going to start designing in a few weeks (once I can get my hands on a free Altium license again), the only other big unknown after that is where to get the PCB made and reflowed (but that's more a matter of choosing from the many options I already have).

 

[NedL]

I think it's a really neat idea and there are some other things about using the same lens for taking and enlarging that are intriguing. First, there's a kind of reciprocal compensation for falloff. But there is also a kind of symmetry about the light coming in one way to expose onto the negative, then out the other way to expose the print off of the negative. ( I recognize this is a bit silly, but I get a certain satisfaction enlarging prints using my el nikkor 50mm lens that were taken with nikon 50 mm lens.... there is a kind of "balance" that I like. ). Good luck with your project. In all honesty, I am such a tinkerer and enjoy making stuff, that if I want to do this an awful lot of the fun for me will be thinking it through and doing it myself, so I'm almost sure I wouldn't purchase something like this.

I've been mulling over a similar idea for a future box camera. My "gedanken concept" is simpler than your enlarger. I would build a "port" on each side of the camera that are closed when using as a camera. Then they can be opened to admit two bright lights angled at 45 degrees toward the back of the camera. This would create a projection reflective enlarger for paper negatives. Like BlindPig's enlarger, but also a camera.

Anyway have fun and good luck with it!

 

[DannL.]

Having owned and used a Kodak Enlarging camera I can say with confidence that as a horizontal enlarger it was a serious pain in the butt. It handled 8x10, 5x7, 4x5 and smaller plates and films, but required every inch of a 5 foot table to produce a 16x20 print. I found dodging and burning prints difficult with the paper on the vertical, while standing at the side of the easel. No thanks. Keeping different size papers on a vertical easel (board) was a challenge. I didn't keep the camera very long after that. But, I did make a 5x7 enlarger using a 5x7 camera, and that worked like a champ. It stood vertically using a regular tripod, and a DIY lamp-house sat on the back of the camera. With the camera on the vertical, and pointing down, you're not constantly fighting gravity at both ends of the business.

 

[Simon Howers]

LED panels

Yep, that's pretty much the idea I had in mind. But a much more modern, LED-based version. Big plus on LEDs is the heat, even at maximum-LED-density an 8x10 board will only consume 80W (again, the final board will be a lot less) and be brighter than a 500W incandescent solution. And these days LEDs are more efficient (and again more even illumination) than a few Fluoro tubes.

I built a horizontal enlarger from a Deardorff 10x8 camera a couple of years ago by making a lightbox to fit on the focussing screen mount. It uses a 40W 600x600 LED ceiling panel from an English supplier called LED Hut.
I print 5x4 and WP, so I just made up cardboard mounts to hold the film.

It is certainly not as convenient to use as a vertical enlarger but it's much cheaper and lighter, folds away
really neatly and can still be used as a camera.

 

[paul_c5x4]

if I use 0603 (that's 0.06" x 0.03" or 1.5mm x 0.75mm) LEDs, I can get between 1000-1500 LEDs on one 8x10" board.

Have a look at some of the other LED heads that people have built. Most of them use a handful of >5W LED modules on a 25mm grid - I don't think you would need anywhere near as many LEDs as you suggest.

 

[Dr Croubie]

Have a look at some of the other LED heads that people have built. Most of them use a handful of >5W LED modules on a 25mm grid - I don't think you would need anywhere near as many LEDs as you suggest.

Yeah, I know, that's just at max density (I hope I don't have to pack them that tightly, I do have to hand-solder the prototype. I can, but would prefer not to).
I have considered using less, higher-power LEDs, but then that would be a lot less even, more like a few 'hotspots' and darker bits in between.
Realistically it could end up somewhere closer to 500, ie on a 10mm-grid, or even 250 on a 15mm grid, then I'd have the space to move up to 0805 or 1206 size, or even 5mm through-holes.
All of that would come through the prototype stage.
The biggest benefit I can see now to more of smaller LEDs is the evenness of illumination, but also the sheer intensity to use it as a projector or to keep exposure times short. But if less works just as well then that may be the way forward.

 

[Neal]

My 2 cents: Used 4x5 enlargers are really cheap. Maybe for an 8x10?

Neal Wydra

 

[MattKrull]

As someone without the space for a 4x5 enlarger (my darkroom is temporary unit I setup in my phone-booth sized basement bathroom), I definitely like the idea. The only reason I haven't picked up a 4x5 yet is that I can't make enlargments from it. I've seen the Graflarger backs online, but every time I have the cash and will for one, there are non available.

Personally, I don't care for a phone based interface. I like using a darkroom because I like the tactile process. Give me simple knobs (off the head is fine, but not wireless/battery powered). I'd be willing to pay $200 for a simple RBG 4x5 that had presets for MG 00 through 05 in 1/2 step increments (same as the Ilford MG filters). But that is because I don't understand the hard and soft you talk about. So long as there is a simple way to work out what I need, I'll be happy (ie MG 2 1/5 = 1 on this slider and 2 on this slider).

I think being able to tap into the travel-wide crowd (and let them use it as a projector) is a fantastic idea.

 

[ic-racer]

A simple device like that was not practical in the 'incandescent' era due to the heat, wattage and size of lamp(s) needed. LEDs may be a workable solution, but I'm waiting to see what type of exposure times you will have for 40" prints from 8x10" negatives.

 

[David A. Goldfarb]

I agree that it isn't worth the trouble for 4x5"--plenty of Graflarger backs out there as well as very nice 4x5" enlargers selling for pennies on the dollar--but interesting for 8x10" and maybe larger. I'd consider it something to be used on a vertical copy stand, rather than horizontally.

 

[DREW WILEY]

Lots of old view camera and stand cameras have been turned into makeshift enlargers, but I don't understand why anyone would want to.
If you want that concept, you can pick up a used stat camera for next to nothing these days, or even a real enlarger, which would be far
more convenient to use. I'd get you awfully damn jealous if I told you about my latest free acquisition, even in the 8x10 film realm. They'll
almost pay you to haul used lab stuff away these days. And some of that old gear was built to last a hundred years.

 

[paul_c5x4]

Personally, I don't care for a phone based interface.

I'd agree. Not everyone has (or wants) a phone.

One thought did occur to me..... If the boards were made modular, based around 5x4 format, you could cover 10x8 or even 16x20 by connecting multiple modules together.

 

[MartinP]

Phone interface? That means that it will potentially require re-writing every time the phone is updated else the enlarger will have the same lifetime as a phone OS ie. measured in months. The quality of the output will be completely irrelevant if possible purchasers think it is even remotely likely that the device will be scrap inside a year. Remember, these are users with cameras that are frequently decades old, and still going strong.

Regarding light-sources, have a google on large-format forum and find the posts where someone used a high-quality light-box as a simple and effective enlarger light-source. That will save you massive amounts of design-time and investment costs, leaving 'only' the enlarger mechanicals to worry about....

 

[Dr Croubie]

Yeah, the phone idea is a very very outside chance, and will probably only happen (if at all) for the individually-controlled RGB option - the paradigm would be that there is an outline of the LED panel where you can draw with your finger where you want to increase or decrease brightness analogous to dodging/burning. It's not going to happen straight up, and there are probably very few people who would actually want or use it, but it's 'just a cool idea' that excites this engineer. Having to re-write apps is certainly a turn-off, although that could just be a recompile depending on what language/platform I went for (I also don't have a fancy phone, so I'd have to buy one too).


Anyway, back to the realistic bits. Just for shits'n'giggles I mounted my camera vertically above an easel, and there's more than enough room in there to work.

It's a Toyo 45G (not a light camera, but at 6kg it's less than my 8x10), on a Vanguard Alta Pro 283CT (load capacity 8kg), with Arca Swiss Monoball P0 (max load 20kg, probably on-axis, which this was not). The easel is 'only' 16x20", the biggest I've got lying around for now (there's no point buying bigger until I get this LF enlarger happening).
Despite being less than ideal, it certainly held the weight fairly well and with no more (but not much less either) wobbling than my LPL6700.
I've got a beefier tripod for my 8x10 (Vanguard Abeo Plus 363CT) which would hold the weight a lot better (except it's only got a Sunway DYH90R levelling-base so it can't point straight down, I'd need a 90-degree adapter for it).
But still, besides needing said adapter to point straight down, it still fits in the 'if you can shoot it you can enlarge it' category.

I did also think about modular, actually making things modular is one thing I like doing. The biggest problem is in the joining of the PCBs, both mechanically (to retain flatness) and maintaining the distance between LEDs for even illumination without getting a dark or light stripe. Certainly doable, but a lot easier with bigger LEDs on a bigger spacing than smaller close-together. I did think that eventually someone would want a 7x17" or something, so I'll investigate modularity too. 8x10 is *probably* better off (cheaper) as a single PCB compared to work in joining, but I'll check it out.

 

[MartinP]

I'll just mention again "Artograph LightPad Lightbox". The diffused, cold light source for LF enlargers question is a problem that is solved. I can understand that making something oneself is satisfying, but it costs more and uses up more valuable photography time. No one lives forever.

 

[BetterSense]

The best part of the original pitch was the idea about using it as a projector. A flawed idea, since you need much more light for projecting than you do for enlarging, but it makes me curious about if it's possible to make such a light source for projecting.

 

[adelorenzo]

I am interested in this. I have space for an 8x10 enlarger but getting one up here is prohibitive. My plan has been to convert an old 5x7 Eastman by replacing the head with a cheap 8x10 camera like a Calumet or Cambo. If I could get a plug and play light source that would be very cool.

 

[Sirius Glass]

My interest? Somewhat less than none.

 

[rmann]

I'll just mention again "Artograph LightPad Lightbox". The diffused, cold light source for LF enlargers question is a problem that is solved. I can understand that making something oneself is satisfying, but it costs more and uses up more valuable photography time. No one lives forever.

I am using an Artograph as the light source on an 8x10 enlarger, great product - unless you like to tinker just get one of these. Check posts on large format forum for lots of information.