Wet plate / artificial lighting [Archive] - Large Format Photography Forum

Jason Greenberg Motamedi

5-Oct-2011, 14:28

Florescents provide, I think, the best quality and cheapest source of artificial light for collodion and other color-blind (UV and blue only) processes. Mercury/HMI works great, but can get incredibly expensive, especially for the photographic market, and get really hot. Going to a indoor plant store will be cheaper, but make sure your bulbs have the right spectrum. Studio strobes work fine but you need a fair amount of power (>4800 ws), and in my experience the highlights in collodion postives tend to block up more than other light sources.

cyrus

5-Oct-2011, 14:44

Jason Greenberg Motamedi

5-Oct-2011, 15:11

No doubt mercury provides more UV light, but also consider the type of light source. Mercury will be a point source, very high contrast, so you may need to diffuse it; expensive HMI units for film often use Fresnel lenses to do so. Regular (tube) florescent bulbs don't need much, if any, diffusion because they are already so big (a potential problem). I haven't used the twisted compact florescent bulbs, so I can't say about them.

cyrus

5-Oct-2011, 17:44

I already have some Red Heads and fresnel tungsten flood lights- will try putting mercury vapor bulbs in them.

Anyway, light control is something to worry about that later - for now I was just curious what sort of artificial light is workable with wet plate. If I am going to be stuck needing/using only sunlight, that makes the attraction of wetplate substantially less interesting for me, under current circumstances esp as winter comes along and the days get shorter. My real goal was working towards coating my own DRY plates anyway.

I'm surprised though that there isn't much other information on artificial lighting for wet plate available. I guess most practitioners are "reenactors" who naturally work outdoors anyway. I see references to flourescent but they tend to be contradictory, and tend to say that it only works for long exposures, close up - which means it doesn't really work all that well. I don't see any references by anyone to using mercury vapor or blacklights. Is this because it doesn't work, or because no one has really tried it (which seems unlikely!)

Joe Smigiel

5-Oct-2011, 21:38

I would imagine mercury vapor lights would be very uncomfortable for the sitter in terms of visual intensity and heat. After reading all the wetplate posts on the subject I think your best bet is probably some common relatively inexpensive daylight 4- or 8-foot tube fluorescents in a large bank.

Another alternative might be commercial black lights used in stage performance. I've never heard of anyone actually using them for wetplate, but I think they might be worth a try. "American DJ" is one brand.

After looking at spectral data I intend to experiment with some AQM aquarium actinic fluorescent lamps.

As Jason relates, high-powered electronic flash units will also work. I have successfully used a Speedotron 4800ws head or a 9600ws quadlight for wetplate in the studio.

Surprisingly, I also have had success with a quartz 1000w FEL lamp in a Lowel fixture. Exposures were about 22 seconds f/8ish with the lamp about 4 meters from the subject IIRC. In retrospect, I would not expect such a hot light to have a proper spectrum for wetplate, but the exposure was in the ballpark of what others get with CFL arrays of 9 or 16 lamps up close (e.g., 5-6 seconds at f/4).

cosmicexplosion

6-Oct-2011, 03:41

i was just looking some where secret and not very obvious for mercury lights and came across the information that cars use mercury lamps

which means that all you need in your dark room, is a car!

but the lamps are 12V and throw some light

most of the other globes seemed to be designed for large warehouses.

i just bought 2 600 watt flashes for using with wet plate

and as they arrived yesterday i am keen to try them out.

i bought them as i saw them used on the up coming doco about wet plate called artist and alchemists.

they are beauties as they have battery and ac. light battery, will be taking em every where.

think it will solve the old look in portraits out side.

i also booked marked a u.v light for home security, mostly invisible, but @ $90 bucks, it will remain invisible.

Scott Davis

6-Oct-2011, 05:25

If someone would like to try it out sometime, I have a 2400 WS Calumet Elite pack and a head with a flash tube in it that does not have UV-blocking coatings. As I'm not really doing wet plate at this time (I've decided to focus my energy on my gum and platinum printing), it would still be interesting to see the results from it. My studio is in Washington DC - all you'd have to do is bring your chems and plates, as we have a decent sink in the bathroom (it's an old industrial space, so no worries about spilling chemistry).

Sevo

6-Oct-2011, 05:28

I already have some Red Heads and fresnel tungsten flood lights- will try putting mercury vapor bulbs in them.

Mercury vapour bulbs look as if they fit regular incandescent lights, in having Edison sockets. They do not - you would need a ballast for them (unless you use mixed fluorescent bulb - but these have less light output than the highest power incandescents for the same socket).

Edison thread incandescent lights can be replaced with high power CFL lamps - but these aren't UV heavy either, and conserve energy rather than increasing the light output significantly.

Besides, your readheads and fresnel lights will be halogen, with different (G or PAR) sockets and a small reflector that would not work with the huge old-school mercury bulbs even if you'd swap sockets.

Unless you stumble upon some ancient arc lights, tanning bed UVA tubes might be your best bet - these are predominantly UV (and that without any in the strongly unhealthy UV-C range), easily obtainable and cheap, and fit standard lighting fixtures and power converters. HMI would do, of course - but they are expensive unless some friendly film company lets you borrow them for free.

Robert Hughes

6-Oct-2011, 06:48

I already have some Red Heads and fresnel tungsten flood lights- will try putting mercury vapor bulbs in them.
You could also screw sticks of dynamite into those Red Head sockets. You might need a ballast, though... and about a foot concrete between you and your lights. :eek:

cyrus

6-Oct-2011, 07:32

Yeah in looking over the redheads it doesn't look like it is worth the effort to modify them to take mercury lamps - I WAS thinking of just removing the old sockets and installing new ballasted sockets. But everything I've read says collodion requires a massive flash pop (9600!) and with my f/9 process lenses, that's not practical. Similarly, the regular CFL and tube flourescents seem to only work if you use massive banks and place them really close to the subject, according to what I've distilled from the discussions. So I think, theoretically speaking, mercury vapor lights are the most effective way to go, including and probably especially mercury vapor UV lights, the sort that are used in dance clubs. Now, does this create a natural looking skin tone on collodion? Who knows!

Sevo

6-Oct-2011, 08:10

mercury vapor UV lights, the sort that are used in dance clubs.

While technically mercury vapour, these are generally called "fluorescent light" - "mercury vapour" is usually only used when talking about high pressure discharge lamps, as these come in a fairly wide variety of different discharge media...

Black lights as used in dance clubs are filtered to be low power and half near UV, half visible deep blue so that they cannot cause eye or skin damage - their energy in the UV spectrum is modest, not significantly higher than that of daylight FL tubes of identical wattage.

BarryS

6-Oct-2011, 08:13

Cheap spiral CFL bulbs leak UV like crazy. I use a couple of Fotodiox C-1600 fixtures (http://www.fotodiox.com/product_info.php?products_id=78) with a 4x4 grid of edison sockets. I fill them with cheap contractor-pack 26w daylight CFLs. With two units, my wet plate exposures are very fast.

Process lenses for wet plate studio work make no sense at all--you're better off hunting for a fast old portrait lens--they're not all expensive. An f/4 or f/5 lens will only need a quarter of the light of your f/9 process lens.

Jason Greenberg Motamedi

6-Oct-2011, 08:24

In the past when I need small I built lights based on four 55w 21" 5500k fluorescent bulbs from an aquarium supply, but these weren't so cheap, and the Fotodiox uses twice as much power. If course, this might not equal twice as much light, but still, it looks like a nice product. How is the finish on it Barry?

Sometime back I adapted a 1K Mole Fresnel and plugged in a 4800ws Speedotron head. The result was disappointing, as I lost nearly a stop of light compared to a 22" beauty dish. I have a few more of the 1Ks and had thought about putting in a Mercury bulb, but this convinced me the effort would be wasted.

cyrus

6-Oct-2011, 09:32

Process lenses for wet plate studio work make no sense at all--you're better off hunting for a fast old portrait lens--they're not all expensive. An f/4 or f/5 lens will only need a quarter of the light of your f/9 process lens.

That's fine advice for an LF and smaller camera, but try finding (and paying for) an f/4 or f/5 lens for a 20x24 camera, not to mention have that camera front standard support a 10-20 lb lens! :) (That is where I'm going with this - see if I have a ULF camera built I don't want to be limited to only being able to use it outdoors or next to a window. If I can't find adequate indoor artificial lighting, then such a camera will be a white elephant for me)

But in any case as far as I've seen the report on various discussion formums, even the use of CFLs with a fast lens requires a min of 20 sec exposure and/or very small distance from the subject to the light.

Now here's something worth trying...
Eliminator EBK-400 Black-400 High Powered 400 Watt Blacklight (http://www.ebay.com/itm/Eliminator-EBK-400-Black-400-Hi-Power-Blacklight-/150661021591?pt=LH_DefaultDomain_0&hash=item231418bf97)

cyrus

6-Oct-2011, 09:47

While technically mercury vapour, these are generally called "fluorescent light" - "mercury vapour" is usually only used when talking about high pressure discharge lamps, as these come in a fairly wide variety of different discharge media....

THIS (http://www.ebay.com/itm/Eliminator-EBK-400-Black-400-Hi-Power-Blacklight-/150661021591?pt=LH_DefaultDomain_0&hash=item231418bf97) looks a lot like a HID mercury vapor bulb not a fluorescent bulb. Am I right? :confused:

E. von Hoegh

6-Oct-2011, 09:59

Thanks Jason. I was thinking that there are industrial mercury vapor bulbs/fixtures that I can use and which are cheaper than those for the photographic maket. The spectrum (http://www.neon-lighting.com/articles/Types%20of%20Lamps.htm) for mercury vapor lamps seems to have a large spike for UV beats the pants off of flourescent.

Look for old outside lighting fixtures that take MV lamps.(And have good ballasts)

You'll need to diffuse them, but you'll have oodles of light. Make sure your diffusion material is UV transparent.

The tanning bed tubes are a good option as well.

E. von Hoegh

6-Oct-2011, 10:00

cyrus

6-Oct-2011, 10:03

Didn't think so - worth investigating?

Sevo

6-Oct-2011, 10:39

THIS (http://www.ebay.com/itm/Eliminator-EBK-400-Black-400-Hi-Power-Blacklight-/150661021591?pt=LH_DefaultDomain_0&hash=item231418bf97) looks a lot like a HID mercury vapor bulb not a fluorescent bulb. Am I right? :confused:

Probably - looks like a high-pressure street lamp. But the UV output should be very limited unless these ones are some illegal high-risk device. Approved stage or club blacklights are supposed to be UV safe, and most of the light would vanish in the filter glass.

BarryS

6-Oct-2011, 11:32

In the past when I need small I built lights based on four 55w 21" 5500k fluorescent bulbs from an aquarium supply, but these weren't so cheap, and the Fotodiox uses twice as much power. If course, this might not equal twice as much light, but still, it looks like a nice product. How is the finish on it Barry?

Jason-- For a $135 fixture, I'm very happy with the build quality of the Fotodiox units. I've got a wide variety of lighting instruments--Hensel, Balcar, Norman, Arri, and Kino-Flo--and the Fotodiox units are pretty decent in comparison.

@ Cyrus-- 20"x24"? You're going to need a lot of UV for an f/9 portrait sitting. That's a lot of radiation. You can run 4-5 Fotodiox units off a 20 amp circuit, but 6-8 units would be painfully bright. There's not going to be any easy solutions for what you're trying to do.

cyrus

6-Oct-2011, 11:41

There's not going to be any easy solutions for what you're trying to do.

That's what I'm starting to think. :(
Seems to me that ULF wet plate requires easy access to outdoors shooting, which would impose various restrictions on your photography style/content. If that is the case, I may still go with a ULF plate camera but only if I manage to make dryplates that respond to "normal" light. So I guess time to buy gelatin instead of collodion...

cyrus

6-Oct-2011, 11:44

Probably - looks like a high-pressure street lamp. But the UV output should be very limited unless these ones are some illegal high-risk device. Approved stage or club blacklights are supposed to be UV safe, and most of the light would vanish in the filter glass.

I think "UV safe" means no UV-C radiation (the type used for sterilization in hospitals) but it has to have UV light because (back in my clubbing days ;) ) these sorts of lights could make your girlfriend's teeth glow on the dance floor, 50 feet away!

E. von Hoegh

6-Oct-2011, 12:09

I think "UV safe" means no UV-C radiation (the type used for sterilization in hospitals) but it has to have UV light because (back in my clubbing days ;) ) these sorts of lights could make your girlfriend's teeth glow on the dance floor, 50 feet away!

Due to the fluorescent "whiteners" put in toothpaste. Laundry detergent, too

cyrus

6-Oct-2011, 12:56

Thinking about this some more - I wonder why UV light works for collodion at all. Doesn't the glass on the lens block the UV, leaving perhaps only the blue/purple light to actually cause the reaction? In that case, instead of getting a UV light, I should experiment with blue colored lights! (If your lens uses quartz, that would be different but I am sure there are no quartz lenses)

In fact we still have to pin down the spectral sensitivity of wet plate collodion. It would vary depending on the chemistry - Bromide, Iodide, both etc. I would guess they average peak at about 420-450nm - that's purple/blue not really UV which begins from 400nm - -in which case I would need BLUE gel filters not UV lights (or, really cheap UV lights that leak a lot of blue!...or maybe mix n match)

BarryS

6-Oct-2011, 13:22

Jason Greenberg Motamedi

6-Oct-2011, 13:27

Sometime back I read about an experiment using Daguerreotypes (similar color-blind sensitivity as Collodion) in which results from a special Zeiss Planar lens designed for passing UV light were compared to a regular lens. Interestingly the Planar was only negligibly faster than then the regular lens, suggesting that the the UV blocked by glass is not all that important to our exposures.

Sevo

6-Oct-2011, 14:13

I think "UV safe" means no UV-C radiation (the type used for sterilization in hospitals) but it has to have UV light because (back in my clubbing days ;) ) these sorts of lights could make your girlfriend's teeth glow on the dance floor, 50 feet away!

Tooth (and dayglo paint) fluorescence is stimulated by a spectrum range from visible blue to near UV. Even plain blue ultrabright LEDs do it (these deliver no UV at all).

Sevo

6-Oct-2011, 14:25

I would guess they average peak at about 420-450nm - that's purple/blue not really UV which begins from 400nm - -in which case I would need BLUE gel filters not UV lights (or, really cheap UV lights that leak a lot of blue!...or maybe mix n match)

Deep UV might not do much in terms of silver photography - in the print lab at the academy the short-arc UV lit contact frames and process cameras were for screen printing and lithography, whose bichromate gum and azo coats are sensitive in regions of the spectrum far off the visible light.

cosmicexplosion

6-Oct-2011, 14:31

well i think its time to do a test.

cyrus

6-Oct-2011, 14:37

Can you find some studio space with large windows--a loft? Nothing beats the sun for collodion and you don't need quartz windows.

I haven't really looked that hard, tell the truth. Probably. But it would be a hassle to haul everything out of my perfectly good darkroom/studio (which lacks windows - something that was beneficial when it was primarily a darkroom, and artificial lighting was adequate for the studio side!) and take it elsewhere.

In any case my attraction to wet plate was mainly as a stepping stone towards dry plate gelatin. Which, I understand, is not just more convenient, but also faster and sensitive to regular white light. So I may still go the ULF route but concentrate on dry plate instead of wet plate.

BarryS

6-Oct-2011, 14:45

Deep UV might not do much in terms of silver photography - in the print lab at the academy the short-arc UV lit contact frames and process cameras were for screen printing and lithography, whose bichromate gum and azo coats are sensitive in regions of the spectrum far off the visible light.

I use the Fotodiox units for alt process printing as well. They're incredibly fast with gum dichromate prints--maybe 50 seconds exposure. So I think dichromates must be in the near visible UV range. Pt/Pd, VDB, and salt prints are slower, but still pretty fast. Cyanotypes were the slowest of any process I've tried--needing 15-30 minutes with the daylight CFLs.

Joe Smigiel

7-Oct-2011, 17:19

That's fine advice for an LF and smaller camera, but try finding (and paying for) an f/4 or f/5 lens for a 20x24 camera, not to mention have that camera front standard support a 10-20 lb lens! :) (That is where I'm going with this - see if I have a ULF camera built I don't want to be limited to only being able to use it outdoors or next to a window. If I can't find adequate indoor artificial lighting, then such a camera will be a white elephant for me

You're probably correct there. With the money you would spend on a Dallmeyer 8D (if you could find one) you could put in a nice full-room skylight. Either would solve the problem but the skylight is more useful.

In fact we still have to pin down the spectral sensitivity of wet plate collodion. It would vary depending on the chemistry - Bromide, Iodide, both etc. I would guess they average peak at about 420-450nm - that's purple/blue not really UV which begins from 400nm - -in which case I would need BLUE gel filters not UV lights (or, really cheap UV lights that leak a lot of blue!...or maybe mix n match)

Looks like 380nm-420nm is the optimum range for photography with collodion. At about 425nm the spectral sensitivity takes a dive. Here's the spectral sensitivity chart at different ratios of bromide to iodide:

http://www.collodion.com/uploads/54/Collodion_Spectral_Sensitivity.JPG

I'm curious as to why you think wetplate may be a personal prelude or substitute for dryplate. If you are going gelatin, why not film?

cyrus

7-Oct-2011, 17:50

Thank you Joe - this is precisely the sort of reliable info I love this forum for! Can you tell me the source of this chart btw?

This chart would suggest that 420nm aquarium lights (http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=13824) are also a good bet though I don't know how quickly UV falls off and so what distance I could get between the light and the subject

Why not film? I guess partly because I can't rely on film being there in the next 20 years, and anyway it is already hard enough to get for ULF work. And, anyway why not? It is fun. :)

I took my first wetplate workshop back in 2007, occasionally played with it while I also played in photogravure, and am now back to wetplate. But I've never done dry plate before. So, why not? If film dies, I'd be stuck doing photogravure and other contact alt processes with digital, and I REALLLLLLLLY hate digital.

I can't stick with wet plate though. The need to be close to a darkbox/room, and potentially the need for outdoors lighting, is just too restricting. Now if I can cook reliable dryplates that can be used with artificial lighting with the sort of sensitivity that would make normal portraiture practical, that wold be the holy grail.

Joe Smigiel

7-Oct-2011, 20:44

I believe the chart originally came from:

The Journal of Imaging Science and Technology 42:450-458 (1998) The Wet Collodion Process - A Scientific Approach by Skladnikiewitz, Hertel & Schmidt

Joe Smigiel

7-Oct-2011, 21:05

I'm thinking Voltarc AQ-M lamps would be best

http://24.media.tumblr.com/tumblr_lsqbd5u7iq1qmnn9io1_400.jpg

and cheap @ ~$9 each for the F40T12/AQM 48" 65w lamp.

cyrus

7-Oct-2011, 21:21

Thank you now we're getting somewhere! Definitely worth a try! My only concern with this is how far you can get from the light. Lumens are low. Aquarium lights aren't mean to cast a lot of light a long distance.
Funny thing about the price - they range from 9 to over 20 bucks online. What's the deal with that?

cosmicexplosion

8-Oct-2011, 00:03

cant remember, has any one discussed tanning lights, there are some 400 watt ones on ebay that look like they fit into the standard red head type shell.

25 buckaroonies

cyrus

8-Oct-2011, 17:14

BarryS

8-Oct-2011, 18:28

The problem with any sort of fluorescent UV including tanning lights is that the UV drops off at short distances so you can't do any sort of wide shots unless you want to have a photo of your lights too.

The UV wavelengths act no differently than the visible spectrum with respect to the inverse square law. The traditional issue with flo's has been relatively low output spread over long tubes. With high output fixtures or high output bulbs--the issue goes away. The issue you have to watch for is the harshness of the light as the sources are pulled back. How wide of shots would you want to do in a studio?

cosmicexplosion

8-Oct-2011, 19:35

the 400 watt tanning lights referred to looked more like your regular hot lights, ie red head bulbs not flouro

item number 390307048193

10 Tanning Heraeus Face Lamp Replace Phillips HPA 400

Price: US $200.00

if i have a 500w halogen do you think that would blow up a 400w bulb?

cyrus

8-Oct-2011, 20:40

The UV wavelengths act no differently than the visible spectrum with respect to the inverse square law. The traditional issue with flo's has been relatively low output spread over long tubes. With high output fixtures or high output bulbs--the issue goes away. The issue you have to watch for is the harshness of the light as the sources are pulled back. How wide of shots would you want to do in a studio?

Thanks
Most of the anecdotal reports of using flos for collodion say they're using it at something like max 2-3 feet away in order to get a sufficient dose of UV for a 20-30 sec or longer exposure - which is not practical IMHO.

goamules

9-Oct-2011, 05:56

Thanks
Most of the anecdotal reports of using flos for collodion say they're using it at something like max 2-3 feet away in order to get a sufficient dose of UV for a 20-30 sec or longer exposure - which is not practical IMHO.

Cyrus, regarding Fluorescents. Several people here and on the Collodion forum have answered you that they get 5-8 second exposures with fluorescent lighting. Nothing anecdotal about it. That's only about marginally longer than the 2-5 seconds you'd get outdoors. Late in the day, outdoors you may get 20 seconds, outdoors. Wetplate exposure times are different than modern film or digital, but they were practical for several generations. You keep saying there is no discussion on artificial lighting for wetplate, and thay flourescents don't work, while people keep patiently answering you that they do. There is thread after thread on the collodion board about CFLs, Aquarium lights, black lights, including pictures of people's setups. Barry answered above:

... cheap contractor-pack 26w daylight CFLs. With two units, my wet plate exposures are very fast...

The most practical way to shoot wetplate is outdoors or near an open window or skylight. If you are trying to push the ISO 3 of wetplate into something it's not, you're exploring new ground. Wild, potentially uncomfortable, mad scientist lab type lighting is fun to talk about, but no one has done it for a reason.

cyrus

9-Oct-2011, 09:17

Gomules as i mentioned on the colodion firum most of the posts there are if the "i wonder what would happe n if" variety rather than real results, but the few that do present results are not practical IN MY OPINION and only my opinion which i dont cllaim is universal. For example the flo results come from massive lightbank placed to close. Like i said there was one mention of mercury vapor lamps there in the past and im the first to mention specifically mercury vapor UV lamps. took my first coolodiin workshop in 2006 and sibce the ive been playing the mad scientust with lots iof stuff. Thats the fun. Discussing the ootions is the point of this forum. Over at the collodion firum some peoole got their shorts in a knot when i mentioned that using a syringe to dispense collodion eas a workable idea because i guess anything different than how they learned it amounts to blasphemy. Any all of these forums are repetitive and it is the incremental bits of knowledge that add up. Wet plate needs to grt indoors somehow.

eddie

9-Oct-2011, 12:03

i see images on the collodion forum almost daily that are shot with artificial light!?!?!!?

i have seen images taken with about every light source available posted there at on time or another. i have even used a regular" incandescent spot light to add directional light and shadows on some of my scenes a long time ago. to my surprise it worked.

eddie

andy

9-Oct-2011, 19:16

Tracy Storer

9-Oct-2011, 20:16

Sorry not to read the whole thread but...
PLEASE MAKE SURE TO DOUBLE CHECK YOUR UV LIGHT SOURCE IS SAFE FOR YOUR SITTERS EYES !

Apologies if this has been covered...

cyrus

9-Oct-2011, 21:44

check out this light setup by keliy anderson-staley:
http://www.lightwork.org/about/images_about/AIR_KeliyASlrg.jpg

resulting in images like this:
http://www.lightwork.org/exhibitions/anderson-staley.html

Yes and that's wonderful for a head & shoulders shot, but there are something like 40 bulbs there, about 2-3 feet away from the sitter. It is great that that works. But why settle? I'm not saying that it doesn't work, I'm saying that there are potentially other, BETTER options I'd like to investigate and talk about. Wider shots, for example - but applying the inverse square law that would require how many of those bulbs? 100? LOL!

PS: Wonder why the photographer doesn't use reflectors behind those CFLs? And wonder what the speed of the lens was, and what the exposure times were.

cyrus

2-Nov-2011, 21:01

OK so just an update:

I am in the process of testing out various artificial lighting options for collodion and purchased the following:

- 4x105watt cfl bulbs which I will add additional (cheaper! hopefully!) cfls
- an 8 bulb panel of 5ft t5 6500K fluorescent grow lights, 80 watts each =640watts in total
- a 400 watt mercury vapr UV light used for DJ's
- and a 400 watt clear mercury vapor light
I'm going to test out the above, both by themselves and in combination with each other, to see which is more promising. (I don't think any one by itself will have enough power)

Naturally I want to keep the exposure as short as possible not just because of subject movement but also because the collodion starts to dry after 1 min exposure, so I want to keep exposure under 30sec. That's the goal. At f/9 -f/12. (good luck!!!)

For now I'm just interested in seeing what light source will create most response in collodion, and will worry about other issues later.

As for those "other issues" thus far:

The mercury vapor UV bulb is 400 watts but may have an emit peak at 326nm, which is out of the range of collodion sensitivity spectrums ive seen, and one person told me on this forum that lens glass seriously interefers with UV light transfer at 326nm so I'm guessing the clear mercury vapor bulb will be better than the UV bulb? And of course this is potentially a dangerous source of lighting.

The other problem I have seen thus far with the mercury vapor lamp is that the fixture I have is quite heavy (35lbs) and of course is a point source as you all mentioned. So I'll need two units to have more even lighting (not sure what material will "bounce" UV), hanging from the ceiling or something, if I decide to use them. The grow light sellers also sell lighter fixture units with separate ballasts which may resolve the weight problem.

The 5ft flo panels will of course (as you all mentioned) be the most diffuse and even lighting but is large and inconvenient to handle. Not sure how much it weighs as it hasn't been delivered yet. It wasn't very expensive ($200 total, with 8x6500K 80-watt bulbs)

The spiral CFLs: the 105watt 6500K ones are quite expensive at $25-$35 each. I see photos of people's CFL panels whch consists of up to 40 (or more) bulbs - you can't be using the hi-wattage CFLs, are you?

(In order to save collodion I will be coating MF-sized plates on 2mm glass which I was lucky enough to find. Ultimately I want to make wetplate negs with these which I can put in my enlarger.)

DanK

3-Nov-2011, 00:10

eddie

3-Nov-2011, 04:29

but also because the collodion starts to dry after 1 min exposure,

that is not true.

rob kendrick has done a few shots that took over 30 min from flowing the plates to developing them.

i have also shot over 1 min on many occassions and have not had the collodion dry out on me.

just for the record....collodion starts to dry as soon as you pour it on the plate...starting to dry is not an issue. drying out is the issue.

eddie

ps, buy faster lenses already.....you will probably end up with the same money spent after you buy all them lights......

Fourtoes

3-Nov-2011, 05:52

For what its worth my last exposure for wet plate was 12 minutes.......

cyrus

3-Nov-2011, 08:29

that is not true.
ps, buy faster lenses already.....you will probably end up with the same money spent after you buy all them lights......

Faster lens for a 20x24 camera, open to suggestions.
(I am actually experimenting with Wet plate ULF as a stepping-stone to dryplate and hoping that dry plate will prove to need less fancy lighting)

cyrus

3-Nov-2011, 08:34

Cyrus,

I've noticed a few posts where you mention dry plate as an alternative...

I have no experience with wet plate, but with dry plate here's my experience...

I had a small studio (15x25 +-) and thought I'd add dry plate portraits (liquid emulsion tintypes) - it had no outside light sources - dark - spent some time experimenting with lighting - trying to find something fast enough for a simple seated child portrait.

My studio strobes, which weren't much, but plenty for the studio size for film - all mono's - 2 320w/s - 2 160w/s - 2 100w/s...wouldn't touch dry plates...I tried a half dozen quartz...hot, still slow...Tried half dozen hot lights with daylight 500watt bulbs...still hot, still slow...tried 4 - 4 light 4' daylight flourescent banks with an 8 light 4' flourescent ring...got down to 3-6 seconds w/ f4 lenses...but still slow and they had to be very close, too close for normal crops...

I never tried HID lamps, and finally dropped the idea - figured the best route would be actual daylight...

I wish you luck...and would like to know if you find something that actually works...

Cheers,
Dan

Ach! Thank you but this is not good news!!! :( What formula did you use to make your emulsion? or did you purchase Liquid Emulsion?

Silver is silver, whether in collodion or gelatin, and needs close to UV exposure but I am hoping that the "ripening" of a homemade gelatin emulsion would provide more sensitivity than wet plate. (In fact I am depending on this! when film is no longer made.)

I would want to test with continuous ligthing of course but if I can't do dry plate with less exposure than required for wet plate, I'm not going to go ULF at all and will spend the $ on an nice etching press for photogravure instead. (I'll probably just keep my 11x14 camera for the occasional use outdoors but mainly as a dry plate camera since doing LF wet plate outdoors is just too incovenient for me)

johnielvis

3-Nov-2011, 18:49

HEY===there's some dude on collodion that can FREEZE motion on wetplate with TWO 1600 ws strobes at 5'

now...all my monolites are 750's...3 of them...3 more and I'll be in bidness....

this is what I calculated from my experiments using paper in the camera with strobe

must be at least double what I got....even then...wide open, you know?

Sevo

4-Nov-2011, 01:56

Getting hold of flash tubes without UV blocking "gold" coating is probably half the way to success...

johnielvis

4-Nov-2011, 04:07

ahhhhh....yeah....I noticed that last time I was looking at strobes...I got some that are like 13 years old and at that time they didn't mention anything about uv coating---NOW i I want a replacement tube, it will likely have to be the upgraded type

so is that how you tell? a gold coating? mine are clear and I can't remember any sort of gold tone last time I saw new strobes....not that I was really looking, but nothing on the tubes seemed to look overly ANY color other than like BLUE...

yeah--that's tough--how to determine the uv output BEFORE you buy replacement tubes or new strobes--it's not like there's uv flash meters available...

cyrus

4-Nov-2011, 08:41

Getting hold of flash tubes without UV blocking "gold" coating is probably half the way to success...

Ah, yes. That's a good point.

cyrus

4-Nov-2011, 08:43

I forgot to add that I've discovered there are such things as 250 watt 6500K flo grow lights made by a company called Feliz. These are sort of expensive at $70-$100/bulb but should provide quite a punch! I had been a bit reluctant to bother with CFLs until I noticed these.

Scott Davis

4-Nov-2011, 12:50

Salted collodion is sensitive over a range from blue through near UV wavelengths. Glass still transmits a good proportion of UV--especially in the range of collodion's sensitivity. I'd love to test a Kalosat lens with quartz elements to see the difference in exposure--but they're sort of...scarce. :) I still have to take Scott up on his offer to test out his non-uv coated flashtubes. There's theory--and then there's practice. Can you find some studio space with large windows--a loft? Nothing beats the sun for collodion and you don't need quartz windows.

Barry- I also saw in your earlier post you have Hensel strobes. Not sure which model you have, but IIRC, there are uncoated flash tubes available for Hensels as well. Probably not worth the ~$300 per tube as an experiment, but we should try it out with mine (Calumet/Bowens) and see if it works. If it does, you're 3/4 of the way there, and just need the spare flash tubes. Oh, and I now have TWO 2400 w/s packs, so they could be daisy-chained together if one pack alone is insufficient. I don't know if I'd try it at my current studio though - the wiring is definitely sub-optimal.

Another thought, to the general audience- some strobe manufacturers deal with the uv-blocking by coating the glass protective domes and leave the tubes alone. If you have a glass protective dome on your strobe, you could always try and take it off.

jnantz

4-Nov-2011, 13:23

Faster lens for a 20x24 camera, open to suggestions.
(I am actually experimenting with Wet plate ULF as a stepping-stone to dryplate and hoping that dry plate will prove to need less fancy lighting)

i have done dry plate work since the mid 1980s and found it to be
a piece of cake compared to the things i am learning / have learned about wet plate.
the only similarity between the two is using glass as a substrate,
unless you make dry collodion plates ...

good luck !
john

cyrus

4-Nov-2011, 14:15

i have done dry plate work since the mid 1980s and found it to be
a piece of cake compared to the things i am learning / have learned about wet plate.
the only similarity between the two is using glass as a substrate,
unless you make dry collodion plates ...

good luck !
john

Would luv to hear / see more about how you do this, John

jnantz

4-Nov-2011, 15:43

hi cyrus

i've dabbled with making my own emulsions, but it was easier to make+use
bottled emulsion in the end ( bottle of liquid light cost less than making it, and i was a broke student ).

i have made dry plates just like Mark Pedersen describes in the dry plate
page on alternativphotography . com it is pretty easy.
the hardest part is cleaning the glass. i use a foam brush, nothing fancy to coat
and while some may cringe ... it has worked fine for me ...

http://www.alternativephotography.com/wp/processes/gelatin-silver/silver-gelatin-dry-plate-process

i've coated upto 11x14 plates with good success and tiny ones that i enlarged from
and coated bigger ones ( greenhouse glazing ) that i enlarged onto, and then contact printed ...

i don't have many of those images scanned or rephotographed &c, and some of them
shattered into a million pieces, so i really can't show
you many examples of what i have done, but i can say it is a lot of fun and kind of addictive :)

these days, the best resource is probably the lightfarm.com
there are lots of experienced people, way more experienced and knowledgeable than me at the light farm ...
and they can show you examples of what they have done ...

cyrus

4-Nov-2011, 16:47

Cool what kind of lighting were you using and how long were the exposures roughly? Im trying to figure out if this is practical enough for i.door ulf.

jnantz

4-Nov-2011, 17:30

i was using natural light
and rated the emulsion at
about asa 1-5 depending on the light
and it was like a slowish photo paper when i projected onto it.

they say if you put a blue filter
over your meter you will get a sort-of accurate meter reading.

before you do it ULF you should do small glass
to make sure you won't have trouble.
if you don't sub the glass right, the emulsion lifts off and puckers.
but it can give interesting results just the same.

good luck !
john

cyrus

4-Nov-2011, 19:38

before you do it ULF you should do small glass
to make sure you won't have trouble.

That's what I'm doing indeed. I have experience with wet plate on and off for a few years mostly as a curiosity and then I tried dry plate gelatin a couple of times and noticed there were some similarities (in coating plate etc.) so I am back experimenting with it all but more seriously this time, to see which is most practical esp indoors with artificial lights.

johnielvis

5-Nov-2011, 01:58

hey---howz about olde arc type lights? anybody every try somethign like that---THEM ought to be hot enough...them old projector lights or what they used for movies back in the day when they had those very slow films?

I bet that's like the best to use if you can somehow adapt it to household outlets......maybe some kind of adapted arc welder????

I was thinking of getting an old theatre projector--them older ones used arc light...

I just checked---there'ssome 16mm projectors that use arc BULBS!!!! super brite! they say...there are replacements...THIS is where we should be looking---arc has GOT to be WAY hotter-uv than anything else out there.....

here's from the knowledgebase of wikipedia:

Xenon-mercury short-arc lamps have a bluish-white spectrum and extremely high UV output. These lamps are used primarily for UV curing applications, sterilizing objects, and generating ozone.

cat3261

21-Jan-2014, 18:57

I know this is old post but I am getting incredible results withn2 speedotron quad heads, 1 4800 watt head and 2 2400 watt heads, about 30,000 watts, you get real control, if you are going for sharp you can count the treads on all the clothes

C. D. Keth

22-Jan-2014, 10:58

jnantz

22-Jan-2014, 12:59

hi again cyrus

not sure if you are still doing this project or not , olde thread resurected and all that...
seeing liquid emulsion/dry plates are blue sensitive ( and oldish liquid ligt gets faster with age from my experience ) it seems that blue lit/ tungston bulbs migh work ok .. i havent tried H2O2 steaming the finished plates
but allegedly it is an olde astrogrhers' trick to "hyper" the speed of the emulsion
(works with film at least) maybe if your plates are excessively slow ...
bulb,an/grey supply might have some ideas for filament bulbs so you dont have to have your sitter sign a waiver (blindness). massive light and uv probably isnt a good thing to
expose ones eyes to, thats why i just use full spectrum ( neodymium?) and the modeling bulbs in my monoblocks that i use when not doing available light -stuff...
ive made a ton of studio portraits with paper negatives and it seems to be the same stuff, maybe a stop or so slower?
i never hypered anything or used massive light output, just had my sitter/s sit still for a long time ...
good luck with your mamouth plates! i have been coating 8x10s again, metal too, but without a sub layer
and no worries of emulsion lift.or puckering. you need a very cold flat surface post-pour for shovelled gelatin to set
and as much as i hate the stuff .. hardened fixer.

john