[Bingtan]

I’m from the Philippines and have been doing my test plates on 4x5s for the last 3 weekends. It’s the most conducive time for a tropical country as humidity is down to what’s good for dag making…so yea, contemporary dags silently working hard in the outskirts of Asia…

[Bingtan]

hi guys,

thank you. actually just felt bad that I will be releasing the air into the environment without any sort of filtering so had wanted to at least use some for of media before releasing it out to the air.

[Bingtan]

If humidity is high inside the box, the silica gel will keep absorbing water – competing with the I and Br inside. The only way to release the water inside the gel is to heat it but when that happens, I and Br also gets released, or even before that…

According to photolytic, by putting CaO, it can act as the H2O replacement dessicant instead of the Silica beads thereby keeping your beads busy in just absorbing I and Br. CaO only attracts I and Br when they are in HI and HBr form.

If the silica beads are heavily saturated by H2O already, I don’t think the CaO can do much about it..

[Bingtan]

Andy,

it seems like CaO will pull water from the fume box > including the water contained inside the silica gels (aside from I and Br).

When the CaO gets saturated, that is what you heat to dissipate the water absorb by the powder.

So it seems like CaO is acting like the dessicant of the dessicant (silica gel).

[Bingtan]

Andy,

it seems like CaO will pull water from the fume box > including the water contained inside the silica gels (aside from I and Br).

When the CaO gets saturated, that is what you heat to dissipate the water absorb by the powder.

[Bingtan]

Photolytic,

That is incredible information for me which will be extremely helpful for my more humid environment. I will take that advice and bring in some slake into my fuming boxes. May I ask for a nice ratio/proportion? I use those “standard” 11-cup pyrex trays a lot of people seem to be using. How much calcium oxide:h2o -> calcium hydroxide should I introduce as a starting point? say 200grams CaO + 40ml H2O?

Also, If the slake acts as a “dehumidifier”, is there any reason to take it out of the fuming box? Why not just leave it inside the box?

Nwg,

I’m slightly confused in that, not all Br fuming actually shows a color change. So I was under the assumption that I may have really have to nail down a time…which obviously makes things a lot more difficult. Ok, I shall try to see the color changes in Br given your suggestion. I’m hoping I see it as distinctly…bec honestly, I couldn’t see the change in color of Br on my plates. Iodine, I can. It’s very distinct.

[Bingtan]

Hi photolytic,

On my notes, our current humidity is around 41% when I was fuming

1) Slake lime is calcium hydroxide (just making sure)
2) Correct me if I’m wrong but slake lime is placed inside the fuming box when you don’t have any iodine or bromine in the box to take out the moisture?
3) I don’t take out the silica beads (I & Br) in my fuming box. Is slake lime something I can introduce into a box with I & Br Beads to help take out the moisture? The slake lime is introduced in the box to take out the humidity? Won’t it absorb both the I and Br or only just water?

Bing

[Bingtan]

Andy, don’t be silly, being new, I am trying to understand things as fast as I can on top of which, you guys would be smarter at asking the right questions which I may not understand. Can you share w me how you use slake lime? An idea of proportions including rough size of the container it’s held in?

By the way, just call me Bing 🙂

[Bingtan]

wow…that is a lot of science into fuming…so yesterday, I did some practice. One of the things I realized is that a 6×6 plate is quite small compared to the size of my box which is good enough for an 8×10. As I did multiple fumings trying to test things out. 500gms of deeply “soaked” iodine silica beads is a lot, making fuming times really fast. so right now,

My box is lowered to just about 100 grams of iodine silica beads giving me about 20-25 secs for first yellow. Any longer and I start seeing reds which quickly goes into blue at around 40 secs.

For bromine, I lowered it from 500 grams to 250grams. I think it is now at the right color/dilution of light yellow beads. I will start fuming again next week, getting a grasp for all of these things.

The iodine part, sure I understand it needs practice but it’s quite visual. It’s the bromine that I’m worried about because I can’t judge it visually but by time. I think this is where I’m going to need a lot more practice. Since I’m practicing heavily by rotating some 6×6 plates, I will be working on Nawagi’s Bromine fuming suggestion of a 10-20-40-80secs in 2 plates.
Bing

[Bingtan]

Thank you Nawagi / Jason,

seems to be the case. can I ask a stupid question, now that I’m getting to understand that the Bromine phase is such a critical step, bec it’s a phase that may not be visible to the naked eye but more of a time-based approach – is there a possibility in using a sensor to make it easier for practitioners to at least get insight if the bromine is too strong? I came across this manual detector that can detect up to 20ppm?

http://www.zefon.com/store/sensidyne-114-bromine-detector-tube.html

I mean in the long haul, at least you can tell if your beads are already exhausted (since I noticed that you really just need a very small amount of bromine apparently!)

[Bingtan]

has anyone considered using LED spotlights? I currently have an Arri L7-C – it’s an LED fresnel spot that is color tuneable from 2,700 to 10,000K

The lack of heat makes it quite good for the subject. I had a reading of about 8.2 ev at about 18 inches.

I reckon if you had 2-3 of those, it could work?

I’ve been using it for large format photography.

Here’s some info and here’s the light from bhphoto:

http://www.bhphotovideo.com/c/product/812828-REG/Arri_553500C_L7_C_Color_LED_Fresnel.html

[Bingtan]

Nawagi,

thank you so much for that response. I will take all of that advice to heart. Right now, I spent the week properly “calibrating” and learning my fuming. So it seems like Iodine, I’ve lessened the chemicals to give me a good enough start for golden yellow to a tints of rose – I’m hitting between 20-25 secs. 20 is golden yellow. 25 it starts having some tints of rose.

It’s my Bromine that I’m still having a hard time at the moment. I’ve diluted it to something far less strong and I’m hitting somewhere at 1:30 minutes to 2:15 minutes where I get the nice even magenta.

It’s slow paced but it’s getting there…

Thank you for now and will keep you posted with the next plate I make…

Sincerely,

Bing

[Bingtan]

Thank you nwg…i feel the road is going to be long and winding but it’s going to be so incredible if I’d get to pull this off…would you mind sharing tips on how to improve the image quality?

[Bingtan]

Hi,

can someone help me reach Alan? been wanting to purchase a mercury pot from him. my email is sombreroisland@gmail.com

Thank you,

Bing

[Bingtan]

long day again…I was able to make a few plates but must say I’m still far off…here’s some details:

1) Weather temp – 35C
2) Mercury temp – 80C / 2 mins.
3) Iodine silica gel – 60 secs.
4) Bromine silica gel – 20 secs.
5) 2nd Iodine – 15 secs.

I tried doing some color inspection on a second plate but I when I started noticing the pink on 1st I, it took too long – 2 mins. Br was 30 secs. I went through the whole process again and the image was lighter – I think now I know the limit of when I went too far.

So I tested a plate outside of my tent and it seems like I get my first light pink at 40 secs. I will have to give this a go again tomorrow. The speed of fuming I assume would be highly related to my working temp – it’s just far warmer where I’m at. So my next experiment would be to go for:

1) I – 40 secs.
2) Br – 15 secs.
3) I – 20 secs.

I have a few questions regarding today’s plate:

1) When you’re looking straight at the image, it’s all bluish…I wonder if it’s under development? ( 80C at 2mins)
2) I’m just curious- I’ve never seen a real dag plate up close and I’m looking at everyone’s pictures and I see blacks. Is there really suppose to be any black? My images are primarily a thin layer of powdery white. I mean, if I’m shooting for black, it looks like I’m a long ways out! I tried purchasing one on ebay before but a seller sent me a tintype instead of a dag.
3) anyone got a properly expose plate they’re willing to let go off that I can buy? So at least I’ll have something to work my way towards.

Thank you for your advice. I must say, this is driving me nuts and today, I am starting to question the sanity of all this. It’s not easy…but I’m too far in to give up at this point!

Sincerely,

Bing

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[Bingtan]

Hi John / Mike,

Thank you for the very fast response. Other details:

1) Weather temp – 35C
2) Mercury temp – 80C / 2 mins.
3) Iodine silica gel – very dark to black
4) Bromine silica gel – very orange. I know from another thread that Mike suggested it be light yellow but I didn’t have any other container right now to manage the bromine. That said, I’m assuming this is stronger so should give me a working idea.
5) Light meter reading was sunny afternoon sun – ISO 3 / f/2.8 / 1/250
6) My pot is good to fit a whole plate so it’s pretty big for a 6×6 but it really doesn’t seem like mercury is the problem…

Mike, the image is indeed that, very pale. The reason I assumed my coating was the problem because I made another exposure at 8 mins – both this and the 2nd image came out exactly the same.

Iodine at 3 mins was quite deep red. Bromine was pushing to about purple. Admittedly I wasn’t checking the Iodine color on the plate inside my “darkroom tent” for worry of fogging. I had based my 3 mins. while I was outside the tent making a test plate.

I will give this a try cutting fuming to the following:

Iodine – 60 secs.
Bromine – 20 secs.
2nd Iodine – 15 secs.
Exposure (given the same light quality) – from 30 secs to 4 secs.( 3 stops less ).

I guess my situation being in the tropics is very different from a lot of people’s experiences so I just wanted an initial point of reference. I will try fuming and exposing tomorrow and I’m keeping my fingers and toes crossed!

Thank you!!!

[Bingtan]

Hi Blake!

I haven’t been here at cdags for awhile, working on the rest of my equipment. I can’t offer a good update on the box as I only started fuming now.

That said I saw that you had your box done already but if it’s still relevant, the teflon on my box are all fit together and seem to be doing ok. Essentially, I made a smaller, inner teflon box from 1/4″ material which I routered 1/8″ on each edge and then sealed. so far so good…

Bing

[Bingtan]

sorry here are the attachments

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[Bingtan]

these boxes are finally done and they really. REALLY. drove me nuts. I don’t have a future doing this as my day job… I still have to make handles for my slide but at least I can fume w these already.

Pyrex trays were polished flat pressed against 5mm of teflon sheet.
Whole box is teflon lined.
Viton rubber for slide compression. I have a glass piece from the top of the viton slide with dried silicon bead at the center to make further compression in the center of the box.

[Bingtan]

Against people saying I shouldn’t do it, I actually synthesized bromine from bleach and sodium bromide…I think I got about 20ml fairly easily. I’ll be doing another batch again soon actually.

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[Bingtan]

Hi John,

Thank you for those insights! I think my work is not yet done! I was wondering, I actually don’t intend to store the br and i in the box. Just during fuming…that said though, I was intending to prop up the Pyrex and push the top down with viton sheets. Would that be good enough?

Too late for the Teflon unfortunately 🙁 I don’t think I could afford another one right now. I’m banking on the viton to act as the seal in between the layers.

Thank you for indulging me!

[Bingtan]

Hi Andy,

as requested, here are some detailed shots.

Photo: Shows pyrex inside the box. I just got a pair from amazon. I think that’s the 11 cup. size. Rulers placed, the length is less than a foot. Width about, 9 inches (that steel ruler is 6inches). The area where the pyrex is will still be wrapped in 1/16 viton sheet.

Photo_1: Is a pure teflon sheet 6mm which I’ve drilled off the center. The rounded pyrex still needs to be polished flat so the teflon is flushed against the tray.

Photo_2: I’ve made a plywood sandwich just so I get more surface area to help whatever fumes escape. 1/4″ plywood. The 1/8th ply will actually be the holder of the plate. That one will be removeable, sliding in and out.

Photo_3: That’s how the wood sandwich all looks like.

Photo_4: I still haven’t glued one side.

Photo_6: There’s a 1/4th slot there. still working on the handles for that slider so the fumes don’t escape.

Hope these few pictures help clear things up…again, this was my first and only attempt at wood working so I can’t say I’ve done the most secure. I know using plywood would be best, I guess I just wanted to do something nice for myself.

For those with experience, may I ask, will bromine/iodine eat through wood glue and super glue?

Sincerely,

Bing

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[Bingtan]

I use pyrex labware with a PTFE Stopper which I got from ebay – and it’s painfully expensive for something so small :

http://www.ebay.com/itm/STOPPER-Safe-Lab-Extraction-Teflon-PTFE-45-50-NEW-Lab-Safety-/400215862631?pt=LH_DefaultDomain_0&hash=item5d2eb96d67#ht_1537wt_1210

I then immerse the whole bottle in silica beads, inside a jar…

I once had pure bromine in a brown bottle, using only a teflon-lined plastic cap – it was eaten in days. The link above is pure teflon.

[Bingtan]

I made a quick check on Amazon and they had the 9 micron grade 1200. are these the right finishing sheets?

Thank you again.

[Bingtan]

thank you for tips. I was basing my steps from the posts on the board and I got confused.

1) I was going through the net and I had thought mineral spirits was the same as denatured alcohol. I made that wrong assumption.

2) ok on the RO setting…

3) May I ask what grade the micro finishing sheets are?

On another note, I actually just made an electrolyte for galvanizing, wanted to ask, is the sodium thiosulfate solution that contains the AgCl light sensitive? I placed in a black bottle. Is the galvanizing step light sensitive too or is it something that can be done inside the house w fluorescents on?

I’m assuming that the sky blue is done by inspection but more or less how long does it take?

Thank you so much. Feels like I just jumped into the deep end of the pool…

Bing

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