The Film Developing Process Step-By-Step
So now, we're gonna come in here and we're gonna do the development. This tank holds approximately 500 milliliters. I switched a number of years ago to the metric system for my photography. To say that I'm math-challenged is an understatement. When you've actually watched me meter, you'll see me be like six stops, okay? Ounces, and then there was like European fluid ounces, and then I was like, milliliters, I can divide by 10 pretty well, so I use the metric system. If I wanna measure it's about 16 ounces. Some tanks will have eight, some will be 32 ounces, 1,000 milliliters. But basically what I've done is I've got all my chemistry set-up. We have the developer, stop, fix, this is the wash, this will be the second wash, this is gonna be my pre-wash in a second. Doug's gonna continue to cycle this and I'm gonna get all the chemistry poured out up front. I don't wanna deal with the big gallon jugs, I don't want do that, I want all the right amount of chemistry set up front. The other th...
ing that's important is most developers are set for 68 degrees. When you read how long to develop what the temperature should be, it's 68 degrees Celsius about 20 degrees Fahrenheit. The rest of the chemistry needs to be within three to four degrees, maybe five of that. If not it can shock the film and I've watched films shatter, it doesn't actually shatter but it breaks like safety glass. I've seen it melt the emotion off because the temperature was too hot. Everything needs to be relatively the same temperature. What's great is in your house, if you're not like in a garage where it's frozen in the winter, your house is somewhere around 68, 70 degrees, in an area, like if you've got a basement or whatever, store your chemistry there if you can then it's gonna be pretty close. If the chemistry's too hot or too cold, you can use a water bath or a hot bath. Basically you would take a tub if it was too hot, fill the tub with ice water, stick this in there, and then it cools down from the ice water, when it hits 68 degrees you'd pull it out. We get the chemistry little, you'll see that I have little labels on all of these. I go in the same order every time, it's always the same process. The reason these are labeled is I don't wanna inadvertently have done a bad job washing and run a higher risk of cross contamination. So I know my developer, no matter what one I use, is always in this jug, always in this one, and always in this one. Okay, I loaded the film, and then I'm wanna put on my safety glasses because I'm about to play with the chemistry. What ultimately matters probably more than anything in the overall process is the consistency. Everything needs to be the same, development to development, because if you're the developer longer times, if your the developer shorter times, if you only agitate sometimes, you don't agitate other times. All those variables just make it more difficult to control the process. At the end of the day, like I said, When I want a negative that's gonna give me the best opportunity to work with my print. As I'm working through I'm all excited, everything's cool, I'm ready to get going. The first thing I do is a pre-wash. The pre-wash is just water. Plain distilled water, filtered water. When you're working with the metal tank, you gotta hold it at an angle, because if you hold it like this it develops air bubbles and the chemistry can't pour in. That's why the big plastic ones the fast easy pour. You just hold it at about a 45 degree angle. Then you're just gonna pour the water in. As long as you're at that angle it's just gonna pour in just fine into the lid, and you'll feel it start to fill up. As it starts to fill, you just give it a gentle little twist, and I've got my pre-wash in there. Okay, next thing I'm gonna do is I'm gonna tap the tank a few times. (tapping sound) To release the air bubbles. Air bubbles will sit there and that'll keep the film from getting wet. I'm gonna add some more water to that in a minute. Then I'm gonna agitate this. This agitation pattern right here, is the one I'm gonna do pretty much every single time. Agitation in all of these is about moving new chemistry on to the film. That agitation, and then I'm a hit the table and I gave it a quarter turn. That then moves the developer around this way in addition to this way. Because I just have water in here I'm gonna show you what not to do, none of this, okay, none of this, none of this, okay. We want nice simple agitation because the thing agitation is doing, is it is causing the developer to move quicker, which is causing the development of the highlights to happen stronger. I lose the control, now it will also accentuate grain. Some people are like "Well I really want grainy stuff". Let's deal with that, by the length of the developer, changing developer, because you're not gonna remember any of those dance moves to Katy Perry you did while it was on the radio okay. So just a nice simple, it's about two to three inversions in five seconds, okay. Well actually give me that back because I just realized what I wanna show them. (chuckles) Okay so this has been in there for about a minute. The reason I like the pre-wash is it soaks the film so that it more readily takes the developer all at once. So I get a more even consistent development. It's not required. You can go straight to the developer. If though you pre-wash, you wanna always pre-wash. If you pre-wash and then go to the developer and then next time use a pre-wash, your development results are gonna be inconsistent. The reason I also wanted to pre-wash is I wanted to show you this, don't freak out. That looks terrible, and you're like something went wrong. Nothing went wrong. I mentioned it early on that film has an anti-halation layer. That anti-halation layer helps as light comes through the film, hits the back of the film base, it could reflect back up and cause some exposure issues in the silver. The anti-halation layer absorbs that. This is the anti-halation layer washing off the film. It would have come out in the developer in the other ones anyway, so it's gonna come off, but don't freak out when you see that happen. Okay, the next one is I'm in the developer, so we're getting ready to move to the developer. The developer's job is to basically take silver halide which has been exposed to light, and turn it into a silver metal. The silver metal then becomes the photographic image. Every developer is a little bit different, and every developer is gonna have a different time. You figure that out by figuring out what is the right amount of development to get that zone seven, in a normal exposure. I'm gonna develop so that zone seven looks correctly. We'll talk about that later today exactly what that means, but we're looking to get a five stop range of what zone seven looks like. The developer we're using today is D-76. D-76 is the classic Kodak developer, it's been around over a hundred years now. It was originally used for film development as well, like Cinema motion picture development. It is the standard by which all other developers in some way get measured. It's got some really cool properties we're gonna talk about in a second. It is diluted at one to one. What that means is it's one part stock D-76 developer, and one part water. If the dilution was one to three, that means one part stock D-76, three parts water. If you're using a developer like Rodinal, or RO9, which is another film developer, it dilutes it one to a hundred, or one to 50. That's one part developer to a hundred parts water, so the first number in the number colon number, is the amount of developer. Sometimes when you get started it's easy to flip that and you think to yourself, well there's no way, Rodinal is like one to a hundred, there's no way it's one ounce of developer to a hundred ounces of water, it's that concentrated. It's always the first number. The time for this case for Tri-X at ISO 200, and D-76 one to one, done enough testing that 10 minutes is our time for development. What's gonna happen is I'm gonna pour the developer in, and then we're gonna agitate for the first minute. That agitation in the first minute is really important because that's starting to get all the developer around all of the film, and start to activate all of those zones and we wanna get a bunch of stuff to happen early on because the shadows are gonna develop, and they're gonna eventually gonna peter out. Highlights are gonna develop, so we wanna give everybody just this big hit of energy as they do it. After that, after the first minute's done, I'm gonna agitate every 30 seconds. I'm gonna do about two to three inversions every 30 seconds until the process is done. Now like I said consistency is key here, so what I'm gonna do is, for me, I pour the developer in, and I start the clock. Then when the clock stops, I pour the developer out. Now you might be a person who's like, well I start the clock and pour the developer, and then when the clock stops I do this. Or you might be a person who's like nawl I do this. All that matters is you do the same every time, consistency. Doesn't matter because you start to flux with the time and move things around, as long as you're consistent you can repeat it again. Okay, so I have the clock, it's all set up here. It's just gonna go around and around, counts down from 10. You can use your iPhone timer, whatever you want to get going. I grab my developer, I remember which button turns the clock on. Then I'm gonna pour the developer in. You don't wanna freak out if a little spills over the side that's fine, you're just gonna get that developer poured in to there. Comes over the top, that's fine. We're gonna get the top on. Turn the timer on. I give it a little rap to get rid of those bubbles. Then I start my agitation, okay. Now I'm going for a minute here, so I will occasionally, you'll see me give it a little spin. Watch my fingers I give it a little spin. I've got huge hands. If you've got smaller hands you can just take two and just, two hands to hold on to the tank. You can switch hands at this point. It's just a nice rhythmic motion like this. All I'm trying to do at this point is move the developer across the various elements of the film. To get that initial 10 minute time, people wanna know, if I pick a developer and I choose a time, there's a website called The Digital Truth. They make a chart called the Massive Development Chart. They also make an awesome app. In the bonus materials I have information about how to use it, but that's a good place to start. The film data sheets I told you about, they also have information about developers and what to use. What they won't have is strange developers, or developers that aren't their own. Alright one minute, down, quarter turn. Ilford films will have the Ilford developers, Kodak films will have the Kodak developers, and vice versa. Once you pick a developer and if it's giving you what you want out of the film in terms of the characteristics of grain, speed, contrast and things like that, there's no reason to flux around with a hundred different developers. You can spend a lifetime playing with this, pick a good one and you're all set to go. Dark room towel, hands a little wet. Dark room towel's good. Kind of clean off the top a little bit if you want. Clean up my little mess. So I'm at 30 seconds, I'm gonna go ahead with the agitation now I was two seconds off. I don't panic, I don't freak out, everything's good. In the developer world, there's a couple of types of developers. Well, I'm sorry, there's a couple categories of developers. We have solvent developers and non-solvent developers. Solvent developers are all about finer grain. Non-solvent developers are about acuteness or sharpness. Some developers in both categories are also what they call speed increasing, and some are what we call speed decreasing. Now, I know what you're thinking, you're thinking I want speed. Just speed increasing developer and then I can process at 12,800. No, we're talking about maybe a half stop maybe a stop. You're not gonna get a huge change. The solvent developers are fine grain because their goal is to minimize the impact of the grain on an image and they do that a couple different ways. The developer that's actually in there, has the ability to re-plate some of the silvers. So it can pull some of the silver off and re-plate it to help minimize the grain. That's one of the things it does, and it's also not as aggressive on the edges of the grain. As it's working through it's process, it's able to say oh don't accentuate and make the edges really sharp. The non-solvent developers will make the edges a lot sharper so you end up with a lot more punch to that. On a large format camera, the non-solvent developers are great because you get the sharp edges but you have so much more data in the information of the film, that you still preserve the beautiful gradations you might potentially get with a solvent developer. Those are your two big categories. Inside of there, the other interesting piece, is some film developers will be something different based on the dilution. D-76 is a great example. It's a solvent developer at stock at one to one, but it exhibits the properties of a non-solvent at one to three. In the bonus material I cover a little bit of that, I have a chart for you that kind of helps accentuate that. If you're starting out, there's a couple of other things from an environmental standpoint, XTOL is a wonderful developer made by Kodak that's actually, it's core element of the developers of vitamin C, absorbic acid based piece, it's pretty good. D-76 is pretty good. The most toxic of the film developers are film developers that are pyrogallic acid based. Which sounds really scary. It's one of the more toxic of the developers but it's highly dilute. It's a really beautiful, it's called a Tanning developer, so it basically gives you really super sharpness, but then it stains the film to give you the gradation, so you kind of get the best of both worlds. It's it's unique beast onto it's own. But if you're getting started, I recommend you start off with XTOL, D-76. Ilford makes something called ID which is basically their version of D-76. Those are bulletproof, millions of people have used them. hundreds of millions of people have used them. Labs still use it, a lot of labs still process and develop in D-76 so everything is good there, a great piece. You were a D-76 guy right? And then you're switching.
Moving, I'm trying the XTOL these days.
What's causing you to change?
Well I like the environmental aspect a lil bit, but also I think I can maybe pull a bit more out of it.
Yeah, so each film has the ability to change the dynamic of the grain of the image, and how those tones develop, so there's a subtle shift in trying out different developers so what'll happen is you'll see something you're filming, usually you'll see someone else's photograph that'll have a characteristic you like. If you dig a little bit, if they're a film person, they'll tell you what developer they use, what film they use, and that can point you in a different direction. My default developer is a developer from Kodak called HC-110. It was originally developed, it's a non-solvent developer, and it exhibits some really wickedly interesting characteristics in terms of how it can expand and contract the zones to the development. There's a way to use that as a pretty heavily manipulatable developer. I don't wanna flux around with a thousand different developers, so once I learned that HC-110 worked for me and the things I did, it was HC-110 or D-76 for me. I used XTOL for years and years and years, and then I have a very special application for XTOL that I used with a certain film sometimes, but for the most part that's what I used. It also makes my darkroom a lot easier, I don't have 16 bottles laying around. I aint gotta like, oh when was the last time I used that, I don't have any of those kind of problems. Okay a couple other things about developers and their characteristics, there's the actual developing agent, and then there's also in there a couple of other things that help the developer work. There's a restraining agent in there, because we don't want the developer to just go absolutely crazy on the film because the highlights are just gonna take off and run. Cause the longer it's in the developer, the more the highlights develop. We also don't want it to aggressively get after micro contrast and things like that, so there's a restrainer in there that helps pull it back. Each of these is nothing but a set of chemicals. The other piece you can do is you can start to look at some of the history of photography, and look at what chemistry is involved there. You can actually mix up your own D-76. You can buy the chemicals and you can say, oh I'm interested in less of a restrainer or more of a restrainer. You can customize the feel and the experience of the developer a little bit. I have some historical processes where I mix up my own developers to work with, but for the most part I just go on ahead and use the standard piece there. The other interesting piece about working with the developer is time is a big factor in using them, and the more dilute they get the longer the time will happen. so one of the other things that I would encourage you to do is, don't sacrifice the feel of the image because of how long you have to develop. If I took D-76 at one to three, my development time is gonna slide to probably around 17 minutes. If that's the aesthetic I want, don't be like oh well I don't wanna stand here and do that stupid upside down thing for 18 minutes. It's really about the aesthetic and quality you want. There's a development process I use. It's a variation of what's called Stand development. Stand development is we take an extremely dilute developer, and we put it in the jug and we rarely agitate, and it might take hours for it to actually develop, and the reason we do that is the highlights and the shadows had such an extreme ratio, what I need to do is help the shadows develop as much as possible and restrain what the highlight's doing. As the developed gets dilute, if it has the right restrainer and chemical properties, it'll actually build surface tension onto the film. As the highlights develop, they exhaust the developer. They're in surface tension builds, but because there's not enough latent silver available in the shadows the developer can't build the surface tension the developer gets to continue to build shadow detail. It allows me in the case of like, oh my gosh, I had this range I needed to deal with, I gotta get that shadow detail up, I can use the Stand development as a principle for that. In modern day stuff we use a. There's an element called Compensating development, which is very similar to Stand developments. It's an extremely dilute developer that also works under the same principle, but you don't read a lot about that in history as they were dealing with these different film elements and film components. Okay, we're down to one minute. Which is important for me because usually the clock completely faces me and I can just do this, the whole time. The other piece about that, like I said, is don't worry if you miss a little cycle there, it's more important that you. Like if you get to 20, give it an agitation and then just pick it back up. You're better off to hit the agitation at the 20 second mark instead of the 30 second mark if you've missed it, then to not get the agitation in there. That little bit of movement there and the reason the agitation is important is the developer is exhausting even though it's not super dilute or anything, the movement of the fresh developer just let's everything process and develop on it's own. Okay, so I'm at my last little bit here at the bottom. Once I hit this down and turn, I'm gonna pull the cap off. The small cap. (chuckles) Not the big one, we're not light tight yet. We're not light. It can't be exposed to light yet. I'm gonna pull the cap off because we're gonna hit zero, and then normally, if I'm developing here, I would just dump it done the drain. In this case this big jug will become my drain. Developer goes out. Oh I can multitask and we're ready to go into the stop bath. So developers gonna come out. Doug's gonna make that developer go away. Stop bath in this case is just water. I'm gonna pour the water in. This needs to be in there 30 seconds to a minute. Now there's two types of stop bath you can use. One is a chemical-based stop bath agent, or you can use water which is a dilution. Is that just water now.
Cool you can have that too. If it's chemical it's gonna instantly rust the development. It changes the acidic alkaline nature of it, stops the development immediately. Certain films, particularly some of the ADOX films, do not respond well to an acid-based stop bath, it'll actually eat pinholes into the film. I have found that the dilution method actually gets me enough of the rest of the development that is there, it's one less chemical in the dark room. I really like the stop bath. It's job is basically to stop the development. After 30 seconds to a minute, the stop bath will go out. If you're using an actual true stop bath, it's known as an indicator stop bath, it'll change from yellow to a pink or a purple once it's expired, and that tells you it's time for new stuff. For fixer, I'm gonna go on ahead and set my clock here for about five minutes. Fixing is four to five minutes. Oh did we get off the stop, oh it's going. I'm gonna pour the fixer in. Now the fix has a very important job. It's job is to basically turn this into a photograph. At this point it's still a latent image so if we were in a spot and can get to a safe light that had the green wavelength, we could take a look at the film. Yeah I got enough in there. We could take a look at the film and see what it actually look like, what it would continue to build up exposure. The fixers job is to take and wash away any of the latent silver that wasn't attached by the developer. The developers create a metallic silver. This is now removing the rest of the latent image and it's making it stable. Now what's interesting about fix. Oh yeah we should turn on the clock. (chuckles) That was about 30 seconds. You're gonna agitate for about the first minute. Just like we did with the developer and then every 30 seconds, not as critical. Just give it some agitation to get some of that fixer moved around. Interesting thing about fixing the history of it. Fix, fixer, fixing process is accredited by Sir John Herschel, who actually also is accredited with the coining the word photography in 1939. We just called it picture stuff before then. In 1839, so he used the word photography, but Talbot and Daguerre had created images and they were latent images, so they would disappear over time as they were working on that. The story goes Talbot brought in an image to Herschel and Herschel got the image and disappeared and came back, and he said okay it's not gonna happen anymore the image will stay permanently stable. He's like what did you do, he's like I fixed it. That's where they got the word fixer. What he actually exposed it to is something called sodium thiosulfate. Which is Hypo is what the offset of that is. The sodium thiosulfate was able to make the image stable by removing those elements. We used Hypo for years and years and years. With the onset of some of the more modern films, they created something called the Rapid fix. Rapid fix is ammonium thiosulfate based. It's a different chemical property, it doesn't actually have Hypo in it. When we talk about a next stage it's gonna be Hypo Clearing. Technically we're not gonna be doing Hypo Clearing because we're using Rapid fix here which is the ammonium thiosulfate base. They both basically do the same thing. There are still some processes that require sodium thiosulfate to work so you can still purchase it, usually you have to mix it up by hand. You don't go buy jugs of it like you can the Rapid Fix. As you're working with the fix, the other thing that happens is you'll get Fix and some will have what you call a hardener in it, and some won't. Most modern films and papers already have a hardener in them, so they will actually. It's designed to help them not scratch or be as damaged during the process of film development. Like I said some of the ADOX films have a really sensitive emotion, and some of there's prefer to have a hardener, it's not required. I don't use a hardener on any of my stuff and any of my films, I just don't feel I need it. Any of my papers that I use because I tone the papers, you can't introduce a hardener into the printing process, or you can't tone the print. Which we'll talk about what toning is later today. You get through the process of that. You get the fix done. The image at that point is gonna be stable. What's gonna happen next, is at that point, we can look at it under the light. I'm gonna go ahead and in 40 seconds, I'm gonna dump this out, and then we're gonna take a quick peek at the film. What we're gonna look for is has the film successfully cleared. When the fix has done it's job, we call it clearing the film. If it hasn't there's gonna be a light milky haze to the film. It's just gonna be fine here because it's a brand new fix, but it just kind of got this milkiness to it. If it has that, you just put it right back in there and you fix for another minute, minute and a half, and it'll eventually clear. It starts to happen when your fix starts to get old and expired. There's a fix test you can do, you drop some stuff in there it'll particulate out and tell you the fix is there. On a gallon it's 50, 60 rolls of film usually. You can just keep a tick mark of how many rolls you develop for that. Have you ever had a non-clear roll?
Just fix it bonder.
Fix up a new batch of fix.
Yeah, so it's not a big deal also. I'm just gonna dump the fix out back into the fixer container. Drain, drain, drain, drain, dip. Since I wanna pop the top off, I usually make sure I roll and try to get all the goo outta there. Just gonna pull the top off now, pull this out. Looking good Doug! I'm just gonna lightly pull the edge of the film out, and we can see a picture. The film base is the pink base. Which I don't know if I can get it some place. Is pretty clear, so I don't know if you can see it on the film of what's behind it, but that's basically all we're looking for is where does that actually clear up. Now that that's clear, I can go ahead and put that back into the tank. Now what I need to do is I need to rinse that fix off. Normally at this point if I've got running water, I'm gonna go on ahead and running water for about a minute. In this case what I'm gonna do is. I'm gonna do this, and Doug's gonna give me some more water, and I'm gonna do some agitation. Can I have a second. Give me just one of the dumb pitchers too, just empty pitchers, yeah. I'm just gonna do a little bit of agitation to try to get that fix off. Because it's light-tight I'm not super concerned about any of the lid being back on for the fancy pour or anything, it's light-tight now so I'm good. I just want the lid on to not spill. This agitation just helping pull some of that fix off. The fix is the thing that can't ever go down the drain. The reason for that is it has pulled silver off of the film. Silver is a heavy metal. We do not wanna put heavy metal into the waste water system, the septic systems, anything like that. You have to take your fix to a Hazmat Center, or a Reclamation Center, or you can take steel wool and drop it in the bottom of fix, and the steel wool will plate the silver out, and at that point you have a chemical you can chemically unearth and actually deal with simply for that. If you do that you can make thousands of dollars potentially by reclamating the silver if you process enough film. If you develop say 10 rolls a year, yeah, it's not really worth it. The photo center where I teach, the reclamator there is moving a huge volume of fixtures, there's thousands of dollars potentially a plate of silver that's coming off of the film. Okay the next thing I've got is, this is Perma Wash, it's Hypoclear, Perma Wash is a brand name. I always call it Perma Wash. This wash, and this is one of the interesting things, if you get on a big internet in the land of opinions, this is one of the ones in the film world where you will find many of an opinion about whether or not you need to use it if you use a Rapid Fix. I just wanna cover that out for everybody at home who's like Rapid Fix, it says you don't need that. The purpose of this originally was to remove the last of the fixing Hypo, and it shortens the wash cycle. If you don't have this and you're using a Hypo developer, or fixer, you're wash time is another 30 minute range, 20 to 30 minute range. With it, it's about a five minute wash. It's job is to neutralize the acid, and it's a minute or two intermittent agitation, I don't set a clock. I just kind of hmm for a little bit. So, it's job is to reduce acid. If you're using an alkaline fix. There's a company called The Formulary and they have an alkaline fix you would never use this, but it's job is to remove the last of the acid. I still like to use it cause I believe it shortens the wash time, and it will remove any acid that has existed in the water, or is potentially left over. I still use it for my film. I think it's an important part. You still Perm Wash?
I've always done it, but people read and it's not necessary or anything like that. Okay so once the Perma Wash is done, we'll let it go for about another 30 seconds, it's then gotta go to a final wash. The final wash is normally about five to six minutes of lightly running water. All you're trying to do is get the last of the residual chemistry off of the film, so that it becomes archival. The chemistry if it's left onto the film, will actually cause the film to break down over time. So that's what we're trying to avoid. We want these film negatives to last for decades and centuries if possible. We wanna make sure that all of that chemistry that would cause it all to break down, disappear. So that's what that final wash cycle is. It would normally go through that. There is a modified version of washing, so Doug's going to jump in to washing the film. So I'll give that to you and you can do whatever your washing you're gonna do over there. What would then happen is the film would get washed, and then it would come back out, and we'd use a wetting agent on it. Oh I gotta jump ahead of the wetting agent. We use a wetting agent. Now the wetting agent's kind of a cool little piece of technology. Go to the next slide, there we go. What it does is it feels kind of like a soap. It's this really kind of slick solution. What it does is it helps water spots from forming onto the film when it goes to dry. If you don't use the wetting agent, you'll get these water spots, and then you'll have to re-wash the negative to get them off. The wetting agents you're gonna use. The thing about the wetting agent is, the wedding agent is, (chuckles) you don't wanna use too much. It soaps like if you put laundry soap in the dishwasher. It foams and bubbles, so literally in a size containment you got there, one drop of Photo-Flo, agitate for 30 seconds to a minute. Then you're gonna pull the film out, and you'll see people do squeegees and things like that. A few times I take my hand and I'm just gonna basically gonna use my fingers as a squeegee to squeegee it off. At that point the film's ready to go. Doug's washing cycle is actually a variation of something called an Ilford Washing method. It was developed in England when they were on a water shortage during the war. It's just to help hopefully preserve the film because I have some cool photographs on there I would hopefully like to save. He's doing a modified version of the wash. Photo-Flo and then you're gonna hang the film to dry. You're gonna have a little clip at the top, and then you're gonna need a clip at the bottom of the film because if you remember, the film came into you like this. We then put it on a round reel. The film when it's wet will hang like this because of the weight. When it dries, if you don't clip it it'll dry like that. Then you can't get it apart. The emotion will have literally folded onto itself as you start to unroll, you'll hear these weird ripping crinkling noises, and you'll think, even Photoshop can't fix that. A little clip at the bottom, a clip at the top, and you're gonna allow it to dry.