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FREE BLEACH BYPASS - A rookie takes a risk


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I mean if you like what your getting on film then theres nothing wrong with it.

 

That said, there is no reason to open up with lighter skin when taking an incident reading. The incident reading is just measuring the light hitting the subject, so a lighter object will appear lighter on its own.

 

If you were taking a reflective reading of your subject, then interpreting the reading (and in the example you gave, open up).

 

Kevin Zanit

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I mean if you like what your getting on film then theres nothing wrong with it.

 

That said, there is no reason to open up with lighter skin when taking an incident reading. The incident reading is just measuring the light hitting the subject, so a lighter object will appear lighter on its own.

 

If you were taking a reflective reading of your subject, then interpreting the reading (and in the example you gave, open up).

 

Kevin Zanit

 

This is where i get confused. I understand 35mm photography and in turn reflective metering using the zone system but incident metering isn't as clear for me. If i want a brighter exposure should i just incident meter a darker part of the scene or meter my key light and open up. As i understand it an incident reading gives the correct amount exposure for a 50% grey card but Im never really happy with incident readings - I find they result in dingy images. Is this why it is recommended to rate film stock slower? - compensation for incident readings?

 

I hope that made some sense.

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An incident meter measures the amount of light falling on the dome so that the brightness of the subject is "normal" -- an 18% grey card is 18% grey, a caucasion face is lighter than that, etc. If for creative reasons you want the subject to be exposed brighter than normal, you can do that -- for example, if you want the face to look a stop overexposed.

 

But if you meter a face with an incident meter and expose according to that reading, the object should look normal in brightness, so if you are getting a darker than normal print or transfer, then someone is doing something wrong somewhere.

 

A spot meter measures the reflectance / luminence of an object and assumes that it is 18% grey (Zone 5 I think), so for an object that is actually a stop or one Zone brighter like a caucasian face, you would open up a stop from the meter reading.

 

Now maybe for creative reasons, you like overexposed-looking faces like the example above, but that doesn't mean that you are exposing "normally". You just need to be honest to yourself about how you are metering and exposing the subject.

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Ok that makes a hell of a lot more sense for me. Just a couple of quick questions though - It sounds like incident readings should be failsafe but what about settings that arent under normal illumination. For instance If i wanted a silhouette against a normally lit backdrop should i incident meter the backdrop, incident meter the silhouette and close down appropriately or go for a reflective reading and use the zone system?

If i was to incident meter the silhouette and make no adjustments it would expose it normally and the backgroud would blow out - Is that right?

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You wouldn't really need to meter the silhouette object unless you were worried it wasn't dark enough to go silhouette. You'd meter the background and decide how bright you wanted it to look. Maybe you'd want it to look normal or maybe you'd decide that if it were a stop overexposed it would create a better background to get a cut-out silhouette effect against it.

 

Whether you used a spot meter or an incident meter to determine how to expose would be up to you, you can use either. If the background is something like a window, it's easier to use a spot meter.

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Is this why it is recommended to rate film stock slower? - compensation for incident readings?

 

I hope that made some sense.

 

People tend to rate stock higher to get a denser negative. Also it can reduce grain because film is made up of lots of little silver grain things, and some of them are slower than others so if you give a little more light you expose some of the smaller grains too.

 

When people shoot film they think might be a bit out of date and nasty they might open up a full extra stop in order to try and overcome the base fog. The faster grains are more likely to have gone funny than the slower ones. It's sort of like if your cheese is going mouldy and you cut the bad bits off the outside and make cheese on toast with the better cheese on the inside. Of course you run the risk of getting lysteria or something so it's best to use new cheese if you can afford it. Of course you might be vegan in which case I guess you get a nice video camera instead but then it gets really hard to make pizza, although I had great vegan pizza on boxing day, really amazing.

 

Anyway I hope that sort of makes sense I'm snowed under with stuff so my brain is slightly fuzzy and weird right now, and I'm probably not saying it so well.

 

I hope I didn't misunderstand your question.

 

love

 

Freya

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Thanks Freya, that made complete sense.

Ive decided to go for the bleach bypass. Its pretty nerve wracking because i didnt have money of time to do any tests - All i could manage was a hashed attempt at skip bleach with 35mm stills and a home developing kit. The results aren't perfect but im confident the lab, with its refined processes can make a much better job of it.

post-17246-1203196991.jpg

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People tend to rate stock higher to get a denser negative. Also it can reduce grain because film is made up of lots of little silver grain things, and some of them are slower than others so if you give a little more light you expose some of the smaller grains too.

 

Normally you rate a stock lower -- slower, lower ASA value -- to get a denser negative, like rating 500T at 320 ASA let's say. Rating a stock higher -- faster -- means underexposing and getting a thinner negative (unless you compensate by push-processing.)

 

But the reason you underexpose negative stock that will get a bleach bypass process is that leaving the silver in is like overexposing the negative -- you get a big increase in density. So to get the density closer to normal for negative to be bleach-bypassed, you have to underexpose it.

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This thread is great, as I am in pre-production on a 35mm WWII short which will be shooting early next month. I also will be giving the negative a bleach bypass. David, it's safe to say I could rate Kodak's V1 5219 (500T) at a 320, and meter like I would normally to obtain the underexposure needed when dealing with a BB? How does the extended latitude of this stock affect compensating for a BB, or does it?

Edited by Andrew Brinkhaus
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Normally you rate a stock lower -- slower, lower ASA value -- to get a denser negative, like rating 500T at 320 ASA let's say. Rating a stock higher -- faster -- means underexposing and getting a thinner negative (unless you compensate by push-processing.)

 

eeek! Sorry! How did I manage to type that! Especially as I even quoted Prokopi saying slower!

I did of course mean slower, I knew it would come out all wrong when I typed it. Too much going on right now! :)

 

love

 

Freya

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This thread is great, as I am in pre-production on a 35mm WWII short which will be shooting early next month. I also will be giving the negative a bleach bypass. David, it's safe to say I could rate Kodak's V1 5219 (500T) at a 320, and meter like I would normally to obtain the underexposure needed when dealing with a BB? How does the extended latitude of this stock affect compensating for a BB, or does it?

 

Haven't you been reading this thread? To repeat myself...

 

Bleach-bypass processing the negative leaves a LOT of silver in the film, increasing the density as if you overexposed it by a stop and a half. Most people compensate by underexposing one-stop, thus you'd rate 500 ASA at 1000 ASA. If you rate it at 320 ASA (two-thirds overexposure) and then bleach-bypass (around one and a half stops overexposure effectively) you end up with an incredibly dense negative.

 

I did a bleach-bypass neg process on a short film where I underexposed 1/3 of a stop (rated 400T stock at 500 ASA) and it wasn't enough.

 

Hence why many people use a slower-speed stock, since that also helps reduce grain. You can rate a 200T stock at 400 ASA and then use a bleach-bypass process.

 

The other option, if you don't want to underexpose because it increases graininess, and for some reason you don't want to use a slower stock, is to pull-process to reduce density. So rate 500 ASA stock at 500 ASA, bleach-bypass it -- but also ask for a one-stop pull process.

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Looking at Kevin Zanit's Bleach bypass tests it didnt seem like there was an excessive amount of additional exposure created when not compensating for additional density. With the latitude of slow film couldnt anything but gross overexposure be saved during grading? Does the latitude of stock greatly decrease when bleach bypassing?

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Looking at Kevin Zanit's Bleach bypass tests it didnt seem like there was an excessive amount of additional exposure created when not compensating for additional density. With the latitude of slow film couldnt anything but gross overexposure be saved during grading? Does the latitude of stock greatly decrease when bleach bypassing?

 

Well for one thing, you clearly like overexposed skintones judging from your examples, so what you call normal is what I call overexposed...

 

But I'm just telling you my experience, I rated 400 ASA film at 500 ASA, did a bleach-bypass, and it printed in the mid 40's, which is quite overexposed. We had to retrim the printer because a few colors hit 50, the top of the scale. Now maybe for a video transfer, that much density isn't a problem, but on some telecines, you are going to see some noise in your whites.

 

Now if you're looking for a "hot" effect in the highlights, then maybe you don't need to compensate.

 

This is the reason why you really should test this process before using it.

 

Here are some frames from the short film where I did a skip-bleach to F-400T:

 

stuck1.JPEG

 

stuck2.JPEG

 

stuck3.JPEG

 

stuck5.JPEG

 

stuck7.JPEG

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Does the latitude of stock greatly decrease when bleach bypassing?

In effect, yes. Bleach bypass increases the contrast of the negative, particularly towards the highlight end of the range. While the neg can still record the same range of original subject (scene) tones, it records them with a greater range of densities (i.e higher gamma). The only way you can capture this range of densities on print or on telecine is either to crush or burn, or (in the case of telecine) to reduce contrast (and still crush or burn a little bit).

 

David Mullen wrote:-

I did a bleach-bypass neg process on a short film

A question to David: Did you test the bleach bypass?

 

This site is a great resource for people seeking advice on how to shoot their film. In a lot of cases it's useful to understand (for example) what happens if you leave yor 85 filter off - can it be corrected?

 

But something as extreme as bleach bypass is different. The bleach bypass prcess effectively gives you a colour negative PLUS a black and white negative bound up together in the one piece of film. In fact if you shot a colour neg and a black and white neg, processed both (admittedly the b/w neg at a much lower gamma than usual) and bound them up together, you'd have the same result. I'm not suggesting you do that - it just might help visualise what you are doing to your negative.

 

You can learn that it increases contrast, that it reduces saturation, that you need to reduce exposure, that it increases graininess, that the effect is more extreme on high speed stocks, that it will cost you extra at the lab and probably take longer, and that if you don't like it you can have the neg reprocessed (at the full rate for negative processing, and who's going to pay for that) and you will end up with a neg that is as underexposed as you (presumably) shot it.

 

But you can't learn what it will look like on YOUR material.

 

If you are going into this without testing, let alone without having shot film for normal process, then good luck. I guess you know it's quite a risk. Be sure to let us know how it turns out.

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Well for one thing, you clearly like overexposed skintones judging from your examples, so what you call normal is what I call overexposed...

 

But I'm just telling you my experience, I rated 400 ASA film at 500 ASA, did a bleach-bypass, and it printed in the mid 40's, which is quite overexposed. We had to retrim the printer because a few colors hit 50, the top of the scale. Now maybe for a video transfer, that much density isn't a problem, but on some telecines, you are going to see some noise in your whites.

 

Now if you're looking for a "hot" effect in the highlights, then maybe you don't need to compensate.

 

This is the reason why you really should test this process before using it.

 

Here are some frames from the short film where I did a skip-bleach to F-400T:

 

stuck1.JPEG

 

stuck2.JPEG

 

stuck3.JPEG

 

stuck5.JPEG

 

stuck7.JPEG

 

Hi David,

I am shooting a s-16 short with full BB on neg at a similar location as your photo references. I would like to know how did you balance the exposure with sky and your actor in foreground. did you use additional light for the actor's face or bounce off the sun? and the sky seem exposed normal especially with a full BB, did you ND the lens? I assume you used Fuji 400 ASA, is it right? thanks for your help

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