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Amazing Super 8 Reversal One-stop Difference


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#1 santo

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Posted 14 November 2005 - 02:30 PM

Maybe this is more for people new to this thing, but I was so amazed by the difference in this simple experiment I thought I'd put it up for them.

Did a very simple, but very graphic test recently with super 8 reversal Plus-X. When I first got back into super 8 a couple of years ago, I followed the conventional wisdom I had read before from reading slide books and articles on shooting Kodachrome slides of "slight over-exposure or reversal reduces grain, increases sharpness" -- which is the opposite of what you do with negative. I had shot a lot of negative 35mm still, and occasionally over-exposed a little, but noticed very little difference until I got over a stop and then it just came back a little washed out. So I tried the underexpose deal with reversal super 8 and found that it was actually a little grainier, not less so at all. Plus-X, which was pretty much comparible to Kodachrome 40 when exposed properly in the grain department (and about twice as sharp, probably), changed dramatically. So I stopped doing that.

Just for the hell of it, I had a semi-fisheye cut-away shot of a doorway in white for a project I'm working on and decided to do a simple experiment of correctly exposing it, underexposing it one stop, then overexposing it one stop. I was shooting it anyway and it took only a little extra film. The results were really dramatic and certainly points the way to making certain you're aiming as close as possible to the correct exposure for super 8 reversal where everthing is so exagerated compared to other formats. As long as you do that, it's beautiful stuff.


correctly exposed:
Posted Image

underexposed one stop:
Posted Image

overexposed one stop:
Posted Image
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#2 Chris Keth

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Posted 14 November 2005 - 03:17 PM

That advice about overexposure on reversal is exactly opposite of what you should do. Negative likes a bit of overexposure, a thicker negative is almost always a good idea. Plus, a little more light will tighten up the grain structure and make it appear a bit less grainy.

With reversal, the opposite is true. Slight underexposure, or dead-on correct exposure is best for it. Otherwise, you'll get what you have above.
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#3 santo

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Posted 14 November 2005 - 03:41 PM

That advice about overexposure on reversal is exactly opposite of what you should do. Negative likes a bit of overexposure, a thicker negative is almost always a good idea. Plus, a little more light will tighten up the grain structure and make it appear a bit less grainy.

With reversal, the opposite is true. Slight underexposure, or dead-on correct exposure is best for it. Otherwise, you'll get what you have above.


I don't understand, where do I mention advice to overexpose reversal? Is this a mistake on your part? If not, please explain what you mean.
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#4 Chris Keth

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Posted 14 November 2005 - 03:56 PM

...I followed the conventional wisdom I had read before from reading slide books and articles on shooting Kodachrome slides of "slight over-exposure or reversal reduces grain, increases sharpness"...



I assume the "or" in the quotes was meant to be "of" or "on," right?

Edited by Christopher D. Keth, 14 November 2005 - 03:58 PM.

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#5 santo

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Posted 14 November 2005 - 04:13 PM

I assume the "or" in the quotes was meant to be "of" or "on," right?


yep. so you made a mistake in your post, is that what you're saying? nothing wrong in that, except that the way it's worded puts a spin of incorrectness on mine by implying that i was following advice I was not.

but seeing as you brought it up, your "text book" advice to slightly underexpose reversal as being okay does not apply to super 8. as can be clearly seen in the example. rather, it is better to slightly overexpose super 8 reversal than underexpose it (note we're talking 1/3 stop at most) if you're not dead on, which is the best. as can be clearly seen in the example I posted, overexposing a full stop washes out details like the doorknob, but completely eliminates grain. a 1/3 overexposure reduces grain and doesn't blow out your highlights.

so even though you got it wrong, you were right in spite of yourself.

or were you doubly wrong? that's something to think about.

do two wrongs make a right?
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#6 Steve Wallace

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Posted 14 November 2005 - 04:35 PM

yep. so you made a mistake in your post, is that what you're saying? nothing wrong in that, except that the way it's worded puts a spin of incorrectness on mine by implying that i was following advice I was not.

but seeing as you brought it up, your "text book" advice to slightly underexpose reversal as being okay does not apply to super 8. as can be clearly seen in the example. rather, it is better to slightly overexpose super 8 reversal than underexpose it (note we're talking 1/3 stop at most) if you're not dead on, which is the best. as can be clearly seen in the example I posted, overexposing a full stop washes out details like the doorknob, but completely eliminates grain. a 1/3 overexposure reduces grain and doesn't blow out your highlights.

so even though you got it wrong, you were right in spite of yourself.

or were you doubly wrong? that's something to think about.

do two wrongs make a right?

Did you use a grey card? Or did you expose the door as 18% gray. I bring this up, because if i were in the shooting situation. If I were metering the door I would slightly overexpose, not to tighten up the grain. But because the subject is a white door and I don't want it to look like 18% gray. Let me know Santo.
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#7 Chris Keth

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Posted 14 November 2005 - 04:44 PM

yep. so you made a mistake in your post, is that what you're saying? nothing wrong in that, except that the way it's worded puts a spin of incorrectness on mine by implying that i was following advice I was not.

but seeing as you brought it up, your "text book" advice to slightly underexpose reversal as being okay does not apply to super 8. as can be clearly seen in the example. rather, it is better to slightly overexpose super 8 reversal than underexpose it (note we're talking 1/3 stop at most) if you're not dead on, which is the best. as can be clearly seen in the example I posted, overexposing a full stop washes out details like the doorknob, but completely eliminates grain. a 1/3 overexposure reduces grain and doesn't blow out your highlights.

so even though you got it wrong, you were right in spite of yourself.

or were you doubly wrong? that's something to think about.

do two wrongs make a right?



No, I didn't make a mistake. I was pointing out that the advice that you were told was incorrect.

If you were using a subject that wasn't white, you would see the grain that overexposure of reversal causes. Also, since it's a white subject, underexposure causes broad fields of grey, which accentuate any present grain.
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#8 santo

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Posted 14 November 2005 - 05:32 PM

Did you use a grey card? Or did you expose the door as 18% gray. I bring this up, because if i were in the shooting situation. If I were metering the door I would slightly overexpose, not to tighten up the grain. But because the subject is a white door and I don't want it to look like 18% gray. Let me know Santo.


18% grey card.

If you shoot a white subject matter, or one close to white without the grey card, the light meter, which is designed to read everything as 18% gray will read the white door as 18% grey. So it will make the white door grey and underexpose it. Making it a grey, grainy door instead of a clean white one. And how are you going to decide how many stops to overexpose it? One stop beyond the grey card? 2? I couldn't tell you, myself. I'd have to run tests. But shooting from a grey card for exposure seems to hit it pretty darn good in my experience and as you can see in the example.

An invaluable text for shooting black and white film is Kodak's Advanced Black and White Photography. Old now, and you can probably pick it up for a buck or two at a used book store. Great example of photographing white eggs and dark rasberries if my memory is right.

Light meters are the way they are so that a standard of some sort is created from which people can work, and Kodak's grey card is designed to work with it.
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#9 Chris Keth

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Posted 14 November 2005 - 05:34 PM

You just told him something he knew and still didn't answer his question.
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#10 santo

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Posted 14 November 2005 - 05:43 PM

You just told him something he knew and still didn't answer his question.


Look, I don't know what your name is on the filmshooting.com board, but it's clear you're refusing to read my posts and let them sink in.

My first line confirms my answer to his question: 18% grey card.

Now, you can continue to post responses that display that you don't know what you're talking about all you want, and I may continue to answer them because they are in response to my posts and reflect a misunderstanding either honestly or intentionally to provoke something. But it's a waste of your time for me to continue to correct you and have the opportunity to merely refine and clarify what I'm discussing, if your intent is malicious. I just end up "winning".

If you have something constructive to post, please do.
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#11 Chris Keth

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Posted 14 November 2005 - 05:49 PM

I have no problem with you,actually.

I love that someone shoots tests with super 8, it's a fairly neglected format. I would just prefer that you did your tests with tighter standards, it would make them more helpful.

I apologize if I come off wrong, I don't mean to. Truce? :(
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#12 santo

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Posted 14 November 2005 - 05:50 PM

I apologize if I come off wrong, I don't mean to. Truce? :(


Absolutely! My apologies as well.
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#13 Chris Keth

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Posted 14 November 2005 - 05:54 PM

Absolutely! My apologies as well.



Huzzah! :D

Should you do another exposure test like the one above, perhaps you might include a kodak greycard in the scene, the one with 18% grey, high reflectance white and light-sucking velvet all on one card? That sort of standard will help us to see the effects of the test on three different standard values that are constant in every exposure. B)
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#14 andres victorero

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Posted 14 November 2005 - 06:15 PM

I love the S8 test :D

for my taste a bit overexposed looks good, but it depends the film look that you are looking for.

congrats santo ;)
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#15 Steve Wallace

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Posted 14 November 2005 - 06:35 PM

18% grey card.

If you shoot a white subject matter, or one close to white without the grey card, the light meter, which is designed to read everything as 18% gray will read the white door as 18% grey. So it will make the white door grey and underexpose it. Making it a grey, grainy door instead of a clean white one. And how are you going to decide how many stops to overexpose it? One stop beyond the grey card? 2? I couldn't tell you, myself. I'd have to run tests. But shooting from a grey card for exposure seems to hit it pretty darn good in my experience and as you can see in the example.

An invaluable text for shooting black and white film is Kodak's Advanced Black and White Photography. Old now, and you can probably pick it up for a buck or two at a used book store. Great example of photographing white eggs and dark rasberries if my memory is right.

Light meters are the way they are so that a standard of some sort is created from which people can work, and Kodak's grey card is designed to work with it.


The only reason I ask is because the door in the correctly exposed frame looks under exposed to me, and the +1 stop overexposed frame looks only slightly overexposed to me. In fact from the results of this test, I am supprised you used a gray card in this shots at all.

From looking at your samples, I would have guesed that you did an reflective metering off the door. If I had to guess, I would say one can overexpose 2/3rds of a stop in a situation like that to get a nice bright looking door. I'm pretty conservative when it comes to shifting exposure on reversal film.
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#16 santo

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Posted 14 November 2005 - 07:48 PM

I'm more interested in natural than bright-looking, but to each their own. It looks very similiar to the aging white (I guess it's eggshell) door that was there and the lighting at the time from what I can remember. Okay, maybe not so natural as it's lit by a light from below, with the bottom and centre of the door being correctly exposed and then darkening a little up to the top where we start to see a little film grain.

I do agree that the one stop overexposure appears more acceptable than the grainy one stop under exposure, but that's just because of the absence of grain in the one stop over-exposure. most all door handle and lock detail is gone and it's gone soft as has much of the other detail.

In my opinion, if you're looking to make a typical "white" door look really white and bright looking, I'd grey card it and then in post bump it up a little. I suppose you could overexpose from the grey card reading a little, but you risk instant reduction in detail that way in the original picture unless you keep it really slight. Your choice. This isn't really an issue in very forgiving negative film.
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#17 Steve Wallace

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Posted 14 November 2005 - 08:14 PM

In my opinion, if you're looking to make a typical "white" door look really white and bright looking, I'd grey card it and then in post bump it up a little. I suppose you could overexpose from the grey card reading a little, but you risk instant reduction in detail that way in the original picture unless you keep it really slight. Your choice. This isn't really an issue in very forgiving negative film.

Agreed, I think we are probably talking about the difference of 1/3rd of a stop now. I think most of what's in the 1 stop range (half over / half under) is very subjective. To each his/her own.
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#18 Alessandro Machi

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Posted 14 November 2005 - 10:16 PM

I'm very skeptical that your one stop underexposure image is actually only one stop underexposed. It looks closer to two to 2.5 stops underexposed.
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#19 Steve Wallace

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Posted 14 November 2005 - 11:36 PM

I'm very skeptical that your one stop underexposure image is actually only one stop underexposed. It looks closer to two to 2.5 stops underexposed.

That was my argument. I thought the "1 stop + exposure' was 1/3rd over exposed.
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#20 santo

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Posted 15 November 2005 - 08:32 AM

I'm very skeptical that your one stop underexposure image is actually only one stop underexposed. It looks closer to two to 2.5 stops underexposed.


Not as skeptical as I am about you having a pin-registered super 8 camera. So we're even.

Here's what 2 stops underexposed looked like:

Posted Image

Crazy, isn't it? But remember we're not talking about negative stock here. This is old school black and white reversal. You're looking at, what, 7 or 8 stops between pure black and white? Maybe it's a little more. We're looking at half of the Plus-X range with these photos. 4 stops. A couple more to go on the overexposure side, and then another on the undexposure side and we're looking at pure white and pure black images. Maybe it will be 9 stops absolute total -- never tested it that far in this instance -- at the very most. That's just the way it is.

With crappy Kodachrome 40, it's less that this! Maybe only 6 stops between white and black. That's what made it so unworkable for serious film projects. With that crap you're off a stop in either direction and you lose all shadow detail and experience blow-outs and it just looks like bad film.

With black and white reversal, you can get a lot of cool over and underexposure looks, in my opinion -- I posted a couple in the first two images in the "10 Bit Super 8 Transfer" thread. The first one, anyways, is an attempt of mine trying to take full advantage of embracing this narrow latitude to try and give a surreal dream-like effect. But what works for black and white reversal, does not work for Kodachrome 40. It just ends up looking like garbage.

With the new negatives, the stop range is insanely huge next to this.
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