pushing film -- general confusion

[iml]

Great thread, I'm learning lots here.

Ian

 

[Ororaro]

I think what kaiyen is saying is if you use a *spot* meter, you meter off the darker parts, then stop down 2 stops to put those parts on the darker half of the exposure. Otherwise they will come out as middle tones and your brighter parts will be over-exposed re the development. I think if you weren't pushing, you'd stop down four or five stops for the same area. Basically, he's trying to suggest a way to expose for the reduced range of pushed development.

I think it would be well to remember that if one doesn't understand a post, it may be a confusion of language and not a sign of ignorance on the part of the poster. These are rather complex topics, and discussing them requires a certain amount of assumptions and things left unsaid, if only for brevity.

Too much assumptions for nothing.

For brevity's sake, when one talks about exposure, we must assume it's about correct exposure. Otherwise it will get people *thinking*, as you are doing right now, it was about spot metering on a dark part. What else? Measuring a Tortilla in a bright day on a table in a shade?

And even if one is overexposing a shot by 2 stops, there's still no need to underexpose for shadow detail as the details are already there.

I'm only responsing because I found this discussion to be somewhat pointless. Especially when someone who claims he is not an expert starts giving classes.

 

[kaiyen]

Otherwise it will get people *thinking*, as you are doing right now, it was about spot metering on a dark part.

So you're saying that he's assuming that I am talking about metering shadow detail when I didn't say that specifically? Here's a quote from an earlier post of mine in this thread:

"(presuming you are metering just your shadows)."

Sounds like he got it right to me. Too much ignoring what was written on your part, IMO.

What else? Measuring a Tortilla in a bright day on a table in a shade?

Yeah, cuz that's exactly where I was going with that. You read my mind.

I'm only responsing because I found this discussion to be somewhat pointless. Especially when someone who claims he is not an expert starts giving classes.

When the fark did I ever start giving classes? Does a long post count as a class? What the fark is your issue?

If it's pointless, then stop responding. It's not pointless to me because you insinuate that my goal was to give a "class" and have therefore rendered the thread pointless.

allan

 

[MelanieC]

Guys, please stop fighting. I've gotten a lot of good information out of this discussion, and I think other folks have too. It seems like there are many variations with what one can do combining the effects of exposure and development, with myriad different chemical combinations (although with the same principles underlying everything) so it is not a surprise that different practitioners conceptualize the process differently and have different preferences about how they like to get things done.

I for one have been inspired to go back and look at The Negative again (I have all three books; I looked through that one a while back but to be frank didn't understand most of it).

I have yet another naive question -- hopefully it will not stir anything up -- how does all this affect metering if one is using an incident meter? Or a reflected light meter? I use a Sekonic L-308S.

 

[kaiyen]

I have yet another naive question -- hopefully it will not stir anything up -- how does all this affect metering if one is using an incident meter? Or a reflected light meter? I use a Sekonic L-308S.

It doesn't really affect it at all. You would still set the meter to your desired EI (say, 800 or 1600), meter and shoot. In low light situations spot metering isn't as useful. Averaging can almost be better (though a matrix style one, in my opinion, is still best for such situations, but is not available for RFs AFAIK).

What I might do is set the meter at that, and see what shutter speed/f-stop combinations you are able to get at that light level. Depending on the subject(s) and what he/she/it/they are doing - moving, standing relatively still, etc - you can see what you're able to get. You might discover that you're right at the cusp of what you want - like 1/60th at 2.8, which is a little slow for this hypothetical situation. So go to 1/125th at 2.8. You've now pushed another stop (to, say, 1600 from 800), but I'd rather do that than do 1/125th (to freeze motion) and 2.0, which is just getting shallower and shallower DOF.

allan

ps - Melanie - I hope you got my PM. I am sorry that a darker side of me appeared in a thread you started with such excellent intentions.

 

[40oz]

basically, shoot as normal, like the film is 1600 or whatever speed you wish to push to. I tend to lean towards over-exposure rather than under-exposure in dark scenes, while daylight shots don't require that accomodation. Yes, I have pushed Tri-X to 1600 in daylight, it looks fine. IMHO, Tri-X and D-76 1:1 is quite flexible. As long as you expose and develop accordingly, results are fine. I suppose if one specifically was looking for some evidence of pushing, one might find it, but overall, you might as well shoot Tri-X at whatever speed you wish. There might be some issues with extreme pushing, a la reciprocity failure, but for the most part, I've not had any problems up to 3200 EI. I have bigger problems focusing and finding a meter that is readable and reliable at light levels where 3200 EI is required.

Bracketing is probably the best advice, along with practice.

 

[planetjoe]

I haven't been able to get to this thread all day - I'm at a business conference, and there's a fidgety wireless network floating around. Not having RFF on-demand is like being hungry all the time...

Anyway, I just wanted to agree with a couple posters and say this thread has turned out to be informative and...well, even "fun". And Kaiyen, no worries on offense, at least for me. It's all good, and in the cause of better images. How can that be wrong?

And, of course, I wanted to thank Melanie for catalyzing it all. In my opinion, you shouldn't be too concerned about the "fighting"; I didn't even get that impression for a second. Perhaps I'm thick-skinned, I don't know.

Okay, gotta get back to work. Can't wait to get out and continue shooting.


Cheers,
--joe.

 

[kaiyen]

And Kaiyen, no worries on offense, at least for me. It's all good, and in the cause of better images. How can that be wrong?

Good point. And I'm glad you're one of the two or three people I didn't offend in this thread. Just to reiterate, I quoted folks in my original giant post because I was responding to comments, not because I was criticizing the people who said them. I find it good to list what people said and then respond to them. I wasn't attacking them.

One thing that is funny is that I said I wasn't an "expert" in that first big post because I didn't want to sound like a know-it-all. But then I get flamed on what I meant as qualification and humility. Ironic. I don't know it all, by any means.

And it is all in the pursuit of an image, though some of what Melanie has asked has been lost in all this (some of which I created). I feel badly about that.

allan

 

[Simon Larbalestier]

It doesn't really affect it at all. .

Incident and reflective readings measure the light values in a different way don't they? An incident reading isn't affected by the different colours in a subject as it measures the light falling on the subject not reflected off it (as in the case of a reflected type of meter) -different colours absorb different amounts of light which affect the meter reading. At least this is my understanding of it.

In low light situations spot metering isn't as useful.

Allan can you please explain to me why you think this ?

 

[Gabriel M.A.]

By the way, gravity does, indeed, exist.

As long you keep it as two masses pulling each other directly, it should be left at that.

 

[Gabriel M.A.]

Incident and reflective readings measure the light values in a different way don't they? An incident reading isn't affected by the different colours in a subject as it measures the light falling on the subject not reflected off it (as in the case of a reflected type of meter) -different colours absorb different amounts of light which affect the meter reading. At least this is my understanding of it.

This is all very basic, 101 Photography stuff. My hat off to you, Simon and Allan, for your will to go through all of this, in spite of the noise. I had this dissertation written to add to the discussion, but that'd just add more to the confusion.

Cheers!

 

[jano]

Nothing helpful to add, other than this topic is so similar to the title of a book I just read.. "Pushing Ice" -- interestingly, a minor squabble between the protagonists turns into the major driver of the plot.

 

[Simon Larbalestier]

I have a strong tendency to sort-of intentionally underexpose (in dim light, my meter might want 1/15 or 1/30 of a second, but I'll expose at 1/30 or 1/60 because I am worried about camera shake) and then develop the film normally for its rating and so far my results seem fine, or at least, they seem OK to me. Would adding a minute or so to development time be an acceptable substitute for pushing? (The way I look at it, it would be sloppy pushing?)

To get back to Melanie's original question there is a wealth of information in this thread and different pathways to achieving a certain goal. I think it's important to bear in mind what it is you want to acheive as this final goal. A lot will depend on how the photographer wishes to present the images either as a digital print or traditional fibre based prints.

For my part in achieving this goal i want (and get 99% of the time) a negative that is rich enough in tonal scale and contains enough information to enable me to produce an image (either as a scanned negative or print through an enlarger) that reflects my initial pre-visualisation of what i saw before i pressed the shutter.

It would seem to me that you are already getting results you like Melanie - there is certainly no harm in modifying your method so long as the results stay close to what you want to achieve.

You have been the catalyst for a most interesting debate/discussion about how we all percieve the exposure of film. This thread is worth making a sticky or something to make it easily accesible for others to read.

 

[kaiyen]

Simon,
I've been keeping my posts short in order to avoid causing more trouble. But now I'm causing confusion so I guess I can't win. Sorry about that.

Incident and reflective readings measure the light values in a different way don't they?

Yes. But unless I am mis-remembering, there isn't a spot meter or even accurate-to-aim weighted pattern on that meter, so she's just aiming it at a general area. It's hard to account for the different methods that incident vs. reflective meter, IMO, in that situation.

But certainly in a situation when there is a scene with a dominant something or other - a big metal thing with sunlight hitting it - you have to account for that wit a reflective, when you wouldn't for incident.

Allan can you please explain to me why you think this ?

This goes back to my "you lose shadow detail when you underexpose" thing. I general use spot metering to meter the shadows, then a couple of other spots to gauge contrast. Since the shadow density will be lower and I'm underexposing, spot metering the shadows doesn't work as well. At least for me. I rely upon patterned meters in such situations and hope for the best.

allan

 

[Simon Larbalestier]

Simon,
I've been keeping my posts short in order to avoid causing more trouble. But now I'm causing confusion so I guess I can't win. Sorry about that. allan

Allan you're not causing trouble i think we are just trying to explain our own methods of metering and it's not easy and it does get confusing, at least for me and it's interesting for me to see yours as you have gone to some length to patiently explain it.

These things make so much more sense if one was able to demonstrate it in person rather than use subjective words to explain it on an internet forum.

 

[JCT]

Definitely a useful thread as these sorts of interdependent issues can be difficult to understand -- you never know when someone else's approach will resonate "better".

My understanding of the incident vs reflected is similar to Allan's last post. If you are using reflected light for your metering (dome to the side, meter directly pointed at your subject) then you have to keep in mind the issues above, especially if the subject fills your frame well (sticking with Melanie's meter-- it doesn't have spot capabilities)-- the meter will report the correct exposure for 18% grey, if your subject is substantially darker or lighter you have to adjust accordingly or the guy with the black shirt will look like he is wearing a grey one.

If you are metering incident light, (dome in place, standing in the same light as your subject and pointing back at the camera) the ability of the subject to reflect light no longer matters and you can use the meter reading as-is. This is probably why incident metering is sometimes presented as being more "accurate" than reflective -- really a relative thing.

Oh and Melanie, as someone who has been relearning film shooting--- I have found it invaluable to take a roll or two along with a small notebook and take careful notes on each shot -- if you have serious patience you could shoot two identical rolls and alter development times. I did this once to help my teenager get a better feeling for things, it's one of the great things about MF, 12 shots are easy to just reel off. And yes, I make my living in research as well -- kind of like fiddling with lab conditions!

Good luck,

JT

 

[Finder]

Shoot for the shadows and develop for the highlights.

Exposure determines what shadow detail is recorded. Development can do little to increase shadow detail. If you don't expose enough, development is not going to save you. Hence, shoot for the shadows.

Development is a rate process. Changing development changes the contrast of the curve and so development controls the density of the highlights.

The exposure index of a film is based on a speed point - 0.3 above base plus fog if I remember correctly. Push processing underexposes the film and the increased development raises the contrast of the curve so it meets the speed point for the EI used.

Push processing is a compromise. You are going to lose shadow detail. You also have to contend with the increased contrast of the negative - if the subject has a low contrast, it can actually help, but still you may have lost shadow detail. Personally, I never push my film. I alway get the best result from a proper exposure.

I think you are worring too much about slow shutter speeds. 1/30 is easy to hold. 1/15 can work quite often. Practice. But which is better, an underexposed sharp image or a well exposed soft image. It is a toin toss, but I have seen lots of great soft image from the likes of Henri Cartier-Bresson and crowd. My avatar was taken in low light with a maximum aperture of f/3.5. I believe the shutter speed was 1/15s. Perhaps an 1/8s. It gets easier to use slow shutter speeds the more you use them.

 

[Finder]

just one more thought on "develop for the highlights" and Zone System. The idea of developing for the highlights was to control the contrast so the negative could be printed on a specific grade paper - usually No. 2. This was before multigrade paper and saved the photographer from stocking lots of paper of different grades. Multigrade has really made this kind of film development control obsolete. Not to say you should not develop carefully, but you don't for the most part have to worry about scene contrast.

 

[JSFYFE]

Melanie,

A lot depends on the 'range' of the scene you are shooting.

1. Your meter always measures an average light reading the falls on 'middle gray' which is Zone 5 on the zone scale.

2. The Zone scale goes from Zone 0 which is pure black with no detail to Zone 10 which is pure white with no detail. This generally equates to all of the 'shades' on black and white in a scene.

3. If the scene you were shooting had the majority of tones from Zone 3 (dark with good detail) to Zone 7 (white with good detail) then you have some room to play with. (You probably wouldn't know the actual range of tones in a scene unless you had a 1 degree spot meter and measured the darkest and lightest parts of the scene).

4. So, if you take exposure at ISO 400 (Tri-X) according to your meter reading, the range of tones recorded from a scene in #3 above would be from Zone 3 to Zone 8, and 'normal' development would give you a negative with Zones 3 through 8.

5. If you set your meter to ISO 800 (push the film 1 stop), then the negative at normal development will show a scene from Zone 2 to Zone 7. Essentially you have just move the scen 'down' one zone. If you set your meter at ISO 1600 the you have recorded the scene as Zone 1 to Zone 6.

5. Increasing or decreasing development time generally does not affect the lower values (Zone 1 - 3) as much as it affects the higher values (Zone 7 - 8).

6. So, if youe scene originally covered Zones 3 - 8 and you pushed the film 2 stops (to ISO 1600), you will have recorded a scene from Zone 1 (black with very little detail) to Zone 6 (the whites won't be as white as in the original scene). Then you increase development time to move the whites up the Zone scale while not dramatically changing the blacks.

7. If your scene is extremely contrasty (with some Zone 0 and Zone 10 values), you would have a much more difficult problem in pushing or pulling film because then you will automatically push some of the values off of the scale (either the blacks or the whites depending on which way you go with the ISO speed).

Cheers.

 

[vicmortelmans]

That's a very comprehensive explaination of the exposure/development dilemma...

Some conclusions that I make out of it:

When in low contrast environment, take the benefit of it and speed up the ISO setting... nothing can go wrong. You can increase development, but for scanning this may not even be a must...

When in high contrast environment, take some precautions and considerations:
- lower the ISO setting so the shadows are not clipped
- lower development time so the highlights are not clipped
- consider a better metering approach: assuming that the film has 4 zones inbetween zone V and minimum shadow detail zone, you can (spot)meter the shadows and subtract 4 stops from the metered exposure settings. This way you'll avoid the meter to be fooled by e.g. large portion of sky in your contrasty frame...

7. If your scene is extremely contrasty (with some Zone 0 and Zone 10 values), you would have a much more difficult problem in pushing or pulling film because then you will automatically push some of the values off of the scale (either the blacks or the whites depending on which way you go with the ISO speed).

Which again makes pushing a lot less attractive, because it's typically in low light situations that you get a lot of contrast to handle (I'm thinking of indoors scenes illuminated by isolated light sources).


Groeten,

Vic