Strange, why they are underlining that. If you push you compress the tones every time
Sheet film - FOMA vs Ilford
-
A
- Thread starter ParkerSmithPhoto
- Start date
Recent Classifieds
-
For Sale FS: Linhof Recessed lens board
- Started by dirkfletcher
-
For Sale Leica M4-2
- Started by chriscrawfordphoto
-
For Sale FS: Toyo Sliding Back for 4x5 Graflok
- Started by B.S.Kumar
Forum statistics
Strange, why they are underlining that. If you push you compress the tones every time
Yes... IMO Fotoimpex comercial description is for the pushing condition, as Microphen is an Speed Increasing developer it is often used for pushing to get an slighter better detail in the extreme shadows.
If you see the graph at 5 min we have som 2,75 Log H units each worth 3+1/3 stops, totaling 9 linear stops, if we discard the last stop in the extreme shadows then we have 8 good quality linear stops. If you take a close look at the curves you will find that curves at 7min and 11 min start shouldering after reaching density 2.0D, while the 5min has been shown until 2.0D (perhaps to show an straight line) not saying what is to happen at higher exposures, probably going beyond 2.0D the 5min curve is to show a shoulder.
Shouldering in the highlights depends on the emulsion design, a higher presence of small low sensitivity crystals, its sensitization and arrangement in layers is what shapes the curve in the extreme highlights after reaching a certain density level, if we pull development then the shouldering happens at higher expoures. In that way, from adjusting development , we can adjust at what overexposure we'll have the shouldering, at the same time we pull we also get a lower Contrast Index that is to be compensated with the printing contrast grade or Photoshop curve edition.
...we have some evident factors:
> Emulsion nature, TMax is designed to be linear at very extreme densities...
> Development time... shortening development we have the shoulder at higher overexposures, if pushing we have the shoulder earlier.
> Developer kind, a more energic developer (more alkaline for example) helps infectious development, non exposed crystals starts development when in contact with other that are being developed, provocating some effect in the sepeed/curve, beyond grain size.
> Compensation, for example a reduced agitation selectively slows development in the highlights... helping the shoulder to appear.
Shoulder is not good or bad, it can be a very interesting resource for darkroom printing or a sound pitfall that will end blocking highlights !
They're essentially trying to explain that unlike many developers, Microphen's development rate doesn't really slow down as you push beyond ISO contrast, which makes it less controllable with films prone to building contrast (Fomapan) especially at raised temperatures. I've attached a document from an old HP5+ data sheet which shows the relative development rates of various Ilford developers - '0' is the equivalent of 'N'/ G-bar 0.62 development placing 7 stops on a nominal G2 paper, whereas if you developed to the '-1' marker, you'd need G1 paper to handle the same 7 stops of subject range - and so forth. You can see that Microphen (even on HP5+ which has quite relaxed development rates) has a steeper overall development rate gradient, which will reduce your margin of error at 20oC, let alone anything higher. Their description of the way the shadows are effectively crushed and the mids/ high shoved up onto the shoulder can (if exposed correctly) make a neg that delivers something pretty remarkable on a high grade of paper - Art 300 at G4 and upwards, then bleach/ sulfide/ gold toned does pretty well with this sort of neg - brings the grain out strongly.
For what it's worth, the published characteristic curves for Fomapan 100/200/400 seem totally identical (even generic), with the development timings changed on each to suggest what extended development might do, rather than what it specifically does to each particular emulsion. Fiddling with agitation does not generally do much other than adjust the overall rate of development - which will obviously alter the effective highlight density (and straight line gradient) - it doesn't increase or decrease shouldering any more or less than an equivalent adjustment in developing time will (with regular agitation).
Attachments
Last edited:
I suspect the highlights in the grass and the chimney would be completely blown out, but in what way would this improve the image? Even if the highlights weren't pushed too far by the overexposure, wouldn't a shortened development time lead to a thinner negative, and therefore less overall contrast?
What problem would greater exposure and shorter development time address?
FYI, the highlights were measured around EV 15, and the shadows around EV 8, as mentioned in another post.
It would lower the gradient of the curve and reduce the density in the highlights (and reduce shouldering too), letting you compress (say) 8 stops of useful range into the 7 that (on average) grade 2 paper is intended to handle (this is effectively 'N-1'). It'll also lengthen the toe somewhat. In part, that's what the extra exposure is intended to address. If you're keying to shadows, the actual amount of extra exposure is usually very little indeed (1/3 stop or so, maybe). Overdoing the ovexposure/ underdevelopment thing can produce negs that are difficult to print in a different way - because they lack enough shadow/ mid contrast relative to the gradient of the paper, because too much emphasis has been put on holding every last highlight detail on the straight line. With modern multicontrast papers, there are very few reasons to go below N-1.
This is a 8 stops range, 15-8 = 7, but if you have spots in the lower part of EV 8 part and in the higher part of EV 15 the range is 8 stops.
Considering the Foma nature, you have to pull development if you want linearity in the full range. If you want to take advantage of the shoulder to compress highlights (to be printed easier in the darkroom) then standard C.I. (or higher may work), but to have control you need to know the sensitivity shows the shoulder depending on spot metered overexposure.
Of course !!! But you may get the same contrast in the print than if not pullling. Many "Fine Art" Large Format photographers are all day long pulling or pushing, and Zone Systems instructs to constantly pulling or pushing depending on the scene, so there is nothing wrong in crafting a thinner or lower than standard contrast negative, you later use the right paper grade to get the image you want. By pullng you lose some actual speed, may be a 1/3 stop, which is introduced in the exposure decision.
Personally many times I pull 2 or 3 stops for challenging scenes (specially for night shots), contrast is different... but later we have paper from 00 to 5 grades to nail the print like we want it.
Expose for the shadows, develop for the highlights. This is the gold rule.
A greater exposure would deliver better detail in the extreme shadows, (no doubt here), but at the same time your extreme highlights will be more overexposed and this may end in compressing compressing ehighlights too much of even clipping those highlights...
... but if you shorten development you don't allow those extreme highlights to reach too much high densities. By shortening development you don't change much the shadows (beyond that 1/3 stop speed loss) but you change a lot highlights.
Off course, as mentioned, if you pull then Contrast Index will vary, but it is largely irrelevant if C.I. is higher or lower, photopaper grades allow all required flexibility to make the print you want.
Also pulling tends to decrease grain size, as grains have less time to grow.
Suggestion:
It looks you are not satisfied with that result... ok, return there (or take a similar scene) and make a practical test:
> Split a 35mm roll in 3 rolls, (or burn three 24 exp. rolls).
> Spot meter and take notes.
> Bracket (say) -1.5 / 0 / +1.5 / +3 , repeat for each of the 3 rolls you have, so you have 3 rolls each with the same bracketing.
> Develop each roll differently, say 0, -1.5, -3
You have each spot (notes) taken at very different exposures, and for each exposure you have 3 developments.
Probably you would find that +2 overexposure with -1.5 development would deliver nice shadow and highlight detail with the image you posted, but may be contrast will have to be increased in the printing or in the edition. Still, having all those bracketed shots with different developments would be quite informative because when you decide an exposure development then you may have to sacrifice something, in that way you can predict waht you sacrifice or not.
If no developer/bracketing in the test suits your taste then abandon that film/developer/processing combination...
Jay DeFehr (https://www.flickr.com/photos/jay_defehr/) formulated the 510-Pyro developer, in his Flickr gallery you may find examples with Foma 400 and many other films, this is a nice example to tell that photo materials are flexible, more than the material itself what matters is what we do with the materials.
That sounds interesting effect.. I wish there was some examples of this. I tried to google but didn't find any.
Thanks for the explanations (you too 138S).
@138S: No, I'm fine with the result-- my takeaway from the conversation is that if you want to print via enlarger, you probably *do* want to overexpose Foma 400-- if your end result is primarily digital (which mine is right now), exposing at box speed seems to be the way to go.
Personally, even though this was no more than a lens test (I took the same shot with all 4 of my current lenses), I'm reasonably satisfied with how the shot turned out-- I have highlight detail on the chimney (although since in real life it's a red-brick chimney, it's still a bit heavy on exposure-- as you note, I was hitting 7+ stops, which I've found with foma/arista 400 to be about it's breaking point), and other than under the porch (where I'm not particularly interested in shadow detail), I have plenty of detail in the woods.
But much of your response appears to be theorycraft, and that was the point in posting this particular photograph-- there's been a lot of theory in this discussion, but little discussion of specifics: where in this photo do I need more shadow detail? Are the shadows "muddy"? Have I preserved highlight detail? I'm familiar with "expose for the shadows, develop for the highlights", but without context, it's a largely meaningless mantra.
In the case of this photograph, my "final" version adds a bit of sharpening to compensate for the Epson, and a slight tone curve to give a more pleasant image (increasing the shadow area's "darkness" slightly, while keeping the highlights about where they are)-- easy enough in the digital realm, but verging on split grade when printing.
Personally, even though this was no more than a lens test (I took the same shot with all 4 of my current lenses), I'm reasonably satisfied with how the shot turned out-- I have highlight detail on the chimney (although since in real life it's a red-brick chimney, it's still a bit heavy on exposure-- as you note, I was hitting 7+ stops, which I've found with foma/arista 400 to be about it's breaking point), and other than under the porch (where I'm not particularly interested in shadow detail), I have plenty of detail in the woods.
But much of your response appears to be theorycraft, and that was the point in posting this particular photograph-- there's been a lot of theory in this discussion, but little discussion of specifics: where in this photo do I need more shadow detail? Are the shadows "muddy"? Have I preserved highlight detail? I'm familiar with "expose for the shadows, develop for the highlights", but without context, it's a largely meaningless mantra.
In the case of this photograph, my "final" version adds a bit of sharpening to compensate for the Epson, and a slight tone curve to give a more pleasant image (increasing the shadow area's "darkness" slightly, while keeping the highlights about where they are)-- easy enough in the digital realm, but verging on split grade when printing.
@grat I wouldn't want to make sweeping statements without seeing the original neg, but from all you describe about the exposure etc, I think it would probably print just fine on a normal-ish grade. You might find it prints almost exactly as per your inversion, or that the shadows go a little darker (because of the linearity of scanner response vis-a-vis paper shoulder shape) and the highlights need burnt in a bit more. If you didn't have to do specific work in post production to keep the highlights from going muddy, it's likely they'll print pretty well in the dark too - though I can't say immediately if/ how much burning/ flashing/ fogging they might need. 'Split-grade' is essentially a marketing mantra used to sell equipment (though it definitely has uses for landing a time/ grade at speed (there are even lazier ways involving a couple of quick densitometer readings, but let's not get distracted by that...)) - being able to punch in any grade at will is incredibly handy - I don't get worried about landing on a 'perfect' grade, but rather that the shadows have enough exposure for detail, the midtones have a good gradient that isn't too flat (this is really important), and that I can bring in the highlights without them becoming muddy and flat. What that often means is that I generally prefer negs a hair under ISO contrast (with exceptions) - but probably not below a g-bar of 0.5-0.53-ish (the '+1/2' times on the Ilford sheet upthread may not be far off that for you), unless the light is consistently flat - then I might prefer to boost it up into the 0.7's, just to give me a little more range to really punch-in contrast if needed. In simpler terms, I like a neg with good shadow detail, not too steep mids, and not overly dense highlights, but which still have good separation (unless I intentionally want specific effects) - makes it easy to get nice highlight gradation, and I can print down the shadows if I want. You'd also be surprised at how malleable fixed grade papers are, even without much in the way of developer manipulation... It's more a case of getting close enough to have the source material to make a good print, rather than exactly reproducing the scene.
Last edited:
Sorry, I evaluated your image from an uncalibrated/bad monitor, now in a calibrated/good monitor it looks way better...
All depends on how one meters, but in general Foma 400 Box Speed is optimistic compared to ilford/kodak. Foma used an speed boosting developer and a higher gradient for the calibration. If calibrating Foma 400 ISO Speed in Full Speed developers a lower true ISO speed (than the box one) would be found, you may find several calibration posted in this site.
Still, let me reiterate that the way one meters has an impact, at the end we all adjust several factors in the exposure calculation from feedback...
IMO if it is a linear film then overexposing may be the way to go for scanning, not for darkroom printing. An Epson V850 has no problem with very high densities (say 2.8D) that are very difficult to handle in the darkroom, so for hybrid you may take deep shadow detail without having a problem with extreme highlights, if the film records linearly that.
Instead for darkroom printing you need to balance way better the exposure, any print manipulation is always more challenging in the darkroom, so crafting a negative that's easier to print can be a priority.
Well, being a 7 stops range, it looks to me that the chimney could have better texture if pulling development a bit, the detail it has looks a bit from the shoulder... if pulling a bit then (IMO) de detail in the chimney would be more in the linear region.
Suposing you placed EV 8 in the Speed Point then your chimney would be in the red squares of the graph bellow, for the pushed development (curve 3) you are clearly in the shoulder, for the recommended development (2) the chimney is starting to shoulder, but if you pull then the chimney is in the linear region. But if you placed the extreme shadows (you metered at EV8) a bit in the right side of the Speed Point then that shouldering increases. Each H unit in the Hor axis is 3.33 stops.
What I want to show is that develoment influences the linear dynamic range of the film, and that this has an impact specially for those (more classic) films not much designed to be linear in the extreme highlights.
Sorry if I was not clear, I only was pointing that IMO you could have enhanced detail quality in EV 15 metered zones by pulling development, you have detail in the chimney and in the foreground pole, ok... but if you want better detail there then you may pull. In fact this is what ZS recommends, the chimney was perhaps in Z-XIII or Z-IX, if you pull one or two stops then you have that in (say) Z-VII offering better detail: the red square in curve 1. Very linear films (TMax) conserve better the extreme highlight detail, but that detail can be more difficult to print in the darkroom as very high densities are reached.
This opinion comes from theory and from practice, I teach myself by predicting the densities I'm to obtain in metered spots of challenging scenes, later I check if the negative has those densities and what detail quality I get there, I do that since 2016 (https://www.flickr.com/photos/125592977@N05/28693688313/). This is something I would recommend to anyone wanting to have better control: just from time to time try to predict densities and later check if the prediction works, of course there are other very good ways to learn how a film behaves, but I feel that this way helped me a lot to understand the medium, which I felt I needed to re-engage darkroom printing.
Last edited:
While hitting my head on the wall printing countless bad negatives, this has come more and more imporant to me too. I'm quite impulsive person so it is pretty hard to concentrate and remember everything. Sometimes I just cannot give a damn about it and I just want to photograph.
I also would like to have some kind of interactive visualization for development + paper printing. It would be nice to play around and get "hands on" (altough just a simulation) on the matter. A feedback loop which I could use to teach my brain.. Doing it on real film is a bit too slow feedback loop
It was at least exposed for the shadow details as you have detail all the way up underneath the porch awning. There is no such thing as correct or incorrect exposure. There's exposure that gives you details in the parts of the composition that you want details in, and exposure that doesn't. If you're getting details in the parts you want and the film has enough density range to handle the brighter parts of the image without totally shouldering over, then that's all that matters. If you're not, then if you can, make another exposure with more light.
What the highlights look like depends a lot on the developer used. XTOL has a lot of trouble building good highlights on Foma 400. Other developers don't seem to have as much trouble doing that.
Interesting thanks. So then reports suggesting Fomadon Excel is an XTOL clone must be incorrect, as I find Foma 400 gives incredible tonal range in the highlights using Excel in 1+1. I meant to try Xtol at some point, wondering if Excel is only a clone of some past formulation of Xtol, and by using Xtol I could get even better result, but it sounds like I should stick to Excel.
my experience is with replenished xtol, which tends not to behave the same way as full strength or diluted.
Do you have any proof on this or is this pure feeling?
I don't mean to attack, but it would be nice to see examples or tests or this kind of claims. Otherwise we are just running in circles here..
edit: I mean we have some way to test this out, right?
-
- 138S
- Deleted
this is why I do film tests and post them here.
https://www.photrio.com/forum/resou...plenished-xtol-for-8-45-at-24c-in-a-jobo.427/
That is so great. Thanks.
I know your backgrounds but oh how I wish the tests would have been done with some really "general" way like using Rodinal, D-76 or Xtol 1+1 and using normal tank agitation
That is so great. Thanks.
I know your backgrounds but oh how I wish the tests would have been done with some really "general" way like using Rodinal, D-76 or Xtol 1+1 and using normal tank agitation
Well, I documented how I do it. I chose the methods I did so anybody can roughly reproduce it with the most basic of equipment. I totally understand the desire to see this info using other developers, however, that takes time and costs money, and I can’t please everybody.
| Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links. To read our full affiliate disclosure statement please click Here. |
PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:  |