Using different "Variable Contrast" filters for the same single contact print.

[Pere Casals]

As I was contact printing a difficult 8x10 negative I found than I could use more than one Variable contrast filter with the same print.

The scene had 8 stops dynamic range and N-4 development was made. Min negative density was 0.1D and Max was 2.6.


First I made a general exposition of 6s with filter No. 2 (Ilford), and then I was burning dense negative areas (adding 40s) with a No. 4. replacing the No. 2.

I'd like to know if more people experimented with that and how you apply that resorce. How microcontrast can be enhanced...

[Tin Can]

I do it, it's almost intuitive.

Split grade.

I don't analyze as you do. No possible way to keep up.

:)

[Pere Casals]

I do it, it's almost intuitive.

Split grade.

I don't analyze as you do. No possible way to keep up.

:)


Thanks, I didn't know the name... by searching "split grade" I found a lot of reading...

[interneg]

As I was contact printing a difficult 8x10 negative I found than I could use more than one Variable contrast filter with the same print.

The scene had 8 stops dynamic range and N-4 development was made. Min negative density was 0.1D and Max was 2.6.


First I made a general exposition of 6s with filter No. 2 (Ilford), and then I was burning dense negative areas (adding 40s) with a No. 4. replacing the No. 2.

I'd like to know if more people experimented with that and how you apply that resorce. How microcontrast can be enhanced...

I use multiple filters all the time - a baseline filter, then bits of 0/00 and 5 for dodge & burn when needed - lets you exploit the strengths of Multigrade papers. Split-grade is a bit of a misnomer - unless you're dodging and burning on the different grades, all you're doing is ending up back at a specific grade.

More fundamentally: 8 stops & N-4? Really? Under normal circumstances you'd probably be looking for a CI in the mid-low 0.5 range - N-1 range in other words, not that it'd be unprintable at N on a softer grade.

Microcontrast enhancement is something more easily effected by the use of register masks.

[Pere Casals]

I use multiple filters all the time - a baseline filter, then bits of 0/00 and 5 for dodge & burn when needed - lets you exploit the strengths of Multigrade papers. Split-grade is a bit of a misnomer - unless you're dodging and burning on the different grades, all you're doing is ending up back at a specific grade.

More fundamentally: 8 stops & N-4? Really? Under normal circumstances you'd probably be looking for a CI in the mid-low 0.5 range - N-1 range in other words, not that it'd be unprintable at N on a softer grade.

Microcontrast enhancement is something more easily effected by the use of register masks.



It is this HP5+ shot https://www.flickr.com/photos/125592977@N05/24852468435/in/dateposted-public/

At the used exposure the dark walls was at -2 stops (ZIII) and the clock at the tower was at +6 (ZXI). Development was 20ºC, Xtol 1:1, 8:30min, reduced agitation in tray (a shake min 3:30 and very gentle shake at min 6:00)

But exposition was compensated by reprocity failure for the shadow, so lights where in fact at ZXII or XIII in very illuminated areas. The scene had 8 stops but with reprocity it became some 10.


With 00 I had dull print and still burnt illuminated areas... at the end I used 2.5 filter general and 0/5 filter for different areas


From what you say... perhaps a way to increase microcontrast it is burning a low contrast area with 5 Filter ??

After a 12 contact prints test I still found that burning on the tower's clock the white there became dirt while clock hands were not black enough, I plan to burn it (green encircled area) with 5 filter and to use 0 filter for yellow marked areas as shown here:

154370


I'm thinking that with a not very contrasted flat negative with "split contrast" it's like an "specific grade", but with a contrasty negative perhaps.... does it modify the general gamma value?


From what happened with the clock hands I guess I can enhance local microcontrast by dodging a bit in an area while making the general exposure, and later burning same area with 5 Filter...

[Tin Can]

Pins and masks are next

[Pere Casals]

Pins and masks are next

Also a 40x magnifier to delight the contact print fineness, I found that an 8x comes short :)

[interneg]

I think you're dealing with a compounded set of errors - dense, flat highlights sound a lot like overexposure & overdevelopment. It would be useful to see a picture of the actual negative to see what we're dealing with.

You might find it useful to read Howard Bond's tests on HP5+ which suggest that it & a number of other modern films have much less reciprocity error than the generic published curves would suggest - http://www.willwilson.com/articles/0403Bond_Reciprocity2.pdf You may have significantly overexposed your negative. I'd generally say that out to about 10s, his results chime with my own experiences.

Your usage of XTOL is strange too - extended agitation intervals (not stand, not semi-stand) can be useful but not realistically at anything less than 1+2 or 1+3. Even then I'd question their usefulness in many circumstances. I would not be surprised if your negative has been developed to too high a contrast index. Furthermore, I suspect that a development time in the lower end of the 6-7 minute range with standard intermittent agitation at 20c may not be too wide of the mark. If you need any more contrast reduction than that, unsharp masking makes a lot more sense. What was your Effective Film Speed?

I should be noted however that this approach will generally result in a print with opened shadows that may not reflect the reality of the scene as you saw it. Keying to the highlights & altering your development approach may be better, depending on what you want.

It's also important to note that the linear behaviour of a scanner allows it to record data that can end up being compressed into the toe of the paper at a given contrast grade.

Finally, 'microcontrast' is a bit of a misnomer & has much more to do with lens design & MTF. The ultimate way of enhancing highlight separation in tricky situations is a bump mask - rarely needed except when dealing with awkward exposures of snow & things like that - it also needs pin registration.

[Pere Casals]

I think you're dealing with a compounded set of errors - dense, flat highlights sound a lot like overexposure & overdevelopment. It would be useful to see a picture of the actual negative to see what we're dealing with.


In this pictures it can be seen the densities of areas and the metering at stairs and at the clock, now this accounts for a correction folllowing the values given in your link

http://www.willwilson.com/articles/0403Bond_Reciprocity2.pdf

154388

Max density is lower that the 2.6D I said in the first post, this time I measured it with a good densitometer.

This is the scanned negative:

https://www.flickr.com/photos/125592977@N05/24852468435/in/dateposted-public/

https://www.flickr.com/photos/125592977@N05/24534566679/in/dateposted-public/

https://www.flickr.com/photos/125592977@N05/24875860836/in/dateposted-public/








Your usage of XTOL is strange too - extended agitation intervals (not stand, not semi-stand) can be useful but not realistically at anything less than 1+2 or 1+3. Even then I'd question their usefulness in many circumstances. I would not be surprised if your negative has been developed to too high a contrast index. Furthermore, I suspect that a development time in the lower end of the 6-7 minute range with standard intermittent agitation at 20c may not be too wide of the mark. If you need any more contrast reduction than that, unsharp masking makes a lot more sense. What was your Effective Film Speed?


HP5+was shot at ISO 25, if reduced agitation did not pull an full stop then it was ISO 50 to ISO 80, I guess. XTol 1:1 12min has effective speed ISO 400, at 10:25min it's ISO 100-200 and at 8:30 it should be ISO 50-100

I guess I have to make a film calibration with a Stouffer gauge with that agitation to find what true effective ISO speed is there, I plan to do it...





Finally, 'microcontrast' is a bit of a misnomer & has much more to do with lens design & MTF.

I was attempting to increase local contrast at the clock area by burning with filter No.5 in place, to get clock hands darkened... also roman numbers for the hours.


So given the scene described in the picture, being exposure f/16 / 25s... what exposure / development would have you adviced ?

TMX or TXP would had another behaviour?

Any suggestion for the print?


Thanks in advance!

[ic-racer]

I have reduced it down to a base exposure with mixed yellow and magenta (the mixing allows me to hone in on contrast and exposure easier, as one can imagine).

Then, I frequently burn with white light. The white light contains red which is non-contributory. The white light contains blue which has little effect on highlights and the white light contains green which burns the highlights.

Sure, you can filter out all the other stuff with a yellow filter, but in my workflow, there is no need.

[Pere Casals]

I have reduced it down to a base exposure with mixed yellow and magenta (the mixing allows me to hone in on contrast and exposure easier, as one can imagine).

Then, I frequently burn with white light. The white light contains red which is non-contributory. The white light contains blue which has little effect on highlights and the white light contains green which burns the highlights.

Sure, you can filter out all the other stuff with a yellow filter, but in my workflow, there is no need.


Ok, I understand... also with white light on can see better what he is burning...

[interneg]

Are those numbers off the negative? If they are, that's a very long scale negative & one I'd probably only try silver gelatin printing after unsharp masking. Too many awkward dodges & burns otherwise. The 1.8-2.0 range you're in is in the 00 contrast range - where many papers don't perform terribly well - it might make a good salt/ carbon/ albumen print though. 1.1 is G2 range, just to give you an idea.

If you have access to a good quality densitometer, and too much time to waste on such things, do the full range of BTZS tests - they'll tell you a lot more about your process & relationships between film & paper curves. Get a lightmeter that reads in EV - it'll make your life easier too. No need to change films - HP5 is pretty tolerant & tough.

Finally, the problem you were having with 'muddy' tonal values while burning in sounds a lot like overexposure at too high a contrast grade - I see it regularly amongst inexperienced printers.

[Pere Casals]

Are those numbers off the negative? If they are, that's a very long scale negative & one I'd probably only try silver gelatin printing after unsharp masking. Too many awkward dodges & burns otherwise. The 1.8-2.0 range you're in is in the 00 contrast range - where many papers don't perform terribly well - it might make a good salt/ carbon/ albumen print though. 1.1 is G2 range, just to give you an idea.


Yes, a very long scale, even with N-4 (or perhaps is N-3) development I made. With 00 also burning was required, and general it resulted dull.

From what you point I read that http://www.largeformatphotography.info/unsharp/ I'm to learn it.

But only a single dodging is required (marked in blue in the picture) , then the series of burnings...



If you have access to a good quality densitometer, and too much time to waste on such things, do the full range of BTZS tests - they'll tell you a lot more about your process & relationships between film & paper curves. Get a lightmeter that reads in EV - it'll make your life easier too. No need to change films - HP5 is pretty tolerant & tough.

Finally, the problem you were having with 'muddy' tonal values while burning in sounds a lot like overexposure at too high a contrast grade - I see it regularly amongst inexperienced printers.


I'll follow your advice, I'll make BTZS graphs for film and paper.


Yes, the muddy face of th clock it was because burning overexposure with grade 2.5 Filter, the were not black enough while the clock face was going grey, so perhaps it has to take less burning but with the 5 filter in place...

Thanks for your advice, in fact those are my second series of prints!

Perhaps it's a difficult negative to learn from, anyway this motivates me :)