FX-1 acutance

pentaxuser · Thursday at 7:31 PM

koraks said:
You could? I didn't notice it. I did hear him talk about it around 7:30, but frankly, I don't see anything of the sort in the video. I'm also not quite sure how I'm supposed to see any Mackie lines in a YouTube video of a negative. I do see all sorts of compression and digital sharpening artifacts. Whereabouts did you see any Mackie lines?

It was just about visible on the outline of the rock put in shadow but in Part 2 of the video not Part 1 above to which I had wrongly made reference

Here's part 2 the reference is at about 14:27

I was also wrong about him making no comparison He does also in Part 2 at about 14:48

My apologies about both mistakes

pentaxuser

Milpool · Thursday at 7:42 PM

pentaxuser seems to have responded to an old post but anyway…

FX-1 would likely be a reasonable candidate for edge effects (assuming that is how one wants to define acutance but that’s another matter). It’s similar to Beutler but with less metol, which should help.

I’m basing this on a RIT study (link below) on edge effects. Granted it’s from the early 1980s but good enough. It included Beutler as one of the control developers and in the metol-only series some of the relevant test formulas might be PZ-13/14, 22/23, 62/63.

Anyhow for those interested: https://repository.rit.edu/cgi/viewcontent.cgi?article=7664&context=theses

koraks · Friday at 1:59 AM

pentaxuser said:
Here's part 2 the reference is at about 14:27

Oh, OK, thanks. I can't see the supposed Mackie line in the horizon. If I take that area he's pointing at, there is something going on that may be due to development edge effects for sure:

but it's literally everywhere except the horizon he's pointing at (there is an odd hairline artifact above the horizon that seems to be purely digital in nature and has nothing to do with the actual print).
So, not saying it isn't there, just that YouTube is a terrible medium for trying to convey these things.

pentaxuser · Friday at 2:41 PM

What I was hoping for from users of FX1 was their experience of its speed increasing effect or not as the case may be. John Finch who does use a speed test to check what is in fact his own EI said that he got 200 out of FP4+ He hasn't been one to make such claims without testing so it made me curious

koraks I could definitely see some thing in the area that he pointed to and where you might expect an edge effect but unfortunately in the pics he presented in both videos there were almost none with similar areas to substantiate what he was saying and his one example was certainly nothing like as prominent as your examples you gave

pentaxuser

Augustus Caesar · Friday at 9:19 PM

I tried some FX-1 about 2 years ago. FX-21 is far superior.

John Wiegerink · Friday at 11:30 PM

Augustus Caesar said:
I tried some FX-1 about 2 years ago. FX-21 is far superior.

How close in end results is FX-21 to FX-39II? I just bought a couple of bottles of FX-39II to try with Delta 100 4X5.

pentaxuser · Saturday at 12:13 PM

Based purely on the two videos by John Finch the attractions of FX1 seemed to be

1. Extremely low cost, simplicity of making it combined with ease of obtaining the ingredients

2. Great sharpness of detail

3. Speed enhancing (FP4- at 200 instead of 124)

There appears, to me at least, no contentious points in 1 so its a question of what problems arise with enlargements greater than say 5x7 in 35mm negs and greater than 8x10 in 120 negs and of less importance FX1's speed enhancing, if any, properties

It is really those questíons and answers from FX1 users that interest me

pentaxuser

Milpool · Saturday at 12:46 PM

Developers of this type (derivatives of Beutler and such) which operate more or less on the principle of exhaustion, can often result in some “compensating” action (ie reduced highlight densities/contrast). That can potentially lead to an increase in EI because the shadows are able develop more fully without runaway highlights. As I’ve said before, EI can be defined arbitrarily. If someone chooses an EI of 200 for FP4 developed in FX-1, that’s up to them. It seems a little exaggerated to me, but everyone has to decide for themselves. The important distinction is between EI and film speed. A real speed of 200 is not going to happen with FX-1.

pentaxuser · Saturday at 2:33 PM

Can I ask, Millpool if you also have any observations on the last bit of my #32 namely " so its a question of what problems arise with enlargements greater than say 5x7 in 35mm negs and greater than 8x10 in 120 negs?

Thanks

pentaxuser

Alan Johnson · Saturday at 2:56 PM

Crawley BJP Jan 1960 p9-10.
"The shadows in any speed increasing developer are slow to gain contrast, and all "speed increasing" developers work by restraining the highlights until this has occurred.........."

In relation to sharpness with the low metol content:
"....the non availability of considerable supplies of fresh developer [metol] has some tendency, more marked with slightly sharper crystalled emulsions, to prevent the image spread due to the infection of adjacent crystals.
This effect can be promoted by reducing the preservative content [sulfite] of the formula to inhibit regeneration of the developing agency."

"To produce marked adjacency effects on modern [1961] slow and medium speed films requires a special addition, and even then only certain films will react,....." [ie, he is not claiming that Mackie lines will usually be produced]

Jan 1961 p 41 [He claims an 80% speed increase but only recommends FX-1 for certain films, makes no comment on the speed increase not in this group.]

On close reading his claims are a bit more limited than is sometimes attributed to him or what has been found by later workers.

Milpool · Saturday at 3:48 PM

pentaxuser said:
Can I ask, Millpool if you also have any observations on the last bit of my #32 namely " so its a question of what problems arise with enlargements greater than say 5x7 in 35mm negs and greater than 8x10 in 120 negs?

Thanks

pentaxuser

Did that come from the linked video? Or maybe it was in Crawley’s writings? This type of developer will tend to be rather grainy. I can only speculate the assertion regarding limiting of magnification has mostly to do with this.

The favourable acutance-leaning attributes of this type of developer bring with them penalties (you can’t have everything). While they are formulated to give the overall impression of sharpness, the resolving of fine detail can be compromised. This in combination with the graininess and possible enhanced edge contrast effects can potentially add up to an overall “harsh” look as magnification increases.

pentaxuser · Saturday at 5:22 PM

Milpool said:
Did that come from the linked video? Or maybe it was in Crawley’s writings? This type of developer will tend to be rather grainy. I can only speculate the assertion regarding limiting of magnification has mostly to do with this.

The favourable acutance-leaning attributes of this type of developer bring with them penalties (you can’t have everything). While they are formulated to give the overall impression of sharpness, the resolving of fine detail can be compromised. This in combination with the graininess and possible enhanced edge contrast effects can potentially add up to an overall “harsh” look as magnification increases.

If that refers to my quote, the question came from me alone and was asked because John Finch makes no reference to what size of print may be possible with either 35mm or 120 film before the drawbacks to which you refer are visible to a detrimental extent

On screen, sharpness and detail seemed very good by my judgement but I have no idea what size print was represented by what I saw in the video hence my hope of getting answers from users who make darkroom prints about what size they were able to make from either 35mm or 120 negs

Thanks also to Alan Johnson for supplying information on what Crawley wrote. In that respect what John Finch achieves with a speed of 200 with FP4+ seems in line with 80% increase although in 1961 and had an FP film been one of films he referred to, it would not have been FP4 but would have been FP3. However with what seems the same speed so I presume the same 80% increase applies

pentaxuser

Augustus Caesar · Saturday at 8:14 PM

My experience with FX-1 showed rather distinct lines around edges, rather unattractive. FX-21 far better.

Alan Johnson · Sunday at 11:28 AM

My results with FP4 cine film at EI =100 seem to be as described above, no noticeable adjacency effects round edges, a bit harsh on enlargement.
btw 25 years after the Crawley quotes above, BJP 1986 p100 says under the listing for FX-1, speed increase 1/2 to1 stop and there is no mention of dividing films into groups.

pentaxuser · Sunday at 12:15 PM

Thanks Alan. Is that the cheap FP4 cine film that the likes of Secondhand Darkroom Supplies was selling recently? If so then your pictures from the tree shot to the Wells next The Sea one are clearly from 35mm negs and FX1 developer so is there any way to translate your scans above into an equivalent size or range as darkroom prints?

They look good to me and while afficionados might have a problem with shadows or contrast I suspect that most people's desire when they think of b&w prints are just such pictures .

pentaxuser

Alan Johnson · Sunday at 1:41 PM

Yes it is the film you mention.
When I used to make 16x12 in silver gelatin prints using FX-1 I got a similar result to what you see here and started a thread on how to get more visible sharp edges:

https://www.photo.net/forums/topic/103975-minimal-agitation-with-fx-1-and-beutler/

If you want to see some edge effects I suggest try the recommendation of Sandy King to use diluted FX-1 and semi-stand. In my pic above there is a slight white line between the black roofs and the sky at full magnification.

FX-1 acutance

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