Perceptol

Pete: The third one with the lake is my favorite as the large expanse of the background mountains bring out the different grays. I think # 3 really shows the promise. But more than my opinion, how do you like these, and how do they compare with what you've done without Perceptol? BTW, looked at your flckr and the 20151129 shore scene with the lighthouse is wonderful!!!

I'm inclined to think I need to do some side-by-sides to have a real clue, and also to get a handle on "my" ISO for the film. I've never done this, but there's a first time for everything.
 
Thanks for your comment. My problem is always the scanning. Somehow I lose the mid tone grey gradation and seem to end up with high contrast scans with bright whites and dark darks but seemingly losing all detail. When I look at Giulio and Erik's scans I wonder why I would need a digital camera. When I look at mine, I think that I may have well have used one :bang:

I have similar results and disappointment whatever film/developer combination I use.
Scanner is Plustek 8100 with Vuescan.

Pete
 
Pete B said:
Thanks for your comment. My problem is always the scanning. Somehow I lose the mid tone grey gradation and seem to end up with high contrast scans with bright whites and dark darks but seemingly losing all detail. When I look at Giulio and Erik's scans I wonder why I would need a digital camera. When I look at mine, I think that I may have well have used one :bang:

I have similar results and disappointment whatever film/developer combination I use.
Scanner is Plustek 8100 with Vuescan.

Pete
Click to expand...

This is a common problem and one that is not always understood. The issue is that the scanner you are using has an LED light source:

http://plustek.com/uk/products/film-and-photo-scanners/opticfilm-8100/

This light source emits collimated light (parallel rays) which in turn give rise to the Callier effect, which is responsible for an increase in contrast. So, it's analogous to the difference between using a condenser and diffusion enlarger in the darkroom.

I had exactly the same issue when I used a Nikon Coolscan IV and could never understand why my scans were so grainy and contrasty, more so then when I used my flatbed Epson V750. Now I use a Minolta diMage Elite 5400 for film scanning and the scans are much better.

You can see an example from the Coolscan in my gallery, which gives an idea of the problem i.e. lack of midtones :

http://www.rangefinderforum.com/rffgallery/gallery/776/U776I1500912384.SEQ.1.jpg

One way round this is to increase exposure and under develop your negs to give less contrast but ultimately I think it's best to use a cold cathode light source.
 
Lawrence / Erik: I don't exactly have a scan problem 'cause I've set aside my Plustek for DSLR scanning. Did it on the basis that DSLR scans were a heck of a lot quicker, focused, and the quality much better. I do have a light table underneath and I think it is LED driven, but I've seen this whole bit about scans and LED vs. Cathode... and simply not gone there just yet. But if I may, do I understand correctly that Cathode light is "better" than LED? and in all cases? And if it's not to beg a scholarly dissertation but a matter of a few words, what is the difference? Thanks!
 
roscoetuff said:
Lawrence / Erik: I don't exactly have a scan problem 'cause I've set aside my Plustek for DSLR scanning. Did it on the basis that DSLR scans were a heck of a lot quicker, focused, and the quality much better. I do have a light table underneath and I think it is LED driven, but I've seen this whole bit about scans and LED vs. Cathode... and simply not gone there just yet. But if I may, do I understand correctly that Cathode light is "better" than LED? and in all cases? And if it's not to beg a scholarly dissertation but a matter of a few words, what is the difference? Thanks!
Click to expand...
I usually shy away from saying anything is 'better' or 'worse', just 'different' and it's important to realise that the difference between the two light sources only applies to conventional silver-gelatin film and not to colour film or mono films that use colour technology, such as Ilford XP2.

What happens in effect is that LEDs increase the contrast of the denser areas of the negative, so unless your negative is quite soft it's easy to end up with a situation where the scanner cannot handle the contrast. I think it's for this reason that so many posts on the internet recommend soft negatives for scanning.

What I suggest you try is to overexpose your film by about a stop and then compensate by under developing. It's possible that with the Plustek this will give you a better result i.e. better midtones. I'd also suggest you use a fine grain developer and not something like Agfa Rodinal which accentuates the grain. Ilford Perceptol is perfect in this regard or else, for better film speed, D76/ID11.
 
Do these look better? I've scanned them differently, scanning as greyscale rather than RGB, and outputting as tiff rather than dng file.

Pete

028-Edit.jpg

0282-Edit.jpg
 
Great tones, Erik. I've got 7 rolls of Panchro to shoot, but thought I ought to run a test roll first... Ah.... the stuff the Zonies have me thinking to "try" ...as if. Well, it does improve things I think and perhaps(?) faster.
 
I just put another roll through and it was the nicest scanning film I can remember so, by way of a thank you, Erik, here's a picture from our local agricultural show. The Judges were impressed by the Anus Milking Machine ;-)

013 by Pete, on Flickr
 
Basic ISO question for Perceptol: Are you shooting at box speed, or cutting ISO by 1/3, 1/2, 2/3 or 1 full stop? Barry Thornton recommends a cut, and Erik's Tri-X 400 was shot at 200... which doesn't mean that's a norm, but the suggestions to cut ISO mean putting my first roll through of FP4 shot at box speed shouldn't be a first choice... but rather go out and shoot something new. Curious what you're doing in more general practice? Bergger at box speed, too or not? Thanks!

Pete: Love the grays in that shot! Thanks for posting it.
 
In the January/February 2002 issue of Photo Techniques, the late Patrick Gainer published his findings for adding salt to D-23. He found that mixing 50 grams/liter of canning salt - the kind with no additives - gave smoother grain and slightly improved the resolution without loss of shadow detail when using his formula straight rather than diluted. Using the then-available Freestyle version of Delta 400, he also found there was no loss of film speed. He did increase his development time from seven and a half minutes to eight and a half minutes at 68 degrees F.
D-23 with salt is very similar to a once-published homebrewed version of Perceptol. When I can find that again, I'll add it here.
On Sunday, I mixed a couple of liters of this. I should be able to try it later this week.
 
presspass: Thanks for posting this. Glad to know I wasn't losing my mind. Seems I find something and then struggle to re-find it on the web. And think some of those were articles or posts from Patrick. Sorry to hear he's moved to the other category ("late"), but that's probably old news. So which are you trying? D-23, Perceptol, or both?

Seems to me to be worth a side-by-side? Funny that from what I've read (so far), Barry Thornton never gave D-23 much of a whirl as much as he obviously didn't shy from homebrew. His Perceptol 1:2 dilution which Erik seems to use and recommend as well seems mid-point between the more typical recommended 1:1 and 1:3, but time adjustment isn't clear to me - since I hesitate to assume it'd be linear. Futher, it's possible that Thornton was intentionally recommending under-development by 10% or so... in which case his 11 minute recommended time.... ah... gonna have to re-read that in more detail to make sure I understand it.

Unlike Erik, I'm not using 23-C but more commonly 19-C or 20-C so time conversion is pretty much a key part of the developer spreadsheet I keep. Life will get simpler when I settle on a developer and quit squirreling around with trying this and trying that. Not ready for that quite yet as HC-110 and Pyrocat-HD have been very dependable and the latter's results quite likable - even if they toxicity puts me off. The metol-only (no hydro) chemsitry ...if I'm reading it right, makes both D-23 and Perceptol considerably less toxic than either HC-110 or Pyrocat-HD... and merits more work on my part. Not going to push into caffenol... but I do want to worry less about the chemistry I have around me WITHOUT sacrificing results. Who doesn't?
 
In my notebook I have the following recipe for Perceptol

500ml distilled water @ 120F
5g = Metol
100g = Sodium Sulfite
30g = Sodium Chloride (not table salt)
500ml cold water

Not sure where this came from and I have never actually mixed it up and tried it.
 
Roscoetuff - D-23 has been my standard developer for a number of years. Sometimes I dilute it, sometimes use it straight and replenished (not, obviously, from the same bottle). Years ago I tried Gainer's salt formula, and I'm going to try this again. The DIY Perceptol formula I was thinking of is the same one Pioneer posted above. I will probably stick with D-23 since I don't want to lose a stop. I've finally realized that I should just use D-23 straight and toss it. I only do two to four rolls a week now, so the replenishment regime is silly. I will let you know how D-23+salt compares with the regular stuff, both in scanned use and wet prints.
 
presspass: Sounds good to me, and much worth investigating. Thanks for your candor and help! And I absolutely agree with you over not wanting to lose a stop... if I don't have to! I'd be willing to supose that Barry Thornton's 30% devotion to Perceptol had something to do with the available light required by his exposures. I'm willing to have more than one developer... as a differentiated pair is understandable. But using only one and always losing a stop is more than I'm ready for at the moment.
 
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