Acros 100 question

[willscarlett]

I was browsing around on www.fotoimpex.co.uk last night and under their section for Acros 100, they said

it's an orthopan film. I'm just wondering if it really is orthopan or just regular pan film...I've heard the

Acros 100 gives a different look, but have never seen it listed as orthopan before.

[leicaglow]

It is not Orthochromatic, nor does it even look or behave like it. It does give an interesting look, especially for whites. It is extremely sharp. I find it very difficult to process correctly however, and after years of using it (since it came out), I'm not finding a developing solution that gives me the results I like. It's not that I can't get decent images with it, but I guess I feel it can produce better results than what I'm getting. It can be difficult to control the contrast and tonal range in my experience.

[willscarlett]

Hey, thanks for your reply, but the blurb didn't say it was orthochromatic, it said it was

orthopanchromatic. What do people think about the Acros 100 and orthopan status?

[jonathan_traupman]

Looking at the spec sheets for Acros (available on Fuji's web site), it's spectral sensitivity extends to around 625-650nm, which is more or less typical for a panchromatic film.

 

"Orthopan" sounds like marketing BS to me.

[stefan heymann]

This <a href="http://www.fujifilmusa.com/JSP/fuji/epartners/bin/NeopanAcros100.pdf">Data Sheet from Fuji</a> says it on the first page: 4. Color Sensitivity: Orthopanchromatic.

[jay_de_fehr]

JP,

 

Orthopanchromatic is just another term for panchromatic.

 

Michael,

 

I've been using a lot of Acros lately, and find it very good natured with the developers I use. The characteristic curves are very straight, with a slight upturn at either end. Of course these upturns occur outside the useable portions of the curves, so have no impact on imaging. I'll attach a curve made with Acros and GSD-10.

 

Jay

[stefan heymann]

<p>I have learned that Ortho*pan*chromatic has a reduced sensitivity for red light whereas Orthochromatic is red-blind. Panchromatic "sees" red as it does for the other (visible) colors.</p>

 

<p>The <a href="http://www.fujifilmusa.com/JSP/fuji/epartners/bin/Neopan400.pdf">Data Sheet for Fuji Neopan 400</a> states: Color Sensitivity: Panchromatic (also directly on the first page). So there must be a difference in the sensitivity for red.</p>

[jira]

<p>I was recently reading a book, where this was explain to some extent so I can contribute.</p>

 

<p>There is no standardized nomenclature on what should be called "panchromatic" and what "orthopanchromatic". Basically all films are orthopanchromatic eventhough they are sometimes labeled as panchromatic. True panchromatic film would have higher sensitivity to red part of the spectrum.</p>

 

<p>One should look at the sensitivity chart published in the datasheet. Acros sensitivity seems to peak around 550 if I'm reading the chart correctly. This is, I think, where is Acros unique.</p>

[willscarlett]

Wow, it's like we're rehashing the whole chromatic scale of photography here...but yeah, my

general understanding of things was that ortho is entirely red blind, orthopan is more

sensitive to blue than red and pan reproduces the scale in a more natural way, such as how

our eye sees.

[willscarlett]

When I think of orthopan, I generally think of Efke 25/50...altho there are several others, like

the Rollei R3 and some of the high resolution document films

[neil_grant]

The characteristic curve of Acros as posted is incomplete. We don't see what the response

is like outside the straight-line portion. This could be significant if the film is less than

optimally exposed - eg up or down rated.

[User_502260]

If you wanty to simulate the ortho look you can just use a green filter on panchromatic film. For people who have problems getting the best results from ACROS I can recommend Fuji Microfine developer. It is available from the megapearls.com website. Undiluted Microphen also gives nice results with ACROS.

[willscarlett]

Well, that's interesting news...the green filter converts orthopan to ortho and pan to orthopan

[Alan Johnson]

J-P, there is an article re your original question in German. It may be found by a Google search for Wollstein orthopan and use the translate function.I believe the Maco PO 100c mentioned is no longer available.

[stefan heymann]

<p>You mean <a href="http://www.schwarzweiss-magazin.de/swmag_wollstein_28.htm" target="_blank">this one?</a>. It's about Acros and Maco PO100c, both orthopanchromatic films. It's a bit long to translate but if you have any questions arising from an automatic translation I'll help.

 

<p>There's the photo of the girl at the river at the bottom of this page: The jacket is glaring red, the tights are dark blue. With a panchromatic film, the jacket would have been rendered a lot lighter. As it's an orthochromatic film (PO100c), the jacket is dark, but not completely black. The skirt is somewhat darker than a gray card.

 

<p>About Acros, Wollstein says: "Fuji Neopan 100 Acros is a great film that gives extraordinarily high resolution, detail and fine grain. The differences to usual pan films like Ilford Delta 100 or Kodak T-Max 100 are very small. To my understanding of the term, this is not an <i>ortho</i>panchromatic film." [unauthorized translation from me]

[willscarlett]

Alan and Stephan,

 

Thank you for your replies. I'll take a look at the article when I get home from work.

 

I'm trying to understand how a green filter turns pan film into orthopan. Orthopan has more contrast than pan and I thought that with pan films, red filters gave the most contrast. Does a green filter give a lot of contrast too, just that it lightens/darkens different colors to create that contrast?

[robert_grasing]

Have you read Paul Butzi's comments on Acros vs 100TMax color rendition?

 

http://www.butzi.net/articles/tmxacros.htm

 

When Acros first appeared, Fuji published a slim book about it and other film, paper products. I did not buy it: it was too expensive for information that should be distributed for free. I do remember Fuji included a color photo (a fruits, flowers, vegetables sort of still-life) with contrasting B&W renditions on Acros and the older, traditional SS emulsion. Fuji claimed Acros gave the more realistic depiction.

 

100TMax and Acros seem to have a built-in light yellow filter when compared to, say, SS or Plus-X. Perhaps this is part of the meaning of 'orthopan'.

[User_502260]

A green filter does not turn panchromatic film into ortho film. What it does is darken the tones of red subjects. The red subjects look darker in the final print than they would otherwise. If you do copy work with black & white film and if some of the material you are copying has different colors then it is helpful to have a set of colored filters. This way you can separate the colors better into black, white and gray tones. All panchromatic black & white films have slightly different renditions of the same colors. This might be important for scientific purposes or even for artistic ones but for general picture taking the differemce aren't very great.