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03-06-2011, 09:16 PM   #16
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QuoteOriginally posted by stevebrot Quote
That is why I use a Wratten #12 (minus blue...like a deep yellow, but more selective) when shooting landscape with Acros 100.


Steve

Shall we nickname you the Eye Doctor?

Minus blue filter; complements #32 minus-green and #44A minus-red. Used with Ektachrome or Aerochrome Infrared films to obtain false-color results. Used in ophthalmology and optometry in conjunction with a slit-lamp and a cobalt blue light to improve contrast when assessing the health of the cornea and the fit of contact lenses.

Cheers,

Luc

03-06-2011, 10:12 PM   #17
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QuoteOriginally posted by stevebrot Quote
(Explanation...Acros 100 is sometimes referred to as orthopanchromatic, meaning that it has extended blue light sensitivity. This has ramifications when shooting landscape (very light skies) and portraits (tends to amplify skin imperfections). On the other hand, Acros 100 has incredible reciprocity characteristics allowing exposures of several seconds without having to adjust from the meter reading. RR 80s on the other hand has extended red light sensitivity and reduced blue. This tends to darken skies and even out skin tones, but with somewhat unpredictable results for intensely blue objects.)

Wow, did not know that. Wierd thing is, there is this one shot i did with Acros indoor unfiltered in a very redish café and it came out contrasty and looked great. I suppose a more red sensitive film would be washed out. And i always thought orthochromatic was for landscape.

03-06-2011, 11:23 PM   #18
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yes only b&w, I'm taking film class and I will be developing this in the film class. we are going to develop color :/. But I really like having higher quality larger prints and thats why I switched, because 35mm as all of you know when you print larger the quality is lost with 35mm and before anyone had replied I had gotten 6 rolls of tri x 400 as well as a roll of tmax 100
06-07-2011, 06:05 AM   #19
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hey, checking you out man

at first i was wondering why you were getting a 645 55mm lens

i think you will be all set when you get it

however, look at picking up a 120mm macro for high resolution stuff, meaning very large prints

otto

06-07-2011, 08:04 AM   #20
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QuoteOriginally posted by stevebrot Quote
(Explanation...Acros 100 is sometimes referred to as orthopanchromatic, meaning that it has extended blue light sensitivity.
I'd be interested in where you found that information. The Acros data sheet doesn't give values on blue sensitivity that I could interpret in a meaningful way from their spectral sensitivity curve except there is a drop in the relative sensitivity starting at 450nm and peaking at 500nm range which covers a lot of the blue wavelengths. But without numbers I couldn't say if that is higher than most films even with that dip.

QuoteQuote:
Acros 100 has incredible reciprocity characteristics allowing exposures of several seconds without having to adjust from the meter reading.
120 seconds before adjusting 1/2 stop extra of light which appears to be a fixed, one-time adjustment but you also have the film's latitude which can suck up that 1/2 stop if you wanted to ignore it.

Last edited by tuco; 06-07-2011 at 09:24 AM.
06-07-2011, 10:32 PM   #21
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QuoteOriginally posted by ottoburgess Quote
hey, checking you out man

at first i was wondering why you were getting a 645 55mm lens

i think you will be all set when you get it

however, look at picking up a 120mm macro for high resolution stuff, meaning very large prints

otto
Thank you very much for all the help! And yes I shoot medium because I still can't get as high of image quality on my dslr as I can on my 645 or 67!
06-08-2011, 01:12 PM   #22
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QuoteOriginally posted by tuco Quote
I'd be interested in where you found that information.
The Acros datasheet: http://www.fujifilmusa.com/shared/bin/NeopanAcros100.pdf

One might add that there is discussion on the various forums as to what, exactly, the term "orthochromatic" might mean in Fuji's context. I have to admit that I don't see it in the curves, but in practice, I have noticed that light-colored skies are the rule unless I filter. Can't say about skin tones.


Steve

Last edited by stevebrot; 06-08-2011 at 04:45 PM. Reason: Fixed the link
06-08-2011, 02:28 PM   #23
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QuoteOriginally posted by stevebrot Quote
The Acros datasheet: http://http://www.fujifilmusa.com/shared/bin/NeopanAcros100.pdf

One might add that there is discussion on the various forums as to what, exactly, the term "orthochromatic" might mean in Fuji's context. I have to admit that I don't see it in the curves, but in practice, I have noticed that light-colored skies are the rule unless I filter. Can't say about skin tones.


Steve
I guess I need to think about it more. But the dip in relative sensitivity in the blue wavelengths seen in the graph may mean more dense exposure in that area and thus brighter/whiter blues when you make a positve?

06-08-2011, 04:44 PM   #24
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QuoteOriginally posted by tuco Quote
I guess I need to think about it more. But the dip in relative sensitivity in the blue wavelengths seen in the graph may mean more dense exposure in that area and thus brighter/whiter blues when you make a positve?
I don't know for sure. The term is ill-defined. In some circles it means an essentially normal panchromatic curve but with little sensitivity beyond 650nm. Others feel that it mean a steep red cut-off along with with a mild enhancement at450nm. The purported effects are:
  • Darkened reds, but still differentiated from black
  • Brighter sky-lit shadows
  • Brighter/lighter blue sky
  • Darker lips without accentuation of skin blemishes (?!)
  • Enhanced haze with less differentiation of clouds from sky


Steve

BTW...I fixed the broken link above. This has happened a couple of times lately...bug in the forum software?
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