ASA of Kodak VC 160 ?

[sanchi heuser]

Hi,


what are your experiences with Kodak Portra 160 VC ?
Kodak says in it's technical sheet to set ASA 160 for daylight,
50 for photolamp 3400K, and 40 for Tungsten 3200.

Andi

[Kirk Gittings]

I always found 160 to be overrated. Though I never did an actual film speed test on it. I always shot it at 100 and since I was always doing my own printing and scanning, I was a pretty good judge of what worked. I found that speed gave me much better shadow detail but still retained the highlights.

[sanchi heuser]

Kirk,

thanks for your fast reply.
I'll try with ASA 100.

I don't understand yet why Kodak advises to change the ASA when
the colour temperature gets lower ?

Andi

[Richard Wasserman]

I second Kirk's experience and also expose it at 100 EI.

[Robert Ley]

I think that Kodak refers to the speed with artificial light to be with the proper conversion filter such as 80A with 3200 degree tungsten lights.

[Drew Wiley]

I don't know about tungsten exposure, but for daylight I find box speed to be spot on.
I've done formal testing, and just printed some 8x10 this past weekend, and have
printed quite a bit of it before. ASA 160 for me; but it's academic, since this film has
been replaced with a newer version.

[Ash]

Try my best to shoot 160 film at 100

[sanchi heuser]

Thanks for your feedback.

Yes, this film will be replaced.
But I have yet some boxes here and I was interested in
the speed as a rough orientation.

When I used my last sheet of VC 160 I try the Ektar 100.
The photos from different photographers I saw that are said to made with Ektar 100 had colors that I liked very much.
OK, Fuji color negs are quite cheaper here in Germany, maybe I should test them.

Thus I'm interested in the question of the changing of filmspeed
according to light temperature.
I would like to understand how that works.
Has it something to do with the part of red light that increases
and that has therefor different effects on the film?
I have just looked at a chart,
It says e.g. that the percentage is:
at 2000K = blue 5,8%, green 16,7%, red 77,6% ~candlelight
at 3200K = blue 20,0%, green 30,0%, red 50,0% ~photo lamp
at 5500K = blue 33,3%, green 33,3%, red 33,3% ~medium daylight
at 8000K = blue 39,1%, green 33,7%, red 27,2% ~blue sky

(from the book "Professionelle Beleuchtungstechnik", author Jost J. Marchesi,
Verlag Photographie)


The method I use for exposure control is just to set the film speed at the lightmeter (analog Pentax spotmeter)
and measure the shadow parts that I want to have details in.
I set that value to zone II or III.
I read the time/aperture settings.
Then I measure the light part whith details and see if the range of contrast isn't to high.
If the range of contrast is too high I consider whether to put shadow
from Zone III to Zone II,
or to use ND filter if possible (e.g. sky),
or to sacrifice details in some light parts,
or to wait for other light (most photos are outdoor).


Andi

[keith english]

I'm pretty sure those ASA numbers are with a conversion filter.

[Daniel Stone]

I shoot my 160VC(8x10 and 4x5) at iso 80.

This film has SOOOOOOOOOOOOO much latitude, exposing it a "full" stop over rated speed has proved to be beneficial for retaining good shadow detail

-Dan

[Drew Wiley]

Serious overexposure will affect the color balance somewhat. I won't get into the details or someone will make a fuss without doing their homework. But a damn nice film. I have yet to see how the new 400 Portra compares to it, which is the alleged replacement for 160VC (the new 160 is closer to the older NC). Right now I'm optically printing 20X24's from both 160VC and Ektar 8X10 negs, trying to get a handle on the respective nuances. A bit tricky to evaluate since both films are printing so nicely with so little effort.

[sanchi heuser]

Many thanks for your replies.

The VC 160 negatives showed good results with 100 ASA rating.
I'll post some here when I got them back from the scan service and
tried my luck with photoshop :)

Next film is the Kodak Ektar 100.
I think I try it with ASA 100.

So far
Andi

[sanchi heuser]

Hi all,

the scans of the Portra VC 160 are ready and the results are quite good concerning
the shadows/lights and colors.
I'm editing them right now and post some in the next week.

I ordered two boxes of the Portra 400 today.
Might be an idea to compare it directly with the Ektar 100.

Andi

[Kevin J. Kolosky]

I've used this film extensively for shooting outdoor portraits. If I was shooting on cloudy days or in deep shade I would sometimes have to rate the film as low as 60 in order to get a decent negative. As the light temperature gets lower the full spectrum of the light does not hit the film. If you have less red light the cyan layer doesn't, for lack of better words, become exposed as much. If its really cloudy you might even have to use some red cc filtration.

To test the film I use the status M setting on my densitometer. I used the published suggestion that a gray card should have .85 density through a status M red filter reading. If you don't have a densitometer you should have a lab read it for you.

[sanchi heuser]

Here are two photos I made with the Portra 160 VC.

Enuma
http://farm6.static.flickr.com/5149/5680414775_b8e389edd1_b.jpg (http://www.flickr.com/photos/58013730@N08/5680414775/)
Enuma (http://www.flickr.com/photos/58013730@N08/5680414775/) by andi_heuser (http://www.flickr.com/people/58013730@N08/), on Flickr






Schauspielhaus Düsseldorf
http://farm6.static.flickr.com/5029/5680950940_9cde867e05_b.jpg (http://www.flickr.com/photos/58013730@N08/5680950940/)
Schauspielhaus Düsseldorf (http://www.flickr.com/photos/58013730@N08/5680950940/) by andi_heuser (http://www.flickr.com/people/58013730@N08/), on Flickr

Any comments welcome.

[SW Rick]

Andi,

very nice! I especially like the patterns of reflected light from (I am guessing) the building to the left of frame on the Schauspielhaus Düsseldorf... A nice counterpoint to the real windows

Rick

[Drew Wiley]

Kevin - interesting observation, but the problem seems to become even more serious
with Ektar overresponding to blue. I'm not certain to what degree subject color temp
is involved in relation to the film, and to what extent the film curve related to the output media. I just made two prints barely different in exposure time (only 1 sec difference), all other filtration identical, and the amount of blue in the shadows shifted.
Obviously I was starting to climb the steeper part of the dye curve at that point, but
it's taking a bit more experience to predict it - and 160VC is now being taken off the market, so I start over with whatever - maybe Portra 400. Ektar itself seems to be
the Velvia of color neg films, and you have to be careful how to use it. I'm not sure
overexposing Portra is going to cure the shadow problem completely - it seems to be
an engineering issue in Ektar-ish films in general, and one more example of why neg
films cannot directly replace chrome films at this point. Still, an impressive suite of
films to choose from, and I'm beginning to form a subconscious idea of how the curves
work in the real world. At least, their marriage to the newest Crystal Archive papers
(Type II) is even better than it was with Super C, for those who happen to still print
analog.

[Drew Wiley]

Oh yeah, Kevin - and as you suggested I will again be packing some warming filters
with me for shade work, to see if this helps issues.

[Sirius Glass]

Box speed. ISO 160 and no problems.

If your results are different the either you meter is off or the camera shutter or both are off.

Steve

[sanchi heuser]

Andi,

very nice! I especially like the patterns of reflected light from (I am guessing) the building to the left of frame on the Schauspielhaus Düsseldorf... A nice counterpoint to the real windows

Rick

Thanks for kind words.
Yes, you're right, on the left is a tall building which is called "Dreischeibenhaus" :
http://de.wikipedia.org/wiki/Dreischeibenhaus

Here's a photo from Wiki that shows the scene with the theatre. On the left you can see a little
bit from the high riser:
http://en.wikipedia.org/wiki/File:D%C3%BCsseldorf_Schauspielhaus.jpg
(Picture from Andreas Praefcke)

My camera was placed 5 feet behind the bollards.