color casts and underexposure?

jano

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Hi,

I've spent the last year learning how to scan with my Nikon CS V. The majority has been b&w, using vuescan. On the occasional color stuff, I'd use a combo of nikonscan and vuescan, and got decent results. Discvered the vuescan advanced workflow, tried it out with some old negs, got even better results. Then tried out some slides, and got pretty good results, too!

So I grew cocky, and on my recent trip to Bodie and Yosemite, I decided to stick to color film, a combo of c41 (reala and k's 400UC) and some e6 (e100vs). I shot the reala at 80. Paid attention to exposure and everything. Got my negs and slides on friday, and shortly after a quick preview, I became depressed: all results were AWFUL -- strange blue casts, look like they are underexposed, shadows blocked up, regardless of film type. See attached from Cerro Gordo (near lake owens) is typical result. This was reala @ 80, shot around 10:30 am with the 25ZM. In cases where I had large, white rock faces in Yosemite, I even added +1 to EV. The few digital color shots I took with the Sony P&S came out great! Photoshop can fix up the color, but soon as I start brightening the image, I do get noise. Similar results in vuescan and nikonscan.

What are the possible causes? I'm thinking the crystal clear skies we had combined with the high altitude could have screwed with my ZI's meter, or even the fillm? Or maybe the camera itself just underexposed everything (I used AE, and made absolutley certain I was on the right iso and right "A" setting -- I came home with only two lens-cap masterpieces :D) Or perhaps there was a problem with the processing? Which would be odd, considering the e6 was developed at a different lab -- it's actually not as bad as the c41.

Thanks for your time,
Jano
 

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jano,

I popped this image into Adobe LightRoom (beta 3).

The first image I modified using the White Balance slider. The LigthRoom, LR, "as shot" option showed the white-balance to be 5000 K. The LR auto white-balance mode choose 7500 K.

The LR histogram did indicate this image is underexposed by about 1 stop.

I made the second image by increasing the exposure by 1 stop and adjusting LR's Tone Curve sliders in a capricious and arbitrary manner.

These adjustments did not add noise to this image.

So, I think your photos can be printed with the appropriate adjustments. I believe they are under exposed, but not by an extraordinary amount. I also think that there is something about your work flow/film that is different from before.



Best wishes,

willie
 

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Thanks Willie. This just takes a few moments to correct in PS, however, why do you think this happened?

How on earth did I end up with possibly underexposed negatives, when I was overexposing them?

You mention there might be something different in my workflow/film, but no, nothing has changed. I've been shooting reala @ 80 all year, and K's 400UC nearly always works well, and my scanning technique has only improved.. until now *shrug*

Actually, the kodak 400UC looks worse than the reala one up there. I'll have to scan a frame as an example.
 
We can only speculate about what may have happened.

There are two effects – underexposure and the strange blue color cast.

Could your baterries be weak? Where the coditions so bright you exceeded the meter's EV limit (unlikely as the ZI maximum is 19 EV)? Did you use (misuse) the exposure lock button?

The color cast is what made me guess something changed in your workflow. But I rule this out now as you are sure nohing changed.

Do the E-6 photos have this cast too?

I have never heard of strong UV (high altitude) giving a color cast. But then perhaps this is why they sell UV lens filters. I must say I would have not used a UV filter in these conditions.

willie
 
Well, the digital snapshots came out fine with zero need for tweaking -- and it has much less range on its meter. I've never used a UV filter, and in retrospect, I should have, just to protect the lenses -- there's so much gunk on my lenses now (it was windy at cerro gordo). It's possible that could be it. The e6 has a slight blue cast, yes, but not as bad as the others. E6 were all taken at Mono Lake.. which incidentally was the lowest area altitude-wise.

Hmmm. *shrug*
Jano
 
Jano,
Sorry I havne't responded to your PM yet, but since you started a thread...

I honestly have no clue. I have never seen that before. Blue cast? On the slides, maybe, as that can attest to the color temperature of tha tmoment. But the c41 is throwing me. The UV might have affected it, but not that much.

This one has me stumped.

allan
 
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