Jump to content

M9 Auto White Balance - work in progress?


wlaidlaw

Recommended Posts

  • Replies 58
  • Created
  • Last Reply

The fluorescent or 'energy saving' bulbs now replacing tungsten bulbs in the E.U. give rise to a lemon-yellow cast that neither AWB nor any 'fluorescent' pre-set seems to be able to handle. Unless I want to use BW or flash, I must white-balance manually. Carrying a folded-up A4 in the bag is a p.i.t.a. and holding it in one hand and the camera in another is even worse. My solution is an ExpoDisc. I ordered it from the manufacturer on Monday and had FedEx delivery on Wednesday -- in Europe! And the thing works very well indeed. An extra bonus is that it can be used for setting exposures by incident light too, which may well make my trusty Gossen Sixtomat Digital obsolescent, with the M9 at least.

 

The old man from the Age of the Minolta Color Meter

Link to post
Share on other sites

Those are fine - actually the lid of a box of Pringles does a good job as well :) It is but one drawback of this new lighting - one of the others is that it gives me a headache :(

The Photographer General has determined that Pringle's may be detrimental to both your cholesterol and your waist. So I do not eat them, and is thus thrown back on the ExpoDisc.

 

LED bulbs are coming on the market. Is their spectral behaviour reasonably predictable?

 

The old man from the Age of Kerosene Lamps

Link to post
Share on other sites

Here is Chris' DNG converted in V5.0.1 Beta.

 

Wilson

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

Well, I got the DNG file, but it's a totally different file LOL!! I'm not sure what I'm supposed to do with it, especially since everyone's face is more or less turned away from the camera...

 

Chris.. did you want me to process that shot?

 

Woops - really sorry. I've checked that this is the correct one - I was going on numbers and misread!

 

Correct one here:

 

http://dl.dropbox.com/u/871768/L1002820.DNG

 

Very embarrassing as the one I posted was definitely a reject! :o

 

Best

Link to post
Share on other sites

Chris,

 

Here we go again. First image straight convert in C1 V5.0.1 Beta. Second one, I have done a bit of local dodging in CS4.

 

Wilson

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

Wilson - this is interesting. I actually don't see any desperate difference between the C1 and LR rendering - but the real problem probably still remains the contradictory problem of compressing JPEG images to show on screen. I KNOW I can print this so that it looks great - shadow detail galore. Scrunch it up to post - or even to FTP to client and it's a problem.

 

Really interesting to see your version - interested to see if it's possible to work out an alternative pre-JPEG default to ensure more acceptable reduced size versions... This is the direction I'm beginning to think about. A bit late in the day I realise - but it's partly to do with the increased potenital we now have for taking images in really low light. I might have a go to see how well the camera handles the JPEGS in-situ. It might be an alternative to RAW in certain light conditions!

Link to post
Share on other sites

Chris--

 

ETA--I just downloaded the DNG....but C1 v5 won't open it up (neither will BreezeBrowser)... so it's corrupted, maybe? Dunno...did you convert it or something in LR?

 

Jaap--get to C1 V5. There, you can adjust individually the colour channels for clipping, so you can actually raise the highlights without them shifting or clipping.

 

Of course, in these shots you need to 1) raise the lower quartertone and 2) lower contrast to get some more shadow detail back (if that's what you like).

 

I wonder--are these compressed DNGs? I wonder if the black point clip level on the M9 is having any affect here (the way the RAW converter converts... )

 

Of course, Jaap, you also have some blown areas in the shots you showed; not much you can do about that...

 

Hey Jamie - that was a good tip:) - C1 V5 is really far better than V4 for M9 files - other handful of $$ gone...:(

Link to post
Share on other sites

Yes Jaap--C1 V5 pro is amazing--better for my D3 too! I've been waiting for that individual channel control for years now; it will absolutely save me tons of time in CC in PS!

 

Here's the quick output from C1:

 

  • set WB
  • individually tweak white point for rgb
  • bump curve for more shadow detail (increase exp about a two-thirds stop overall in the shadows)
  • lower contrast (can always add that back in PS for print)
  • clip wp output at RGB 250 to hold something printable below paper white
  • (I also used the "light falloff" menu to make the light a bit more even on the full-frame M9)

What do you think? I should say I think the M9 profile still needs some work, but nothing like the first M8 profiles :)

 

There's more shadow detail there now, but Chris, you fell "off the earth" with the shadows on the far right-hand side. In PS post, I'd bury them totally. Also, you could burn more of the background to make the speaker stand out in PS as well. A really tough available light shot to get with any camera IMO...

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

See what this looks like on the Forum.

 

Image takes a hammering in 78% quality Save for web.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

See what this looks like on the Forum.

 

Image takes a hammering in 78% quality Save for web.

 

They always do :)

 

I like the overall contrast of your convert--was it from ACR? (I was purposely lowering contrast and saturation to get more detail) but I don't like her orange face :)

 

Here's a finished version (in PS) from the C1 low-contrast conversion:

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

 

To me there's something funky still along the red-green axis with the profile in this shot, but the light source is horrible to begin with!

Link to post
Share on other sites

A number of years ago I had a revelation -- I got to see some original Weston prints. They were of negs made out in the California desert.

 

These prints would have given a heart attack to an average photo contest jury of his time: They had large areas of deep shadow printed to maximum density, totally black. BUT -- the midtones and the highlights sang, and desert heat blasted my face. The images were arresting.

 

In the days of the wet darkroom, we regularly had negs that exceeded the tonal range of the paper by far. All attempts to save detail in the deep shadows, both by overall or local exposure (dodging) led to results that simply did not look pleasing, or even real. I learned to accept that. After that Weston experience, I did even expose my paper until the highlights were slightly fogged, and then cleared them with weak Farmer's Reducer, simply because I had learned how important shadow density was to the final result. Black was not enough. I had to have BLACK.

 

We will only in exceptional cases meet subjects that can be contained within the range of the sensor, and those cases will not be photographically very interesting. We have to accept clipping. The question is, where? Judging and managing that, is a large part of photographic technique, now as then. Trying to squeeze it all in, is not the answer.

 

The old man from the Age of Edward and Ansel (OK, I was just a kid then)

Link to post
Share on other sites

Thank you gentlemen!

 

Lars - your last point highly relevant and wll made. Fully agreed about having to accept clipping - the final issue here was to do with the OVER clipping which JPEG conversion introduced. My interim solution here for very low key images is to make a virtual copy in LR and then impose a pre-set which reduces black clipping to zero and introduces +10 fill light. I'm finding this produces very acceptable JPEGS and has the benefit of not affecting my print-ready editing.

 

Jamie / Rolo / Wilson - looking at the different accounts you've kindly produced, for LARGE numbers of images (I gave the client a couple of hundred shots from the evening reception) I reckon that LR3 is going to be the best raw processor for my purposes (I know the workflow) - but that I can also use LR2.5 for the moment. I am very impressed by the information Jamie was able to squeeze from the shadows with C1 5, although the image was much brighter than I'd want it given the lighting in the original scene.

 

The three heads below give an idea of the issues. My main concern is the break-up in the shadow areas around the speaker's mouth (she's a British MP and Junior Minister, so I want her to look good :)). Again - the PNG's here have exaggerated. What's comforted me here is that the images I was finally able to post looked OK.

 

BTW - back on topic re Auto WB - the image below was from the sound check for a concert in London last night (Steffano Bollani / Antonello Sallis). Both AWB under tungsten. I have no problems with these... The M9 does the business - both with 28 cron asph...

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

Chris, M9 AWB copes very nicely with tungsten and halogen (Brussels has not outlawed halogen bulbs yet). It may even cope too nicely! We do see nearly all light as white when we have nothing to compare with (the so-called colour constancy of our visual system) but a slightly warm cast may not always be undesirable. O.k., easy to correct in PP.

 

As for contrast range, we can often accept an image with both blocked-out deep shadows AND ditto highlights, as long as the mid-tones are really good. Sometimes we have to go that way. To get some extra zing, I finally selenium-toned the print -- another capital offence nowadays. Any modern equivalent to that would probably have to be applied to the paper too, or even the screen, not to the digital file!

 

The old man smelling of hypo

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...