R-D1 flower pictures get strange aura

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I often snap shots of the scenery here in Japan and have noticed a trend. When I take shots of flowers with the R-D1, I get weird transitional 'aura' between certain colors - particularly in areas that should show a smooth bokeh. for example:

4084875382_9bedfab937_b.jpg


In the upper right, this is particularly apparent. The photo was shot at ISO 200 - likely at 2.8 - with a Hexanon 90/2.8. The effect is present in RAW files and I have experienced it with other lenses. Appears in Epson Photoraw and Lightroom alike. I only notice it when shooting flowers.

Aside from shooting B&W or with a smaller aperture, I'm at a loss as to what I can do to avoid this. Any help would be appreciated.
 
doh! I don't want to hear that.

Frankly, I was expecting someone to tell me to use film... or to stop shooting poor innocent flowers.
 
UV and/or IR sensitivity? With a lot of early sensors purple flowers in sunlight would come out blue, for example.
 
I noticed this to also occur with orange and yellow flowers on a prior outing with a Nikkor 50/2. [That's not to say you're incorrect - the color balance is cooler than a Canon 20D, for example.]
 
This lens has probably not the smoothest bokeh available but it looks quite good as is and i don't see anything wrong either.
 
This effect might occur if the sensor cells responsible for one color are saturated while the others are not.

To rule this out, try under-exposing some shots.

You also might want to separate the image into its three color channels in order to see in which one the highlights are blown.
 
try reducing the mid-tone contrast. I see this in oof areas in black and white conversions i do in silver efex when i turn the mid-tone contrast (they call it structure, some call it definition, or whatever) up too high.
 
way too high saturation is causing it (if not ir sensitivity or other digital sensor trick).
Could even come from wrong color space used. I.e. you shoot or convert the image in(to) adobe rgb and then tag it as srgb.
Or maybe the other way around, can't remember now:))
 
The first thing I would suspect is sensor-based, i.e. UV or IR issues. I would try shots with and without a good UV filter first, and see if that affects the images. If not, then try an IR filter; I realize that is more problematic because only M8 owners are likely to have an IR filter lying around ( :D ), and there are different IR cut filters available. Another option might be to pick some flowers and photograph them against a neutral/white background, indoors only strobe lighting. I'm not sure this would eliminate all chance of UV sensitivity, but it would be worth a try.

If none of those experiments eliminate the issue, I would see if a friend with an M8 or M9 could help out; do some shots on both cameras with the same lenses, composing to account for the crop factor as well as from the same camera position.
 
Thanks for all the input so far. For what it's worth, that shot was taken in RAW and converted using default Lightroom settings, defaulting to the camera's AWB settings. The R-D1 was set for Adobe color space, but had no IR filter. Lightroom settings were at default import values (I have not tweaked them as I am still learning the application).

Thus far, I have not tested lenses with and without IR filters (I do have them for some of the lenses, but alas, not all) I'll give that a shot - as well as some lightroom settings once I fully wrap my head around this application's options. At first blush, it appears that the problem lay in the blue channel and if I set the white balance to sunlight, it goes away (and along comes a world of hot-pink).

4088835443_11602ec74b_o.jpg

This is sunlight setting, exposure brought back to 0, temp 5500, tint 0. Halo not visible. I suspect the correct white balance will only look correct if I invest in some UV/IR filters.
 
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