Can anyone tell me what causes this?

[Keith]

I shot a few pics withe RD-1s tonight at a gallery opening after I'd finished with the work side of things. I figured it would be a chance to try the camera with the 50mm C Sonnar and see how it went with the effective cropped 75mm focal length as a tightish portrait taker.

These are straight out of the camera (RAW) and as you can see the areas of high exposure are blown out and pinkish which indicates to me there was a light source coming from somewhere that the sensor wasn't happy with. Most of the shots seem to be affected in various degrees wherever there are highlights. Is this just something out of the ordinary caused by an unusual light source or is the sensor suspect?

I meant to mention I was under some halogen downlights at the time.

[Keith]

I also meant to mention I use my D700 in this area all the time and have had no issues at all.

[jsrockit]

What ISO were you using?

[FrankS]

The effect looks like posterization.

[ruediger]

To me this looks like the highlights are way overexposed and your raw converter trying to bring some of them back (IMHO there is no such thing like a straight out of cam raw). So for an unclipped color channel that is OK, but for those which hit the maximum you can not do much and that can cause this kind of posterization. This effect might increase with high ISO as with higher ISO the manageable subject contrast range decreases. That your D700 can handle this is probably because in terms of dynamic range the D700 is a monster compared to 2004 tech built into the R-D1.

Cheers
Ruediger

[Keith]

Originally Posted by jsrockit

What ISO were you using?

ISO 800 and I've just gone back and checked on some photos a took a couple of weeks ago also under artificial light and they're the same but not quite as bad. They were at ISO 1600.

This is one of the pics from then. I hadn't notice the effect around her neckline because I converted the image to black and white before making any other adjustments!

[Keith]

Originally Posted by ruediger

To me this looks like the highlights are way overexposed and your raw converter trying to bring some of them back (IMHO there is no such thing like a straight out of cam raw). So for an unclipped color channel that is OK, but for those which hit the maximum you can not do much and that can cause this kind of posterization. This effect might increase with high ISO as with higher ISO the manageable subject contrast range decreases. That your D700 can handle this is probably because in terms of dynamic range the D700 is a monster compared to 2004 tech built into the R-D1.

Cheers
Ruediger

I understand that the dynamic range of the sensor is limited so I shouldn't expect too much but why the pink blowout in the over exposed areas under artificial lighting but not if if I overexpose in natural light? I checked an image I'd taken in a darkened room a couple of weeks ago where the light from a window was deliberately blown out (as I'd expected) but it was colour neutral ... not pink. Or is that to do with the base colour of the subject material ... ie skin?

[back alley]

i have never seen that before...i shoot at 800 often.

[ruediger]

Originally Posted by Keith

... Or is that to do with the base colour of the subject material ... ie skin?

I think it has to do with both, the quality of light and the subject material. The spectrum of an artificial light may be pretty odd compared to natural light. So it might also be the case that the raw converter had to push white balance to the edge and that may also cause such kind of behavior. But I must admit, I never saw it THAT drastically as in your image. What is probably worth a try is to play around a bit with the white balance and see if the tonal values - although not color correct - come back into place. Then you may be able to do at least a b&W conversion without posterization.

Cheers
Ruediger

[Sparrow]

... perhaps it's a temperature thing, and it was just too cool at the time ...

... I'll get my coat now

[roundg]

What raw software did you use ?
Have you check jpg from the camera ?

[Keith]

Originally Posted by Sparrow

... perhaps it's a temperature thing, and it was just too cool at the time ...

... I'll get my coat now

You couldn't resist that could you!

[Keith]

Originally Posted by roundg

What raw software did you use ?
Have you check jpg from the camera ?

I'm using ACDSee Pro and I don't have a jpeg as the camera's set for raw output only. You can see it on the LCD when reviewing though and I gather that's a jpeg generated in the camera.

I think it was the lighting ... these lights they use at QUT are pretty intense and play havock with the white balance on the D700.

[Sparrow]

... it was difficult; I must admit

[gavinlg]

Keith I think you may still have my email address - feel free to send me one of the raw files and I'll put it through aperture/lightroom and see if it does the same if you like.

[astro8]

Never seen anything out of mine even approaching that.

[Keith]

Originally Posted by gavinlg

Keith I think you may still have my email address - feel free to send me one of the raw files and I'll put it through aperture/lightroom and see if it does the same if you like.

Thanks Gav .... I'll send it in the morning.

Actually I just remembered I have Lightroom 2 on my computer and I checked the images .... they're fine!

So the problem is the raw converter in ACDSee Pro ... bloody hell that's my favorite post processing software!

I won't send that in the morning then!

[Spyro]

other than that they look good in terms of sharpness, noise and oof areas
enjoy your camera keith

[FrankS]

I'm so satisfied with my M2.

[Keith]

Originally Posted by FrankS

I'm so satisfied with my M2.

Bloody digital madness Frank.

Guess I'll just have to get used to using Lightroom .... I think ACDSee Pro only supports ERF files in the later versions and I'm still using Pro 3. We are now up to Pro 5 but I'm too cheap to upgrade!

[willie_901]

These artifacts are consistent with insufficient bits required to represent the continuous change of the tone of the light. The result is a discontinuous representation. There is not enough data (bit depth) to accurately model the light. The issue could be purely due to digitization limitations or entirely caused by raw rendering problems. It could be the sensor and rendering software just don't work well together. After all, the world-wide usage of the D100 sensor is minuscule by now. It's possible the raw software engineers never bothered to optimize their algorithms for the RD-1.

Image digitization has come a long way since 2002. ISO 800 is only one stop above the system's design maximum.

If the problem was amplified by the raw rendering algorithms. It will be interesting to see if more sophisticated software reduces the posterization. It would be nice if your raw software was ill-suited for the sensor performance because then all you have to do is find more suitable software.

Either way, the cause is using technology that can't handle those challenging conditions.

[Peter Wijninga]

I don't have this problem in ACDSee Pro5. This said, under artificial light the Epson's white balance tends to ho haywire.

[Sparrow]

Originally Posted by FrankS

I'm so satisfied with my M2.

... yep, pretty smug myself

[gyuribacsi]

Keith, I´am a RD1s shooter too and the phenomenas like in your photographs are happening to me too. As Ruediger said, it is caused by the poor dynamic range of the sensor. Avoid situations with 2 -3 f-stop difference between avenrage litten areas and highly litten areas. For my stage-shootings (of bands) I do not use the RD1 anymore. I do it with film like HP5 or Neopan1600 in a M-rangefinder. Try to get a little better pics with the EPSON RAW converter or Lightroom, but both can not solve the sensor problem entirely.
George

[ruediger]

I have never done any stage shooting at all, but with such high contrast ranges I probably would try to underexpose to get the important light areas right and then push the shadows. I am mainly a b&w film shooter and use the R-D1 to get my hands on color. But I am always surprised what you can find in the shadows of digital files. Once pushed noise increases in these areas, but hey, for me Lightroom does a pretty good job, R-D1 noise looks great anyway and once printed most of it is gone. But as I said, never tried to photograph bands on stages.

Cheers
Ruediger