5D2 problem - brite colors oversat...Help!

[tlm]

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I purchased the 5D2 kit that includes the 24-105L lens 7/9/09. I am having an issue with image quality when shooting bright colors. The purple flowers are blurry and "blown out" with no detail. The edge around the flowers almost looks neon, like it's been painted on. However, the stem and leaves have great clarity and detail. The other picture was taken at the exact same settings, day, light, etc. and it is much better. The settings were 1/100, f/22, spot metering, center focus, 105mm. I have taken almost 300 pictures, with many different setting combinations, all with the same result. On different occasions, I have also had the same problem with a red flower and a bright orange sweater, all different settings and lighting.

I sent the camera and lens back to Canon. They returned the camera with this comment: "exact cause could not be identified but it was found that causing inaccurate auto focus from time to time. Electrical adj were made on the AF assembly."
The lens came back with this comment: "exact cause could not be identified but it was found that causing front focus from time to time. Electrical adj were carried out on the AF assembly.

I would like to know if I am doing something wrong or if there is a defect in the camera and/or lens. Please Help!!

[Grimes]

Hi, do you have larger sized pics so we can see better?

If it's really bright out, try lowering the ISO and using a larger aperture than f/22. See how that works out for you. It seems in those two pics you are using an ISO of 640 and 1600, which is way too high for a bright sunny day - set it to 100 or 200 and work from there.

[tlm]

Attached is a larger picture.

I was focused on the flower @ f/11. The stem and leaves are crisp and clear. The purple flower is blurry, over-saturated and out of focus...

I took your advice and shot these at ISO100. I was in the AV mode. As you can see, it did not seem to help.

Tx, I'm looking forward to your feedback.

[tzalman]

Clipping the red channel, especially in flower shots, is a problem in every digital camera. It is caused by the daylight white balance operation performed during the RAW>jpg conversion which doubles the capture values of the red channel. The remedy is to (a) shoot Raw, (b) watch the histogram and reduce exposure if the red channel is clipped, (c) in the RAW converter adjust "exposure" until the preview histogram doesn't show red clipping and then raise shadows and midtones while not changing the white point.
Exactly how this is done differs from converter to converter, so advise us what software you have for more help, if needed.

As regards the focus problems, extreme close-ups have very limited DoF. You may want to go back to higher f/stops, despite what was written above. Also, two other things to keep in mind - it is very easy to move the camera at the moment of exposure and because of the thin DoF to loose focus and be careful when getting up close and personal that you are not closer than the lens' minimum distance.

[JWright]

Attached is a larger picture.

I was focused on the flower @ f/11. The stem and leaves are crisp and clear. The purple flower is blurry, over-saturated and out of focus...

I took your advice and shot these at ISO100. I was in the AV mode. As you can see, it did not seem to help.

Tx, I'm looking forward to your feedback.

Posting that in a pdf is no help. You need to post a large jpg...

[Picture North Carolina]

...it is very easy to move the camera at the moment of exposure and because of the thin DoF to loose focus...

also consider using a tripod to maintain that focal point / camera / subject distance

[tlm]

Clipping the red channel, especially in flower shots, is a problem in every digital camera. It is caused by the daylight white balance operation performed during the RAW>jpg conversion which doubles the capture values of the red channel. The remedy is to (a) shoot Raw, (b) watch the histogram and reduce exposure if the red channel is clipped, (c) in the RAW converter adjust "exposure" until the preview histogram doesn't show red clipping and then raise shadows and midtones while not changing the white point.
Exactly how this is done differs from converter to converter, so advise us what software you have for more help, if needed.

As regards the focus problems, extreme close-ups have very limited DoF. You may want to go back to higher f/stops, despite what was written above. Also, two other things to keep in mind - it is very easy to move the camera at the moment of exposure and because of the thin DoF to loose focus and be careful when getting up close and personal that you are not closer than the lens' minimum distance.

Thanks for the great reply!!

The close up picture is actually a very small cropped portion of the original picture. The focal length was 73mm, the lens is 24-105L. I'm trying to keep everything "mid range" so it should be well within the ability of the lens. I'm attaching the original photo.

As for image adjustments, I have worked on different photos of the same flower with the same problem. The flower is way more blown out than the exposure adjustments can compensate for. I've worked with levels, channels, sharpness, etc. Nothing I have tried seems to be sufficient to "correct" the images. The histogram does show a large amount of red. However, the spikes seem to be clipped on the low key side, not high key. I have also shot in Raw only with the same problems. The attached photo is the JPG version of a Raw+JPG shot. If you will compare with the CR2 photos I have already submitted, you will see these flowers look red, not purple. I have PS CS4.

[The Moose]

Are you shooting RAW or JPEG? When you said many different setting combinations, it seems you're talking about ISO, aperture and shutter speed...

If you're shooting JPEG then it's quite possible that your parameters in the Picture Styles are just pushed all the way up...

Edit: Don't mind my post, you've just posted answering the question before mine :lol:

[tlm]

Here's a cropped pic @ 100% scale of the point of focus. All images in this thread are from the same picture.

[René Damkot]

Overexposed.
Clipped channels.

For Raw: Use ACR 5.4. Set the output color space to sRGB. Press "O to get a highlight clipping warning, "U" for shadow clipping warning. Adjust exposure until clipping is gone. Adjust brightness to get the image brighter again.

To get more accurate colors out of ACR, set "Camera Neutral" in the "Camera calibration" tab. This will (about) mimic Canons Picture style "Neutral". Way better then the default profile. (Adobe Standard)

If you use Lightroom, or set a different output color space in ACR 5.4, the histogram and clipping warning might be deceiving you: Link (http://www.getcolormanaged.com/color-management/clipwarninglr/)
For jpgs: Tough luck, but this (http://www.thelightsright.com/RestoreThoseClippedChannels) might help.

Edit: Opened the image in Photoshop.
There's no profile embedded. That's not good.

If I assign sRGB it looks like it does in my (color managed) browser. Clipping (mostly in the shadows though)
I'm on my laptop screen right now, which doesn't have the biggest gamut...

That lead me to experiment a bit.

I assigned the monitor profile, and it turns out that most of the detail is there, yet it simply cannot be displayed by my laptop screen... Maybe that's the problem you are experiencing as well?

Open the image in a non color managed application (or assign your monitor profile in PS). It'll look quite a bit different color wise, but you will see all the detail that's actually in the image.
You will probably run into similar problems when you try to print the image, but at least you can use perceptual rendering intent then ;)

[Mike-DT6]

My understanding of this kind of occurrence is that it is caused by the flower's reflective properties when it comes to ultraviolet light. Some flowers seem to be very highly reflective when it comes to ultraviolet light and I often get the same thing happening in my photographs.

In certain light, and in correctly exposed and focused photographs I'll get glaring flowers, just as described. In and around the flowers everything will be fine, but the flowers themselves will be glowing and glaring! I have always attributed it to ultraviolet light, but of course I may be wrong. :-)

I find it to be particularly bad with gorse flowers and bluebells.

Mike

[c2thew]

Is there any way you can post the full picture so we can work with it?