DPChallenge: A Digital Photography Contest You are not logged in. (log in or register) 
 

DPChallenge Forums >> Individual Photograph Discussion >> How do I keep this from happening in the future?
Pages:  
Showing posts 1 - 16 of 16, (reverse)
AuthorThread
 07/11/2004 10:38:51 PM · #1


Other then the purple coloration on the whiskers, I like how this image came out.

What should I do to keep the purple from appearing in future shots? (I plan on photographing the tigers quite a bit in the future.)

Thanks!
 07/11/2004 10:44:57 PM · #2
Hmmm, maybe the whiskers really were purple. Perhaps some medicine or something had been applied?

Otherwise, I have no idea. Sorry.

Cool picture though.
 07/11/2004 10:46:22 PM · #3
Try not to take pictures through coated glass. Just a guess. I would think that the coated glass would keep the reflections from hurted the tigers eyes.

Message edited by author 2004-07-11 22:48:35.
 07/11/2004 10:51:17 PM · #4
The Detroit Zoo has few glass or similarly caged exhibits. There was nothing between the camera and the tiger, save a deep moat and distance...

The whiskers weren't purple either. I was real bummed seeing that.
 07/11/2004 11:05:25 PM · #5
This looks like some sort of chromatic aberration from the lens or possibly a refraction of sunlight from the translucent whiskers. A polarizing filter might help the refraction problem.
 07/11/2004 11:55:55 PM · #6
According to Thom Hogan, "How Digital Cameras Work", the purple fringing is caused by bright high contrast objects.
The pixels in the camera sensor exposed to the bright parts spill over to those adjacent to create a color moire that is very difficult to correct.
Some cameras exhibit the problem while others never have the malady. Personally, I think it is chromatic aberration.
 07/12/2004 12:02:01 AM · #7
something funky happened to me me 2day that might give you some clue. I was trying to shoot these small purple flowers with my 105mm mac lens. It was handheld & for some reason the lens just looked right thru it, making the flowers 98% transparent, giving the BG a purple tinge to it. Either karmat is right on (which is most likely) or there was something in front of it that was purple but the lens just went right thru it.
Recently there was a thread that was about the 300D doing this. A woman took a shot with a fence in front of it, handheld, & in her shot the fence was completely gone.
 07/12/2004 03:17:13 AM · #8
Originally posted by Rooster:
something funky happened to me me 2day that might give you some clue. I was trying to shoot these small purple flowers with my 105mm mac lens. It was handheld & for some reason the lens just looked right thru it, making the flowers 98% transparent, giving the BG a purple tinge to it. Either karmat is right on (which is most likely) or there was something in front of it that was purple but the lens just went right thru it.
Recently there was a thread that was about the 300D doing this. A woman took a shot with a fence in front of it, handheld, & in her shot the fence was completely gone.


The name for this effect is "depth of field." If you have a small/narrow enough nearby object (such as a mesh/wire fence or netting) and focus on a distant point at a wide aperture, the nearby object will become so blurred as to disappear.

-Terry
 07/12/2004 06:21:41 AM · #9
This shot was taken with a tripod. I suppose that I wil have to look into picking up a polarizing filter. (I had hoped that this was something I could 'fix' without having to spend any additional money...)

Thanks for the assistance.
 07/12/2004 07:11:14 AM · #10
The whiskers look quite thin against the rest of the tiger and the lighting conditions are quite harsh. Maybe it's CA? What lens were you using?

Either way, it's not a very difficult thing to fix - just select the area around the whiskers then use the Hue/Saturation tool to reduce the magenta saturation to 0 and fiddle with brightness to make it look natural.
 07/12/2004 07:16:10 AM · #11
Originally posted by PaulMdx:
The whiskers look quite thin against the rest of the tiger and the lighting conditions are quite harsh. Maybe it's CA? What lens were you using?

Either way, it's not a very difficult thing to fix - just select the area around the whiskers then use the Hue/Saturation tool to reduce the magenta saturation to 0 and fiddle with brightness to make it look natural.


Is that something that can be done with Photoshop Elements 2.0? That's the only editing software, besides 'The GIMP 2.0' that I have. Thanks for the suggestion, I will give that a go and see what develops.

This was shot in morning/almost noon-time sun on a Sunny day in Detroit Michigan at the Detroit Zoo.
 07/12/2004 07:25:28 AM · #12
Originally posted by Nelzie:
Is that something that can be done with Photoshop Elements 2.0? That's the only editing software, besides 'The GIMP 2.0' that I have. Thanks for the suggestion, I will give that a go and see what develops.

I don't have Elements, but I do have The GIMP at work..

1) Use the lasso tool to trace around the whisker area. Avoid the tongue.
2) Right click, in the menu choose Image > Colors > Hue-Saturation
3) Select the magenta radio
4) Change the settings to something like: -180 Hue, -4 Lightness, -100 Saturation

Message edited by author 2004-07-12 07:25:41.
 07/12/2004 10:08:35 AM · #13
You can try this method (It works for me most of the time):

Also try the color noise reduction method in Photoshop (RAW Mode).

I tried the CA reduction in Photoshop RAW mode and was not happy with the way it turned out.

Correcting Chromatic Aberrations With Adobe Photoshop

It seems that there are always a few of your photographs that manage to have some "Purple Fringing" with digital cameras. And, of course, it seems to be the ones that you favor the most. There have been numerous technical articles written about the cause of this complaint. The bottom line is that it is an inherent problem with some digital cameras and it normally occurs when an area of a photograph is overexposed. Using software applications such as Adobe Photoshop, it is possible to decrease the visibility of the chromatic aberrations.

.. How To Repair Chromatic Aberrations With Adobe Photoshop
 07/12/2004 10:16:49 AM · #14
Okay. So this has something to do with the whiskers being overexposed.

What should I do to take this shot with less overexposure?

Should I have set the shutter speed to something faster then 1/200th of a second? Would it have been better to play with the exposure control?

I am planning on going back to the zoo sometime this month, hopefully with similar lighting conditions. (ie, early in the day.) I will be spending a greater amount of time shooting images of the Tigers and Lions, instead of a handful of shots from various areas. I want to obtain a few 'classic' Tiger shots.
 07/12/2004 10:40:47 AM · #15
Originally posted by Nelzie:
Okay. So this has something to do with the whiskers being overexposed.

What should I do to take this shot with less overexposure?

Should I have set the shutter speed to something faster then 1/200th of a second? Would it have been better to play with the exposure control?

I am planning on going back to the zoo sometime this month, hopefully with similar lighting conditions. (ie, early in the day.) I will be spending a greater amount of time shooting images of the Tigers and Lions, instead of a handful of shots from various areas. I want to obtain a few 'classic' Tiger shots.


Looks like Chromatic Aberration to me. Usually the purple tinge will go away if the lens is stopped down a couple of stops.

Of course, this will require a slower the shutter speed, so you may have to worry about blur.
 07/12/2004 10:41:17 AM · #16
Originally posted by Nelzie:
Okay. So this has something to do with the whiskers being overexposed.

What should I do to take this shot with less overexposure?



Bracketing would be something to do. You could use AEB (auto exposure bracketing) as described in your manual or do it yourself by taking several shots with different exposure settings. Take note of what exposure setting you used for each so when you get them in the computer you know which one's which. EXIF does not tell you if a shot was over or underexposed except maybe when using AEB.
Pages:  
Current Server Time: 09/10/2025 07:15:58 PM

Please log in or register to post to the forums.


Home - Challenges - Community - League - Photos - Cameras - Lenses - Learn - Help - Terms of Use - Privacy - Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 09/10/2025 07:15:58 PM EDT.