City View from the Highest Home in Albuquerque
Click the image to view this scene interactively
The view from the Patio of the Highest Home in Albuquerque, New Mexico, USA
Here's the link to the rest of this home that's for sale for $2.9 million in Albuquerque
http://www.elitehomespecialist.com/ipix.htm
Re: Chromatic abberation
Aldo
Where did you see the chromatic abberation?
I usually don't get them on bright outdoor shots.
Douglas Aurand
Albuquerque, NM
Re: Chromatic abberation
Just about everywhere... The most obvious areas are the shadows of the deck-chairs. Once you have spotted the CA there, you will see that almost all contrasty edges show similar discolorations. Same with your 'Downtown Albuquerque' image.
Even though CA is mainly visible on contrasting edges, it influences the overall sharpness of the whole image. So if you 'fix' the CA, you get a better image. If you keep the focus and zoom fixed, CA should be a fixed 'property' of the lens (I am not 100% sure the aperture doesn't play a role); even if it is less noticable in some images, it's there.
I hope you don't mind the constructive criticism.
Re: Chromatic abberation
Aldo
I appreciate your constructive critisizm. The reason I joined IVRPA was to get better at virtual image photography.
The cause may be Photomatix compositing the images
I see it. The blue tint next to the shadows of the furniture
Thanx
Douglas Aurand
Albuquerque, NM
Re: Chromatic abberation
The blue tint is half of the problem; if you look carefully you will see a yellow tint on the 'other side' of the blue tint. Photomatix may make it more visible, but it is not causing the effect.
If you load your source image in Photoshop, you can see the cause of the colored fringes if you look at each of the 3 R,G and B 'channels' in the Channels palette. If you click one of the channels, you will see a greyscale representation of each separate channel. If you look closely switching between the channels, you will probably see the image shifting and/or scaling slightly when going from the green to the blue channel. That is the problem.
Re: Chromatic abberation
Aldo
I figured out how to see the Channels in my Photoshop 5.5 and I read about Chromatic Aberations on Wikipedia and WikiPanoTools so I understand what they are and how they're caused.
I figured out how to move the color Channel, but I'm not sure how to scale it to sharpen the edges. What do you do?
Douglas Aurand
Albuquerque, NM
Re: Chromatic abberation
Mini-guide, for experimentation:
- In photoshop, select the Channels panel
- Click the blue channel (you are having blue/yellow fringes, so the blue channel is at fault). You should not have a greyscale rendition of the blue channel
- Click the 'eye' of the RGB channel. The blue channel should remain selected, but now you 'see' all channels again
- Press CTRL-A (select all) and CTRL-T (transform selection)
- Now you can start transforming the blue channel by manipulating the handles. Scale down the blue channel by two or three pixels and watch the colored fringes disappear (or see them exaggerate if you go the wrong way). TIP: hold shift to scale proportionally, and hold ALT to scale symmetrically.
I think Photoshop 5.5 still has Edit->Transform->Numeric, which can come in handy too.
Chromatic abberation
I think you will find that if you try to fix the chromatic abberation in your shots, the images will come out sharper. NB: don't fight the sympton, but fix the problem; don't simply remove the colored fringes but do something like scaling/moving one color channel relative to the others to get them to line up better.
When I was still shooting with a Coolpix combo, scaling the red channel really helped in that regard. I had a Photoshop action set up for the task which also fixed the vignetting of the lens. Nowadays I shoot RAW (not using a coolpix anymore) and use Adobe Camera Raw for the CA and vignetting in one go.