Chromatic Aberrations of EF 24mm, because of digital?

[dxphoto]

I recently purchased a brand new EF 24mm f2.8 lens for my XT. After I took a

few test shots, I found noticable Chromatic Aberrations in almost all the stops.

Is it normal? I know it is a cheap lense. Is it supposed to act like this?

Or it is because I am using a digital camera? Thanks.

 

(I have to fix it in PS RAW editor, by set the value for red/cyan fringe to -15)

[john carter]

There is too much multi-level marketing in the photo industry, today . Buyer beware, no matter what company you from which you choose to buy.

[PuppyDigs]

CA isn't a problem with my EF 24 2.8 but it's 16 years old. Is the CA visible throughout the

image or only on blown highlights and points of extreme contrast?

 

Incidentally, I paid $300 for this lens in 1990 and thought that was a lot a bread back in the

day.

[dxphoto]

Hi puppy face, on the on high contrast edges only. Why is that?

[PuppyDigs]

If it's only on the the edges between high contrast borders, it sounds more like sensor

bloom--electrons leaking/bleeding from adjacent photo sites--than CA.

[mendel_leisk]

This reviewer notes "some" CA, about 4 paragraphs down:

 

http://www.the-digital-picture.com/Reviews/Canon-EF-24mm-f-2.8-Lens-Review.aspx

[awindsor]

Photozone tested the 24/2.8 on a XT and did not find bad CA.

 

http://www.photozone.de/8Reviews/lenses/canon_24_28/index.htm

 

You may have a bad copy.

[eugene_scherba]

Hey D! Care to post samples? Some CA may be normal for any lens

under harsh conditions.

[gdanmitchell]

Yes, it seems to me that setting to -15 on occasion to fix CA probably does not indicate a

major issue. I've seen images with certain lenses where a more extreme adjustment was

needed to bring the corners up to snuff.

[act]

Hey D,

 

I've been using the 24mm 2.8 with my XT for about 5 months and haven't noticed any CA. In comparison, under similar high-contrast shooting conditions my 24-85 and EF-S 17-85 often exhibit noticeable CA. Could you post an example?

[rafael_franco]

Quote from D notLast: I know it is a cheap lense

 

I happen to have this lens to and $300 is by no means cheap. Manufacturers must by very happy these days if people thinks a $300 lens is cheap.

[steve_dunn2]

<cite>Or it is because I am using a digital camera?</cite>

 

<p>Chromatic aberration is a property of the lens, not of the body, so if you were to use it on a film body, use a film with the same resolving power as (or greater than) the XT's sensor, and then examine the results at the same magnification as you use when reviewing your digital images, you should expect to see CA there, too. I suspect fewer people noticed it in the film days because fewer people were accustomed to viewing their images at 100%; if you look at a 4x6" print, you'll be less likely to notice various defects.</p>

 

<p>CA is pretty much a fact of life and I'm quite accustomed to fixing it in software (<a href="http://epaperpress.com/ptlens/" target="_blank">PTLens</a> in my case, since I use PS Elements 3 and CA correction is one of the parts of ACR which are disabled in Elements). All three of my zooms (17-40/4L USM, 28-135/3.5-5.6 IS USM, and even the mighty 70-200/2.8L IS USM) show varying amounts of CA at various focal lengths. So did my 300/4L IS USM (particularly when used with the 1.4x II teleconverter; without the TC, CA was present but not very pronounced). I think my 50/1.4 USM does, too, though I don't use it all that much these days.</p>

[peter_langfelder]

My 24/2.8 exhibits some CA when used on my EOS 3 and film. Here are a couple of examples: <a href=http://tachyon.uwaterloo.ca/~plangfelder/AdacksOct05/Peter/AdacksOct05-05-lg.jpg>Example 1</a> and <a href=http://tachyon.uwaterloo.ca/~plangfelder/AdacksOct05/Peter/AdacksOct05-07-lg.jpg>example 2</a> (look in the upper right corner; there's a bit of CA visible on the tree trunks).