[falconeye]

I should have called it 'strange colors' instead of CA I guess.

It is a pitty that there is no established name for this type of color artifact.

I wouldn't oppose to call it CA if not at the same time, people claim that there are two forms of CA: lateral and longitudinal. If they would add a third form, "out-of-focus-fringe", calling it CA would be fine with me.

But as it is now, I think that it adds clarity to the subject to distinguish the terms.


Frank, I had no problem with your usage of the term. I just saw a chance to illustrate the topic using your perfect sample images

[noel]

Kudos to Frank for such a great user review.

The lens does look so much more modern and cool than the previous D-FAs, almost like a 'Limited'. Photos are tack sharp and vibrant.

[Miserere]

I've been in conversation with Paul about the subject (2008 August).
He agrees with what I wrote above. His focussed cross with color fringe against bright background is CA indeed. Color fringes for out-of-focus objects are not CA, though.

Hey Falk,

I'm a physicist too, although my days of college optics courses are way behind me (thankfully! ). I do agree that there should be another name for the OOF colour fringes, and it probably shouldn't be OOFCF However, this effect is not nearly as annoying as Lateral CA, which most lenses exhibit to some extent. My post was only in respect to LCA, not OOFCF. Plus, I wanted to make people aware of Paul's write up.

Now let us get back to hating Frank. He's worked hard to deserve it!

[Lowell Goudge]

They change the aperture blade shape, make it abit curved along the aperture hole

Is the sculpting good enough to stop the starburst that develops at the intersections of the blades, when shooting into a bright point source light. i.e. streetlights at night.

[David07]

It is a pitty that there is no established name for this type of color artifact.

I wouldn't oppose to call it CA if not at the same time, people claim that there are two forms of CA: lateral and longitudinal. If they would add a third form, "out-of-focus-fringe", calling it CA would be fine with me.

But as it is now, I think that it adds clarity to the subject to distinguish the terms.


Frank, I had no problem with your usage of the term. I just saw a chance to illustrate the topic using your perfect sample images

I think some people are calling this out-of-focus fringe "bokeh CA"... but maybe not everybody is agreeing on the definition of the word "bokeh" and its usage... !

[frank]

It is a pitty that there is no established name for this type of color artifact.

I wouldn't oppose to call it CA if not at the same time, people claim that there are two forms of CA: lateral and longitudinal. If they would add a third form, "out-of-focus-fringe", calling it CA would be fine with me.

But as it is now, I think that it adds clarity to the subject to distinguish the terms.


Frank, I had no problem with your usage of the term. I just saw a chance to illustrate the topic using your perfect sample images

CA, PF, all these terms made me confusion sometimes. But I roughly know what you mean. To me I don't really care too much about the funny colors at extreme edges/corners, especially when shooting against backlight. But this out of focus fringe thing is sometimes very obvious when I take macros or closeups. Luckily they are not so obvious when stopped down to F8 or so.

Kudos to Frank for such a great user review.

The lens does look so much more modern and cool than the previous D-FAs, almost like a 'Limited'. Photos are tack sharp and vibrant.

Thanks Noel I have yet taken any real macro w/ it yet. Hopefully I'd have chance to take some over the coming weekend.

Now let us get back to hating Frank. He's worked hard to deserve it!

But you are lucky that it's me who post the review. If it's some guys like Darren or Mousehill and many others here, I think you'd hate them even more ('cause they are far batter photographers than me )

Is the sculpting good enough to stop the starburst that develops at the intersections of the blades, when shooting into a bright point source light. i.e. streetlights at night.

Hmm, this is interesting. I haven't thought about this. Need to test it out and see how.

[falconeye]

I think some people are calling this out-of-focus fringe "bokeh CA"...

I'll adopt your terminology,

- Lateral Color Aberration (LaCA)
- Axial (longitudinal) Color Aberration (LoCA)
- Bokeh Color Fringe (BoCF)

It is not mathematically one of the defined types of optical aberration (*) which is why I replaced aberration by fringe. Of course, less picky people may prefer to call it Bokeh Color Aberration (BoCA).

__
(*) Optical aberration - Wikipedia, the free encyclopedia

[Voe]

Great demonstration photos displaying the IQ of the lens, love the bokeh and the contrast.
I just checked B&H Photo but they don't have it in stock yet. Otherwise I would have pulled the trigger and get it.

[scorpioh]

How about adorama?
21917 Pentax D-FA 100mm f/2.8 Macro WR (Weather Resistant) Auto Focus Lens with Hood - U.S.A.

[Voe]

Prodigital2000 is selling it for $645 instead of Adorama $850. But I'm not very confident with buying from Prodigital2000.

Not sure what to do.

[pcarfan]

Prodigital2000 is selling it for $645 instead of Adorama $850. But I'm not very confident with buying from Prodigital2000.

Not sure what to do.

I've bought from Prodigital and had no problems. They wrapped my lens in bubble wrap and just put it in a padded envelope and not a box, but it came in good shape. Other than that it is a great place to shop.

P.S: Good find by the way, as that is an awesome price for that lens.....

[Voe]

I've bought from Prodigital and had no problems. They wrapped my lens in bubble wrap and just put it in a padded envelope and not a box, but it came in good shape. Other than that it is a great place to shop.

P.S: Good find by the way, as that is an awesome price for that lens.....

There was one and it's gone now.

[Rondec]

I would echo that Prodigital has always gotten me things in a timely fashion without problem. I got the DA 35 and 16-50 from them. Both lenses arrived in good condition.

[pcarfan]

There was one and it's gone now.

May be you can call them , they are based off of Canada.

[twilhelm]

Great review and shots. I've been eying this lens, and actually seeing the round aperture results I believe it moved up my list. Way up.