[JMitchell]

The lens arrived today (Tamron 90mm)

Looks quite painfully sharp, and focusses much closer than I expected!
These are the first few test shots...




Not my eye....











Now the only thing I am a little worried about is this:



Do you think this will be a big problem / concern?


JM

[orangepeel]

Originally Posted by JMitchell

Now the only thing I am a little worried about is this:



Do you think this will be a big problem / concern?

With ACR you can easilly fix CA problems in the "Lens" tab.

However it looks more like purple fringing to me meaning it's actually caused by the sensor. In that case there's sfa u can do about it other than desaturate the affected area

Purple fringing is caused in very high contrast areas. Leaves against the sky, building edges against the sky and ususally the concentrated reflection of bright light on shiny metal things.

[Markulous]

Welcome to the macro club, Jack!

Yeah, as Peel says, that's purple fringing. It's a lens/sensor thing (but more sensor than lens!).

Couple of things can be done when setting up the shot: avoid extremes of contrast and expose to the brightest object - which would've prevented it happening here as you've sensor overload from the burned highlights.

Post processing you can always desaturate (with the sponge) along the fringe and, as it's associated with bright highlights, the result is not that noticeable

[JMitchell]

IGNORE (there needs to be a delete button....)

----------------------------
Oops! There is! And I used it - deleting the 2nd post which was the one you decided to leave! Soz!
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[Markulous]

For them that missed Jack's wise words -

Yeah thanks for the replies guys, I'm not too fussed tbh. I mean, with life size magnification you can't expect perfection.
Mark I'm crying by the computer here....you didn't already include me in the macro club


Overall very pleased, now let me loose on some flowers!!!!

[JMitchell]

Originally Posted by Markulous

For them that missed Jack's wise words -

Why thank you kind Markulous. Where is the delete button? 802 posts and I still can't find it

[Markulous]

Only 'The Chosen Few' get a delete button!

[JMitchell]

Originally Posted by Markulous

Only 'The Chosen Few' get a delete button!

Would "The Chosen Few" translate as "The idiots who are more likely to make mistakes" by any chance?

[Markulous]

Originally Posted by JMitchell

Would "The Chosen Few" translate as "The idiots who are more likely to make mistakes" by any chance?

LOL! We never make real mistakes - just little ones to make us (occasionally) seem human!

[JMitchell]

Originally Posted by Markulous

LOL! We never make real mistakes - just little ones to make us (occasionally) seem human!

I can think of a great dig to put in here, but I don't know if it's too mean....

[orangepeel]

Originally Posted by Markulous

It's a lens/sensor thing (but more sensor than lens!).

Sorry to be pedantic but purple fringing is nothing to do with the lens. It's wholly down to the sensor. It's caused by the light from a bright area overflowing into the cells of a dark area. Hence you see it on building edges against the sky etc.

I believe it's a problem that's much worse on CCD sensors than the CMOS sensors on the pro bodies.



You may be confusing it with chromatic abberation which is caused by the lens - it's where the lens is unable to focus the different wavelengths of light to the same point.

As you say, you can sort of fix purple fringing but at the end of the day, the information in those pixels is lost. The same is not true for chromatic abberation.


Sorry about being a pedantic nit but the difference is important to know when it comes to how you fix the problem. Trying to fix CA using the PF method would be a nightmare and result in lost data. Wheras trying to fix PF using the CA method won't work.