Simple question and I figured there may be some legit optics guys here.  

I have an older spotting scope, no mirrors near as I can tell, just a straight through type.  Very high end back in the day.  But the chromatic aberration is *terrible* on this scope.  Lenses are very clean and scope is undamaged and in near new condition.  However I am the second owner and I'm wondering if bouncing around in a truck, etc. (or whatever it went through prior to me getting it), could result in the lenses falling out of alignment?  Everything I read points to only scopes with mirrors (like reflectors and Schmidt and Mak type telescopes, etc) needing collimation.  But I can't for the life of me figure out why this scope has it so bad (I won't mention the brand, but it was probably over $3k years ago when it was new).  I have a $300 Chinese spotter that, next to it, looks like a Wal-Mart Bushnell vs a top-tier Swaro (the Chinese scope is the Swaro in this example!)

Just trying to figure out what I have going on here.  

Thanks.

I'm sorry for the silly question but, what is it exactly that you are seeing that you are calling chromatic aberration???

My understanding of true chromatic aberration is that it is a property of some types of glass (specifically the glass in the optic) and it is not "repairable" or "fixable".  It did not result from any type of mishandling.

Not silly at all, I should have been more clear.  

Purple and yellow color banding around objects, particularly at the edges of things like roofs, paper targets, anything high contrast.  Lights especially (at night) are bad.

I've had some complete garbage Chinese optics, and even they weren't this bad.  Its almost as though the edge won't focus, which is why I was wondering if it could be a lens alignment issue.

The chromatic aberration I have seen is blue/red banding or haloing on opposite sides of an object.  It looks something like this >>>




with the reds and blues (haloing) being most visible although in some examples I can see some pale yellow and perhaps purple as well.  It occurs because the glass (lens) in question bends light of differing wavelength (color) to differing degrees...  optically it looks like this>>>



It isn't "almost as though" the edge won't focus - that's exactly what happens with chromatic aberration...  and the farther you are from the center of the lens, the worse it is...  The only fix that I know of is to replace the glass and/or redesign the optic - which is not generally do-able!...  

It is possible that the optic may also have some alignment issues due to "rugged" use in the past which may be contributing to image quality degradation.  If the optic is a well known brand with a good reputation for customer service, you might consider sending it back to the manufacturer for diagnosing... or alternatively, you might consider introducing the optic to its third owner!...  

Agreed.  Chromatic aberration is primarily a product of optical design.  Components of that are the type of glass used and lens construction - achromatic, apochromatic, or aspheric.  If your scope is older, it likely has an achromatic doublet for an objective, which tend to have limitations for correcting chromatic aberration.  

Hopefully, it still resolves details well, and is usable for its intended purpose.