[glasbak]

K200/2.5 and A* 200/2.8 share the same optical formula 6-6 (exactly the same formula is used also in K 135/2.5), but A* have ED glass elements.

And that makes quite a difference

[bollicina31]

Heck, I touched a very hot topic,

[8540tomg]

Heck, I touched a very hot topic,

Looks like you may have bollicina.

I have had the SMC Pentax K 200/2.5 for a number of years now and it is an excellent lens. Wide open it exhibits some CA but this is not surprising in an almost forty-year-old design. It is sharp at f2.5 and it just gets better from then on. Is it the best of the lot? No auto focus or auto exposure makes it less desirable than the others for most shooters today. If I were purchasing a new 200mm today I would probably opt for the new DA* 200/2.8. This being said the K 200/2.5 remains the fastest Pentax 200mm ever made. It is sharp, contrasty and has that amazing tank-like K series build. If these factors are added to the mix the K 200/2.5 should certainly be part of the discussion when talking about the best Pentax 200mm optics.

Tom G

[bollicina31]

Yes.




Pretty much. My guess the difference is in the coatings and the glass itself.



Pretty much.



From what I read there is a slight difference (because of the coatings, etc.). I couldn't find the comparison shots though.

Hi, thanks for answers


According to you, the difference in color, but to what?
that difference is?


Thank you

FWIW I've always thought that the CA from the FA* was worse than from the other two lenses, but it might just be a hunch. I also don't like its hood bayonet..

Hi Adam ... mmmm this thing seems to me, that FA*
suffers more than CA.

[bollicina31]

Have you read the Photozone review on the DA* 200, especially in the Verdict section? They are pretty much saying the 200/2,8 design have not been changed for the last 20 some years, and I concur. The main reason that I changed into the DA* is I cannot manual focus easily anymore. Otherwise I found there is very little difference between DA* (slightly better) & A* in IQ, CA & PF. Oh, yes, my DA*200/2.8 often FF.

Pentax SMC DA* 200mm f/2.8 ED [IF] SDM - Review / Test Report - Sample Images & Verdict

I understand, you say that DA * and * are almost similar, as performance
but **** is a bit better.

I can confirm that the AF of my A* is pretty worthless. :ugh:

The DA* 200/2.8 is one of the only *'s that I don't own, so I can't be specific on this lens. But on the other hand: all my FA*'s focus waaaaaay faster than of all my (SDM) Da* on my K-7. Focus accuracy is related to the AF-sensor in the body, not the (prime) lens.

Just to say, that the previous post 'surprised' me...

Well, the DA* 200mm from my experience is no where near the other DA*'s AF (I own the 16-50mm and 55mm), it's wayyy faster. In fact, it's faster than my Sigma's HSM.
It's true though that I haven't tried the FA* 200mm, so my statement could be faulty. I'll revise it.

The DA*200/2.8 and FA*200/2.8 are optically identical.

Both the 16-50/2.8 and (especially) 55/1.4 have a fairly long spam (the have to turn more degrees to go from minimal to infinity).

The focus speed of the 200mm lens (FA* and thus DA*) therefore could seems faster than your other DA*'s because of the very shot focus spam of the 200mm (look at the distance scales of all your DA*'s).

Really, really interesting