[RiceHigh]

Fully, on the optical performance! I don't rate anything about the "handling" as I think that this is really not important when compared to the image quality!

Well, since everyday people keep asking about which Pentax lens(es), I decided to write up a quick summary on what I think about the optical quality and performance of my current Pentax AF lenses (12 nos. of F, F*, FA, FA*, FA Limited, FAJ, DA & DFA), which I have used for more than three years (except for newer models which have not been marketed for so long) on my various Pentax DSLRs (namely, *ist D, DS and K100D).

Indeed, there are various aspects to consider when we talk about the optical performance of a lens. Most novices often concern about how "sharp" a lens is. But actually, there are many more factors to concern for a good lens and "sharp" is actually something which cannot be clearly defined: Does "sharp" mean high contrast and/or high resolution and/or even other things and so on?

Hence, I select the following aspects which I consider to be of prime importance for what a lens should perform, as my ratings, namely: Resolution (centre and corners), Contrast (Macro and Micro), Colour Accuracy, Saturation, Distortion, Bokeh, Flare Control, Chromatic Aberration, 3-Dimensional Feel and Exposure Accuracy.

Do note that I have not put Vignetting as one of the concerned factors as I found that the effect is minimal for APS-C sized CCD/CMOS DSLRs and I don't think it should be bothered in most cases.

So, why are the ratings "Subjective"? It is simply because all these ratings are made based on my personal experiences but not measured by some testing procedures. Despite of this, I have actually tried to make each of the ratings as *Objective* as possible. Indeed, I have put down each of the marks by my best judgement, very carefully, and I added up all these for each lens only after I have finished making all the marks.

After I had added up all the marks, I ranked all these lenses too!

Okay, here is the complete rating table!

RiceHigh's Subjective Ratings on Pentax Lenses on Pentax DSLRs

By looking at the above summary, what I can conclude include the following:-

1. Zooms are by no way can match the quality and performance of Primes, optically!

2. Newer Pentax lenses are not as good as older ones, no matter for primes and for zooms!

So, enjoy and hope you find my this summary useful! :-)

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Last edited by Toshi; 02-18-2007 at 12:18 PM.

[superfuzzy]

I glanced at the results, and agree that the Pentax-F 35-70mm is a superb lens. I have two of them
I'll have to take a closer look at the others.

[blende8]

Thanks!
Could you elaborate a bit on your statement about the DFA 100?

"Very strange colour response of which the reproduced colours look unnatural and unfaithful under many occasions. The colour rendition accuracy particularly varies in a relatively large degree depending on the lighting conditions with (slightly) different colour temperatures and/or brightness/exposure levels."

Perhaps with some photos, side by side?

[Jonas B]

Hi RH,
What do you compare them to?

[Alvin]

Very informative. The only thing I would put down in there is the current retail/street price of each lens. I caught myself looking on e-bay for a couple of your very highly rated lenses just to satisfy curiosity - what a shock!

[RiceHigh]

Thanks!
Could you elaborate a bit on your statement about the DFA 100?

"Very strange colour response of which the reproduced colours look unnatural and unfaithful under many occasions. The colour rendition accuracy particularly varies in a relatively large degree depending on the lighting conditions with (slightly) different colour temperatures and/or brightness/exposure levels."

Perhaps with some photos, side by side?

The lens produces unnatural colours which is not pleasing to my eyes nor it is faithful to the original scenes and objects. What makes thing worse is the over-saturated colours it produces make things even worse when the colours are off.

As for pics, I shall post some side-by-side ones (same scene, different lenses) later when I have the time.

[RiceHigh]

Hi RH,
What do you compare them to?

Pentax lens compared to Pentax lenses :-)

Ratings are subjective and personal. But isn't good or bad things are yet having some kind of objective standards? E.g., good colors are good colors, smooth bokeh are good bokeh! .. and ditto for the bad things.

[Jonas B]

Pentax lens compared to Pentax lenses :-)

So I figured. Then I wonder how some ended up as "best" but noone is "worst".

Ratings are subjective and personal. But isn't good or bad things are yet having some kind of objective standards? E.g., good colors are good colors, smooth bokeh are good bokeh! .. and ditto for the bad things.

But I know of no objective standards for measuring or rate neither bokeh nor colors. So it seems all subjective to me.

[RiceHigh]

I have updated my table to add Sigma lenses (as the baseline reference) and also on my Tamron/Kenko Tele-convertors, too. Enjoy and hope you find the info useful!

RiceHigh's Subjective Ratings on Pentax Lenses on Pentax DSLRs