[jstevewhite]

I thought ED glass was all hype until I shot with a few of the Zuikos that used it - holy crap, talk about sharp. here's an idea of what I mean: 100mm f2 - miyajima deer, zuiko 100mm f2 | Flickr - Photo Sharing! - not bad bokeh either.

re: Pentax three lens kit, am thinking 15, 31, 77 will certainly do me - i *do* kind of miss the perfect balance of the DA21, but wanted faster. next LBA battle will be trying to justify the FA 20...

Yeah, the Tamron SP 180mm f2.5 (that's one of my favorite lenses) uses two LD (ELD, ED, whatever your brand calls it, it's all "extra low dispersion" ) elements. Interestingly, the Zuiko f2 was the only 180mm lens that beat it (contrast and resolution) at most apertures.

Aspherical elements can have a large impact on sharpness in wide angles, as well.

[zuikoholic]

right - the dream (for me) was always to get hold of the Zuiko 250mm f2; NASA no less called it "the sharpest lens they ever tested." at 4K a pop, it would want to be, too.

[jstevewhite]

right - the dream (for me) was always to get hold of the Zuiko 250mm f2; NASA no less called it "the sharpest lens they ever tested." at 4K a pop, it would want to be, too.

Well, it needed to be sharp for that little bitty film format; the Zeiss and Schneider on the Hassies and Rolleis had more room to breath...

J/K. I loved the Zuiko lenses. Particularly the finish on the focus ring. I always thought theirs was the best of the bunch. The coatings were lovely, too, and of course you can't criticize the images they made!

And though NASA is a far more august body, it's worth noting that one of the magazines said about the Tamron "Nobody needs a lens this sharp"

[GeneV]

Another thing to consider is focus accuracy of the "tests". If the focus is out by a few millimeters, you will start to see degradation of fine detail.
Lens testing is something that a lot of people try, and a lot of people fail at, and can sometimes come up with wrong conclusions because of it.

+1 on that. It is also a reason why purchasing for the ultimate levels of sharpness can be overrated for many purposes. If most of us can't focus to those levels in tests with lots of time, we aren't likely to do it in the field.

[jstevewhite]

+1 on that. It is also a reason why purchasing for the ultimate levels of sharpness can be overrated for many purposes. If most of us can't focus to those levels in tests with lots of time, we aren't likely to do it in the field.

While a lens can have sharpness and lack contrast, it's rare. Typically, a "good lens" is very sharp and contrasty. I'd even go so far as to say "The definition of a 'good lens' is one that is both sharp and has good contrast". You can certainly discuss bokeh, but if that's all you have to talk about, you're discussing two good lenses already.

Certainly there are times when sharpness is *not* desirable - like when you're shooting pix of your 48 year old mother-in-law in harsh light - but you can always make images *less* sharp in post.

I'm not advocating sharpness as the *only* consideration, but if you buy for a max/max of sharpness and contrast, you won't go wrong, and the *only* thing limiting your IQ will be your skill. Which, I presume, one can improve.

[Laurentiu Cristofor]

While a lens can have sharpness and lack contrast, it's rare.

I would say one needs to first define what they mean by contrast. Some people call a lens contrasty when it produces saturated colors. Then there is the microcontrast component of sharpness (the other component being resolution). You can have lenses that produce saturated colors but are not stellar in microcontrast - the kit lenses, for example - DA 18-55 and DA 50-200. Some people will call them contrasty and may perceive them as sharp, but that doesn't mean they are actually capable of resolving very fine detail. And you can also have lenses that produce less contrasty colors but nevertheless be capable of resolving high detail. I find the colors rendered by the Tamron adaptall 90/2.5 macro to be rather muted, but it is a sharp lens.

[jstevewhite]

I would say one needs to first define what they mean by contrast. Some people call a lens contrasty when it produces saturated colors. Then there is the microcontrast component of sharpness (the other component being resolution). You can have lenses that produce saturated colors but are not stellar in microcontrast - the kit lenses, for example - DA 18-55 and DA 50-200. Some people will call them contrasty and may perceive them as sharp, but that doesn't mean they are actually capable of resolving very fine detail. And you can also have lenses that produce less contrasty colors but nevertheless be capable of resolving high detail. I find the colors rendered by the Tamron adaptall 90/2.5 macro to be rather muted, but it is a sharp lens.

I would agree with everything you have to say here. And compared to Pentax glass, I would agree on the Adaptall 90mm re contrast/saturation, but its microcontrast was very good. (We used to call that "contrast" and "acuity" back in the 80's). With the advent of digital, I pay less attention to the saturation of the colors, but that *is* what originally drew me to Pentax; it's very difficult to tell the difference between +5 saturation and a more saturated original image.

[Blue]

Yeah, the Tamron SP 180mm f2.5 (that's one of my favorite lenses) uses two LD (ELD, ED, whatever your brand calls it, it's all "extra low dispersion" ) elements. Interestingly, the Zuiko f2 was the only 180mm lens that beat it (contrast and resolution) at most apertures.

Aspherical elements can have a large impact on sharpness in wide angles, as well.

I like the way this Tammy manual focuses. In fact, I can focus well enough with it that I have it in my lineup where the DA* 200/2.8 would be.

[Blue]

I have to admit that I have wondered how one of those Zuiko 28/2 lenses would perform with a Leitax convertor when compared on a K20d and K-5 with a FA 31.

[jstevewhite]

I have to admit that I have wondered how one of those Zuiko 28/2 lenses would perform with a Leitax convertor when compared on a K20d and K-5 with a FA 31.

Leitax makes coverters for zuiko OM glass? wow!

[Blue]

Leitax makes coverters for zuiko OM glass? wow!

Yes, they have been about a year to a year and a half.

Olympus OM lens for Pentax cameras

I have been looking trying to figure out one to fill a gap with. I am pretty crowed at the 28 to 40mm area though. I have an F 28, DA 35 ltd and DA 40 ltd. Same thing for the ~ 70 to 105mm range.

[zuikoholic]

yeah, but you have to actually remove/replace the zuiko mount (fully reversible, no damage to lens, just a PITA).

the whole lens to sensor plane registration thing is the *only* thing that C*non FF has going for it, IMHO. i could just whack a Fotodiox adaper on the 5D and then switch Zuikos. it was like having a big, unwieldy, false-colour producing digital back for my Zuiko glass.

then i realised that you can't shoot with a camera you don't bring with you cos it's too heavy.

in my work bag right now is a K5 wearing a DA 15 LTD.

[Blue]

yeah, but you have to actually remove/replace the zuiko mount (fully reversible, no damage to lens, just a PITA).

the whole lens to sensor plane registration thing is the *only* thing that C*non FF has going for it, IMHO. i could just whack a Fotodiox adaper on the 5D and then switch Zuikos. it was like having a big, unwieldy, false-colour producing digital back for my Zuiko glass.

then i realised that you can't shoot with a camera you don't bring with you cos it's too heavy.

in my work bag right now is a K5 wearing a DA 15 LTD.

If I wanted to use it on film, I could use it on one of my several K-mount bodies. Like you said, it can be reversed for future collectors. BTW, there is an E-P1 in my bag wearing an A 50/1.2 compliments of Fotodiox.

[jstevewhite]

If I wanted to use it on film, I could use it on one of my several K-mount bodies. Like you said, it can be reversed for future collectors. BTW, there is an E-P1 in my bag wearing an A 50/1.2 compliments of Fotodiox.

How do you like the E-P1?

[Nick Siebers]

Hmmm, 28/2... LBA wakes up and starts sniffing around.