[Spock]

I am getting a little frustrated with the speed of my lenses - currently all my lenses have an F4 max aperture - with the exception of my FA28-105 which starts at 3.2. It is a bit hard getting the pictures I want in low light and indoors.

Looking at the current lens lineup - it seems to be lacking in fast wide-normal primes. Sure there are 'fast' pro zooms and telephotos but 2.8 is hardly fast - and the cost and bulk of these lenses puts me off.

You would think the DA and Limited lens range might have addressed the issue but while there are a few fast lenses (ie. 31, 43 and 77), most of the lenses, especially in the normal to wide range are dog slow.

Remember that in the past - especially in the manual focus era - Pentax had a swag of lenses ranging from 28-50mm with apertures of F2 and smaller. Imagine if we had the similar options now for fast lenses for DSLRs in the 18-35mm range?

Trying to get a fast 'normal' lens today requires scouring the second-hand market and having to make do with manual focus.

What a shame Pentax doesn't better serve this market sector.

[Ash]

Yeah, the DA prime lineup may not be the fastest, but I'm guessing that this would be a priority area for Pentax with the upcoming camera models.

In the meantime, we'll just have to settle for f/2.8 for the majority of them.
Perhaps consider the 16-50?

[Spock]

Perhaps consider the 16-50?

I would except it is bulky, heavy (600g) and expensive (AU$1400) and while it may be fine for wediing photography it is hardly what you'd call a discreet lens for unobtrusive recreational photography.

[Ash]

1. Decide for yourself whether weight/size is more important than IQ.
2. You can get a 16-50 for much less from B&H, Adorama or KEH.
3. How much will the lens intrude on subject matter in a recreational setting?

If f/2.8 is fast enough for you, there's always the Tamron 17-50 or Sigma 18-50 - but no WR, SDM or top build quality.

[Spock]

1. Decide for yourself whether weight/size is more important than IQ.

I hear you but I always feel a bit self concious when taking photos with a huge pro-sized lens especially when other people are using point and shoots.

I don't think size + weight = good IQ necessarily. Old, small and lightweight Pentax 28, 35 and 50mm lenses prove that.

Incidentally why is the LTD 31mm F1.8 so heavy and bulky compared to the old metal K, M & A, 28mm F2 and 35mm F2 lenses?

[Rich_A]

Are you requesting primes? I can't see them offering faster zooms. What lenses are you interested in?

[Spock]

Are you requesting primes? I can't see them offering faster zooms. What lenses are you interested in?

Something fast (F2 or better) that would fulfil the function on my K7 DSLR that a 35mm or 50mm used to serve on a film SLR.

[Wheatfield]

Pentax seems married to the idea of compact high quality optics at the moment. The compromise appears to be that small lenses are also going to be rather slow lenses.
To be fair, Pentax has not made a lot of really fast optics in the past. There was apparently a 35/1.4 that was little more than a mock-up and the very rare 28/2. The 50/1.4s, the 85/1.4 and 135/1.8 is about it for what Pentax has ever made for fast primes.
If you are kicking about the 16-50/2.8 being big and expensive, how do you feel about the DA*55/1.4?
I do find it rather inexplicable that after 6 years in the APS-C DSLR market they still don't have a fast normal lens.
The 35/2.8 macro is a fine optic, but at f/2.8 it is hardly fast, and the 31/1.8 is a holdover from the film days, and isn't a "fast" lens either.
I'm not an optical designer, so I don't know how possible a compact 30ish 1.4 lens would be, but it is certainly something that I'd like to see in the line-up.
Just don't expect anything fast to be reasonably priced. Hoya has made i quite plain that the Pentax camera division has to turn a profit, so you can pretty much bank that the good old days of good quality and inexpensive lenses has come to an end.
The pricing of the 55/1.4 and the 60-250 is likely to be the sort of costs we can expect to see for any new optics that they introduce.

[Ash]

I don't think size + weight = good IQ necessarily. Old, small and lightweight Pentax 28, 35 and 50mm lenses prove that.

Incidentally why is the LTD 31mm F1.8 so heavy and bulky compared to the old metal K, M & A, 28mm F2 and 35mm F2 lenses?

I never meant to imply that.

It's simply the compromise of going from a kit lens to something like the 16-45 to going to the f/2.8 wide-normal zooms on offer.

Primes are another story, and Pentax has exemplified that in the FA ltd series.

[little laker]

Just a thought.
It is possible that Pentax feels we don't need any faster lenses, since we can switch to a higher ISO with just a push of a button now.
Which was of course impossible back in the film days, unless you were shooting med formats with exchangeable backs.

[Douglas_of_Sweden]

Well, you have the FA*31/1.8, FA35/2.0, FA*43/1.9, FA50/1.4, DA*55/1.4 and FA*77/1.8.
But I agree that I would also like to see something fast wider than 31 and 35mm (which right now makes me look at some Sigma options, despite that I generally don't like Sigma). And something fast around 90mm (corresponding to a fast 135mm).

But the motivation for fast lenses are smaller than in the past (or so they think), because DSLRs can handle both higher ISO and longer exposure times (with SR) than the film SLRs could.

[kittykat46]

With High ISO on dSLRs getting better and better, the pressure for fast lenses is much less.

Anyway few lenses are really good below f/2.8, the FA Limiteds being an exception, of course...

Its also very difficult to AF accurately below f/2.8.
There are so many threads on this subject here and other forums on auto focus issues with f/1.4 lenses....some could be genuine lens or camera problems, but lots of "Operator Error" as well...

[Douglas_of_Sweden]

With High ISO on dSLRs getting better and better, the pressure for fast lenses is much less.

Anyway few lenses are really good below f/2.8, the FA Limiteds being an exception, of course...

Its also very difficult to AF accurately below f/2.8.
There are so many threads on this subject here and other forums on auto focus issues with f/1.4 lenses....some could be genuine lens or camera problems, but lots of "Operator Error" as well...

Never had any specific autofocus problem with my fast lenses. Of course the DOF is thinner so you get more of the subject out of focus, but that has nothing to do with AF. Probably people are mixing this up.

[Spock]

To be fair, Pentax has not made a lot of really fast optics in the past. There was apparently a 35/1.4 that was little more than a mock-up and the very rare 28/2.

Is it rare? Bojidar Dimitrov's site says the M-version is available used several times per month and the A-version a few times a year.

There was also a 35/2 - with Bojidar Dimitrov's site saying the M-version is available used several times per month and the A-version supposedly once in several years (which seems strange as they seem to come up for sale more often than the supposedly more common A28/2).

At any rate, clearly Pentax used to make fast primes in the form of 35/2 and 3 versions of 50s - which would be the equivalent of producing 23mm/2 and 33/1.4/1.7/2.0 today - something they don't do.

[Spock]

Its also very difficult to AF accurately below f/2.8.

On the contrary, it is easier to focus as the viewfinder is brighter so that focus is easier for both human eyes and electronics.

Perhaps those people experiencing problems with focus are talking about a problem with shallow depth-of-field? (As Douglas said).