[MRRiley]

Just to clarify, by "high end" you mean "large focal length" not "high-end of the market". Because the latter tend to be constant aperture (which is why they're so expensive, really.)

Yes, I meant long focal length. I did mention constant aperture zooms being expensive.

my buddies canon 70-200 USM is a constant f2.8, at around 1500 (i dont remember how much he paid for his)

it makes wonderful pictures

Tokina also makes an 80-200 constant f2.8 unit for pentax, can be had for around 1000-1300 IIRC

what is the insentive for me to buy a 200mm fixed lens in light of other lenses on the market for a similar price? how much higher quality are we talking about here? is it really worth it?

I don't consider 200mm to be "extreme focal length". 300mm is not even very extreme but its where the prices start really going up for constant aperture zooms. I wouldn't frankly buy a 200mm Prime lens at this time because as you say, the XX-200mm zooms work very well at affordable prices.

Don't know about the f8 thing...the cheap(~120$) 70-300 tamron has f/4.5 at 220mm and f/5.6 at 300 and is pretty decent in terms of image quality.

But I bet it doesn't even compare in terms of sharpness, contrast and so on with the new 300mm f/4.

I was speaking in generalities there and didn't have any particular lens in mind. I just pulled common aperture numbers out of my hat.

You bring up the crucial point Raz. In terms of IQ, at focal lengths beyond 300mm it becomes harder and harder for zooms to keep up with fixed focal length lenses. Are there mondo zooms that do the job, yes, but they tend to be very very very pricey. I simply prefer a 300mm f4 Prime to a XX-300mm f2.8-5.6 zoom. This happens to be true on the wide end as well...

Of course there is also the issue of availability. Zooms of any range are much more common than primes of any focal length. You can find 3rd party prime lenses for Pentax but I am not sure if any are in current production, yet all of the 3rd party manufacturers make zooms. Even Pentax is concentrating largley on zooms and less on primes.

All in all these points summarize why I prefer "extreme focal length" lenses to be fixed focal length, aka Primes, rather than super zooms. You can always zoom with your feet...

disclaimer. Just because I prefer primes for extreme telephoto it doesn't mean I don't appreciate extreme zooms. I do want a Bigma (Sigma 50-500mm f4-6.3 - $999) and to get that range I am willing to deal with the variable aperture. Can any of you imagine how much it would cost as a constant f4 or even f5.6? Not to mention how huge it would be? "Bigma" wouldnt begin to describe it.

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Last edited by MRRiley; 01-24-2008 at 04:58 PM.

[Fototim]

can someone fill me in on the merits of fixed focal length extreme telephoto lenses?

is the quality significantly better that for a thousand bucks you sacrafice ability to properly compose your shots?

Fix focal lenses tend to be lighter and more compact than zooms.
And generally speaking they are of much better optical quality.

Tim

[Paul]

I'm not impress with Pentax prices on the long primes. The Tamron 70-200mm F2.8 that's about to be release soon looks so much more tempting now.

[ryan s]

Will we have any price drops coming on the current lenses? IDK how Pentax prices them, since I don't own an AF lens.

The 16-45 is tempting...

[offertonhatter]

I like the look of the 35mm, but it is s shame it is not faster, say F1.8 or even F1.4 (like the limiteds of old) but I suppose they have decided on Macro instead....

[nanok]

(...) You can always zoom with your feet...

with all due respect , no, you cannot. using your feet changes perspective, zooming (reframing) does not, to mention just one _essential_ point. that's why zooms are bad when you start out with photography: they "teach" you to never think about perspective.

to see what i mean, take your standard 18-55, shoot something (some objects layed out on a table, for instance) at 18, step back to frame the same at 55mm and shoot again (make sure you move on the axis of your lens when you shot at 18mm). it will be obvious

just my 0.02$

[code4code5]

The DA 50-200 is also more expensive than the Tamron 70-300 and Sigma non-APO 70-300.
I don't expect the 55-300 to be less expensive than the 55-200.

In Swedish magazines, the Pentax FA J 75-300 has got better reviews than Tamron 70-300 and Sigma 70-300, and it is also less expensive than the 50-200 - so that may be an option if you don't want to pay so much money.

I bought the non-APO Sigma and I am generally happy with it, but I find that I really miss the quick-shift focusing of the DA lenses. I think it is a seriously underestimated feature of these lenses and I would happily pay quite a bit more for that feature. It is easy enough just to switch the AF off, but it's really nice not having to take your hand off the lens. It wasn't until I had to do without it that I realized how much manual focusing I do.

[nanok]

i subscribe. i have been thinking about the sigma 17-70 for months now, but can't bring myself to get it instead of the 16-45 for instance (allthough i like and need the extra range on the long end), exactly because of the quick-shift af. pentax made a brilliant marketing-through-engineering move by including this feature on all da lenses (unlike canikon, iirc)

by the time i would have figure dit out, that rumoured 17-70 pentax will be out, and i will probably get it without blinking

[MRRiley]

with all due respect , no, you cannot. using your feet changes perspective, zooming (reframing) does not, to mention just one _essential_ point. that's why zooms are bad when you start out with photography: they "teach" you to never think about perspective.

to see what i mean, take your standard 18-55, shoot something (some objects layed out on a table, for instance) at 18, step back to frame the same at 55mm and shoot again (make sure you move on the axis of your lens when you shot at 18mm). it will be obvious

just my 0.02$

I understand that nonok. However, perspective control is rarely if ever considered by the average photographer using a zoom lens. All they know is it makes it easier to get closer to their subject. When I started out with my first SLR in 1975, the last thing I could afford was a zoom lens so I did a whole lot of zooming-with-my-feet. Perspective issues are easily sacrificed to subject size on the film (or sensor).

[MRRiley]

I bought the non-APO Sigma and I am generally happy with it, but I find that I really miss the quick-shift focusing of the DA lenses. I think it is a seriously underestimated feature of these lenses and I would happily pay quite a bit more for that feature. It is easy enough just to switch the AF off, but it's really nice not having to take your hand off the lens. It wasn't until I had to do without it that I realized how much manual focusing I do.

I agree completely code4code5. That quick-shift-focus feature is freaking GREAT. I have a new Tamron 28-75mm f2.8 and while it autofucuses fine it sometimes slightly misses the zone I'd prefer to be in focus. The lack of the quick-shift makes things awkward. In fact I just leave it in manual focus 90% of the time.