Best lens for *ist D

I'm in little doubts about which lens to pick up for D... Pentax (Pentax DA 16-45 f/4 ED AL smc) zoom is, as I read, very sharp with good colors, saturation, contrast, etc. from edge to edge... But it has max. aperture of f/4.
On the other hand, the Tamron AF 28-75 F/2,8 LD Asf. XR (IF) Di and Tamron AF SP 17-35mm F/2,8-4,0 LD Asf. Di IF had better max. aperture but I'm not to convinced about those ones.

There's one more possibility with two Sigmas:
Sigma 17-35 F/2,8-4,0 EX Asf. za Pentax
Sigma 24-70 F/2,8 EX DG Asf. za Pentax

They all round 340 GBP - 420 GBP. What do you think? I want to buy Pentax but do you thing I have better option among the 5 of them?

Thank you for youre answers...

Bye - Saso

It all depends what you want to do with the lens. If you expect to spend a lot of time shooting wide open, then the 16-45 might not be a good choice.

But if you really are going to be shooting a lot in low light, you might be better off with a couple of fast prime lenses. In low light, autofocus doesn't work well, so an MF lens is often a better bet. And when used wide-open, M lenses operate in Aperture Priority mode, so the camera will set the correct shutter speed automatically without the green button.

So how about a M 50 f1.4, or a K 50 f1.2, along with an M 85 f2? The other 85s may be outside your budget.

Any 50 f1.4 or f1.7 would be a good thing to have anyway.

G

Hi George!

I have some pentax glass. 50mm A f/1.7, 100mm M macro f/4, 135mm M f/3.5... I have 28mm Vivitar and a few pentax zooms, Zeiss and Tokina too.
I shot photos mostly for the calendars but latterly I was involve in a way in wedding photography. I've made a nice income so I will probably do that too in the future Here is that lens gap I was talking about. I need wide angle for D. But wich one to choose? Pentax will give good photos but the Tamron and Sigma wide aperture... Which one to pick??? What do you think? I would like the opinion about image quality, usability? in a word what would be the best choice?

Cheers - Saso

For me, the answer is obvious - first choice Pentax, closely followed by Tamron, with whatever focal length range you think will be most useful.

Do you really think you need the extra aperture stop?
No zoom lens will deliver it's best results at maximum aperture and while a faster lens will give a brighter viewfinder and allow shooting under lower light conditions, you have to decided just how important that is to your photography, when you take into account the inevitable drop in image quality.

In your place I would go for the 16-45. Unless you know that you have a definite requirement for that extra stop, it is better to go for the lens that will have the highest picture quality, and that is almost certainly the 16-45.

Bear in mind that a digital camera at ISO 800 is much better than ISO800 film, and even 1600 is usable. Do you really need the extra stop?

G

It might be worth waiting to see how the new 12-24mm turns out?

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Best regards, John

I agree with George. I have had faster zoom lenses (though not the ones you mentined), but nothing even came close to the SMC-DA 16-45. Stopped down a bit (f8 - f16) it's amazingly sharp. Just had some 16"x12" prints done at 402ppi - and they're pin sharp

For low light photography I use the SMC-F 50mm/f1.7.

I wouldn't trade the Pentax for even an extra stop. One thing I've learned is that faster lenses are not necessarily better

Matt

Well thank you, guys! You've been very helpfull. There is some powerful argument about 16-45. I thing this lens is a winner. I agree with most of your statements. When the equipment arrive I will let you know. I will do some test photos and report what you all already know that the lens is great!

Have a nice day, regards - Saso

Is this the case with the 50/1.7 and 50/1.4 though? I've read some test results which show that the 1.4 is slightly sharper than the 1.7 (not that this difference is significant enough to have an effect on image sharpness though, I'll bet).

One things for sure, I can't wait to fix my 50/1.4 A on to a istDL when I get one! I hope to get some great portrait images with this combo.

Well, i can't second that. The 50/1.7 variants do have slightly (very slightly) better sharpness wide open compared to the various 50/1.4. Usually a faster lens will be weaker then a slower one wide open and this counts for any Fast Fifty Pentax has ever made with the exception of the weaker M and A 50/2.0.

If you are interested in wide open performance the poll is usually:
f1.7 > f1.4 > f2.0 > F1.2
(Wide Open optical performance not counting macros and older takumars).
When stopped down the optical quality is very comparable or even indistinguishable from f2.0 and up. In terms of sharpness i doubt that you can find a difference at f2.8 between 1.4 and 1.7.

Besides: If you want a tack sharp 50 look at the slower macros like the 50/2.8.

my two cents

Hi,
The 1.7s do tend be be sharper and even Pentax say that the 1.4s are not the best for macro work because of a weaker flat field performance. However, sharpness is not everything and how often do you do critical work wide open. The 1.4s and indeed the 1.2 give a much better 3D modeling effect and for general photography can give more pleasing results. As always it is a case of matching the lens to the job.

Kim

My 50/1.4 certainly provides a noticeable 3-dimensionality to images in the right lighting conditions; more so than any other lens I've used. I haven't noticed edge softness at wider apertures, but 2.8 is the widest I've gone so far.

I just love this lens, perhaps even more than my 24/2.8, which is great for landscapes but not as versatile as my 50mm (e.g the wide lens gives stronger converging verticals and unflattering distortion of facial dimensions in people pics). Optically, they both make me smile time and time again

To manufacture a 50mm f1.4 is more challenging than a F1.7, and the wider aperture may well have a downside in terms of some qualities.

As regards the pentax lenses, it's not so much a matter of sharpness, which is fine, but more that the f1.4 has different qualities. It has higher contrast and lower fine resolution, which reflects the probable final use for reportage and low light situations where the high contrast may be an advantage.

The f1.4 will also not have as flat a field and won't be as forgiving when used with extension tubes or converters. But it's not designed for these things, so the buyer can make a decision as to which properties will be the most important, and buy the lens to suit.

The trouble is that this sort of information is not supplied properly by any of the manufacturers, which is a pity because I for one would have saved a lot of expense over the years if it had!

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Best regards, John

To sum up, all these lenses have their own particular strengths, which will make each of them the right choice in a specific situation.

It therefore follows that you need one of each.

G

I keep trying to tell my Wife that but for some reason she doesn't believe me and keeps muttering "Bank Balance". There is no justice in the world!

Kim