[Tommot1965]

Guys


Im in a quandary with my LBA { thats if I keep my K5..dont ask }

I want a Medium Tele zoom... I've a sigma HSM II 70-200 but I find it soft at 200..even stopped down to 5.6..for me that is

ive the new sigma 17-50..and boy is that sucker sharp..everything ive read about the new sigma 70-200 OS HSM..says that it too is sharp..not the same league at the 17-50..but pretty good for a 70-200...it scores better than the Tammy 70-200 at DPR...

But heres the BUT

...how much better is the Pentax 60-250 if at all...is the F4 too much of a trade for the increase in sharpness? I wish DPR had a review of the pentax , then I could compare the two...but they don't..photozone do..and MTF scores very well for the pentax....but I dont think I can compare that score with the DPR review of the Sigma 70-200 OS

I want a sharp lens.....advise me please ..

---

Last edited by Tommot1965; 12-26-2010 at 10:55 AM.

[dgaies]

Well, assuming you keep the K-5, the 60-250 is an excellent choice. I've used the Sigma 70-200 HSM and also wasn't particularly impressed with the sharpness at 200, nor the sharpness across the range wide open at f/2.8 for that matter. I feel the 60-250 is quite sharp from wide open (f/4) on up and the extra range on both the wide and long end is nice to have. FWIW, it's about the same size and weight as the 70-200/2.8 options. I also currently own a Tamron 70-200/2.8 which I also find to be very sharp across the range, wide open as well. I'm trying to decide which to keep (keeping both seems a bit excessive). For me it comes down to the better range and WR (of the 60-250) vs the faster aperture and a lower cost (of the Tamron 70-200). Neither are speed demons when it comes to AF, and from all accounts the Sigma HSM lenses are quite a bit faster.

I can't offer any specific advice on the new Sigma 70-200 OS HSM as I've never used one, but as you said it's suppose to be excellent, albeit a bit expensive.

[Tommot1965]

thanks for the reply Dgaies
good to hear from someone that owns both the 60-250 and the Tammy 70-200

how do you find the VF brightness of the 60-250 v the Tammy 70-200..

ive used the tammy 70-200 and found the VF to be very bright at 2.8..very nice actually , the sigma 70-200 HSM......IMO is not as bright ...

I dont want a dark VF like the 16-45 gives you..the new 17-50 Sigma I've just bought gives a very bright VF and fairly dumps on the 16-45...


be nice if someone had some sample pics of the newer sigma 70-200..


the pentax is a tad cheaper than the newer Sigma at the MO

[dgaies]

I can't say that I've ever noticed or felt that the 60-250 VF was too dark. Part of that may be because I tend to use the 60-250 outdoors in decent light, where as other f/4 lenses like the 16-45 would be more likely to used indoors in lower light. I used to use the 60-250 on my K-x, whose VF is darker to begin with, but even then I never found it to be a major problem.

I'll throw the two lenses on my K-5 this afternoon and see how much of a difference I can notice when I'm looking for it.

Just out of curisoity, is there a reason you're not considering the Tamron 70-200 as well?

[Tommot1965]

i didn't get the Tammy...as I was buying the lens for basketball pictures...and wanted the faster HSM, rather than screw drive...plus i liked the FTM focus ring of the sigma, rather than the clutch of the tammy.

plus I got the sigma used, at a very decent price...and Id have to say that's what ultimately what pushed me into it .

hows the SDM on the 60-250..is it the same speed at the tammy screwdrive ?

[dgaies]

i didn't get the Tammy...as I was buying the lens for basketball pictures...and wanted the faster HSM, rather than screw drive...plus i liked the FTM focus ring of the sigma, rather than the clutch of the tammy.

plus I got the sigma used, at a very decent price...and Id have to say that's what ultimately what pushed me into it .

hows the SDM on the 60-250..is it the same speed at the tammy screwdrive ?

Makes sense. The quick-shift/FTM of the DA*/Sigma is a nice touch over the clunky push/pull clutch (+body switch) of the Tamron. I never got to experience the speed of the HSM of the Sigma as the used copy I bought had a faulty HSM motor. I returned it but ended up finding a decent deal on the 60-250 and bought that instead.

The speed of the SDM 60-250 and the Tamron 70-200 is comparable. I just mounted each lens timed how long it took to lock on to two different objects back and forth 20 times. One object was about 8-10 meters away and the other about 2 meters away. It took the Tamron 24 seconds and the Pentax about 27 seconds. Not night and day different, but I would certainly say that without looking at the clock after I was done, I knew that the Tamron felt quicker to focus and lock than the Pentax. Now, keep in mind, this was in relatively low light (4-5 EV) where the larger f/2.8 aperture of the Tamron probably gives the AF system an advantage. In better outdoor light I think the two lenses would closer in AF speed. Bottom line, I would say the AF of the two lenses is similar, which is not terrible, but not blazing fast either. They both beat the DA*50-135 for what that's worth

EDIT: just wanted to ad that when the Tamron misses focus and has to cycle through the whole focal range, it feels like it takes forever. In cases where you have to constantly go through the whole focal range, the 60-250 becomes the relatively faster lens because it seems to have a short throw and cycles a bit faster, Again, at the end of the day the speed of the two lenses is probably a wash overall and which one is faster depends on the light level and how often you're going from close focus targets to far focus targets.

[Tommot1965]

thanks for doing that Test Dgais...your a trooper mate

Id love test these lens myself...but i cant find a shop here that has them...and i dont want to order one before I test ...

any Perth people out there willing to let me test their lens :}

---

Last edited by Tommot1965; 12-26-2010 at 08:14 PM.

[dgaies]

thanks for doing that Test Dgais...your a trooper mate

Id love test these lens myself...but i cant find a shop here that has them...and i dont want to order one before I test ...

any Perth people out there willing to let me test their lens :}

Where did the rest of your post go? I was just about to reply when it disappeared

[Tommot1965]

Where did the rest of your post go? I was just about to reply when it disappeared

i deleted it,, as after I reread it..it seemed to waffle on a bit..sorry


I wont repeat it...but was I on the wrong track do you think?


My head aches


I need to go and take some pictures....all these reviews are killing me !!

[Tommot1965]

here it is....I still had it on another page..


"Thanks for doing that test Dgais...your a real sport.. rep added


so in as far as sharpness is concerned you say that both the Tammy and the Pentax are equal to your eye?


heres another twister for you...MTF resolution findings from one website to another.

Ive been told, and makes sense not to compare MTF findings from Photozone and DPR, also across different platforms, comparison shouldn't be made with equal lens,

but heres the sticking point..i cant find a site that has done MTF scores for all the lens that Im comparing.....so my work around..as such is to find a common denominator between these sites.......One lens that both sites have compared and use that as a bench mark for the other lens that have been tested in this case the
Canon EF 70-200mm f/2.8 USM L IS.....{are you still with me }


the reason is ive found inconsistencies between both these sites. and my conclusion is that photozone's MTF score is always above the DPR score..

for example this lens at 135mm/2.8 scores 1821 centre 1668 border at photozone, where as DPR rate it lower ..centre 1050 border 850..they don't give exact MTF readings with their widget..but id say im close in my approximation ...

so photozone has a review for the pentax 60-250
DPR has a review for the Sigma 70-200 OS

ill use the 135mm@f4 as a example for each lens....pentax at photozone scores C 2154 B 1924

the sigma 70-200 OS at DPR 135mm@ F4 C 1500 B 900

if you have stopped reading..i wouldnt balme you..im a second away from deleting this post...hang in there!!

so should I add the inconsistencies values to the dpr review to bring them in line with the P/Z review using the canon lens as the common denominator

this would bring the sigma 70-200 OS to around Centre 2400 and border 1600 MTF

as I believe the difference between sites is about 800 MTF
."

[Frogfish]

where as DPR rate it lower ..centre 1050 border 850..

Those surely can not be correct - way way too low for any lense never mind a Canon.

[dgaies]

Those surely can not be correct - way way too low for any lense never mind a Canon.

I think I see where the numbers came from.

The low numbers the OP quoted were from the original 70-200/2.8 on a 40D. The numbers for the new Sigma were tested on a 7D. As far as I know, you can't compare the two numbers as they were taken on different bodies.

FWIW, the Canon and Sigma 70-200 seems to be on part in terms of resolution. Hard to saw exactly where the 60-250 falls, although I imagine it's not too far off even if it is a little lower.

[Tommot1965]

I knew Id have it wrong...cheers for putting me straight

now i need to find some examples of these lens......Id like the 2.8....

how does the extra 50mm at the long end feel....is it worth the lack of a extra stop over a 2.8 lens l ?

those figures for the canon lens at PZ were from a canon 350D..done in 2005

the Pentax was on a K10..done this year

[dgaies]

I knew Id have it wrong...cheers for putting me straight

now i need to find some examples of these lens......Id like the 2.8....

how does the extra 50mm at the long end feel....is it worth the lack of a extra stop over a 2.8 lens l ?

those figures for the canon lens at PZ were from a canon 350D..done in 2005

the Pentax was on a K10..done this year

The extra 50mm is nice to have, although don't overlook the extra 10mm at the wide end as well. The question of whether or not it's work giving up the extra stop over the f/2.8 lens is a subjective one. Perhaps being able to push the K-5 an extra stop or two might make a longer f/4 lens like the 60-250 more viable in situations where the f/2.8 zoom would have been more important with a K-7 body. There is no easy answer, as evident by the fact that I still can't answer that question for myself despite owning both lenses at the moment (well, not the Sigma, but the Tamron 70-200/2.8).

What are prices like for each lens on your side of the world? From what I recall the new Sigma is very expensive, over 30% more than the DA*60-250 (about $1600 vs $1200). You can probably even get a used DA*60-250 for under $1000 if you were so inclined where as I doubt there are any used version of the newer Sigma floating around yet.

[JHD]

If you buy an SDM lens, don't buy it used. Buy it brand new and get the longest extended warranty available, preferably one that can be renewed... to avaid being screwed!