[Moe49]

I am looking at buying either a "Sigma 24-70mm f/2.8 EX DG [non-HSM with aperture ring]" or a "Pentax FA* 28-70mm f/2.8" to replace my DA*16-50mm. I like the 16-50 a great deal, but it lacks an aperture ring, and is a 'cropped sensor' lens, so it's incompatible with my film cameras.

There is a huge price difference between the Sigma and the FA* [~3x], but I would expect a superior lens to be exponentially more expensive.

My questions for those with some experience with these lenses:

"Is the FA* superior? Say 25% better, than the Sigma?"
"Or are images captured with both lenses indistinguishable?"
"Which lens would you advise I persue?"

Thanks for your time & advice,

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Last edited by Moe49; 04-22-2011 at 03:07 PM.

[Doanh]

How about Tamron 28-75? It's cheaper than the two you are considering. In fact it is the cheapest with rave review.

[axl]

The Sigma seems a good lens but it never amassed the following as big as the Tamron 28-75. Probably because of the size. One issue that would pop up again and again is the flare resistance with the Sigma but then I'm not too sure whether Tamron is any better. And then of course the zooming where the lens is physically longest @24mm which is tad odd and might cause problems with built in flash. Other thing to keep in mind is resale value. I don't see the Sigma going up in any way, the FA* will definitelly not loose value if you keep it in good shape!

My 2p

[borno]

+1 for the Tamron, I loved mine when I had it. It was the one good lens I held onto before selling my last Pentax digital body.

[Winder]

Tamron is the best deal for the quality. The Pentax is a better lens, but the difference is not worth the price. The Sigma is weak compared to the Tamron or the Pentax.

If you have to have an aperture ring then go with the Pentax.

[mlatour]

My opinion on the Sigma 24-70mm f2.8 EX DG MACRO (non-HSM):

If you are going to use it to replace a 16-50mm, you are very likely going to miss those precious 8mm at the wide end with the Sigma 24-70mm. I had one for a few months last summer/fall and it simply wasn't wide enough when familiar to using my Sigma 18-50mm f2.8. EX DC MACRO. Those extra 20mm at the long end didn't make much of a difference.

As mentionned in other posts, it is quite a large lens, takes expensive 82mm filters,
tends to flare a lot, has a tiny zoom ring which can make difficult to operate quickly during 'action' type photography.

On the other hand mine did focus quicky and accurately, and apart from the flare issue
in certain situations, image quality was pretty good.

I've never tried the Tamron 28-75mm f2.8, but if you have another lens to cover wider than 28mm, it might be a better option than the Sigma 24-70mm.

edit: your post mentions you plan on using it on a film SLR, my comments were experiences using it on a crop sensor, so 24mm may be plenty wide for you.

Just my 0.02$ ...

Michel

[Kaufeetime]

This site may help resolve the dilemma or start an argument.
Third Party Lenses Resource Megasite Home Page

[Moe49]

Thanks for taking the time to respond with your opinions.

Over the past few days I've compared specs, reviews and sample shots [lens clubs], for the following three lenses:

Pentax FA*28-70 f/2.8
Sigma 24-70mm f/2.8 EX DG [with aperture ring]
Tamron 28-75 f/2.8 [with aperture ring]

Despite it's premium cost, I think the Pentax is the right lens for me. It has the highest user review average score[9.29]. The only negatives reported: weight and rotating front element. I already have a FA*200mm, and it impresses me 'mightily'. I'm sure a FA*28-70 will do likewise.

The Tamron had the 2nd highest user review scores[8.76], and IMHO the best performance/cost ratio. Negatives reported: QC, FF/BF issues, 'plasticky' feel. My only encounter with a Tamron lens is one I owned for a few months. It just did not impress me with it's handling, IQ and 'plasticky' feel. So, I'm a bit cool towards Tamrons [maybe unfairly so].

The Sigma ranked lowest of the three at [8.55], a respectable score nonetheless. Negatives reported: flaring, QC, filter size and weight.

This all started because I am looking "to replace my DA*16-50mm. I like the 16-50 a great deal, but it lacks an aperture ring, and is a 'cropped sensor' lens, so it's incompatible with my Pentax film cameras." Will I miss the 16-27mm range on my K7d? Maybe, but with the DA*16-50, below 20mm I get some barrel distorion, so I avoid that range anyway.

[edit 5/5/11] purchase completed for a FA* 28-70 f/2.8, now awaiting shipment [Thanks Steve in Australia !]

[edit 12/31/11] I am very very happy with the FA* 28-70 f/2.8 !! The colors ! The IQ ! The extra cost is long forgotten
I have been so impressed with this lens that I have since purchased it's bigger brother, the FA* 80-200mm.

[Pentaxor]

Thanks for taking the time to respond with your opinions.

Over the past few days I've compared specs and reviews for the following three lenses:

Pentax FA*28-70 f/2.8
Sigma 24-70mm f/2.8 EX DG [with aperture ring]
Tamron 28-75 f/2.8 [with aperture ring]

Despite it's premium cost, I think the Pentax is still the right lens for me. It has the highest user review average score[9.29]. The only negatives reported: weight and rotating front element. I already own a FA*200mm, and it impresses me 'mightly'. I'm sure a FA*28-70 will do likewise.

The Tamron had the 2nd highest user review scores[8.76], but has the best performance/cost ratio. Negatives reported: QC, FF/BF issues, 'plasticky' feel. My only encounter with a Tamron I owned for a few months, just did not impress me with it's handling, IQ and 'plasticky' feel. So, I'm a bit cool towards Tamrons [maybe unfairly so].

The Sigma ranked lowest at [8.55]. Negatives reported: flaring, QC, filter size and weight.

This all started because I am looking "to replace my DA*16-50mm. I like the 16-50 a great deal, but it lacks an aperture ring, and is a 'cropped sensor' lens, so it's incompatible with my film cameras." Will I miss the 16-27mm range on my K7d? Maybe, but with the DA*16-50, below 20mm I get some barrel distorion, so I avoid that range anyway.

mind you that user ratings are mostly subjective. that means the small scoring differences are negligible and shouldn't be used as a barometer in telling that one lens is better than the other. you should not what you are expecting to get from the lens in terms of performance that you are looking for.

[NeverSatisfied]

Will I miss the 16-27mm range on my K7d? Maybe, but with the DA*16-50, below 20mm I get some barrel distorion, so I avoid that range anyway.

Hi Moe,
Regarding your barrel distortion concerns, there are now lens profiles available (in LightRoom for example), that correct distortion and chromatic aberration. I've used the DA*16-50 profile and it works quite well. Something to consider.

[Lowell Goudge]

the sigma 24-70 was one of the lenses I considered when looking for a lens between my 10-20 and my 70-200 (both sigmas)

Ultimately I went with a tamron 28-75 which is a good lens (ranked sharpest in class when I bought it)

there are other deciding factors.

the 24-70 was huge and took unusual 82mm filters that had nothing standard with what I had. the 24-60 also got consideration as it used 77 mm filters, but, ultimately the small size and IQ of the tammy won out.

Note I already had 2 different graduated ND filters and a polarizer for the 67mm tammy accessory ring, which I share between the tammy and my FA-J 18-35.

Filter cost is one consideration since each filter in this size is easily $60+

The one thing i do find with the Tammy is that the 20-28 gap can be an issue at times. I still carry my FA-J 18-35 to fill it, and although not as fast, it is a competant lens.

As the OP has mentioned, except for my 10-20, all my other lenses are full frame, and I still shoot with my PZ-1 from time to time, although lack of an aperture ring is not an issue with the PZ-1 it might be for people using a K1000

[Moe49]

Wish I had known about this lens earlier:

Tokina AT-X Pro 28-70mm f2.6-2.8 Lens Reviews - Pentax Third-Party Lens Review Database

Oh well, timing is everything. I will be giving the Tokina AT-X Pro 80-200mm f2.8 very serious consideration as I look for a DA* 50-135 replacement.

[Moe49]

I am a very very happy new owner of a FA* 28-70 f/2.8 . After a few outings with this lens, the extra cost is long forgotten
I am so impressed with the lens that I have since purchased it's bigger brother, the FA* 80-200mm

Here are some shots from our last Mountain Biking vacation in October, taken at Baldwin Beach, South Lake Tahoe.

edit 1/30/2012:
Quote from veteran member below: "I try to find were was the focus on these photo, something is wrong for sure"

Because of the focus comment made, I sent the lens to our favorite Pentax repairman. My FA*28-70mm lens just came back from Pentax_Repairs, i.e. Eric Hendrickson in Tennesse, with a clean bill of health. From Eric's repair invoice: "FA 2.8 28-70mm Check focus. (The focus on this lens is perfect). Clean optics."

The FA*28-70 passed it's focus accuracy tests with a perfect score, therefore it can not be blamed for what others may see wrong in my photos. Blame the K7 auto-focus system, or my aging eyesight, or the resize/compress requirement to post here at PF.

These pictures were taken handheld from a sandy beach. We were on a Mountain Bike ride and I did not have a tripod and remote trigger with me. The un-compressed, un-resized images look great on my Samsung monitor

end edit:

[bobmaxja]

I try to find were was the focus on these photo, something is wrong for sure