Originally posted by stevebrot Huh? I own two Sigma lenses. My 50/2.8 EX DG Macro is proportioned similarly to and weighs two ounces more than the DFA 50/2.8 Macro. Both have an aperture ring and cover the full 35mm frame. The Sigma is made of metal and the Pentax is made of plastic. The other Sigma is the 17-70/2.8-4 (Contemporary). It is also proportioned similarly to the DA 17-70/4 (slightly smaller) and weighs just a smidgeon less despite being a full stop faster at the wide end.
Specs? Yes, both lenses definitely spec well. Build? Yes, both are very nicely built. Performance? The Sigma macro performs on a par with the DFA 50/2.8 and the Sigma 17-70 is better, much better than the comparable Pentax offering.
So...in what regard are either of these lenses bulky, heavy, and over-spec'ed merely to look good in the press? Or do I own the only two lenses in the Sigma line-up that are exceptions?
Steve
BTW...the 50/2.8 Macro does have a warm color cast, though I would hesitate to label it as yellow or greenish.
Well it depend... Pentax has some lenses that are let say standard lenses and sigma too. That's zooms like 17-70 and things like that. The contemporary line is ok.
You speak of sigma 50mm lenses, let's see the tendancy...
Pentax
FA43 f/1.9 : 2,7cm x 6.3cm, 168g
FA50 f/1.4 : 3.7cm x 6.5cm, 220g
DA50 f/1.8 : 3.8cm x 6.3cm, 122g
DFA50 macro f/2.8 : 7cm x 6.7cm, 265g
DA*55 : 7cm x 6.6cm, 375g
Sigma
50mm f/2.8 macro : 7.1cm x 6.4cm, 315g.
50mm EX f/1.4 : 8.4cm x 6.8cm, 505g
50mm Art f/1.4 : 9.9cm x 8.5cm, 815g
I don't say this is not justified for maximum quality at f/1.4 but this sure doesn't come for free in term of weight & size.
You could repeat that for the 35mm primes or 85mm primes.
On wide angle, pentax offer very small prime lenses (DA15, DA21), while sigma has a big primes at 10, 15, 20, 24mm...
Sigma recently developped a 18-35 f/1.8... Pentax recently developped a 20-40 f/2.8-4. Their size and weight isn't exactly on par.
The 50-135 is lighter too than latest sigma 50-150...
Not to say that sigma is wrong in the absolute, but if one want to argue that sigma have small lenses like pentax this is plain wrong. Sigma has some standard sized lenses as Pentax do... And has huge bulky lenses as opposite of very small & lightweight Pentax lenses.
Choose your preference. It doesn't matter for some standard sized lenses, but it does for others.