Sigma or Nikon?

raphael · Jun 9, 2004

hi there,

I'm wondering which one of these 2 lenses is the best, I hesitate between the Sigma 2.8 /28-70 and the Nikon 3.5 /28-105 D, does anyone know if there is better image quality with the Nikon?
if I win light with the sigma, will It be as sharp as the nikon lens?

thanks a lot for your advice,

Raph.

Rainman · Jun 9, 2004

If I were buying this lens for my every day lens I would save up my pennies until I could afford the Nikon. A half stop is hardly even worth taking into consideration. Not that Sigma isn't a very high quality lens.

raphael · Jun 9, 2004

thanks,

so you mean that the difference between 2.8 and 3.5 is not a good reason to prefer the sigma?

raf.

voodoocat · Jun 9, 2004

I think it is. 1 stop is a big difference. I'm not familiar with the lenses so I can't say which one has better contrast and sharpness. But I wanted to comment on the 1 stop difference.

tr0gd0o0r · Jun 9, 2004

I'd agree that that stop of light can make a big difference, but if there is significant quality differnce, i'd go with the nikon also

Rainman · Jun 9, 2004

I made my statement based on personal perception/preference. I am saying that the difference between 2.8 and 3.5 is about a half stop. 2.8 to 4.0 would be one full stop. I am saying that personally I would not make a lens purchase decision based on 1/2 stop. A better quality lens can be a half stop brighter than a lower quality lens at the same maximum aperture, and there are not many lenses of higher quality than Nikon. Lens aperture (f-stop) numbers are the product of strictly objective calculations, ratios relating the lens opening to the focal length, and are fixed and calculable regardless of lens quality. However, the quality of the optics can allow a better quality lens to pass more light at the same aperture.

So, nominally, the Nikon at 3.5 is a half stop "slower" than the Sigma at 2.8. But in terms of actual light that strikes the film there may be no difference. This may not be the case because Sigma is a very high quality lens. In either case, I personally, do not consider a half stop difference that significant.

ksmattfish · Jun 9, 2004

Besides the 1/2 stop difference, one is a 28-70 and the other is a 28-105. I'll take the 28 to 105 anyday, as this would make it much more useful as a portrait lens for the way I shoot (50mm for full body shots, and 70 to 100+mm for close ups). But cost is a huge consideration; I haven't checked, but I imagine the Sigma is significantly cheaper. You have to weigh all of this together, and decide what is best for you. Both lenses are capable of taking great pics; which one suits you better? Fits into your budget, etc...?

raphael · Jun 9, 2004

thanks for all your replies,

I also must say that I take picture of shows, theatre with ambiant ligh, I need so a luminous lens... But if the Nikon is Sharper, and have less deformation, I'll go for it.

Here is the link to the nikon:
http://www.fnac.com/1183363/rcwwwa/Nikon-AF-28-105-mm-f-3-5-4-5-D.html

and the sigma:
http://www.fnac.com/1184889/rcwwwa/Sigma-28-70-mm-f-2-8-DF-Aspherique-EX-Canon.html

You'll see that the sigma has more stars,

voodoocat · Jun 9, 2004

Rainman said:
the difference between 2.8 and 3.5 is about a half stop.

That's what I meant, you're right.

ksmattfish · Jun 9, 2004

raphael said:
I need so a luminous lens...

For that kind of stuff I'd suggest you look into prime (fixed focal length)lenses. You might be able to get a 50mm f/1.8 and something longer f/2 for what you'd pay for a good zoom. You can get a 50mm f/1.4 for a little more; that's 2 stops faster than the Sigma, and 2.5 to 3.5 stops faster than the Nikon.

Does that Sigma lens stay at f/2.8 at all focal lengths? That's pretty nice if it does. The Nikon goes to f/4.5 when zoomed out. I'd still try to go with something f/2 or better for low light situations.

raphael · Jun 9, 2004

ksmattfish, You're right, but I already have the 50mm 1.4 nikon AI, It's a very good lens!!
I'd like to purchase a zoom, that is the reason why I hesitate between the sigma and the nikon...

Rainman · Jun 9, 2004

voodoocat said:
Rainman said:

the difference between 2.8 and 3.5 is about a half stop.

Click to expand...

That's what I meant, you're right.

I knew that you did, 'cat. :wink:

I was mainly trying to stress to Raphael that I was stating a personal opinion and the basis for that opinion.

nikon90s · Jun 9, 2004

I have the sigma 28-70mm f2.8 is has worked well for me. you can look at my gallery all shots where taking with that lens on a nikon n90s. but keep in mind they where scanned on a cheap scanner.

http://www.pbase.com/jason_lake/nikon_n90s

If you look at the other galleries there some where shot with that lens and others with my sigma 70-200mm f2.8 and a x2

edit post...
here is a shot with my d70 with a backfocus prob and that lens