I think I am in love... 300-800mm

[Georg Baumann]

http://www.sigma-foto.de/cms/front_content.php?client=1&lang=1&idcat=122&idart=102

Flippin Hell.... 1600mm on my Olympus.... my precsiousssssssssssss <grins>

[Asher Kelman]

http://www.sigma-foto.de/cms/upload/produktbilder/objektive/mtf/mtf_300_800mm.gif a pair of MTF charts. What does that do for your juices?

The weight is 5880 grams, so don't convert that to lb or you'll get a hernia!

Asher

[Steve Saunders]

I'd prefer to see some real-world sample images instead of MTF charts. Sigma lenses (the good ones anyway) tend to have good contrast and nicely saturated colour that tends to look better than MTF charts would suggest.

[Georg Baumann]

a pair of MTF charts.

I have no idea what they are supposed to tell me. Can you briefly explain how to read this? What do the red and green graphs stand for?

[Georg Baumann]

I'd prefer to see some real-world sample images instead of MTF charts. Sigma lenses (the good ones anyway) tend to have good contrast and nicely saturated colour that tends to look better than MTF charts would suggest.

While sigma has a bad reputation on "joe sixpack" lenses, they seem to have a different QM on high end optics, at least this is what people with such quality lenses say.

[Will Thompson]

The weight is 5880 grams, so don't convert that to lb. or you'll get a hernia!

That would be 13 LBS.

And in english:

http://www.bhphotovideo.com/bnh/controller/home?O=photolinks.jsp&A=getpage&Q=LinksFrameset.jsp&url=www.sigmaphoto.com/

[Bart_van_der_Wolf]

I have no idea what they are supposed to tell me. Can you briefly explain how to read this? What do the red and green graphs stand for?

Without more detail one would have to guess, but the two colored line-pairs are usually for wide open and f/8 performance. The charts basically tell me that while center to corner performance drops somewhat in resolution at wider apertures, the lens is a bit low on contrast (due to internal reflections?), and the large number of lens elements/groups needed for a zoom compromise often causes that.

Bart

[Asher Kelman]

Bart, if that's true that it is low in contrast, can that be corrected by a S curve or does it need more than that? What lenses have you found have that issue that is troublesome?

Asher

[John Sheehy]

Without more detail one would have to guess, but the two colored line-pairs are usually for wide open and f/8 performance. The charts basically tell me that while center to corner performance drops somewhat in resolution at wider apertures, the lens is a bit low on contrast (due to internal reflections?), and the large number of lens elements/groups needed for a zoom compromise often causes that.


How do you get contrast from the charts? The charts measure contrast at a line frequency, due to sharpness, not due to global contrast issues.

[John Sheehy]

I have no idea what they are supposed to tell me. Can you briefly explain how to read this? What do the red and green graphs stand for?

Usually the higher set of lines represents f/8, the lower set wide open. The Y axis represents a contrast level for a certain line resolution, the X axis represents mms from the center of the frame, and the solid and dotted lines represent two kinds of resolution; curves centered on the center, and radial lines (I forget which is the dotted). Supposedly, when these lines diverge, bokeh is poor.

These charts would suggest very good performance, but not to the level of Canon's $6000 L telephotos. The lens might outresolve most digital sensors, even perhaps with one 1.4x TC, but with 2x or greater, the camera probably starts to oversample the lens. Of course, starting out with 800mm, there is less need for TCs.

[Georg Baumann]

@Will, thanks, I forgot to post the english link. Here the sigma: http://www.sigma-photo.com/lenses/lenses_all_details.asp?id=3308&navigator=3

And Luminous landscape test: http://www.luminous-landscape.com/reviews/lenses/sigma-300-800.shtml

The image quality appears to be excellent in deed.

@Bart and John, thanks, and btw, what does MTF stand for?

What I really do not understand is the fact that it appears to be not weather proof. Well, I could not find anything mentioning it, so I guess the lense is not sealed, a factor I find disturbing in this price class.

[Marc Hankins]

Yeah, I've used this lens. It's bloody good! the size makes it pretty damned difficult to handle, but with a VERY sturdy tripod you can get amazing pictures with it.

The backpack it comes with is also pretty mahoosive.

p.s. I'll stand by every word said in the Luminous Landscape article.

In regards to the weatherproofing, It has no rubber gaskets on the lens mount, and i might be a little concerned about the drop in filter slot, otherwise the rest is every bit as hardy as an L lens. I'd be fairly happy with it in a light shower, but if its raining more then a little bit i might be slightly concerned about the said spots. I'd have no worries about the zoom/focus rings at all.

Don't quote me on that though ;)

[Georg Baumann]

Hi Marc,

what means you used it? Did you rent it for a shot or do you own this beast?

[Marc Hankins]

Hi Marc,

what means you used it? Did you rent it for a shot or do you own this beast?

I've not used it extensively, It was lurking around the workplace for a few months, but I never really got a chance to use it much on a camera, though I have handled it a fair bit.

The lighting I got to use it in was hardly exceptional when I did get to play, so I can only say so much about the optics of it, though I believe the tests on LL tell you what you need to hear, but I have lugged it around a good few times and I can attest to its build quality.

And I WISH I owned this mother. Wow. If it wasn't for the massive size and lack of IS, this lens would be the ultimate telephoto. Though even if it DID have IS, I'd still suggest slapping it onto of a tripod anyway.