[anyscreenamewilldo]

hi dear Pz'ers,



i've read the review here (on a D200) of the sigma 100-300 f4



question is - is anyone familiar enough with this lens to say it might look nice and sharp enough if i buy it for a 24mp full frame -





ta,

any

[allanmb]

[quote name='anyscreenamewilldo' timestamp='1285315858' post='3193']

hi dear Pz'ers,



i've read the review here (on a D200) and looked at a copy of this lens on a 7D - the review is very good - my check on the 7D may indicate it is ok (i'm not familiar with canon set up, so some of the settings were wrong and the slightly soft pictures maybe came from a too slow shutter speed, but apart from that the pictures were nice - ahem, don't take this too seriously dear canon but i couldn't do much post = you're a tad different for me at the moment . . . or, what you see is what you get!) -



question is - is anyone familiar enough with this lens to say it might look nice and sharp enough to do post on if i buy it for a 24mp a900 - or it might not make the grade on such a sensor?? - my grade (you can look see here on pz gallery)



ta - if i don't hear back, maybe i'll give b&h's returns policy a try . . . or maybe not . . .



keith (any....)

[/quote]



What a difficult post to read!



Anyway, if I understand you correctly you are concerned with the Sigma 100-300 f/4 not being sharp enough for a full frame 24MP sensor? I would say that the lens is definitely sharp enough for such a sensor. I use it on my 50D with great results (the 50D has a larger pixel density -15MP but 1.6x sensor).



I absolutely love my 100-300. It has great IQ, takes a 1.4x and 2x TC very well. The f/4 provides decent shutter speed and good background seperation. I would definitely recommend it to anyone!



Allan

[Brightcolours]

[quote name='anyscreenamewilldo' timestamp='1285315858' post='3193']

hi dear Pz'ers,



i've read the review here (on a D200) and looked at a copy of this lens on a 7D - the review is very good - my check on the 7D may indicate it is ok (i'm not familiar with canon set up, so some of the settings were wrong and the slightly soft pictures maybe came from a too slow shutter speed, but apart from that the pictures were nice - ahem, don't take this too seriously dear canon but i couldn't do much post = you're a tad different for me at the moment . . . or, what you see is what you get!) -



question is - is anyone familiar enough with this lens to say it might look nice and sharp enough to do post on if i buy it for a 24mp a900 - or it might not make the grade on such a sensor?? - my grade (you can look see here on pz gallery)



ta - if i don't hear back, maybe i'll give b&h's returns policy a try . . . or maybe not . . .



keith (any....)

[/quote]

The Sigma 100-300mm f4 is quite a special lens. You will not find a sharper zoom lens in these ranges. It will certainly "make the grade" on your 24mp A900... after all, the A900 does not really have a higher pixel density than a Nikon D200 10mp APS-C camera.



Why would you return it if you "do not hear back"?

[Guest]

It's difficult to tell how it will behave on a full frame sensor - it might have terrible borders

Anyway, considering all that praise given to this lens, it is more than likely that I had a lemon: I hated the image quality of my Sigma 100-300 - sharpness *way* below my old Nikon 80-200 f2.8, absolutely horrible bokeh, frequent focussing errors, etc. The only thing I liked was the build quality - real metal tank :-)

[anyscreenamewilldo]

this is excellent news allan and Bright, thanks . . . it looks therefore to be the one missing link in my 'most useful' lenses line up





thanks,

any

[anyscreenamewilldo]

[quote name='Lomskij' timestamp='1285333793' post='3201']

It's difficult to tell how it will behave on a full frame sensor - it might have terrible borders

Anyway, considering all that praise given to this lens, it is more than likely that I had a lemon: . . . sharpness *way* below my old Nikon 80-200 f2.8, absolutely horrible bokeh, frequent focussing errors, etc. The only thing I liked was the build quality - real metal tank :-)

[/quote]

whoops - i've just seen this and you've dropped a spanner in the works Lomskij - but another point of view is useful - i liked the bokeh i saw, i'll check again the sharpness -



thanks Lomskij

[Brightcolours]

[quote name='anyscreenamewilldo' timestamp='1285337294' post='3203']

whoops - i've just seen this and you've dropped a spanner in the works Lomskij - my main concern is about sharpness, the bokeh on the 7D looked nice (or has my perception been spoiled by my reflex lens?) -



ok, it's back to the shop to recheck the canon version of this lens - i've been studying up on setting the canon the way i want it - does anyone else think the canon menu a tad confusing? - but i suppose it's what is familiar that makes sense . . . maybe a bit like my posts? -



thanks Lomskij

[/quote]

Don't let one bad sample make you have a wrong perception of a lens.



Now, there is something I do not understand. You talk about returning a lens. You talk about selling it to nigerians (what would the postage be??).

You talk about a D200 test, AND you talk about trying it on an EOS 7D.



All that seems so jumbled indeed.



Is it correct to presume you do not have the lens for your A900? And that you maybe ordered it to fill a hole in your lens collection for your A900? And that you tried it on a 7D in some store, and are not sure about the sharpness?



You are aware that digital cameras have an AA-filter, and that the AA-filter is there to prevent false detail and odd colour patterns and aliasing? Not all cameras have the same strength of AA-filter. A stronger A-filter is not bad, as usually you do not lose more real detail.. AA-filter "softness" can be sharpened up really well.



I am assuming that you pixel peeped, and that you noticed a difference in per pixel apparent sharpness between what you are used to from your camera, and the few images you took with the 7D + 100-300 combination.



We can not make any sensible comment on that, since we do not have 100% crops to see what you are/were seeing. We can not see if it is normal AA-filter softness, we can not compare it against another lens on that 7D either, we can not see if the lens is a poor sample or not. Basically, we can't say much except that the Sigma 100-300mm f4 is a lens that has been a top lens for 10 years or more, a really good design.



It should do really well on a full frame camera (unless it is a sample with a problem, obviously), so also on your A900.



About the D200 and A900 pixel density...



The A900 has 6048 pixels horizontally, the D200 has 3872 pixels horizontally.

6048 / 35.9mm = 168.5 pixels per mm.

3872 / 23.6mm = 164 pixels per mm.



As you can see, they are very, very close.



Your D2x has a higher pixel density than your A900:

4288 / 23.7 = 181 pixels per mm.



The EOS 7D: 5184 / 22.3mm = 232.5 pixels per mm.

[allanmb]

Dont worry about sharpness. Here are a couple of shots from mine:



300mm f/4:





600mm f/10 100% crop





Allan

[Brightcolours]

Well... that frog certainly is worrying about sharpness! <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/unsure.gif' class='bbc_emoticon' alt='' />

[anyscreenamewilldo]

[quote name='Brightcolours' timestamp='1285343886' post='3206']

. . . . Basically, we can't say much except that the Sigma 100-300mm f4 is a lens that has been a top lens for 10 years or more, a really good design. . . . [/quote]



ta Bright



and on a separate post re. Allan's added pix - lovely pictures, thank you Allan - i'll have one please . . . and the lens too, ta