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Trying out the Sony A900 and Zeiss 24-70

Arne Hvaring

Well-known member
Hi Jono, thank you for sharing your impressions of the a900, the info re the weak AA filter is interesting and would indicate excellent resolving power+more realistic looking images out of the box (so to speak). I just read Chasseur d'Images quite favorable test of the Sony. They seem to indicate that high ISO noise isn't nearly as bad as some early posted images would lead us to believe.
Personally, the lack of live-view is a deal breaker, so I just hope Nikon has the good sense to follow Sony when it comes to AA filtering,or ideally drop the *#¤ thing :), when they present their high res DSLR.
 

jonoslack

Active member
Hi Jono, thank you for sharing your impressions of the a900, the info re the weak AA filter is interesting and would indicate excellent resolving power+more realistic looking images out of the box (so to speak). I just read Chasseur d'Images quite favorable test of the Sony. They seem to indicate that high ISO noise isn't nearly as bad as some early posted images would lead us to believe.
Personally, the lack of live-view is a deal breaker, so I just hope Nikon has the good sense to follow Sony when it comes to AA filtering,or ideally drop the *#¤ thing :), when they present their high res DSLR.
HI Arne
Certainly the images seem fine 'out of the box'. I've now done some A2+ prints which you really can eyeball (even my 20 year old can't see any problems).

I hear you about the live view, although they do have this 'preview' thing, which is okay if you are on a tripod.

As for the noise - well, of course the trouble is that the first thing you do is look at it at 100% - which is fine, but it's half the area of the frame with a D700, I suppose one should really compare at 50% on the Sony and 100 on the Nikon. Whatever - I've done some ISO 800 and 1600 shots tonight, and they seem to be pretty good. Although not in the same league of course. I'm not sure quite why it should be the case, but it seems to me that good low noise has a pretty direct correlation with strong AA filters: I suspect you can't get the best of both worlds at the moment (and Nikon certainly seem to be in favour of stronger filters at the right now). To be honest, this was one of the motivations of the change - it's all very well waiting until next summer for the Nikon - but if it's in a D3 sized body, has a heavy AA filter, and costs £4000 . . . .
 

Arne Hvaring

Well-known member
HI Arne
Certainly the images seem fine 'out of the box'. I've now done some A2+ prints which you really can eyeball (even my 20 year old can't see any problems).

I hear you about the live view, although they do have this 'preview' thing, which is okay if you are on a tripod.

As for the noise - well, of course the trouble is that the first thing you do is look at it at 100% - which is fine, but it's half the area of the frame with a D700, I suppose one should really compare at 50% on the Sony and 100 on the Nikon. Whatever - I've done some ISO 800 and 1600 shots tonight, and they seem to be pretty good. Although not in the same league of course. I'm not sure quite why it should be the case, but it seems to me that good low noise has a pretty direct correlation with strong AA filters: I suspect you can't get the best of both worlds at the moment (and Nikon certainly seem to be in favour of stronger filters at the right now). To be honest, this was one of the motivations of the change - it's all very well waiting until next summer for the Nikon - but if it's in a D3 sized body, has a heavy AA filter, and costs £4000 . . . .
H Jono,
quite agree on the noise issue. IMO the most relevant way to compare the *real* noise level of two (or more) cameras is to make identical prints in one's usual size and carefully inspect them. Since a paper print is the final destination of my photography (and not a 100% crop on a LCD screen :p) that's what I'll be looking at.

Well, if Nikon makes the mistake of bringing out another overpriced, overfiltered heavy brick of a camera, I'm definitely not buying it. I'll do just fine with the 1DsIII and Leica and Zeiss (and a few Canon) lenses. Might even consider exchanging the 1DsIII with the new 5D-II. Or buy it as a back-up/video camera for fun.
 
A

asabet

Guest
... I suppose one should really compare at 50% on the Sony and 100 on the Nikon. Whatever...
About 70.4% for the Sony and 100 for the Nikon ought to do the trick based on the relative linear dimensions at maximum native file sizes.

I'm not sure quite why it should be the case, but it seems to me that good low noise has a pretty direct correlation with strong AA filters: I suspect you can't get the best of both worlds at the moment (and Nikon certainly seem to be in favour of stronger filters at the right now)...
A stronger AA filter should decrease detail without affecting noise to as great an extent (some components of noise, eg read noise, aren't affected at all by the AA filter), whereas sharpening to get more detail in the presence of a strong AA filter will make noise more evident. Thus a strong AA filter has a net effect of increasing apparent noise for a given level of detail. I've always thought that Olympus is exacerbating their "noise issue" by using a strong AA filter.

I think that the correlation you're finding is due to the fact that 1) large pixel cameras are more susceptible to aliasing and thus require stronger AA filters, and 2) large pixels currently have lower read noise than aggregations of small pixels of equal area (reference). Thus the cameras with the strongest AA filters happen to have the best low light high ISO performance, but there's no direct cause and effect there.
 
G

GLJ

Guest
And thanks , Guy, for the welcome to the forum. Looks like the place where sensible folk hang out (which kind of disqualifies Jono and me :ROTFL:)
And you think you two are bad? Well, look who else has just joined! There goes the neighborhood .....

G.

PS - Jono .... don't blame me for THIS purchase. The 'Autumn approaching and you need 25MP to take pictures of coloured leaves' comment isn't a valid reason ok!

PS - Q, I need some advice. I've just bought a book and there's a picture of some bloke waving his wad at me on the front cover in a crazed yet menacing manner. I'm suffering mental trauma each time I look at it. Can I sue the author ??
 

Quentin_Bargate

Well-known member
I recall Kodak justified the absence on an AA filter on the Kodak 14n on the basis the resolution was high enough not to need it. at 14mp they were probably wrong in that case at least. I certainly spent many hours removing colour aliasing from Kodak files.

The irony is AA filters are quite expensive. Kodak brought the cost of their cameras down by making an AA filter optional. My Mamiya ZD has a IR filter, but no AA filter - the AA filter is a near $1k optional extra. The ZD is amazingly sharp before diffraction kick in below around F/8. Colour aliasing is an occasional issue, but one I can work around.

My interest in the A900 stems from the fact I shoot work for stock. Now, typically, RM stock photo libraries want files of at least 50mb (at 8bit). The ZD produces 62mb files at 8 bit, so I'm well over the threshold, and they are razor sharp, but its too big a camera to lug around everywhere and its rubbish above 100 ISO. Essentially, the ZD is a studio and tripod camera, although I also use it hand held. With the D700, I need to rezz the files up, which is no great problem as the data are high quality. But a 20mp+ smaller format would mean no interpolation necessary, which is tempting, particularly if Nikon mess about with a monster body for the "FX" format high rezz camera.

Quentin
 

Quentin_Bargate

Well-known member
And you think you two are bad? Well, look who else has just joined! There goes the neighborhood .....

G.

PS - Jono .... don't blame me for THIS purchase. The 'Autumn approaching and you need 25MP to take pictures of coloured leaves' comment isn't a valid reason ok!

PS - Q, I need some advice. I've just bought a book and there's a picture of some bloke waving his wad at me on the front cover in a crazed yet menacing manner. I'm suffering mental trauma each time I look at it. Can I sue the author ??
Ha, that you Gareth?! Sue the author of a masterwork? I think not. I'd sue the guy who allowed said author/photographer to take the pic in his studio. I have his name and address if you need to pass it to your legal representatives :ROTFL:

Standards certainly are slipping..:LOL:

Quentin
 
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