It is called focus breathing.
Read this: http://www.flickr.com/groups/356195@...7626009166844/
Last edited by daredevil123; 9th September 2011 at 09:33 PM.
All DSLR focal lengths are based on Full frame specifications, whether or not it's DX or FX in Nikon context.
Therefore, all DX lenses like for example 55-200mm is actually 82.5 to 300mm (FOV equivalent on FF) on all DX cameras. You still need to mulitply the 1.5 crop factor even though it's a DX lens.
FX lenses are all usuable on DX cameras (1.5 crop factor need to be applied just as well) - but keep in mind that the D lenses cannot AF on lower end DX bodies due to the lack of motor screw to drive the AF on the lens. Some even older lenses like Ai/AiS can't be metered on lower end DX bodies - but can still be fitted on the bodies and you have to guess the exposure yourself.
Nikon's 70-300 VR while due to really bad CA results, is very sharp nevertheless. Recently bought it for my kid's D5000 and it works really dandy. The results are more impressive than I thought initially.
Tamron's latest 70-300, while better than Nikon's CA control has a different way of handling VR... Some may get used to it, some may not - it's based on personal preferences.
Anyway for better lens comparisons, I'd recommended www.photozone.de - which is WAAAAAAAAAAAAAAY better than Ken Rockwell's reviews.
18-200mm will be more versatile
The versatility you speak of is pretty subjective IMHO. Other than focal length convenience... it does nothing to beat 18-55/55-200 in terms of sharpness, not to mention the barrel/pin-cushion distortions comparisons which is horrid on 18-200mm... And for a slow lens it can't even beat the bokeh "punch-out" of the 50mm f/1.8D...
Price of 18-200 allows you to get 55-200mm, 50f/1.8D or G, 35f/1.8G and even possibly a SB400/600 (to stretch it a little)? All of which are little unpolished gems by themselves...
The absence of the "-S" (or "-I") identifier means the lens has no built in motor.
I think it just so happens that there isn't an AF-S _____ D lens
Btw.... YES, I think there are AF-S _____ D lenses.
AF-S 17-35mm f/2.8D
AF-S 80-200mm f/2.8D
*phew* luckily my knowledge of lenses isn't too limited...
Last edited by kriegsketten; 12th September 2011 at 11:17 AM.
Sad to say.. 18-200 is only a convenience lens. It's sharpness lose to a 200buck 55-200mm. Likewise for the Af speed.
D700 - 24-70mm F2.8 ED - 105mm VR2 Micro - Samyang 14mm - 50mm 1.8D - Mb 10 - SB900 - SB400
Used the 18-200 when I owned D300 back then, but sold it after I upgrade. That being said, I say it is better than 55-200. Seriously what I will advice to be more of a concern on a DX lens is between 18-55mm. Anything more, I suggest you move in and don't stand there. If you wanna reach beyond 100mm, you better have a good lens with fixed aperture. Else in any case you are either stuck with f/4 and smaller aperture or the quality degrade.
If one value composition more than quality, I say use the 18-200 and move in until you can frame your subject between 18mm and 55mm. I assure you will appreciate the output more because near objects gives a better perspective, in my opinion. They are distorted in some sense with the edges of the frame stretches more, but isn't photography about capturing the moment, and also view things in a radically perspective from what your eyes can do ? it gives the art behind the glasses.
For my gear now, I say 24-70 is the most versatile, reaching far and beyond will depends on the subject. If it's a lovely bird, you probably need 400mm and beyond. If it's a person, I'm curious why you are standing so far away. If it's a building, shouldn't you move nearer and capture with a wide angle like between 12mm and 24mm (FF). If it's a facial expression and you cannot get near, 200mm at f/2.8, not much lens out there does this, is your best option and it ain't cheap.