landscape : 16-106
potrait : 17-50

so buy both...

buy this one....1680      

well... best sugestion is to buy both... but seeing as budget would be a problem, get the 16105 1st because of the range. then, can save up for the 1750... doing that right now...

yuenzhi: 16105..i just dont like 1750 hahaha

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Added on August 14, 2009, 3:39 pm
true..   .and try avoiding black backgrounds

SAL 16-105 and SAL 16-80z actually not much dif...at least for my eye. i will not pay extra 1k for the not much dif and shorter range. i would rather use the 1k for other stuff

yuenzhi: i love my 16105

if u wanna see sample (posted b4)

http://www.flickr.com/photos/26361657@N08/...57621805951481/

^ It is quite hard to spot difference in quality. Dont worry...

lol...16105 is a lens tht is slightly better than ur kit lens...yes there is difference. U zoom into ur photo and u spot tht 16105 is slightly sharper. Don expect buying a lens then ur photo will look good..must see lighting and other minor stuffs also.

FYI, 16-105 was a kit lens for A700 in europe region (correct me if I am wrong)..

and I dont think the image quality of 16105 matches 1680cz quality .. but of course, it is better than kit lens (18-70 in this case) .. ..

mind to share your photo taken by 16105? maybe 16105 users have experience in checking the lens problem, etc .. ..

its suppose to be 1680 successor..but somehow carl zeiss doesnt approve it and hense sony sell it as a sony lens....so whats the big deal btwn carl zeis or not??i believe the coating plays a part..
the contrast kills the details in the back area...the body of the dog almost couldnt see any details anymore....
anyway..quality aside...try to experiment in different compo...the tail of the dog was cut...and i feel that the angle was a lil bit awkward too 
just my 2cents worth..

well..i cant comment on that because i dont own any 16105..and i never joint any TT/classes..so i had no chance even just to try it..lol

but well feel free to see my album...most of the photos r taken with tamron sp90 or cz1680..

just messing around with editing..lol..

just messing around with editing..lol..

make selection and do blur effects such as motion blur etc.. on photoshop

do some feathering and the result would be good

bokeh is something we couldnt really imitate...u could make it blur..n fool all the ordinary ppl that dont do photography...but after u did it a few times..u'd notice...thats "blur"..not "bokeh"

hi yuenzhi - i ve been analyzing yr pics - here - suggestions from a noob too -

yr exif for the dog pic as shown - 1/30, f3.5 iso 100

yr exif shows that u r using shutter speed of 1/30, normally at that shutter speed its too slow for non posing animals and humans like children (at least 1/50 above if the object can move), ...yr f also shows 3.5 which can capture more lights but your dof will only able to make smaller parts in focus. In your framing the whole body of the dog comprise at least quarter of the pic. At 3.5 with that distance between you and your dog, not all the body of your dog will be in focus thus only small part will be lens sharp, (in the dog case and distance i would prefer  f5 and above). At your setting a slight shake or movement on the subject part will make yr subject not as sharp as you wish. As your shooting is indoor i think u hv no choice but to illuminate yr subject at that setting. That is how a flash (an external flash is better) comes in handy and you are able to hand held yr camera with faster shutter speed and smaller apperture, or if u dont use a flashgun, you can increase yr iso to brighten yr subject but too high an iso will give you undesirable noise . You can set all yr setting as desired with Manual mode  (I suspect u r using  P mode). A proper setting with the help of flashgun will reduce yr amount of time on editing and give u better overall result.
Just my noob opinion.

play with ur lens and find ur sweet spot of ur lens...looking at ur Doggy pig, as what napi said, speed too slow and wide open....

if indoor, try to shoot some object with good lighting... and zoom in...and yes the 16105 are not very much better then kitty, our kitty can be very sharp too...if u know how to use it.

1 more opinion, do feel scare to pump out ur ISO