canon10D

is this blurry enough??

I was using 300mm prime lens f-stop at 2.8

canon10D

what the hack....I will post a few more......

haha

jake123

Having nice out of focus effects requires a lot of skills (which I don't have) like the distance between background and subject, less "busy" background, etc..........

jake123

原帖由 daimo 於 2008-7-24 14:01 發表
The longer the focal length and the larger the aperture the more shadow the DOF, i.e. more blurred backgroud.

In other words, if you use a wide angle then it is much harder to achieve blur background ...

And also the closer you focus, the less depth of field(which is the problem he/she is experiencing - full body portrait too much dof, half body shallow enough dof.

jake123

原帖由 daimo 於 2008-7-19 14:03 發表
It's not just the crop factor that matters ... a model taken by a 50mm vs a 85mm vs a 135 mm vs a 200mm, even if you use PS to crop it down to the same size, the pictures won't look the same.

Other than deeper depth of field(about one stop more for crop?) and the characteristics of the lenses themselves, what are the differences?

kisstherain

原帖由 jake123 於 2008-7-28 17:47 發表


Other than deeper depth of field(about one stop more for crop?) and the characteristics of the lenses themselves, what are the differences?

What is "one stop more for crop"?

Catpiano

KTR, I think he means for APS camera .. the DOF is based on different calculation ..  

IE ..  take 2 pic, one with 85mm F1.2 on FF (36x24)  vs one with 50mm F1.2 on 1.6x crop (say 40D), which kind of ..  = 80mm  ( but not really )    even both pictures will look kind of identical ..  but diff DOF, the one with 85mm will be more SHALLOW ...   so I guess he means with APS camera, the DOF need to be added ?   ( I dont hv the calculation in my brain .. ask SB .. lol )

Anyway ...  

Catpiano

Oh ...  KTR .. let me use Nikon as example ..   

Kind of like D300 + 135 F2  vs D700 + 200 F2 ..

jake123

原帖由 kisstherain 於 2008-7-28 20:16 發表


What is "one stop more for crop"?

By that I just meant you should get around same depth of field if you close the aperture down one stop. I have no idea how true that is now that you've asked.

shutterbug

hm...I think it goes like this....

Basically, you get the same DOF using the same lens if you shoot from the same distance, no matter what sensor size you have (crop or FF).  The difference in what people see in DOF is probably because they usually need to stand back further from the subject using crop body so the DOF is not as shallow.