Lens on eBay and newbie DOP question

Archived from groups: rec.photo.digital (More info?)

I found that eBay sells a lot of Canon A80 lens. For example,

http://cgi.ebay.com/ws/eBayISAPI.d [...] 43806&rd=1

I can get wide angle lens, telephoto lens, lens adapter, filters, mini
tripod, lens cleaning kit for $100. I know they are not professional lens.
But are they any good relatively? Does anyone have any experience with that?

I would like to get more shallow depth of field on my A80. Will a 2X
telephoto help a lot? I assume it is telephoto not wide angle lens that will
create a more shallow depth of field.

Thanks for your help.

Archived from groups: rec.photo.digital (More info?)

On Sat, 21 May 2005 06:43:38 -0700, in rec.photo.digital "Bill"
<bill@nospamland.com> wrote:

>I found that eBay sells a lot of Canon A80 lens. For example,
>
>http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=30066&item=7517343806&rd=1
>
>I can get wide angle lens, telephoto lens, lens adapter, filters, mini
>tripod, lens cleaning kit for $100. I know they are not professional lens.
>But are they any good relatively? Does anyone have any experience with that?
>
>I would like to get more shallow depth of field on my A80. Will a 2X
>telephoto help a lot? I assume it is telephoto not wide angle lens that will
>create a more shallow depth of field.

I have no idea of the quality of the above. I've always used Nikon
converters, though not cheap.

From http://www.normankoren.com/Tutorials/MTF6.html
For a specific format, depth of field, expressed as distance, is
independent of focal length. But depth of field, expressed as a percentage
of the distance to the subject (Total DOF/s %), is inversely proportional
to focal length. It can be very small for long telephoto lenses.

So with the 2x you have doubled the distance from which you can take a
photo halved the DOF taken for a given coverage.

Examples taken with Nikon CP-990+TC-3:
http://edwardgruf.com/Digital_Phot [...] 39_JPG.htm
http://edwardgruf.com/Digital_Phot [...] 20_JPG.htm
----------
Ed Ruf Lifetime AMA# 344007 (Usenet@EdwardG.Ruf.com)
See images taken with my CP-990/5700 & D70 at
http://edwardgruf.com/Digital_Phot [...] index.html