B300+250D, AF works perfect

Started Mar 17, 2001 | Discussions thread
ForumParentFirstPrevious
Flat view
Carlos Methfessel Regular Member • Posts: 118
B300+250D, AF works perfect

The last time I wrote about the B 300 on G1 was because I tested it to see if this " Coment" from Tom Wheland on an other Forum was right:

"Teleconverters and aperture: good news

I've been reading about teleconverters, and just found out something new and welcome. Of course, they multiply the focal

length of your camera (for a B300 and a G1, 1.7x102mm = 174mm). But they also multiply the F stops.

A G1 has a very usable but fairly narrow range of aperture from F2 (or F2.5 in telephoto) to F8. With a B300 in place, the

available aperture range changes to F4.2 to F13.6 at full telephoto. What you lose in speed (and longer exposures) you gain

in depth of field. That's great news for depth of field junkies like me. So I'm going to put the B300 on sometimes just to get
the small aperture."

The tetst schowed that hi must be right about this to the point that I have not experiensed any longer exposures, it seems tha there is allmost no light loss on this combination.

Since the 250D (or any +4 closeup lens) gave me only 0,8cm of sharp depth, I have tested yesterday the combination with the B 300. It seems to work, I could say that the deepness rises to about 1,5 cm at same F stop ( 2,5 - the light abaylable did not allow more, wich would rice this a lot).

Here a result with this interesting DOF (allmost what you get with an expencive SRL )

http://albums.photopoint.com/j/View?u=932331&a=6813802&p=43960483&Sequence=0&res=high

Or one with higher F stop (trying to get a bee while flying)

http://albums.photopoint.com/j/View?u=932331&a=6813802&p=43895020&Sequence=0&res=high

I am not totally shure about this, but it really seems to work, to bad that the wheather (cloudy again) does not permit to experiment more. Yesterday I thought that we were in spring allready, today and the next days we are back in winter again here in Germany

If any reader haves more knowlege about this f stops change, it would be nice if he or she explains this. (Pekka??)

Carlos

ForumParentFirstPrevious
Flat view
Post (hide subjects) Posted by
(unknown member)
Jon
Bob
ForumParentFirstPrevious
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow