Theoretical Stacking (1 Viewer)

Sy V

Well-known member

• Mar 17, 2009

• #1

Is there anything to prevent the stacking of a teleconverter (to increase focal length) with an extension tube (to decrease minimum focus range) in theory?

If theoretically possible would it be assembled, camera body-extension tube-teleconverter-lens?

Perhaps this is common practice that I've not heard of before.

Just thinking out loud and perhaps a little outside the box...

Simon

 

hollis_f

Well-known member

• Mar 17, 2009

• #2

Sy V said:

If theoretically possible would it be assembled, camera body-extension tube-teleconverter-lens?

Click to expand...

Never tried it but that's the arrangement I would try first.

 

JohnZ

Well-known member

• Mar 17, 2009

• #3

Simon, Why would you want to do this ? I thought the idea of a TC was to increase the focal length of a lens. To then add an extension tube would, possibly, decrease the minimum focus distance but to what end ?

 

postcardcv

Super Moderator

Staff member

Supporter

• Mar 17, 2009

• #4

JohnZ said:

Simon, Why would you want to do this ? I thought the idea of a TC was to increase the focal length of a lens. To then add an extension tube would, possibly, decrease the minimum focus distance but to what end ?

Click to expand...

Indeed the tc will increase the focal length while the tube will decrease the min focus distance, ideal if you want close up shots of small subjects. I have done this in the past and it works well, though you do need to watch the DOF which can get very thin with high mags at close range. This shot was taken with a 500 f4, 1.4x tc and 32mm of extension tubes - http://www.birdforum.net/gallery/showphoto.php/photo/168078/ppuser/3294

 

JohnZ

Well-known member

• Mar 17, 2009

• #5

Thank you for the explanation Peter.

 

Sy V

Well-known member

• Mar 17, 2009

• #6

John

Peter's summed it up perfectly.
Although I was just theorising - I never expected to see an example of the practice... and what an example too!

Thanks all.

 

C

Claymore

Well-known member

• Mar 18, 2009

• #7

postcardcv said:

Indeed the tc will increase the focal length while the tube will decrease the min focus distance, ideal if you want close up shots of small subjects. I have done this in the past and it works well, though you do need to watch the DOF which can get very thin with high mags at close range. This shot was taken with a 500 f4, 1.4x tc and 32mm of extension tubes - http://www.birdforum.net/gallery/showphoto.php/photo/168078/ppuser/3294

Click to expand...

Oh dear something else to try out LoL cracking shot! now where did I put my extension tubes? mmmmmmmmmmmmmmmmmmmmmm
Brian

 

P

paul goode

Well-known member

• Mar 18, 2009

• #8

Totally agree with Peter, its a technique I've used a lot with woodland birds.

 

a.dancy

Registered User

• Mar 18, 2009

• #9

That desert wheatear is a lovely shot Peter.

 

Jaff

Registered Member

• Mar 20, 2009

• #10

Tim Taylor uses the same technique for quite a bit of his macro work. Although I can't see you'd really need the combo of teleconverter + ext tube on something with a pretty good close focus as a 100-400mm, ext tubes certainly are a benefit in the right situation but both would result in a great loss of light and shutter speed.

I took this with an ext tube on http://www.birdforum.net/gallery/showphoto.php/photo/222117/ppuser/42340 but as you can see I had to brighten it up a little. If using ext tubes in Av you might want to adjust your exp comp to compensate for the reduced light hitting your sensor. Something I forgot to do. |^|