Shooting macro with the 105mm and 2xTC

[herbko 0]

Is it fair to run those two calculations at the same distance? isn't the nikon more like a 150mm on the cropped sensor, so to make it apples to apples, I'd change the distance or change the lens, just for the calculation.

 

But the point really is, yeah, the nikon has less depth of field, but it has more power, and power matters. The nikon is not giving up something and getting nothing in return.

 

And even if it was, some people are going to like shallow depth of field. I really like it on the images with the polyps out.

 

I'm having trouble with the quoting, but people have done this with film, I think Chris Bangs has. His macro canon needs a weight belt, not a bouyancy collar.

 

Chris Bangs' rig

 

Chris Bangs' anemone fish eggs at 8or9:1

 

Chris Bangs gallery

 

an old description of his rigs I saved:

 

Cameras used, Fuji -S2 ,Nikon F-5,N-90,or 8008

Aquatica housings, Ikelite was used with the N-90 for up to 5:1

custom ports built using multiple extensions

Lens - Nikon Macro lens 105 mm or 200 mm

Kenko PRO 300 teleconveters ( 1.4x/2x/3x. single or stacked )

Multi element diopters as required for magnification

Note: your images can only be as good as the glass you use on the camera, the camera itself is not nearly as critical!

Strobes, Dual Ike 50, or Nikon SB-105 ( full manual mode )

<{POST_SNAPBACK}>

 

 

Chris Bangs' shot has the EXIF info posted below the pic.

It's shot with a S2 pro, 105mm lens at F/16. Assuming you are correct about the Kenko teleconverter (a 2x), that would make the actual F-stop F/32. At that F-stop, the aperture ( the little hole in the diaphragm ) is the optical element that is the limiting factor not the glass, any of the popular macro lenses will have about the same performance. Also, you are right that the camera is not as critical, a 12M pixel D2X would not show higher resolution than the 6M pixel S2 pro.

 

Larger format helps, but only a little. I posted an anlysis here:

 

http://wetpixel.com/forums/index.php?act=S...t=20#entry80286

 

It's a tradeoff between DOF and resolution. It's interesting to note that the focal length of the lense does not affect the outcome. That is for a given magnification, you'll get the same DOF at the same F-stop independent of focal length.

[Claude 0]

Chris Bangs' anemone fish eggs at 8or9:1

Hi Roger,

Could you explain how you got 8 or 9:1 for that picture ?

Thanks

Claude

[RogerC 4]

Claude, Herb, the link titles and the bottom block of text are all from Chris Bangs. His rig always fascinated me and I've saved a couple clips on it and links to it, just thought I'd paste them in here. THe 8 or 9:1 calculation is his, the quote on lenses is his.

 

Herb, doesn't focal length matter in one parameter: you can stay farther away form the subject with a longer lens to get that same magnification of DOF, or am I missing something?

[herbko 0]

Herb, doesn't focal length matter in one parameter: you can stay farther away form the subject with a longer lens to get that same magnification of DOF, or am I missing something?

<{POST_SNAPBACK}>

 

No. If you use a longer lens you have to move further away from the subject to get he same image for the parts in focus. Longer lens have less DOF for a given distance from the lens but DOF increases with subject-lens distance and the two cancels.

[hoovermd 0]

I've got a Canon 100mm macro on a 5D body and am considering the Canon 500D Close-up Lens on the front of this for super-macro.

 

Any opinions???

[herbko 0]

I've got a Canon 100mm macro on a 5D body and am considering the Canon 500D Close-up Lens on the front of this for super-macro.

 

Any opinions???

 

I frequently use the 500D with the 100mm macro. It works very well. The 500D is a +2 diopter and will limit focus to 1/2 meter or closer.