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blibecap

Member Since 28 Mar 2004
Offline Last Active Jun 20 2017 02:31 PM
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Posts I've Made

In Topic: Nikon 8-15mm in the house!

20 June 2017 - 02:29 PM

Usable range on FX will be based on having a dome with a removable sunshade. This will be needed from 8mm through to around 13mm. 

 

On DX, the lens partially vignettes at 8 and 9mm, before offering usable image from 10 through to 15mm.

 

Pool testing on Sunday....

 

Adam

 

 

 

 

 

 

 

 

Isn't the vignetting caused by the fact that the dome is not in the propler location and the lens is seeing the backing plate for the dome? 


In Topic: Nikon 8-15mm in the house!

19 June 2017 - 06:13 PM

Some good news is that on my (Seacam) set up, the zoom ring for the Nikon 10-24mm works beautifully with this lens!

 

I'll be shooting it tomorrow with a Fisheye (4") port on the D500 and a Compact (7") port on the D810.

 

 

Is there any specific way of calculating this, or is to just trial and error?

 

Adam

 

Yes here is a link to the solution. http://archive.bigbe...hoto/nodal.html it helps if you have a camera rail to make this measurement.

 

http://www.ebay.com/...y-/381975930317

 

The measurement is from the back face of the lens (where the lens face meets the camera face)(see below) to the nodal point. 

 

  Lens Focal Length Entrance Pupil Length (L2)

 

Original equipment
(Lenses from same manufacturer as camera) Enter the exact lens name, or if you are using a camera with a fixed lens the name of your camera as mentioned at DPreview.

 

EPDB-length2.jpg Facing the side of the lens, the distance from the base of the lens to the Entrance Pupil. A negative value means the entrance pupil is outside the lens, in the camera body. Such is the case with many telephoto lenses. The lens base is the point on the lens that contacts the "lens base" on the camera used to determine the "Tripod mount length (L1)" in the table above.


In Topic: Nikon 8-15mm in the house!

19 June 2017 - 10:42 AM

it would be nice to know the nodal point


In Topic: Ikelite Package for D7000 - $1,500

22 May 2017 - 01:01 PM

you forgot a zero in the camera list, it is a D7000 Camera not a D700 Camera

 

Bill


In Topic: Balancing a positively bouyant dome

08 May 2017 - 02:15 PM

Try to determine how much weight you will need to make the dome neutral in the water because you may not have enough room for the weights.  Do not put the weights on the inside of the shade as they may show up in your picture. The other problem you have with that solution is they are not removable for transport, Over under pictures etc.