Interdimensional portal.

[James T]

Both shot using Intrepid 5x4 Mk 3.5 (i.e. Mk3 with Mk4 base) and Intrepid pinhole on Fomapan 100, with the effective focal length varying from about 100mm to a bit over 200.

6 ½ min exposure, with a half turn of the focus every 15s going 100 → 200

8 min exposure with a half turn every 20s going 200 → 100.
Both processed in ID-11 stock 9th use, 9:30 @ 22°C.

 

[Ian Grant]

Interesting technique, well done.

Ian

 

[David M]

That's a very curious and interesting use of long exposure. Shall we be seeing more?

 

[Keith Haithwaite]

An interesting LF version of the 35mm technique of zooming during an exposure, very popular in the 1970-80's with a brief revival in the 90's and noughties with Star Trek connotations as I remember.

 

[James T]

They were originally shot for a TIPF weekly challenge on the theme of intentional camera movement (I used the second one). And yes the idea was to mimic cheesy 1970's sci-fi special effects.
The extreme non-reciprocity of Fomapan made life a lot easier, the metered exposure near the middle of the sequence was 30-45s, which would have been far too short to control the focal length effectively.
My first idea was a speed limit sign, so if I can find one where I won't get run over maybe...