| Posted By |
mlag
[Profile]
[Gallery]
| Original Filesize | 356.6 KB | | Category | Miscellaneous Photos | Original Dimensions | 1479 x 800 | | Date Posted | 08-12-2021 | Number Of Views | 220 | | Average Rating |  | Number Of Comments | 0 | | Title |
caruba ext tube contacts compared to to pentax TC
| | Description |
The third lens contact (counting counter clock wise) of the Caruba 25 mm tube extender pentax chrome ( ET-PC ) is not recessed like on a camera body or on the pentax teleconvertors (1,7x , left in picture) .
For lenses with contacts it works fine. It has both contacts on the ring and the 2 inner contacts.
For lenses without contacts (like 'vintage' pentax-k and pentax-m generations) the lenses show up as with minimum aperture of f1.2 and trigger automatic metering (in stead of using the normal 'stop down' metering for this type of lenses.
There are two workarounds :
- cover the 3th contact and use stop down metering as usual for lenses without contacts.
- work with automatic metering but do following steps :
1) use +/- EV to correct for the minimum aperture (on my F4 lens i use EV -3 setting)
2) set manually aperture on camera to the aperture set (also manually) on the lens with the aperture ring.
in most cases this keeps algoritme in my K3II aligned with the characteristics & settings of the lens (actually you override the fake information from the lens contacts.... do not use a mode that allows to change automatically the aperture.... )
2.12.0.0
| | Camera | k3 II | | Lens | sigma 17-70 HSM | EXIF Information: | File Name | IMGP9789__5_.jpg | File Size | 365176 Bytes | | File Date | 2021:08:12 15:30:14 | Camera Make | RICOH IMAGING COMPANY, LTD. | | Camera Model | PENTAX K-3 II | Date/Time | 2021:08:12 08:50:10 | | Resolution | 1479 x 800 | Flash Used | No | | Focal Length | 19.0mm (35mm Equivalent: 28mm) | Exposure Time | 0.0080 s (1/125) | | Aperture | f/4.0 | ISO Equivalent | 800 | | White Balance | Auto | Metering Mode | pattern | | Exposure | Action Program (based towards fast shutter speed) | GPS Latitude | ? ? | | GPS Longitude | ? ? | GPS Altitude | 15.20m | | Lens | Sigma 17-70mm F2.8-4 DC Macro HSM | C | | | Links to Photo: |
Filmstrip
mlag's Photos - Miscellaneous Photos - "caruba ext tube contacts compared to to pentax TC"
