View previous topic :: View next topic |
Author |
Message |
stingOM
Joined: 27 Sep 2007 Posts: 3168 Location: Ireland
Expire: 2012-12-27
|
Posted: Wed Nov 17, 2010 5:58 pm Post subject: Tamron TV lens 16mm f1.8 |
|
|
stingOM wrote:
Hi,
I received my c-mount adapters today. Two versions - one flat version and another with a lip. Both does not allow the Tamron TV lens to focus to infinity with my Panny G1 to my disappointment. Also the sensor coverage is not great - but I had expected this anyway. I noticed there is lip (inner circle) on the lens mount (it is not flat). I wonder if it was filed away will it bring the lens closer to inifity focus? I don't really want to destroy the lens.
Lens is very well constructed, with smooth focusing helicoid. I don't know which version it is, but according to Tamron website:
http://www.tamron-usa.com/about/history.asp
It is suppose to be the 16mm F/1.8 for 1” Vidicon are the first CCTV lenses made by Tamron. If I am correct.
Any thoughts or info on this lens?
Thx
Last edited by stingOM on Wed Nov 17, 2010 10:33 pm; edited 1 time in total |
|
Back to top |
|
|
Attila
Joined: 24 Feb 2007 Posts: 57849 Location: Hungary
Expire: 2025-11-18
|
Posted: Wed Nov 17, 2010 10:24 pm Post subject: |
|
|
Attila wrote:
Looks a nice piece, finger crossed to solve infinity problems. _________________ -------------------------------
Items on sale on Ebay
Sony NEX-7 Carl Zeiss Planar 85mm f1.4, Minolta MD 35mm f1.8, Konica 135mm f2.5, Minolta MD 50mm f1.2, Minolta MD 250mm f5.6, Carl Zeiss Sonnar 180mm f2.8
|
|
Back to top |
|
|
fatdeeman
Joined: 13 Jun 2009 Posts: 780 Location: UK
|
Posted: Wed Nov 17, 2010 10:26 pm Post subject: |
|
|
fatdeeman wrote:
Sometimes a stop screw in the focusing barrel can be loosened or temporarily removed and then you can focus past infinity but the only way to improve frame coverage is to have the lens physically closer to the sensor. _________________ - Dave
www.lensporn.net
www.flickr.com/photos/fatdeeman/
DSLR: Canon EOS 60D, Samsung GX-1S (Pentax *ist DS2)
Mirrorless: Panasonic DMC-G1, Sony NEX-5N
Compact: Canon PowerShot G3
Lenses:
Wide: Tokina RMC 28mm F/2.8, Tamron Adaptall 2 28mm F/2.5, Sun Optical 28mm F/2.5, Super paragon 28mm F/2.8, Sigma filtermatic 24mm F/2.8, Fujinon 35mm F/2.8, Sun Optical 35mm F/2.8
Standard: Industar 50-2, Helios 44-2, Helios 44M, Helios 44M-3, Pentax-M 50mm F/1.4, Pentax-M 50mm F/1.7, Pentax-M 50mm F/2, Ricoh 50mm F/1.7, Chinon 50mm F/1.7
Tele: Pentacon 135mm F/2.8, Pentacon 200mm F/3.5, Optomax 200mm f/3.5, Sun Optical 135mm F/3.5, Soligor 350mm F/5.6
Zoom: Tokina 28-70mm f/3.5-4.5 SZ-X270 SD, Sigma Zoom Pi 35-200mm F4-5.6, Sun Optical 28-80mm F/3.5-4.5, Sunagor 80-205mm F/3.8, Tokina RMC 80-200mm F/4, Vivitar 70-150mm F/3.8, Tamron 95-205mm F/6.3, Tamron Adaptall 28-200mm F/3.8-5.6 LD Aspherical, Tokina RMC 70-210mm F/3.5
Mirror: Falcon (Samyang) 800mm F/8, MTO-11CA 1000mm F/10, Tamron Adaptall 2 500mm F/8
|
|
Back to top |
|
|
stingOM
Joined: 27 Sep 2007 Posts: 3168 Location: Ireland
Expire: 2012-12-27
|
Posted: Wed Nov 17, 2010 10:31 pm Post subject: |
|
|
stingOM wrote:
Thanks Folks. I will give it a go. But I prefer not to damage the lens and sell it to someone who has the metal work skills to modify it.
At what point would you know that the modification is in danger of hitting the camera sensor?
I was looking at Industar 50 collapsible lenses. Then I realised it will damage the sensor if focused to infinity.
Just looking at the adapter again. It looks like the edge of the lens mount may be hitting the ridge of the adapter. I am not sure, but if you look at this post, you get the idea:
http://forum.getdpi.com/forum/showthread.php?t=8062&highlight=cosmicar |
|
Back to top |
|
|
stingOM
Joined: 27 Sep 2007 Posts: 3168 Location: Ireland
Expire: 2012-12-27
|
Posted: Wed Nov 17, 2010 10:44 pm Post subject: |
|
|
stingOM wrote:
OK, I checked it with my digital caliper. The outer most diameter of the lens mount is 38.30 mm, whilst the inner opening of the c-mount adapter is 37.3mm. So it is colliding and preventing the lens from turning inwards correctly.
Correction can only be made on the lens side, as the c-mount adapter is too thin to modify.
A lot more detail is give here (thanks to another forum post)
http://cjeastwd.blogspot.com/2009/06/adapting-lens-to-fit-mount.html |
|
Back to top |
|
|
Nordentro
Joined: 24 Jun 2010 Posts: 4713 Location: Lillehammer, Norway
Expire: 2015-01-29
|
Posted: Thu Nov 18, 2010 3:03 am Post subject: |
|
|
Nordentro wrote:
This is a known problem, I had the same difficulties with my Fujinon 25mm. You can see the thread here _________________ Lars | Manuellfokus.no |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|