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Macro Lenses

Started by brucesdad13, 06/08/2015 07:21PM
Posted 06/08/2015 07:21PM Opening Post
I've been wandering around the local yard sales and flea markets with the wife on weekends. Keeping my eyes open for a random reflector telescope that will probably never materialize. I have been running into LOTS of old cameras. What I've discovered is that my T-adapter that I use to connect my DSLR to my telescope doubles as an adapter that I can use for a lot of these lenses from the 70s and 80s. Sunday, I bought a Sigma f/3.5-4.5 28-70mm Macro Zoom lens for $10 and the guy threw in a Super Multi-Coated (SMC) Takumar f/2 55mm (Asahi Optical Co.). I found out that the Takumar is likely radioactive and contains thorium.

Anyways, the T-adapter I have doesn't get the lenses deep enough into the camera to achieve infinity focus. They still work fine for close up if the lens is very close. I ordered a small adapter that will hopefully to the trick. Here's the Takumar (photo). I've mostly been using the Sigma which seems more versatile. Taken some photos of flowers and insects which I'll post to get this forum going again.

Attached Image:

brucesdad13's attachment for post 59460

~ Charlie Stevenson

8" f/5.7 String Telescope - 1st Scope Build; 2nd Place Stellafane 2016 Optical Award for Newtonians 12.5" and Smaller
10" f/4.5 Newtonian (June 2015) mirror refigured by Optic Wave Labs P-V WaveFront 1/14.24, Strehl Ratio 0.993 (Aug '15)
Criterion RV-6 seems to be circa 1973 (June 2015) [For Sale]
Celestron C8-A XLT (January 2015) [For Sale]
Celestron PowerSeeker 70AZ (Christmas 2014)
Aldrich Astronomical Society member since 2015
http://astro.charleskelleystevenson.com/
Posted 06/08/2015 07:23PM #1
And here's the Sigma lens from the flea market (photo)

Attached Image:

brucesdad13's attachment for post 149716

~ Charlie Stevenson

8" f/5.7 String Telescope - 1st Scope Build; 2nd Place Stellafane 2016 Optical Award for Newtonians 12.5" and Smaller
10" f/4.5 Newtonian (June 2015) mirror refigured by Optic Wave Labs P-V WaveFront 1/14.24, Strehl Ratio 0.993 (Aug '15)
Criterion RV-6 seems to be circa 1973 (June 2015) [For Sale]
Celestron C8-A XLT (January 2015) [For Sale]
Celestron PowerSeeker 70AZ (Christmas 2014)
Aldrich Astronomical Society member since 2015
http://astro.charleskelleystevenson.com/
Posted 06/09/2015 07:06AM #2
The transition from film to solid state is fascinating. "Full Format" film was most always 24x36mm and the 1st CCDs were microscopic, coarse and obscenely expensive. The chips gradually got bigger Bigger BIGGER and cheaper Cheaper CHEAPER...until now "Full Format" chips with magnificent performance are available in what emulate the old high-end film-based SLRs. So suddenly those old, magnificent lenses are the Perfect Match again! I have a nice compliment or great old minty Olympus (manual) lenses, including the coveted 100mm F/2 that cost $$$ originally and the very best Nikon. The greatest irony is that Kodak pioneered the very best chips (their KAF series) still preferred by high-end users today (for uniformity, low noise and freedom from defects). Yet as film precipitously faded from the scene...the company all but folded. I worked for Kodak and witnessed uncountable rounds of layoffs (luckily evading the shrinkage). Fortunately, I was on the government contracts side of the business, which had gone solid state WAY before the commercial market did. Tom

29-inch Dob in a dome
36-inch upgrade soon
LUNT 80/80 solar scope
FLI 6803 cam
APM 100mm APO Binos
JMI RB-16 Night Vision Binos
Zeiss 20x60 IS binos