Lens fitting ... help needed

[Maltesekilli]

Hi,

I own a Sony A100, and recently bought a Minolta MD 28mm f/2.8 lens for it. Since the lens bought is M49 and my SLR is M55, I needed a step-down ring .. am I right??

So, I also bought the step-down ring. I also bought a Minolta MD/MC Lens to MA Dynax Adapter for Sony Alpha. Guess this was also needed, or not??

Is the equipment mentioned above all needed to use the lens? And if yes, how the hell do I set it up all together lol??

Guess no need to tell you I'm totally new to this lens fitting stuff. it shows

[Lee Sacrey]

I am not complete sure as I don't use any MD/MC lenses with my a100 but, I understood that just 1 adaptor was needed. Here is a website for one. I thought if you had this it was all that was needed. Good luck.

http://haodascreen.com/minoltaMDAF.aspx

[Maltesekilli]

Hi Lee,

The item shown in the site provided is identical to the Minolta MD/MC Lens to MA Dynax Adapter for Sony Alpha I have. However, since the camera is made to fit M55 lenses and the lens bought is M49, wouldn't I need the step-down ring or not?

[DonSchap]

Using MC/MD lenses on your new digital will be challenging, as it normally offers no aperture information the computer for exposure calculation. Also, it is all manual focus when you do. One of the main issues with that is that the A100 has no split-screen focus assist to help. Its your raw eye trying to determine proper focus .. and more often than not, you will be off.

My recommendation is to get your hands on a "kit" lens, if funds are tight.



They are "almost" free in most parts of the world and on eBay. If the money is NOT tight ... I suggest getting a TAMRON SP AF 17-50mm f/2.8 SP Di-II LD lens and you will have a dandy set up. It shoots about as sharp as a reasonably priced zoom can do and offers nearly the same performance as a MC/MD 28mm f/2.8. And the best part ... no adapter!

[inkista]

Originally Posted by Maltesekilli

I own a Sony A100, and recently bought a Minolta MD 28mm f/2.8 lens for it.

MD/MC lenses on the Alpha mount are problematic. It's the Minolta AF-mount lenses that will mount directly to a Sony Alpha. The older MD/MC mount was shallower from the image plane to the back element of the lens--so can't use a simple metal ring to adapt and maintain inifinity focus. So you have to get an adapter with a glass element in it, and just like a teleconverter, that will rob you of image quality. Still might be worth it, though.

Because the lens can't talk to the body, though, you will lose the ability to shoot in any modes other than full manual and aperture-priority, autofocus, and possibly metering. That's what you give up when you go for the vintage glass bargains.

Since the lens bought is M49 and my SLR is M55, I needed a step-down ring .. am I right??

You got a little terminology confusion here. The M49/M55 you're talking about is the filter size--it's the diameter of the front filter thread in millimeters. It doesn't have anything to do with the back end of the lens. A step-up/step-down ring is for adapting a differently-sized filter to a lens.

It's easy to get confused about this, because back in the day, the really old mount systems were also just threaded holes of a certain diameter. And two of these mount systems are called M42 (aka "screw-mount Pentax") and M39 (rangefinder, aka LTM, aka Leica Thread Mount aka Leica screwmount).

BTW, you can adapt M42 lenses to the Minolta AF/Alpha mount with a simple metal ring, which won't rob you of image quality. A lot of folks are snapping up the M42-mount Takumars and Carl Zeiss Jenas for adapting (just check they're not Pentax K-mount or Contax/Yashica mount, respectively).