Minolta lens conversion for A700 with ROM chip keeps focus and IS

It's a little jargon heavy, but Dyxum forum moderator Shao Z. has documented the process of modding up some 60's era f/1.2 Minolta lenses and setting them to work with his Sony A700 DSLR. Obviously the Sony Alpha series comes from a Minolta heritage, but it took adding a ROM chip and machining some mounts to get the lenses to work with the A700. The plus side is that the process keeps infinity focus and focus confirmation intact (the lens itself is manual focus), as well as Sony's in-camera Super Steady Shot. The lenses work with all Sony DSLRs, as well as the Minolta 5D and 7D film cameras, and he's selling one on eBay if the whole modding experience isn't your thing.

[(Unverified) Posted Apr 4th 2008 9:43AM]

That simply gives me a big fat ol' chubby.

http://www.johnwaller.org/photo/

[wyldtek Posted Apr 4th 2008 9:55AM]

It makes me want coffee

[(Unverified) Posted Apr 4th 2008 10:02AM]

This looks like an easy DIY project for the weekend

[(Unverified) Posted Apr 4th 2008 10:06AM]

5D and 7D are not film cameras for goodness... they are DSLR from Minolta

[(Unverified) Posted Apr 4th 2008 10:06AM]

Why didn't the camera makers produce a 'data back,' to help convert film type cameras to digital???

[(Unverified) Posted Apr 4th 2008 10:08AM]

wow, cant believe that! There's a new lawsuit right now against APPLE because they use cheaper TN panel in the 20inch models Imac, only capable of 6-bit-per-pixel color, 98% fewer colors than Apple advertises, and Engadget post stuff like this!

sad...
still a nice story Paul... sorry to hijack the post, couln't resist!

here the link to Appleinsider;

http://www.appleinsider.com/articles/08/03/31/apple_hit_with_another_millions_of_colors_lawsuit.html

[(Unverified) Posted Apr 4th 2008 10:42AM]

"wow, cant believe that! There's a new lawsuit right now against APPLE because they use cheaper TN panel in the 20inch models Imac, only capable of 6-bit-per-pixel color, 98% fewer colors than Apple advertises, and Engadget post stuff like this!"

Putz.

[moijk Posted Apr 4th 2008 10:46AM]

I have this lense, the 55mm f1.2 that minolta created in the 60s and 70s. I have conveted it to work on the Alpha series but that without the electronic contacts so i do not get the af focus confirmation nor IS - so this would be a huge upgrade. but it is so fast it is easy to miss focus so this would be great!

[moijk Posted Apr 4th 2008 10:47AM]

It is by the way one of the lenses with the best bokeh ever made. It is a masterpiece in that area.

[CRA1G Posted Apr 4th 2008 11:25AM]

Mmm...bokeh...

[(Unverified) Posted Apr 4th 2008 11:44AM]

"Bolt on replacement"...must be tough little screws. "Custom lens ROM chip." It might emit Snackyon particles too. Come on people. HTF does a rom chip confirm focus? no really...unchangable memory location 0000: 1 = focused....BS.

[(Unverified) Posted Apr 4th 2008 12:58PM]

You beat me to the punch. Last I looked my 5D and two 7D bodies were digital.:)

[(Unverified) Posted Apr 4th 2008 1:49PM]

"Bolt on"? Bolton? Who had to grad No-talent Ass Clown into this???!?!1

[(Unverified) Posted Apr 4th 2008 1:57PM]

did i just say grad instead of drag? is it possible to _become_ dyslexic?

[(Unverified) Posted Apr 10th 2008 5:28PM]

Uh, because the chip stores lens information sent to the camera body, and the camera uses that information to achieve focus. The body image stabilization also uses the focal info to determine how much shifting to do with each lens.

[KAL326 Posted Apr 4th 2008 2:16PM]

Epic fail.....

[KAL326 Posted Apr 4th 2008 2:17PM]

Originally @betamax

Engadget comment system also = epic fail...

[(Unverified) Posted Apr 4th 2008 2:54PM]

epic fail? you do know that means it failed so much that it's come full circle and is funny? I'd just say fail.

Sory 2 b a douche

[(Unverified) Posted Apr 8th 2008 12:47AM]

The 5D and 7D ARE NOT FILM CAMERAS. They are DSLRs just like the Alphas.

[(Unverified) Posted Apr 5th 2008 1:22PM]

I've also made a modification of the same lens earlier, and posted a guide for anyone to modify this or another similar old lens to the mount of their choice (doesn't need to be Sony/Minolta AF) starting from the photo at: http://www.flickr.com/photos/arkku/1266938702/

The advantage of my modding method is that it doesn't require any custom-machined parts parts; a non-electric conversion costs about $5-10 for an expendable M42 adapter (plus the lens itself, obviously), adding electronics for IS/etc obviously depends on obtaining a proper microchip for the camera (but for Sony DSLRs it's about $40 extra). The mod is also very easy to do, took me about 45 minutes initially, most of the time after that (can be hours) is spent adjusting the infinity focus position to desired accuracy.

Don't let old lenses go to waste, it's not hard to modify some of them to fit your current camera. Personally I've even converted a 1913 Vest Pocket Kodak camera to M42 system, which means that with an electronic adapter THAT retains IS and focus confirmation. I bet the makers of the camera didn't see that one coming. =)