M42->MAF Adapter With Focus Confirmation

If this can help, I've recently bought a multiple lens AF chip from James Lao to rechip a Sigma 1.6X AF Multiconverter for Nikon Ai lenses (but I use Tamron Adaptall-2 lenses with Nikon socket, so for me this is a Sony/Minolta Adaptall-2 1.6X AF Multiconverter).

The chip I've bought has an uncommon number of contacts, six instead the usual five or eight ones. Probably this is a new "James Lao" version of this AFC-L4B chip.

I've ordered it for a 1.6X Teleconverter, so focal lenght of the mounted lens have been increased by a 1.6X factor and brightness decreased of 1 f/stop ( plus sometimes +1/3 EV on camera body).

The Sigma Multiconverter now allows to use some Tamron Adaptall-2 lenses (90/2.8, 180/2.5 and 300/2.8) in S and P mode too, with AF.

I can use two zooms too (70-150/2.8 and 80-200/2.8), but focal lenght reported into EXIF is correct only for two / three FL and this has to been switched into adapter, making correct use of zooms a bit dificult.

I've choosen this values for the chip: 150/4,200/4,300/3.5 and 500/4:
you can divide FL by 1.6 to discover wich lenses I mount....

I think it may be possible to make a chip with two multiple-position switches to choose manually a FL and an f/# without work with camera buttons, but this requires a bit more effort to mount switches on adapters ( bluethooth or wi-fi technology may help, but one must write a smartphone app too....).

Bye.

Luca

TDMcManus2966 wrote: My question is: I want to buy a Minolta Maxxum/Sony Alpha mounted 400mm f5.6 Sigma tele lens( has 72mm dia. filter)that I am told fits Minolta 7000 but (not i) version Minolta film cameras. This Sigma lens is also listed in Safari Green color. The store, KEH in Atlanta, GA(USA) also is listing 3 other lenses ( same) but in diffeent conditions. I have been in Contack with KEH and sales person said this Safari/Green ( not i) can not be used on Minolta 7d or 5D camera. Does anyone know if the others (sigma 400mm f5.6 AF) that are Listed would fit my KM-5D? Will I need to have the chip replaced or re-chiped with a JamesLaoT chip?

Why not just get an AF 70-300mm lens such as these 2 types listed on evilBay: 271270442012 & 141051252037. I can't think you'll get any sort of quality of image with the 400mm you're referring to beyond 300mm anyway (have you checked user reviews on the Dyxum lens database). If you ever look for Tokina SD AF lenses, they look identical but have different coloured alignment spots. The pale blue one is for SLR, the yellowish and red are for digital (just in case you ever buy one), so always check images of the lens, and if you can't see the spot colour, ask the vendor and body-swerve the pale blue unless you're shooting with an A-Mount SLR. The Minolta 7000 is A-Mount the same as the Maxxum/Dynax/Alpha so will fit DSLR's, but you probably knew that anyway.

to Lesuave:

I've experienced some troubles in the past contacting James Lao.

If it cans help, I've ordered a custom chip on
http://eadpt.com/eadpen.htm
and payd it using PayPal ( like you, I suppose).
The PayPal address was:
reshg@sina.com
to:
Lixin Tian

I wrote directly to James Lao here:
james@jameslao.com

I've tried another E-mail too, this one:
tianlx@hotmail.com
.... but this last one seems to be inactive.

Don't worry about answering delays: I've experienced periods of two weeks without replies.... but the chip was then delivered and I'm happy with it.

Bye.

Velocina

Hi Lesuava,
As I remember, the address

reshg@sina.com

was good both for PayPal than to communicate with James Lao. I've had several contacts with him do decide the best data to put into a "four lens AF chip for rechipping" to put into a Sigma AF 1,6X Multiconverter.
The last time I wrote to James Lao was after received the chip, 2nd August 2013.

I've found somewere on Internet this additional info:


************************************************************************

James Lao
About &
Contact
email: james@jameslao.com U.S. citizen
phone: (503) 863-9219
home address: campus address:
2767 NE Roberts Ave. Carnegie Mellon University, SMC 2249
Gresham, OR 97030 5032 Forbes Ave.
Pittsburgh, PA 15289
I have strong programming, design, and problem solving skills. My interests include
distributed systems and robotics. I'm looking for a full-time position.
Education Carnegie Mellon Pittsburgh, PA
Bachelor of Science in Computer Science
 Expected graduation date: May 2012
 GPA: 3.60
Professional
Experience
Apple Inc. Cupertino, CA
Software Engineering Intern, iOS Location Summer 2011
Amazon.com Seattle, WA
Software Development Engineer Intern Summer 2010
My project involved developing scalable Java web services and a Ruby on Rails front-end.
After I nished my project, I helped develop and test the order fulllment software the
team was responsible for. I used agile development and TDD techniques.
Vernier Software & Technology Beaverton, OR
Programmer Summers 2007 { 2009
I worked on a wide variety of projects ranging from internal tools to customer-facing
websites and applications. Two examples of things I worked on are a solar panel data
collection/reporting web application and a part defect tracking tool.
Other
Experience
Open Source WordPress Development
 Category Posts Widget (150K downloads, featured in WordPress Top Plugins book)
 Simple Video Embedder (86K downloads)
Programming C, C++, Objective-C, Java, Scala, Ruby, Python, Standard ML, PHP, SQL, JavaScript,
HTML, CSS
Software Mac OS X, Linux, Windows, Eclipse, Vim, Emacs, Xcode, Git, SVN, Adobe CS
Awards Spring 2011 Dean's List
2007 Oregon Student Technologist of the Year
2007 & 2008 Oregon SkillsUSA Web Design Champion
Course Work Distributed Systems, Machine Learning, Probability Modeling, Game Theory, Computer
Graphics, Robotic Manipulation, Feedback and Controls, General Robotics

************************************************************************

The schedule was originally a .pdf document.

I've had no response on @hotmail by James Lao, but every time I wrote him on the others adresses I've waited for days an answer, but he answered me every time.

Bye.

Luca

Ok,
now we know that almost the PayPal address ( reshg@sina.com , please correct me if it isn't the right one ) is working.

Bye.

Luca ("velocina")

Good !
I've waited three weeks from Honk-Kong to Italy, but Italian Custom is the bottleneck.....
Only for statistics, the chip you've bought from James Lao is a single or four lens type ?
I've bought from him a four lens type with AF function enableb to rechip a rare Sigma 1.6X Multiconverter, that now makes some old manual lenses AF ones: the chip has 6 contacts, not five, nor eight: it is a bit strange....
How many contacts has your chip ?

This is mine AFC-L4B chip, which I've requested with 150f4, 200f4, 300f3.5 and 500f4 lenses programmed inside: I use the Sigma Multiconverter with three Adaptall-2 Tamron lenses: SP 90/2.8 Macro (#72B), SP 180/2.5 (#63B) and 300/2.8 (#360B) with good IQ on my A700:
the Multiconverter makes these lenses AF ones and the A700 adds stabilization too.

Thanks for the reply to my previous post: now I've to investigate which is the purpose of the sixth contact on the chip, probably a fixed voltage supply, indepenndent from the main switch on the camera, that is always connected to the positive lead of the battery: I suspect this because of the fact that the change of setup of my four lenses chip is done depressing the lens release button on the camera when the power on switch is in "OFF" position and the memory (CF and/or Memory stick )activity led is estinguished. In this condition the usual "+" supply pin to the lens (one of the basic five ones) is disconnected from battery, but the chip changes setup..... and this is very strange if the camera don't supplies it curent... From this the suspect of the purpose of the sixth pin on James Lao "programmable" adapters.
Your single lens one probably does not need this supplementar pin ( never changes setup, so processing without power supply isn't required), but make the same printed board for both chip kinds is simpler than two. Probably the two adapters differ themselves only in the firmware programmed into.

Bye.

Luca ("Velocina")