I’ve been a photographer since high school, and an electrical engineer all of my professional life. The two things came together for a while. From 1989 until the middle of 1995, I worked as an IBM Fellow at the Almaden Research Laboratory south of San Jose, CA. My principal area of research for those six years was color management, color processing for digital photography, and color transformations such as gamut mapping. At other times in my career, I did research on speech recognition and speech bandwidth compression, and developed data acquisition and process control computer systems, telephone switching systems, and data communication systems.
There is a list of papers I’ve written and patents I hold related to color here.
I retired in 2000, and for the last 22 years when I’m not serving on NFP boards unrelated to photography, I’ve been spending most of my free time making photographs. I did serve for three years as the President of the Board of Trustees of the Center for Photographic Art in Carmel, CA, but since January of 2012 I’ve been back to trying to make art.
Hi Jim,
I did quite a few tests on the A7R vs the D3 last night. If you’d like to review the 200mm zoom tests I’d like any feedback you might have. Scroll to the bottom. I tried to keep the conclusions brief.
http://beforethecoffee.com/sony-a7r-vibration-comparison-with-nikon-d3-and-sony-nex-7/
I have been in touch with Sony. My link along with a message was supposedly forwarded to the Sony engineers. They replied to my email that they received it and they cannot say if or when a firmware update will be available.
I suppose every little bit helps.
Ferrell
Looks good to me. OBTW, I thought you were taking an unnecessary step when you delayed the strobe trigger in your earlier work. Looks like I was wrong.
Jim
Jim,
Being a new Sony A7R II user, I’m a huge fan of your most informative blog. Was curious however if you have cleaned your sensor yet. Do you do it yourself or have someone else do it?
The reason I ask is I’ve read that using a wet solution like Eclipse that works on every other sensor is harmful to the coating on the Sony sensor. Is this true? Also, how do you get around the sensor moving when using a sensor swab? I’ve cleaned close to a thousand sensors (part of my job), and yet I’m afraid to clean my own sensor!
Help!
Many thanks,
Michael
Michael, Sorry I can’t help you. I’ve never cleaned the sensors on my a7RIIs, or even the ones on my a7IIs.
Jim
I’ve cleaned sensors on a few brands – Olympus, Nikon, Leica, and Sony. The sensor on the A7 II is definitely coated with something that gives a slippery surface. I used a sensor gel stick to pickup any tiny debris off the sensor that did not come off with a bulb blower. Since the A7 II has IBIS, be gentle cleaning it. Where did you read that Eclipse is bad for the Sony sensor?
I don’t even know what Eclipse is. I don’t believe I ever said anything about its effect on a sensor.
Jim
Dear Jim,
Once again, I want to thank you for sharing your knowledge on here, as well as answering questions in the Nikon Z forum on DPR.
Photography is my hobby, and music technology has been my career and passion.
I read that you did research in speech recognition. I was wondering if you ever experimented or heard about using FM synthesis to create speech? I dabbled with this technique in 1985 when I found out my Yamaha MSX computer could “talk” using 4 “operators”, and then again when Yamaha introduced a synth called the FS1R- it used 16 operators- 8 voiced and 8 unvoiced which they called formant synthesis. I even found software that could take a .wav file and convert it to a FM patch and load it into the FS1R. The thing that made this a novel achievement is that it then became a “pitched” sound that could be raised and lowered without the speed of the word or words being changed unlike what happens when a .wav file is triggered above or below it’s original pitch. Just curious if you were into that kind of thing 🙂 Best Regards, Steve
Thanks. I never worked with that, but my MSEE thesis at the U of Illinois was titled “Speech Synthesis by Digital Computer Simulation of the Human Vocal Tract.” After that, I worked on a speech bandwidth compression scheme that took sort of the opposite approach: we analyzed the cochlear excitations produced by speech and sent descriptors of that excitation to the receiving end, where sounds that would evoke similar cochlear responses could be generated. The formant synthesis technique was different. If I remember right, that was the basis of the vocoder.
Hello Jim,
I see a lot of your comments on dpreview and I would like to take a minute to say “thank you”. You have a lot of expertise and it shows and I find pretty cool that you educate all of us on a daily basic.
My photography skills are at an enthusiast amateur level but every time I see your little avatar, I take the time to read the post and learn something new.
Thanks again,
Eric
I don’t know if you’re aware of this or not, but it sure looks like an interesting solution for the long-exposure-at-base-ISO nighttime photography: https://www.qhyccd.com/index.php?m=content&c=index&a=show&catid=94&id=55
And at $5k, it’s not priced ridiculously higher than a bog-standard A7RIV, either!
Wow! How do you suppose they get 51000 e- FWC out of that chip? I put the FWC of the a7RIV at about 37000 e-.
Judging from the first look at the blog, when I came across an article with test results of EFCS on Sony A7R3 I see a high-quality consumer use research material – appreciate it.
I’m surprised you didn’t put your full name here, specifically. May I ask why? You seem to be a wise fellow, most probably immensely technically knowledgeable, so I’m wondering – maybe I’m to learn something here about structuring the contents and communication of my own blog in the future.
Check out the site home page.
Got it! The changed text body (top bar, footer) with consistent font between the home page and subpages got the better of me.
That still doesn’t explain the lack of a full name in the section that’s very title asks for it. Plus, given search engine indexing and linking a number of visitors may not bother to navigate to the home page. Or they do and end up with the same result as me – I saw the text but didn’t notice the changed content since the style, and the position remained consistent.
I now noticed there seems to be a two-prong structure here, with the site and blog somehow intertwined, which surely added to my confusion and limited the chance of spotting the name mentioned at the site (not the blog) home page.