Pickup SRA - starting from a 500x microscope

Dear Mr Graves
I really enjoyed reading your comments. Superb post. If SRA can cause such excitement, than surely all is well in this hobby that we love and enjoy.
Cheers

Thanks Grooves for the very informative post which I'm in total agreement with. I bought my USB Microscope after reading about the importance of SRA on AnalogPlanet and have been using this method since and always with better results.

Good Listening

Peter

I have worked more with my first pictures. As you can see, if I could copy them here, they are quite good, but not good enough to measure the SRA at a one degree level. My measures vary between 87 and 98 degrees, based on subjective ideas where to set the cross or measuring point, using various resolutions etc, trying to establish the angle of the stylus, the diamond itself. Establishing the record surface angle is easy. I am using Gimp, a good open source program that includes arc measurement, as well as the Cooling Tech software that came with the scope. I may be able to improve the photo quality, when I get the scope back, or I will have to buy something better. Distance and magnification are obviously keys to getting the best photos, and correct light plays a big role too. The pictures are embarassing - why is my cartridge so dirty.

Picture nr 3 at the top here:
http://forum.audiogon.com/cgi-bin/fr.pl?vevol&1337191142

I measured once more. With my SME V arm I am only able to raise the arm 2 mm or so from parallel. If it is higher, at the back, the rubber rim on the arm lift starts to engage the arm tube (even though it is at rest, not lifted), and there seems to be no way to adjust it down. This means I will have to use a shim under the cartridge, to simulate the arm going up, if needed. Since the whole idea with the SME V is structural integrity, no flexible connections, shims or whatever, I hesitate a bit. But if a good photo shows that the SRA is too low, I will have to reconsider. As it is, listening tests indicate that the pickup sounds best if the arm is raised as far as possible. Perhaps more is needed. Some owners (like M Fremer) had to raise their Lyra Atlas pickups more than I can.