Post by Graham on Jul 1, 2018 12:57:49 GMT 12
As per the title, has anyone had success using a USB Microscope for stylus inspection ? There are numerous scopes on ebay and even Trade Me, some at bargain prices, but I am curious to know how good they are for this application. I imagine some super strong lighting would be required and even then I wonder if wear would be visible.
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Post by Owen Y on Jul 1, 2018 13:53:45 GMT 12
I am waiting for someone to identify a good one, without paying quite as much as what Fremer paid for his 😉 Most of them come integrated with LED lighting. However you may need to rig up a stand, if you want to inspect stylus in situ on the TT.
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Post by Citroen on Jul 1, 2018 18:03:12 GMT 12
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Post by Citroen on Jul 1, 2018 18:09:14 GMT 12
Not really convinced that these cheapies are worth it. The slightest movement and the pic goes totally out of focus, very fiddly and difficult to use.
You can tell if the stylus is clean or not. But as to the wear, I'm not that au fait with stylus profiles to recognise which edge is worn or not!
At sites I visit through work they have proper stereoscopic microscopes, which are far superior and easier to use. But of course these costs much more than these toys.
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Post by Owen Y on Jul 2, 2018 11:29:21 GMT 12
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Post by Graham on Jul 24, 2018 22:06:11 GMT 12
Well I went ahead and bought one that was on special at Aliexpress. I ordered the one that came with a vertical stand but found that the up and down movement was rather jerky so I carried out a mod that added to its stability. The little shoe at the bottom was from a dead ProJect tonearm rest. It just happened to be the exact radius
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Post by Graham on Jul 24, 2018 22:13:04 GMT 12
Below are some images using maximum magnification without using the zoom. This seemed to give the clearest images. My conclusion is that this is fine for general inspection but not good enough for evaluating stylus wear. This is also just using the built in ring of LED light. Maybe a better indication of wear might be possible with stronger illumination.
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Post by Owen Y on Jul 25, 2018 10:16:05 GMT 12
Images look reasonably OK to me - not real sharp but, with experience & playing with lighting & focus, they may be good enough to discern say wear-patches on a conical/spherical & elliptical stylii. Or wear-edges on line profiles. Magnif here is around 500x? Which product is this one?
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Post by Graham on Jul 25, 2018 10:54:27 GMT 12
IMO the performance is not too bad. As delivered it was very wobbly to try and focus but my little tweak has made this a lot smoother. I have also sprayed silicone onto the pillar which helped also. I've only fiddled around with it so far so some more practice may produce better results. The model is ACEHE ZC175700 which is available from numerous sellers with price ranging from $15.30 - $50 US. The claimed magnification is 50 - 500.
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Post by Graham on Jul 29, 2018 11:01:44 GMT 12
Here are a couple of shots of the Shibata stylus on my Excel pro 81. Interesting to just make out the stylus shape but I don't think its detailed enough to determine wear.
Not bad for a cheap Chinese toy !!!!
Same with maximum magnification.
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Post by Graham on Aug 7, 2018 17:06:59 GMT 12
USB Microscope Mk II
I found the supplied stand and adjustable mount a bit wobbly and jerky to focus so came up with a much better option. I remembered I had a cheap plastic microscope kicking around unused. It had rubbish optics but a nice solid steady adjustable mount. So I chopped off the optic bit and added a mount to take the USB microscope in its place. Works a treat
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Post by Owen Y on Aug 7, 2018 18:41:49 GMT 12
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Post by Owen Y on Aug 7, 2018 19:00:49 GMT 12
In the end I bought one of these on Tr Me: Next I need to get one of these: Or even one of these:
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Post by Graham on Aug 7, 2018 21:03:18 GMT 12
Lets hope you get better images than mine for all your trouble and expense !!
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Post by Owen Y on Aug 8, 2018 11:22:02 GMT 12
Hi Graham - old lab-quality microscopes come up for sale for not a lot - I paid ~$200 IIRC, as I was keen to get this one & other competitive bidding! However the value of these vintage scopes is readily recouped I think, unlike the low-grade stuff. The optics of course are top notch with a good brand. I'll try to get some digital images with just a hand-held point-n-shoot camera or cellph - without any stands or adapters or such.
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Post by Owen Y on Aug 8, 2018 12:30:18 GMT 12
Olympus ECE-Bi microscope (1960s)
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Post by michaelw on Aug 8, 2018 15:14:05 GMT 12
very nice ! with one of these a white labcoat would be the perfect attire. blutack cartridge support
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Post by Citroen on Aug 8, 2018 17:18:42 GMT 12
Brilliant.
I've tried lab microscopes in the past but could never get the stylus close enough. Never thought to angle it like that with blutak! Simply genius!
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Post by Owen Y on Aug 9, 2018 11:35:56 GMT 12
( Graham, sorry, hijacking your thread....) Yes, a microscope 'objective' lens needs to get real close & tends to bump into the cartridge body. Another disadvantage of an optical scope is the ultra-shallow depth-of-field, which makes it difficult to study a non-planar object like a stylus & its cut profile. I need to develop technique a bit, but an optical microscope works OK for studying a stylus. High magnification (say 400x) is very tricky to handle, as Citroen says, but lower magnif (eg 100x) is possibly OK if optical quality is good - I need to spend more time on this, jury still out. We're interested in the stylus tip, the groove contact 'patches' or edges, which might be only 0.035mm wide, only say 1/4 to 1/7 of the diamond shank width.
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Post by Owen Y on Aug 9, 2018 12:03:17 GMT 12
Some 'quick & dirty' images taken with a hand-held Canon S95 'point & shoot' digital camera, using some zoom, shot though the m'scope eyepiece, set at only 100x. The cartridge is an old Supex SM100E MM with Garrot Microscanner (line contact type) stylus fitted - not had a lot of use/wear, as I think you can see. (Quite a bit of resolution is lost through the camera, the through-microscope visual images are reasonably crisp.)
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Post by Owen Y on Aug 9, 2018 14:02:07 GMT 12
Lighting: I find that the best illumination is bright daylight. Or bright or hazy sunlight.
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Post by Citroen on Aug 9, 2018 17:23:22 GMT 12
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Post by Owen Y on Jun 30, 2019 12:19:41 GMT 12
Just for the record, I borrowed & played with a Digital Microscope with stand from an engineering design office. Results were no better than digital scope examples above. Built-in LED ring light with adjustable brightness, zoom to 200x, linear/angle/etc measurement.
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Post by Owen Y on Jun 30, 2019 12:50:53 GMT 12
Some image samples, of the same Supex SM100E/Garrott-Microscanner cartridge as in my Aug '18 posts above. As you can see, OK but not great (digital or optical) resolution - taken at 200x (magnif depends on display size). Image resolution is only 1.3M pixels here. Lighting is critical with m'scopes. You can benefit from messing around with lighting, to get the diamond facets lit. A cellphone flashlight can be used too. (The front plastic shroud on the m'scope is removed in order to get close enough.)
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Post by Owen Y on Jun 30, 2019 13:00:16 GMT 12
There are likely better digital m'scopes out there, but I am not impressed enough yet to buy one - at least one that is 'affordable' You can use them for VTA/SRA like Fremer suggests but, as you can see from Graham's Excel stylus above, there are diamond stylus cut profiles which are assymmetrical - ie. the line contact angle is not same as Stylus Rake Angle. (Re. VTA/SRA, I'd just trust the cartridge manufacturer & set up initially at least, for cartridge level with record & then use your ears to fine-tune.)
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