Member postings for Sam Stones

Yep, virgin on the ridiculous Dick H,

I beg to differ with regards to the changes resulting from the heat treatment of steel.

A higher tensile strength yes, but the modulus stays virtually the same.

And clearly, a four thou (0.1mm) thickness will even more approach a knife edge suspension while a six thou (0.15mm) thickness will be about 3.4 times stiffer than a four thou (0.1mm) spring. Similarly, the thinner the spring the less energy it will store.

Aren't we now talking about the method of suspension or am I now out of my depth?

Regards,

Sam (aka Dennis)

During my morning walk, I realised that I forgot to add that - doubling the distance between the two clamped ends of the suspension spring makes it eight times less stiff.

I bow to Russell's knowledge because I have no experience with this mechanism.

I wonder however, if the spring was 20 thou 0.5mm thick, would it still work?

I wouldn't know, but my guess is that it wouldn't.

Regards,

Sam

Hi Jim C,

My experience with clocks is quite limited, but applying basic bending theory, an eight thou suspension spring is 2.37 times stiffer than a six thou suspension spring.

Maybe that has something to do with it?

Regards,

Sam

Hi Steve,

Sounds like 'Plumber's radio' to me (wave guides and cavities?).

Climb milling; slow feed; plenty of turps.

Regards,

Sam

This unexpected revival has indicated that either I didn't know how to include pictures with text, or it/they were removed. Then again I was new to the forum.

Here are the missing images.

Regards,

Sam

Hi Jonathan,

I'd be concerned about the chemical resistance of PC.

Some chemicals (stress-crack agents) could ruin your PC and your day.

Take a look here -

https://en.wikipedia.org/wiki/Polycarbonate#Properties_and_processing

Regards,

Sam

I couldn't agree more Roy.

Whenever I watch Chris's videos, I feel like pulling my clock apart and doing everything properly just like he does.

The weather is superb at the moment Norman. Thanks for your good wishes and pleased that your son is enjoying his time down here.

Regards to all,

Sam

Gentlemen,

For anyone contemplating building a clock (or indeed wanting to produce quality parts for other projects), I highly recommend going to - **LINK**

Over the past almost two years, Chris has produced a remarkable series of short videos showing various stages of making a skeleton clock. His latest (bonus) video `Chill Out Edit - 1000 Hours in 12 Minutes’ is a `must watch’ summary of his previous high quality `footage’ amounting to 23 parts about clock making.

And, even if you are not interested in clock-making, Chris touches on many of the methods used in not only clock-making while bravely removing much of what would otherwise be time consuming footage.

Seasons Greetings to all from sunny Melbourne,

Sam (aka Dennis) Stones

Edited By Sam Stones on 15/12/2016 21:01:58

Yes Robbo, Very sobering.

Mind you, they've been at it for more than ten years. For a full blown account, go to http://www.my-time-machines.net/ where you'll find Mark Frank's incredible stories.

Sam

Hi Everyone,

If you have fifteen minutes to spare, watch this.

https://www.youtube.com/watch?v=lWd-HSOxCMM

Regards,

Sam (aka Dennis)

Edited By JasonB on 20/11/2016 20:53:27

Take a look at these!

http://www.dailymail.co.uk/news/article-3598540/The-Photographer-captures-pin-sharp-images-final-55-airworthy-Spitfires-using-just-handheld-camera.html

Gentlemen,

I've just been sent this link.

**LINK**

If you haven't had a chance to see this bloke's incredible efforts, then set aside an hour or more to watch.

Some of his techniques look crude, but wait until you see the results.

Truly breathtaking.

Sam

Lift the nose, then push!?

Thanks for all your input John.

Since there was a (2^nd page) thread glitch, I’ve only just found your latest and very absorbing post. Some of this is leaving me behind and I’m tending to lose sight of what I’d like – i.e. some good close up video without spending too much.

My earlier attempts to get close to the skeleton clock’s escapement was through the Sony 405 Handycam. It boasts a 60x magnification although that turns out to be a combination of optical (30x) and the rest digital zoom. See this single frame (Snapshot) image from the Handycam.

I feel sure that the Legria can be adapted to take better shots.

I’m pleased to note that (as you remark), it’s not very wise to hang a heavy lens onto the front of another, especially if the front end moves when focussing.

As it happens, the exposed section of the lens of the Legria HF G40 is quite rigid, and would probably support the weight in a nose-nose (lens reversal) arrangement. I still think it’s a good point to make for us with less knowledge.

Since I don’t (yet) have a 58mm male-male reversing ring, none of my test shots were taken with the lens fixed to the camera.

It doesn’t look as if I’m finished yet.

Thanks again,

Sam

Edited By Sam Stones on 06/08/2016 22:44:09

Thanks Michael,

I tried just briefly holding the lens as Howard mentioned, and it sure does bring things up close. But as you intimated, creating more working distance than one would expect.

I can hardly wait to get my hands on a 58mm Male-Male adaptor ring, if only to remove the slight hand tremor while I'm holding the lens in position and trying to keep the subject in focus.

I've learned even more from your `helical mechanism' statement.

When the lens is reversed it (the glass bits) remains stationary while the bayonet end moves in free air.

Another arrow in my quiver (perhaps that should be vibrato).

Regards,

Sam

Gentlemen,

What an interesting journey and who do I thank the most?

Anyway, thanks again to everyone for all your contributions, it's much appreciated.

Having already chosen to use both zoom lenses set at their extremes (see previous images), this morning I’ll be doing another couple of tests with the 100mm macro, placed to `rub noses’ with the Legria lens. Well not quite.

John suggests … in this case both lenses ideally need to be focused at infinity … which makes me think that setting both to shortest focal distance will be unnecessary. Probably worth a try while I’m at it.

In case I forgot to mention, the Canon Legria HF-G40 lens is fairly complex, but not intended to be removed. As for the sensor size, all I could find was 1/2.83-type CMOS 3.09Mp, which might mean something to those who understand.

Regards,

Sam

Thanks for that Howard.

My brief lash-up this morning (without a reversing ring), shows the effects of using two different zoom lenses. They were a 100-300mm and the standard (18-55mm) lens fitted to my stills camera. These were reversed and `snugged up to' the Legria. This camera was zoomed to full telephoto (equivalent to 73.4mm [35mm]).

With such minimal DoF it is extremely unlikely that I'll ever find a (video) use for all but the 300mm . I'm still in favour of a popping on a supplementary CU lens/filter.

An interesting journey so far, so thanks for your help and interest.

Sam

PS - I forgot to insert the composite picture and risk losing this note. I'll be back!!!

Oh! I almost forgot - the graduations are millimetres. 

Edited By Sam Stones on 04/08/2016 00:47:06

Here are my attempts using a standard lens back to back with the camcorder lens, as highlighted by Neil earlier.

The vignetting might come in useful when I'm feeling a bit arty.

Holding the lens against the camcorder by hand, leaves a lot to be desired from a camera-shake point of view.

Can't say the focus is all that brilliant either.

All this is looking good, so I might bite the bullet and get me a two-element diopter CU-lens/filter/achromatic/supplementary/...

No promises!

Regards,

Sam

Hi Neil,

It's heading for lunch time down here, and at last some sun is breaking through the clouds.

Both of your ideas make sense, although I hadn't thought of reversing a lens. It should be easy to test by holding another lens (back to front) in front of the camera.

Internet pictures of the North America and Pelican nebula show some spectacular colours. Good luck.

Gentlemen all,

I don’t know who to thank the most, so thanks to everyone.

There is certainly much (more) food for thought, and I now find myself in the awkward position (geographically) of `Try before you buy’. We are short of good camera shops close to where I live, and as yet, I’m not ready to splash out buying on line.

Here, however, is a bit of the background.

One of my many reasons for replacing a small Sony Handycam with this particular camcorder (a Canon Legria HF G40) was that my still camera is also a Canon (EOS 300D/Digital Rebel) and, like the camcorder, it too has a 58mm threaded lens.

With the still camera, I can get up close with either a Novoflex bellows and a choice of three lenses. Or I can simply jump in with a Canon 100mm macro, all of which have electronic coupling. With a couple of 58mm filters already in my camera kit (e.g. a circular polarising filter), it seemed like a good idea to aim for a little bit of compatibility. Unfortunately, that’s where the interaction and compatibility ends.

Unlike the still camera, the camcorder lens is not removable from the camera body hence why I’m looking at a screw in (58mm) supplementary (CU filter) lens. Just to complicate (or improve) matters, and besides a zoom range of x20, the camcorder has manual and auto focusing.

That aside, there is something rather odd about moving in close with the camcorder which I can’t get my head around. At full telephoto, the image will not come into sharp focus if the camera is any closer than 60cm to the subject. Conversely, at full wide angle the minimum focus distance is 10mm (1cm).

Regards,

Sam

Hey Neil,

I imagine that getting in close and personal with animate objects is a bit too risky at my age

I did capture the clock's escapement in slow motion (on a Sony Handycam). Slowed significantly via PowerDirector proved to be a big help to another clock enthusiast. Sadly, there won't be another clock out of my stables.

As for the CU lens/filter issue, I'm still trying to resolve the issue. Your comment about ` ... seeing the world through a pair of 3.5 diopter lenses ...' sent me scurrying for my best `readers'. However, the (rather crude) camcorder tests simply showed how bad my astigmatism really is.

I must thank every Forum member who contributed.

Good gear chaps!!!

I'll be back on this one shortly (or longly).

Regards,

Sam