Yvar Macro 150mm f3.3 Question

[Don H Marks]

I feel like an idiot here, as I'm a long time Bolex user. Since the early 1980s. 

I recently got a Yvar Macro 150mm f3.3. 

The question is how to get to the macro setting of the Yvar. For example, I can loosen the focus stop screw, get into the macro zone and re-tighten the screw. That works fine, but is a little odd. 

Is there some trick I'm missing. Some hidden button or something. Or did they really expect people to loosen that focus stop screw to change the focus zones. I can't find an on-line PDF of the lens user's manual. 

Thanks in advance!

 

Yes it is an H8 REX and yes it is the H8 RX lens with the 2.2mm extended mount. Focus is fine. This picture was just a quick focusing test. I plan on using the lens in the middle position with a turret plug in the bottom hole. 

 

[Dom Jaeger]

I think the stop should allow a double rotation of the focus ring, to get into the macro range. Perhaps the mechanism has been incorrectly adjusted or something. It uses a small steel ball as an intermediate between the stop and the stop screw.

[Don H Marks]

Thanks Dom, I was hoping you might chime in. 

I do know that my smaller Macro Switars use the little ball that allows the two revolutions, I have seen that mechanism during CLA of the lenses.

However, close investigation of MY Yvar 150 reveals only an inner stop.  I can peek through the hole and can see inside and it appears there is nothing in there except the inner stop. Which is a slotted screw (that seems to function like an eccentric to fine tune the infinity stop). I see no additional mechanism to allow it to pass over this stop to the second revolution. It is pretty empty in there. 

I'm well familiar with e-bay purchases, so my first impression is someone buggered my lens. 

Before I dig into this otherwise pristine lens looking for signs of tamper, I ran across this curious description of a "dual-range" extension. Why call it that if it is one continuous seamless focus?

 

 

 

 

Edited March 7 by Don H Marks

[Don H Marks]

A little bit more research and I see every other lens has the stop screw flush with the body. My lens, the stop screw goes in exactly one full revolution from flush before it stops. 

So, If I back the screw out to flush with the body, yes, then it will do two revolutions, but won't stop at either end. 

This speaks to something buggered inside. Looks like I'll have to take it apart and see. 

Edited March 7 by Don H Marks

[Don H Marks]

The front of the lens has never been apart as the lens rings are pristine with no evidence of them ever having been removed. 

At the other end, the helicoid has been apart before, there are some scratched alignment marks present. No evidence I can detect of any mechanism to allow it to ignore the infinity stop to allow the second revolution of the focus ring to get into the macro range. 

Either an incompetent repair damaged the focus stop mechanism or a clever repair fixed a damage lens so at least it has perfect function from infinity to 12 feet.

No chance of getting a second lens to compare as this one was already low priced. I'll just leave it as is for now and consider it a slightly crippled lens that otherwise works fine. 

 

Edited March 7 by Don H Marks

[Don H Marks]

Pictures of the focus mechanism. I don't see any way to let the focus ring to two revolutions. Maybe some parts have been swapped with a non-Macro Yvar 150mm?

 

Edited March 8 by Don H Marks

[Don H Marks]

[Don H Marks]

With no solution immediately available, I put it back together. For now I'll just use it as is. I'll just loosen the screw if I need macro. It is in very nice condition. At the price I paid, it is too good to send back for a refund. 

Edited March 8 by Don H Marks

[Dom Jaeger]

The way the double rotation stop works is that the stop screw should be short enough to pass over the fixed stop pin, but not the steel ball in that groove. So the stop screw hits the ball, which does another rotation until it hits the pin.

If someone lost the ball, they may have fitted a longer stop screw, not understanding the mechanism. 

[Don H Marks]

Ok,  you have me feeling ever stupider. I should have seen that. I think I was put off by the fact the ball in my Macro Switars is so tiny. 

I have plenty of little ball bearings in my workshop at home. I should be able to get this fixed today. Thank you for your help!!

As I recall the little ball in the Macro Switar comes out through the hole in the lens, so the solution here could be as simple as popping a ball bearing in the hole without having to disassemble the lens again. 

Edited March 8 by Don H Marks

[Don H Marks]

After some experimentation with different size ball bearings, it appears a 2mm ball is what is needed. 

I was a little confusing at first because the lens as I got it was stopping in the middle of the infinity symbol (see images below). So, initially I was trying to get a ball bearing with a diameter to allow it to stop there. However, this lens the infinity is the line to the left of the symbol, a line which i mistook for the 200m line. But the 200m line is over one. A 2mm ball allows it to stop at the last line, which is indeed the infinity line. 

Anyway, the lens now works perfect!

 

Edited March 9 by Don H Marks

[Don H Marks]

Obtaining some ball bearings of various sizes...

[Don H Marks]

The 2mm ball was just the right size. 

[Don H Marks]

This is the lens as I got it. Looked OK to me at first, but infinity is really the line above the 200m. 

[Don H Marks]

Here it is with the proper 2mm ball bearing in place.  Now, of course, it will seamlessly go into the macro range as it should. 

[Don H Marks]

Amazing simple mechanism to allow two revolutions of the focus ring. 

 

Edited March 9 by Don H Marks

[Dom Jaeger]

Glad to hear you got it working. It is indeed a clever and simple mechanism.

[Patrick M P Donnelly]

Just to let members know: there is a clever and cheap series of cs adapters available for very little $$$ on eBay.

A 'CS adapter' is usually 5mm deep and is 25M or 25mm diameter, and enables c mounts to be used on cs cameras, usually for machine vision purposes. The less usual ones are 10, 15 and 20mm long.

Using one will bring objects closer to the sensor and enable greater magnification. Infinity focus will be lost.

[Simon Wyss]

14 minutes ago, Patrick M P Donnelly said:

A 'CS adapter' is usually 5mm deep and is 25M or 25mm diameter, and enables c mounts to be used on cs cameras, usually for machine vision purposes.

CS is the abbreviation of C mount, short. It’s not 25 mm but the imperial measure one inch diameter, 32 turns per inch pitch, 60 degrees flank angle thread. Or UN 1"-32, generally class 2. There are cameras that carry the Bell & Howell A, B or C mount.

We speak of the length of an adapter or a thread.

An inch is 25,400 mm.