Stemi-dv4 dilemma

Anyone using this Scope out there ???
And what Magnification OBJECTIVE LENS have U got mounted ???
I am using an 0.6x LENS which has an approximate 40 mm ( +1.5") Objective field and this is giving me some beans.
Never looked through a Microscope in my life. I am 62 years young and we never had access to Labs in our days !!! Don't use my spectacles whilst working on the Scope, though.
Maybe need to concentrate on centering the work more accurately ???
Tried a 0.3x Lens with an Objective field of 83.3 mm.
However, with the FULL WORKING DISTANCE now increased from the old 130 mm to 285 mm ( 11.5" ) this turns out a disaster !!!
Should we try the 0.4x Lens which has an Objective field of 62.5 mm and a FWD of 210 mm - which is also a bit over extended ???
Or are we working totally incorrectly by trying to achieve a slightly large full circular cut in one complete go on one half of a rectangular 75 x 50
( 3 x 2" ) practise plate ???
As a rookie, we fear that breaking this cut would kill the fluency of the lines and result in maybe a jagged irregular looking circle ???
It had been brought to our attention previously by a kind Gent that whilst cutting most times, one is indeed expected to go over the initial cut to rectify matters or improve on the original cut.
Would this hold true for circular cuts as well ???
Seems hardly likely from how other experienced pneumatic-using Engravers work ???
Would sincerely appreciate You respected "old hands" and "Gurus" out there throwing some light in our hour of darkness.
Thanks a stack in anticipation
and LORD BLESS
aRM

I use a stemi 2000 with a .63 objective lens. It is necessary to keep your work centered, by using a turntable or a positioning vise. I also have a .4 objective lens. I seem to like using it when I am cutting a n overall pattern because of the increased field of view. The incrased working distance is managable. and not uncomfortable. The depth of field also increases a great deal. The other thing that happens though is that when you increase the working distance a normal ring light isn't enough. I use a fiber optic ring light with ajustable intensity. This way you can increase the light accordingly. I bought the light from precisionworld on ebay. Its Chinese, but it's only 300 dollars. It works great and the light is white. I don't know if you can get 5 power eyepieces for that scope, or if that would help as well. Maybe someone here who is more schooled in optics could give us some insite.

It woulod be great if optics could be designed specificly for our application. I think that even if it is possible the market isn't big enough Chris

There are vario supplementary lenses (0.3x ...0.5x) available for the Stemi 2000 and the DV4. They can give you free working distance between 234 to 91 mm. Related to the Stemi 2000 you have a object field of 118 to 9.2 mm (in use with eyepiece "WPL 10x23/Br.foc.").
The biggest object field you can have with the DV4 is 83.3...12.5 mm.
(Here is a link to a .pdf file, 5.2 mb, you can read yourself)

ARM, i use the Stemi 2000 with a 0.63x and i know, what you mean. If the cut is longer than you can see, it is a bit strangely. But with some practice you'll manage it soon. Stop cutting before you can't see the line anymore, replace the piece under the scope and restart cutting one mm before. With some practice you don't see such "stops and gos".

Mario

Christian DeCamillis said:

I use a stemi 2000 with a .63 objective lens. It is necessary to keep your work centered, by using a turntable or a positioning vise. I also have a .4 objective lens. I seem to like using it when I am cutting a n overall pattern because of the increased field of view. The increased working distance is manageable. and not uncomfortable. The depth of field also increases a great deal. The other thing that happens though is that when you increase the working distance a normal ring light isn't enough. I use a fiber optic ring light with adjustable intensity. This way you can increase the light accordingly. I bought the light from precisionworld on ebay. Its Chinese, but it's only 300 dollars. It works great and the light is white. I don't know if you can get 5 power eyepieces for that scope, or if that would help as well. Maybe someone here who is more schooled in optics could give us some insight.

It would be great if optics could be designed specifically for our application. I think that even if it is possible the market isn't big enough Chris

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Christian De Camillis Esq
At the outset permit me to say that we are indeed honoured to have your input here which is not only enlightening, but directive.
Mario Sarto has correctly mentioned below that there is, what they call a "VARIO LENS", for both our Scopes. They have this in a 0.3X to a 0.5X variable Magnification. Although all the specifics are not mentioned for the STEMI DV4, we reckon their figures of FWD +- 118 mm and 51.3 mm for the Objective field would be about the same as for my Scope.
We have also confirmed their inventory of this today with our local suppliers. I delayed in responding to Your reply for this reason as we wanted to do our homework also. This VARIO LENS is rather expensive here but we reckon that it would ideally solve our dilemma.
One problem we encountered with the 0.3X Lens was the totally different height of work which we were not accustomed to at all. We have been practising seriously with the 0.6X now for the past few months only and have taught ourselves to work at a particular height. This new height was strange and put us off completely from the norm we learnt.
We reckon that the 0.5X Lens would be the answer to our problem.
Is there something that we ought to have thought about here ???
Your recommendations would be immensely appreciated.
Thanks in anticipation.
Kindest regards
aRM

Mario Sarto said:

There are vario supplementary lenses (0.3x ...0.5x) available for the Stemi 2000 and the DV4. They can give you free working distance between 234 to 91 mm. Related to the Stemi 2000 you have a object field of 118 to 9.2 mm (in use with eyepiece "WPL 10x23/Br.foc.").
The biggest object field you can have with the DV4 is 83.3...12.5 mm.
(Here is a link to a .pdf file, 5.2 mb, you can read yourself)

ARM, i use the Stemi 2000 with a 0.63x and i know, what you mean. If the cut is longer than you can see, it is a bit strangely. But with some practice you'll manage it soon. Stop cutting before you can't see the line anymore, replace the piece under the scope and restart cutting one mm before. With some practice you don't see such "stops and gos".

Mario

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Mario Sarto ESQ
It's re-assuring to know that someone else is also using about the same in Scopes.
Like I mentioned earlier to Maestro Chris, we have indeed sourced the VARIO LENS with our local supplier today, thanks and full acknowledgements due to You, Marvellous MARIO.
With a 0.5 magnification and an objective Field of view of 51.3 mm, I reckon this should suit us perfectly, albeit with a little extra expense. I concede that "with some practise" we would eventually be able to master the limitations of the 0.63X Lens. However, whilst practising during these few months, I have been just about at the end of my tether practically fighting both my Scope and Turntable to get a clearer picture and an even more neat, precise and continuous circular cut. You see MARIO, as someone so wisely stated previously, we Rookies can initially blame our tools. One is allowed this expediency. Resolve and remove the problems, then we should definitely have no excuse.
In addition, we will be failing in our efforts without acknowledging that we are indeed humbled receiving these profound insights from the likes of Maestro CHRIS and Your Good self.
This alone would be impetus enough for us to strive and achieve the best within one's ability.
May Your countenance remain radiant with smiles.
Kindest regards
aRM

I haven't used the vario lens, I'm sure it works great since it's a zeiss. The only problem I see with it ,is thatit extends quite a distance below a normal objectiv e lens, so it seems that to obtain the field of view you want you will still have a grater working distance, of what appears to be in pictures at least a couple inches. I hope that makes sense. Chris

Christian DeCamillis said:

I haven't used the vario lens, I'm sure it works great since it's a zeiss. The only problem I see with it ,is thatit extends quite a distance below a normal objectiv e lens, so it seems that to obtain the field of view you want you will still have a grater working distance, of what appears to be in pictures at least a couple inches. I hope that makes sense. Chris

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CHRISTIAN De CAMILLIS
We have the FWD and Objective Fields given for the 0.3X and 0.4X.
Unfortunately the figures for the 0.5X are not recorded.
We are waiting on our local suppliers to get that from Germany !!!
You have a 0.4X which works well with added lighting. We used the 0.3X and found the working distance too great.
We just wanted to confirm that the 0.5X would indeed be much better than all these, so we think.
As soon as we have the relevant data on the 0.5 magnification we will let U know as it would be interesting to note this for our applications.
Thanks a stack again for the response.
LORD BLESS
aRM

Remember though, that the working distance is measured from the bottom of the lens. This vario lens apperas to extend an 1,5 to 2 inches further than the .04 lens. This could mean that your working distance will be the same if not more than the .04, and you won't have as large a field of view. I just want to caution you on that because it is an expensive lens if they let you try it first then do so. As far as I know they don't make a fixed .05 for the zeiss. Chris

Christian DeCamillis said:

Remember though, that the working distance is measured from the bottom of the lens. This vario lens appears to extend an 1,5 to 2 inches further than the .04 lens. This could mean that your working distance will be the same if not more than the .04, and you won't have as large a field of view. I just want to caution you on that because it is an expensive lens if they let you try it first then do so. As far as I know they don't make a fixed .05 for the zeiss. Chris

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CHRIS
You are correct, they don't make a 0.5X for any of our models.
We are going to get only one shot at this and it has to be now or never.
The Lens will come especially from Germany and there definitely won't be a chance to try it out. The Suppliers would obviously just want us to keep it as it will be brought-in specifically for us as an ordered item.
Methinks the only way around this would be to acquire the correct and exact Dimensions and technical specs from them and then we can decide which lens we should get. I will first pursue this angle, even if I have to extort it from them, and revert to You with some better info so's we can make a final decision.
Thanks and take care
aRM

I called Zeiss this morning by phone and talked to Mr. Lau. He will send me more information about the vario system per e-mail. Waiting for it - if i get it, i'll post it here. Hope, that is o.k.
Mario

ps: ARM - my name is Italian

Mario Sarto said:

I called Zeiss this morning by phone and talked to Mr. Lau. He will send me more information about the vario system per e-mail. Waiting for it - if i get it, i'll post it here. Hope, that is o.k.
Mario

ps: ARM - my name is Italian

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MARIO
Mama Mia !!!
We got our lines all crossed.............apologies.
U must be related to that Maestro GIANFRANCO PEDERSOLLI ???
Don't worry, just kidding !!!
The fact is that Your Countrymen are indeed producing exquisite work in lots of fields.
We have also received some info from Zeiss which is totally contrary to our expectations, due to the Vari-Focal Lens.
The 0.5 magnification only permits a 90 mm FWD with an Objective Field of 12.5 mm !!!?
This is totally useless for our needs.
As Maestro Christopher had earlier warned me, he is absolutely correct in his intimations that the Vario would not give us the same output results as the standard lens, even at almost three times the Price.
The 0.4X which Maestro CHRIS uses, on the other hand, has a fifty percent better Objective Field with a simultaneous increase in the FWD to 211 mm. I don't know if I will be comfortable with this long drop and whether I will still be able to continue cutting just as well, as experience with the 0.3X Lens proved my total inability to cope with the increased depth.
Like U had originally so succinctly advised, I now think I ought to master working with the 0.63 Lens at its lowest magnification, which we had started out with, and maybe look at another Lens later on when we would have gained much more experience to cope with these different depths.
We do appreciate every bit of Your time and effort You have so selflessly accorded us in pursuing to resolve this problem of ours.
Do please post any info which You will receive here as we are sure our fellow Forumites would indeed also benefit from our discussions.
A gracious Thank You and
LORD BLESS
aRM

ps: ARM - my name is Italian [/QUOTE]
MARIO
What is that Quotation below Your name ???
That looks more like LATIN ???
We studied a bit some 47 Years ago !!!
It reads something..........and imperative ???
Do translate.
thanks
aRM

Here are the informations from Mr. Lau (Zeiss):
By default there are some serious differences between the Stemi 2000 and the DV4:
the zoom factor - DV4 has 4, the 2000 has 7.7
the magnification range - DV4 has 8x to 32x, the 2000 has 6.5x to 50x
the field-of-view number - DV4 has 20, the 2000 has 23

using the Stemi DV4 with the vario front lens system at max. 0.5x and min. 90 mm free working distance
field-of-view number 20 mm : (least zoom 0.8 x 0.5x) = maximum object field 50 mm
field-of-view number 20 mm : (biggest zoom 3.2 x 0.5x) = least object field 12.5 mm

using the Stemi DV4 with the vario front lens system at min. 0.3x and max. 233 mm free working distance
field-of-view number 20 mm : (least zoom 0.8 x 0.3x) = maximum object field 83.3 mm
field-of-view number 20 mm : (biggest zoom 3.2 x 0.3x) = least object field 20.8 mm

In addition to the vario lens 0.3x...0.5x Mr. Lau advise a cantilever-type or hinged arm stand (i don't know, if you already have one), without such a stand the vario lens makes not much sense.

And at last the vario lens has a diameter of 66 mm - that means, the Fluorescent Microscope Ring Light or the LED Microscope Ring Light wouldn't fit.

So when i look at this, i think, it would be better (and much cheaper) to buy the 0.4x or the 0.3x supplementary lens...
...if you need it

The quotation is only my personal philosophy of life. Literally translated: subordinate yourself and dominate
The transmitting meaning is, first i have to understand, to learn how things work and not till then i can try to do them. Of course this doesn't work all the time, but it helps a lot It is a little difficult to transfer it to English.

Regards, Mario.

I
MARIO SARTO
You have done a lot of good work and explained the working capacities of these optics perfectly.
Thank You for taking all this trouble on our behalf.
We do have an hinged-arm Boom stand which we eventually got from Amscope and a Flourescent Ringed light which we purchased locally. The light will be able to accommodate the extra width easily.
However, as U finally mention, the regular Lenses would be a much better choice, albeit they won't perfectly suit the occassion.
I would kindly ask You to ask Mr Lau once more why they can't or won't make us a 0.5 Magnification Lens with an FWD of 130 mm and an OBJECTIVE FIELD of 60 - 65 mm - specifically for us Engravers !!!

MARIO, some 20 - 25 years ago we got very interested in Silhoutte and Bench Rest shooting, which had its origins in the USA ( I am sure ) and was very popular there. Now all these Shooters used to take utmost precaution in ensuring that their Re-loaded ammo was the best with perfect Head space, concentricity etc their Rifle Actions, Barrels, Bedding etc also the finest; all to achieve the ultimate and finest groups - a ragged single hole 3-5 shot group.
Now the ripple effect from this demanding sportsmen was that the Rifle and ammo Manufacturers jacked-up and drastically improved their Products, so much so, that U could shoot exquisite Groups with an out-of-the-box American made rifle and Factory Ammo.
Without mentioning manufacturers names, I am sure that young Guys like HRH FEGAREX and SIR SCOTT PILKINGTON and many others will bail me out here.

The point I am trying to make here is, as Engravers, most of whom have to make sure that bread is on the table first, why do we have to condescendingly accept what the Scope manufacturers dole out Year after Year. There are indeed lots of us and if we start shouting now, clearly refuse to accept what's ordinarily mass produced, make our intentions well known to these producers, I am sure these Scope guys will definitely take note of our requirements and specific needs. It's just that we have to make ourselves heard. Give them a piece of our minds. Let them know what works and what irks us. They will have to take notice as the hue and cry is now public. Just threaten to write one small adverse publicity article in the press - they will want to sue for defamation, libel or whatever. But at the end of the day one CEO or MD will see the light and will want to know what all the fuss is about. Infact when U think about it now, there have been lots of top brass who have had their pet collections Engraved by one of us. A word or two to these Gents will produce even better results.
Like one wise man put it beautifully .........for evil to thrive it only takes a few good men to remain silent and do nothing about it..............or something thereabouts ???
As far as I see it, pardon the pun, this is now "THE SCOURGE OF THE SCOPE"
I paid top bucks to get the best equipment 'cos like the Man said..."U don't buy twice"..........and U gets what U paid. For the life of me I can't see myself fighting this thing for the rest of my days to produce a piece of eye-candy.
We are going to ask them to give us what we want, nicely at first.
As for U, my Friends, U are either with me or against Engravers.
Either way............LORD BLESS
aRM
PS : That is an apt philosophy here.

MARIO
Any chance of talking to Mr Lau about making the 0.5X lens with our specs ???
Do let us know what he think.
Thanks
aRM

CHRISTIAN de CAMILLIS ESQ
Would U regard FWD 130 mm and an objective Field of 60 - 65 mm as perfect for our purposes ???
Am busy hashing the manufacturers to come up with an answer for us.
Thanks
aRM

ARM said:

Any chance of talking to Mr Lau about making the 0.5X lens with our specs

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I have called Zeiss again this morning.
I am sorry, they do not plan to produce the 0.5x lens.
Regards, Mario.