180/2.8 ED Ais with Nikon 5T and 6T diopters

[pluton]

Out of curiosity spurred by Tristin, I attached  the Nikon 5T and 6T screw-in diopters to my 180/2.8 ED Ais.  Results are sharper with the 5T wide open, a bit dreamy with the 6T wide open.  Stopped down these combos are usable, IMO.  The flower shot is with the 6T at MinFD at f/5.6

[Erik Lund]

Looks like quite OK performance at f/16

[Bjørn Rørslett]

Sometimes performance with these close-up attachments improve if they are mounted in reverse. Always worth a try.

[Erik Lund]

The glass elements are cemented together so quite easy to flip in the filter-holder, it's just kept in place by a threaded ring

[Bjørn Rørslett]

I know that - it's more difficult to keep track of which unit has been flipped over in its retaining ring !! Labelling the filter box will not suffice as the close-up attachments are moved a round a lot by their very nature.

The above of course presumes one has several of each, however. My situation unfortunately.

I do agree that making these filter being reversed is a breeze. One just needs a thin and pointed tool to put into the groove of the retaining ring to get it moving.

[Erik Lund]

A 'lens spanner' is the word

Yes mark the filter-holder and elements on the side, for instance with 'Front ->'

[Bjørn Rørslett]

I always used a thin flat-blade screwdriver and a small hammer. A lens spanner is of course even better, but the retaining rings of my various Nikon close-up lenses (3T, 4T, 5T, 6T) have been easy to engage and remove.

[Akira]

I guess the simple reversing in the original ring might be dangerous sometimes?  The reversed diopter may hit the front element of the master lens...

[Erik Lund]

Life is often dangerous, even for lenses 

[Akira]

Life is often dangerous, even for lenses 

Yeah, sometimes even a protection filter causes damages to the front element.   

[Bjørn Rørslett]

Normally this problem would be eliminated simply because the curved surface, even when the optics are reversed, rarely protrude outside their massive filter holding ring. I cannot say this has occurred any time with my experiments so far, but of course one cannot rule the issue out completely. Have a look from the side before mounting the filter to see if anything protrudes and act accordingly.

Even less likely a problem if you use adapters to mount hte filter, reversed or not, as the adapter step ring in itself pushes the mounting point further off the lens front.

[pluton]

I would have tried it reversed, but lack a 62-62 ring on hand.  The field was amazingly flat in the normal orientation, based on the ruler shots that I did.

[Tristin]

Much appreciation Pluton!  Now I know i can safely move on from the 200mm f/4.

[Ramon Mena]

Hi Pluton,
Probably you need a ring coupler male to male 72mm to 72mm.
It costs around 7 USD. Please see ebay Item Number 321936135972.
Best regards,
Ramón

[pluton]

Hi Pluton,
Probably you need a ring coupler male to male 72mm to 72mm.
It costs around 7 USD. Please see ebay Item Number 321936135972.
Best regards,
Ramón

Ramon, Actually, in this case it'd be 62 to 62, to match the 62mm threads of the 5T/6T.  That would then be threaded onto the 72 to 62 step down ring on the 72mm-threaded 180/2.8.  Unless they make a 72 to 62 double male threaded ring. 
Problem is, the local shops want strangely large amounts of money for adapter rings.  Typically they want US$25 or US$30 for a ring that can be purchased from B&H in New York for US$8 or US$12.