What lens is best at 2x and 3x?

[g4lab]

How about something new?

*** 1.6X stereo apo lens. ? ***

If someone want to try this I can furnish a brand new Zeiss PlanApo 1.6x Objective for the discontinued SV11 stereo scope. It would be $1,000 net of any paypal fees and shipping. A magnificent looking piece of glass. Thick and heavy. The last Zeiss Preiss on it was a hair under $3,000

[Joaquim F.]

To work on the field at 2-3X I use the Micro-Nikkor 60/2.8 AF D with extension rings, kenko AF and Nikon PN-11, closed between f4 and f8 nominal diaphragm is fine and auto diaphragm is very convenient for find and focus active insects.
In studio I prefer it than the EL-Nikkor 50/2.8 at that magnification range. I use a DX sensor camera, may be in FF is worse.
Is a very sharp lens but clearly have not Apo design, axial red-cyan CA can be quite visible
I'm not sure if is best in normal orientation with focus ring at 1:1 or reversed
at their "ideal" focus distances. I think is very close performance and normal position is far more practical.
Probably not the best but is a very nice lens, love it

Regards

Joaquim

[dmillard]

If anyone's feeling adventurous :

http://www.edmundoptics.com/onlinecatal ... uctid=3339

[enricosavazzi]

Between 1x and 2x (and actually up to 3x), I get excellent results with a Zeiss S-Planar 74 mm f/4, which is designed primarily for 1x magnification.

http://savazzi.freehostia.com/photograp ... ootout.htm

The Zeiss Luminar 63 mm f/4.5 (e.g. see at the same URL) is excellent in the 2x-3x (and above) magnification range. The Macro Nikkor 65 mm f/4.5 is quite usable from 3x, although better at higher magnification. The Macro Nikkor 12 cm f/6.3 is excellent in the 1.5-3x range, although it requires quite long bellows. The Micro-Nikkor 70 mm f/5 is also excellent (reversed) at 3x and above. Examples of test images are available on several pages on my web site. These lenses are perhaps not commonplace, and certainly not cheap, but all of them give top-notch results. Cheaper ones, like the El-Nikkor 68 mm f/3.5 and even the El Nikkor 63 mm f/2.8 and f/3.5 and the 50 mm f/2.8, are good to excellent when reversed, so I would say that there are quite a few very good alternatives in the 2x-3x range.

[ChrisR]

Enrico have you tried a good 2x microscope objective?
The working distance tends to be surprisingly small and the image circle wouldn't be big, but the central definition comparison would be interesting.

[enricosavazzi]

Enrico have you tried a good 2x microscope objective?
The working distance tends to be surprisingly small and the image circle wouldn't be big, but the central definition comparison would be interesting.

I tried one years ago, but the working distance was a problem (and at that time I did not use stacking).

I am sure IQ will be fine with a Mitutoyo Plan Apo 2x (plus tube lens), but at 2x and an NA of 0.055 the aperture is equivalent to f/9. Many of the lenses I mentioned earlier perform very well at similar apertures, and a microscope objective has no particular advantages over these lenses. The high NA of microscope objectives makes them superior to photomacrographic lenses (in terms of resolution) only starting from approximately 4x-5x.

[ChrisR]

I was thinking of something like this, occasionally on ebay (one currently):

Nikon CFI 2X Plan APO Objective, Nikon Part Number MRD00021.
Numerical aperture of 0.10 and a working distance of 8.5mm.

[Craig Gerard]

Chris,

That particular objective caught my attention also...for use with an APS-C; the pricing is prohibitive, but the NA of 0.10 is respectable....don't be anxious, I'm not in a position to purchase



Craig

[dmillard]

In the past, I also owned the 25, 40, and 63mm versions of the Zeiss Luminars, which I used on 35mm film and also on my 23 Technika. They worked well, but I sold them after moving to digital and discovering other alternatives (although I do have occasional regrets ).

I was thinking of something like this, occasionally on ebay (one currently):

Nikon CFI 2X Plan APO Objective, Nikon Part Number MRD00021.
Numerical aperture of 0.10 and a working distance of 8.5mm.

I saw that objective also, but that working distance looks a little short at that magnification, especially for such a large-barreled objective.

However, it inspired me to try my Mitutoyo Plan Apo 5/0.14 at 3X (7.87mm horizontal image field on my 23.6mm sensor), using a 120mm Apo Macro-Sironar as a tube lens (it was all I had on hand at that focal length). This combination gives an effective aperture of approximately 11, and a comfortable working distance of 34mm.

I took approximately 30 images at 25μm steps, stacked them in ZS PMax, and then gave the stack slight Levels adjustment and USM sharpening before posting.


Queen (Danaus gilippus) androconial patch at 3X, Mitutoyo M Plan Apo 5/0.14



Center crop (900x450 pixels)


Corner crop (900x450 pixels)

These are the crispest images I've produced at this magnification, although there may be higher resolution alternatives (like the objective described by Chris). I'm especially pleased with the performance of the Macro-Sironar as a tube lens, since it is optimized for 1/2 life size rather than infinity. (I also tried using a 105mm enlarger lens, to see if I could get an even lower magnification, but the corners vignetted slightly). I was going to run some comparative tests with a few other lenses I usually use at this scale, but that can wait until another day . . .

David

[Oskar O]

Thanks David, looks quite nice. I wouldn't be surprised that the Macro-Sironar works well, many symmetric close-up lenses work fairly well at a large distance when stopped down.

Now all that remains is a comparative evaluation of a few high quality objectives, close-up lenses with extension and stacked lenses

I started a stacked lens comparison for this magnification a few weeks ago, learned a lot and thinking of starting a new round of tests to narrow down on the results. It's just a ton of work to do...

[Blame]

dmillard

Nice pic. But did you take anything at 105mm? A bit of corner shading can be corrected in PP so it is still valid, and sometimes you just need a bit more room with full insect portraits.

[pierre]

Hello!


Have you tryed a sigma EF 180mm 2,8 APO
like this on ebay
http://cgi.ebay.de/Sigma-APO-Macro-2-8- ... RCH:DE:102

With a Raynox on it?