Sharpest lenses for 0.3x...1.2x??

[ray_parkhurst]

Within the same PDF catalogue you can find handy lists for choosing the best lens for a certain usage, as they list the minimum pixel sizes of sensors that the lenses are matching, enlarging factor and image circle. See page 36 and 37.

Cool list. This was exactly the sort of info I was hoping for when I started this thread: info on lines of lenses that offer high quality alternatives for macro around 1x and that may have been more "modernized" than the ones I'd been seeing. Thanks to all for sharing this.

It also seems with this info I've come full circle versus my very first post on the forum, which was to ask for help in adapting the 95mm Printing-Nikkor I had just purchased. The mounting solution I finally found was the Rodenstock Modular Focus unit, which has adapters for various mounts but the base mount is M45x0.75, the same as the Printing-Nikkors. I see in the Linos literature that their Inspec 60mm and 100mm lenses also have the M45.0.75 mount and they recommend the MF unit to mount them!! It turns out that the 95mm and 105mm Printing-Nikkors were used in a number of industrial inspection applications, so the M45x0.75 mount may have been a standard developed for inspection lenses. A couple of the Tominon E36 lenses I've purchased came with various adapters from their M39 mount to M45 as well, so they may have been used in the same applications. All very cool stuff...

Ray

[Peter De Smidt]

Has anyone tried something like this: http://www.ebay.com/itm/EDMUND-OPTICS-N ... 336e7307a6 ?

[ray_parkhurst]

Has anyone tried something like this: http://www.ebay.com/itm/EDMUND-OPTICS-N ... 336e7307a6 ?

Looks like the image circle is a bit too small, only made for 2/3" sensors...Ray

[Yann E.]

I remember having "hot-spot" issues with a Tamron SP 90/2.5; reason being the rear element was flat so light was bouncing back from the sensor to lens and back againg to the sensor. When closing the aperture you would see a blue spot but at wide apertures you would just notice a loss in contrast
Regards
Javier

As for the later Tamron SP 90/2.8 model several years back already at the website of Tamron they had written information that for digital use they specially had changed the coatings of the rear lens elements to avoid hot spot problems (as good as it gets). It was their designation to "Di" naming in lenses, that it was optimized for digital usage. How good (or bad) lenses are in practice is asking to experience of many users.

Having owned and used both lenses extensively in the field, I'd say the hot spot was actually a rare occurence with the 2.5/90 under natural light, unless there was a highly reflective element in the picture and close to the optical axis. It was a bit more frequent with flash.
I never experienced any hot spot with the 2.8/90 DI, be it under natural light or with flash, with or without highlights in the optical axis.
BUT considering the 2 lenses have a totally different construction & optical layout, it is difficult to tell wether the improvement comes from the coating or the completely different design...

[ChrisLilley]

BUT considering the 2 lenses have a totally different construction & optical layout, it is difficult to tell wether the improvement comes from the coating or the completely different design...

I suspect the design at least as much as the coatings.

Tamron 52B 90mm f/2.5 is 8 elements in 6 groups; the last element seems to have an almost flat surface. (Manual focus, magnification 0.5x, has aperture ring).



Tamron SP AF 90mm f/2.8 Di is 10 elements in 9 groups with a convex face towards the sensor. (Autofocus, mag 1.0x, no aperture ring).

[seta666]

BUT considering the 2 lenses have a totally different construction & optical layout, it is difficult to tell wether the improvement comes from the coating or the completely different design...

I suspect the design at least as much as the coatings.

Tamron 52B 90mm f/2.5 is 8 elements in 6 groups; the last element seems to have an almost flat surface. (Manual focus, magnification 0.5x, has aperture ring).



Tamron SP AF 90mm f/2.8 Di is 10 elements in 9 groups with a convex face towards the sensor. (Autofocus, mag 1.0x, no aperture ring).

You can see in the drawins the 90/2.5 has a flat rear ellement; you won't see any digital lenses with a flat rear ellement as it is the cause of light bouncing back into the sensor. Problem was more eviden with high contras scenes and with small apertures; that was the reason I sold it

[Peter De Smidt]

Anyone have experience with Mitutoyo Compact Objectives, such as: http://www.edmundoptics.com/products/di ... uctid=2482?

[enricosavazzi]

But as for this Coastal Optics 60mm f/4 UV-VIS-IR lens, under certain conditions dependent for subject and lighting of the subject / background there can be a "hot spot" problem at a certain used magnifying factor. (Ghost image in a shape of the aperture in the middle of the image).
(...)

I am resurrecting this old thread to mention that I found a solution to the hotspot in the CoastalOpt 60 mm. It does not involve using an extension ring as suggested by CoastalOpt:

http://savazzi.freehostia.com/photograp ... tspot.html

And my review of this lens:

http://savazzi.freehostia.com/photograp ... pt_60.html

[ray_parkhurst]

I am resurrecting this old thread to mention that I found a solution to the hotspot in the CoastalOpt 60 mm. It does not involve using an extension ring as suggested by CoastalOpt:

http://savazzi.freehostia.com/photograp ... tspot.html

And my review of this lens:

http://savazzi.freehostia.com/photograp ... pt_60.html

Nice and logical solution and odd that it was not suggested by the manufacturer. Love the review and applications info on this lens, thanks for posting...Ray

[jjphoto]

I am resurrecting this old thread to mention that I found a solution to the hotspot in the CoastalOpt 60 mm. It does not involve using an extension ring as suggested by CoastalOpt:

http://savazzi.freehostia.com/photograp ... tspot.html

And my review of this lens:

http://savazzi.freehostia.com/photograp ... pt_60.html

Nice and logical solution and odd that it was not suggested by the manufacturer. Love the review and applications info on this lens, thanks for posting...Ray

+1, although it doesn't cure or fix the actual problem, it just minimises the symptom. I did the same (ie used a very effective lens hood) about a year ago on an enlarging lens I use but which shows a pronounced hot spot, or flare spot.

[Chris S.]

Enrico,

Thanks for the pointer to your review of the CoastalOpt lens. Even though I'm not in the market for this lens, it was fascinating to learn so much more about it.

Cheers,

--Chris

[kds315*]

Is there any news on this as I am actually looking for this macro range for shiny objects (cut gemstones) and jewelry (shiny metal).

I would guess this calls for an APO lens to avoid blue/magenta CA effects.

Appreciate feedback.

[Blame]

For 1:1 and down it would be difficult to do better than the Sigma 70/2.8 macro. The only reason the it wasn't an option is that the original poster wanted more access for lighting than such a short focal length lens provides.

[kds315*]

That's not apochromatic from what I know, so CA will get visible ...

[Blame]

Well the sigma does have some CA but it ain't bad or uncorrectable. Point is it is reasonably cheap (I just sold one for £200) and it is at least a contender for sharpest camera lens ever.