ray_parkhurst
10-03-2015, 08:50 AM
There are a couple of 35mm macro lenses available that are useful for coin photography. Their main use is for higher magnifications, from 2:1 up to perhaps 6:1. Because they have adjustable apertures, they can do a good job for variety detail shots without focus stacking.
The lenses I own in this category were both sold with the Polaroid MP3 or MP4 macro photography system. This was a large format system, so image quality over a large coverage area was required. This is a very different requirement versus microscope objectives, which were really only required to be sharp at the centers where live viewing was done. It is actually rare to find a microscope objective that has wide coverage and flat field.
The lenses are:
- Rodenstock 35mm f4 Eurygon
- Tomioka 35mm f4 Tominon
The lenses are small, like enlarger lenses, but because they are macro lenses, they do not need to be mounted in reverse. The MP3/MP4 systems were intended for use with large format lenses, so are threaded M40 x 0.75mm to mount into Copal-0 shutters. This means they need an M40 to M42 adapter for use with common bellows.
I get about the same image quality from either of the lenses. At around 5:1 on APS-C, with f5.6, here are the images:
Eurygon
http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0014_A_A.jpg
Tominon
http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0016_A_A.jpg
The sharpness is obviously not as good as a focus-stacked image taken with an M5 or similar objective, but was simpler to take since this is a single image, no stacking required. For many folks this would be good enough, even for variety identification. This coin has a very minor split lower serif, and it shows well at this magnification.
The lenses I own in this category were both sold with the Polaroid MP3 or MP4 macro photography system. This was a large format system, so image quality over a large coverage area was required. This is a very different requirement versus microscope objectives, which were really only required to be sharp at the centers where live viewing was done. It is actually rare to find a microscope objective that has wide coverage and flat field.
The lenses are:
- Rodenstock 35mm f4 Eurygon
- Tomioka 35mm f4 Tominon
The lenses are small, like enlarger lenses, but because they are macro lenses, they do not need to be mounted in reverse. The MP3/MP4 systems were intended for use with large format lenses, so are threaded M40 x 0.75mm to mount into Copal-0 shutters. This means they need an M40 to M42 adapter for use with common bellows.
I get about the same image quality from either of the lenses. At around 5:1 on APS-C, with f5.6, here are the images:
Eurygon
http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0014_A_A.jpg
Tominon
http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0016_A_A.jpg
The sharpness is obviously not as good as a focus-stacked image taken with an M5 or similar objective, but was simpler to take since this is a single image, no stacking required. For many folks this would be good enough, even for variety identification. This coin has a very minor split lower serif, and it shows well at this magnification.