Flat Field Macro Lens
/forum/topic/1162649/0



Pete Klinger
Registered: Nov 22, 2006
Total Posts: 147
Country: United States

This probably seems like a contradiction, because more often, objects are 3D. I'm trying to get up close to pages and images, in books and make a full frame (with APS-C sensor) image of what would be an 1/8th page or 1/6th page ad.

The larger pages and full page aren't as much of a problem.

I need to get close and in focus, flat field and not distorted.

I tried my 100mm Macro, it's 14" away. Wondering if there's something shorter that someone can suggest that will focus closer, on a small portable copy stand. The 28-135 "macro" is also unsuitable and doesn't get close enough. Canon cameras.

Extension tubes? Close up adapters? Is there a 28mm flat field Macro lens?



LordV
Registered: Jan 02, 2006
Total Posts: 28183
Country: United Kingdom

Think the widest common lens I've seen is this Tokina AT X M35 Pro DX Macro lens.
Most macro lenses should have a flat field but not sure how good this one is.
Brian v.



e6filmuser
Registered: Oct 11, 2008
Total Posts: 1632
Country: United Kingdom

I don't understand why you think you need to get close.

In general, the longer the focal lens, the less distortion you will get. That is why portrait lenses are longer than standard. As you don't want much DOF you would be even better of with a moderate telephoto.

A potential problem is that modern consumer lenses have some distortion uncorrected in the knowledge that the camera will correct them. Such a lens would have to be used with a suitable camera.

My starting point wouild be a Tamron SP 90mm macro, which covers a field 10cm wide x 7.5cm high at a distance of about 50cm (m4/3 x2 crop factor).

Close working distance options:

The SP 17mm, with 7mm extension will cover 5cm wide with 5cm working distance. It is a rectilinear lens.

http://www.adaptall-2.org/lenses/51B.html

The Olympus OM 24mm 2.8, with 7mm extension, will cover about 4.5cm to 7 wide with 5 to 7cm working distance. It looks very sharp, with the meerest hint of barrel distortion at the very edges of the frame.

All of the above are manual focus film lenses.

I hope some of this helps.

Harold



aabbabc
Registered: Jan 05, 2009
Total Posts: 189
Country: China

These photo are taken by Tokina AT X M35 Pro DX



100% crop


100% crop right bottom corner


hope these help



Pete Klinger
Registered: Nov 22, 2006
Total Posts: 147
Country: United States

Thanks for the tips. Part of the reason for close, is the size of the copy stand arm. These are antique book illustrations, so absolutely flat, I don't need to worry about depth of field.

I have a 100mm Canon macro lens, but I'm not sure I can get back far enough. It's kind of "too good". 28-135 isn't the best for this either. Scanner picks up the texture of the paper.

This one was done with an S-90

Velociped

Time to look for the 35mm DX Tokina. I appreciate the advise.



Michael Gordon
Registered: Apr 07, 2007
Total Posts: 407
Country: United States

The Oly 50/3.5 macro is generally rather perfect for a copy stand as far as working distance, flat field, sharp corner to corner. The bokeh can be harsh but that doesn't matter in this situation. It is rather inexpensive. Again it is fully manual lens to be used on an adapter.



e6filmuser
Registered: Oct 11, 2008
Total Posts: 1632
Country: United Kingdom

Michael Gordon wrote:Again it is fully manual lens to be used on an adapter.
Fully manual on an adapter but auto diaphragm in the OM system.

Harold