On the wide end:
I would look at the Rodenstock 32mm and 28mm and 23mm. All the are excellent lenses, the 32mm being the newest. I have used the 23mm and have a 28mm. The 28mm is the best wide angle lens I have used on any medium format back. I found the 23mm too wide for me. I think overall the 32mm is the best solution, but it's cost with the CF is just too much for me. Rodenstock now calls the 28 and 23 the S and the 32 is in the W line.
Rodenstock makes a physical CF for all three of these lenses and I would consider it. The CF is 1K (yes) but I found it helped quite a bit on vignetting problems. Rodenstock puts a hard disk in these lenses that stops your shifting at about 7mm on the 28mm (you see the disk and ruins the shift). I have been told that the 32mm has the same disk but you have more room since it has a larger image circle. 70mm on the 28 and 23, 90mm on the 32.
Also consider the Schneider 28mm and 35mm. Guy wrote an excellent write up on the comparison between the Schneider 28 and Rodenstock 28 on this site. It's still up in the review area.
Rodenstock 35mm, great lens, smallish image circle of 70mm. Not a real good shifting lens IMO. No physical CF made by Rodenstock (I still feel it could use one). Hard disk stops horizontal shifting at 7mm. (huge issue for me). Nice size and tends to be very reasonably priced.
Schneider 35mm is an excellent all round lens, small package and @ F11 stunning clarity and contrast. I would recommend the physical CF for this the 35mm. The 35mm is reported not to be a good player for the IQ180, but it works find on the 160. You can get horizontal shifts of about 12mm before you start to lose saturation and see detail smearing.
Schneider 43mm is an excellent lens and a newer design that the 35mm as I understand it. I find that I tend to lead with the 43mm. It's contrast and clarity are excellent. You can shift it to 18mm horizontally before you see loss of details or saturation loss (again on a 160). I would recommend the physical CF for the 43mm. Very large image circle of 110mm
Rodenstock 40mm W Excellent from all reports, I have not used it
Schneider 60mm Digitar XL. My second most often used lens. Details are crips and contrast/clarity excellent. It's not as close to the 100mm you are using however. The 60mm has a huge image circle of 120mm. You can easily get horizontal shift of 25mm (I have taken it to 30mm) without loss of details/smearing. At 25mm you start to see loss of saturation. I use the physical CF on this lens mainly for shifting. On center the vignetting is very slight. Sharp as a tack.
Schneider 90mm Digitar. This lens comes by excellent reviews. I have not used one, opting instead for the older Rodenstock 105mm. This Rodenstock is in the older sironar-digital family. So far I like the 105 even though it's the older series of glass, in that it seems to work very well with the 160.
Note on backs. The 180 seems to be much less forgiving on these lens I guess due to the smaller pixels. People report bad results with the Schneider 35mm and 43mm, but great results with the Rodenstock 40mm and 32mm. I don't know about the 28mm. All of the lenses I have listed work great with the IQ160.
One other note, take a look here
Cambo Photographic Industry
Cambo has by far the best info pages on all of these lenses. Their website is a font on knowledge.
Paul
