</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Aggie @ May 14 2003, 10:42 AM)</td></tr><tr><td id='QUOTE'>its the 105mm. What size enlargements does it do? I was hoping to do all sizes with it. This summer I am concentrating on 16x20's</td></tr></table><span class='postcolor'>
The data I have at hand is for Rodenstock Enlarging lenses. According to them, the 105 Rodagon (I would not expect the Schneider Componar to be much different) is *designed* for a field of 6cm x 9cm - or more coherently, a circular area with a diameter of 10.8cm. A 4" x 5" (or, if you are in Jolly Old, 5" x 4") negative would have a diagonal of 15cm... So I would not expect it to "cover" - at least not without fall-out and optical "badness" at the extremes (read: corners).
135mm and 150mm are designed with a 9cm x 12cm (4" x 5", or .. see previous ... ) field as a criteria ... so I *would* expect them to be appropriate. There is another choice - the Rodenstock "WA" lenses (I would guess that "WA" stands for Wide Angle - and I'm sure that Schneider and Nikon have equivalent wide angle enlarging lenses) where their 120mm f/5.6 Rodenstock WA is recommended for 4" x 5" ... The shorter focal length translates to a larger image at shorter column heights.
The easel on my Omega D5500 measures something slightly over 16" x 20" - with a 6cm x 6cm negative, I'm close to the top limit of the column, using an 80mm Rodenstock Rodagon, at this magnification. With the "regular" Rodagon, I can expect an enlargemt of 20" x 20" to fall within the lens design criteria. If I was to use a 60mm RodagonWA (also recommended for 6cm x 6cm) in its place, I could expect a limit of 30" x 30" - at a "something similar" column height.
I hope this helps - at least a little. It is difficult to be more specific without the data sheets for each individual lens. By massaging the information through some - really rather simple formulae - I could be more specific...
Uh ... but .... I think you would do well to consult Schneider or Rodenstock, or Nikon or ... whoever... rather than to trust these rather worn fingers on these keys.