Lense for Enlarger

Iam sure this question has been asked before, but I haven't found that thread. I have a Omega/LPL 4550XLG, variable contrast head. I have been printing without much sucess, 35mm negatives. I have recently gone to medium format. I currently use a Schneider 50mm lense, my first question is can I use this lenses for medium format and if not what size should I use? My negative size is 6x4.5. :confused:

I guess technically you could use that lens- if you don't expect sharp corners.

For that format, you should probably get a 75mm lens or a bit longer if you plan on shooting above 645.

Thank you, for your answer, and your quick response. I will look into getting a larger lense, thanks again...

There's an 80mm Minolta CE Rokkor enlarging lens in the APUG classifieds, snatch it if it's not already taken! Those lenses are worth every penny.

A 75mm or 80mm is typical for 6x4.5 or 6x6
A 50 may not cover that size without vignetting. Even if it doesn't vignette, the magnification would be pretty high and you may not be able to print smaller than 8x10

The general rule of thumb is to use an enlarging lens with the same focal length as a "normal" lens for the film format you're using. Thus, the specific recommendations others have given. Using a longer lens requires you to raise the enlarger's head higher than would be required with the "right" lens to make a print of a given size, and the print might be slightly less sharp than if you used the "right" lens (but that's very dependent on the specific lenses). Using a shorter lens requires the head be positioned lower for a print of a given size and is likely to result in vignetting and loss of resolution in the corners.