50mm Nikkor Unable To Focus

[brianmichel]

So I recently bought a Omega D5 Dichro with an assortment of carriers and lenses. The other two lenses I got focus without an issue, they are 135mm and 150mm respectively, the third lens is a 50mm Nikkor that can't seem to focus on a flat lens board. I seem to get a rectangle with rounded boarders no matter what I try. I've inspected the lens for any type of hazing, but it looks clear as a bell.

Could this be a function of using the improper lens board? Does it need a special extended board due to it's shortness? I really don't know where to start with this one.

Let me know what you guys think!

 

[Bob-D659]

Odds are you need a recessed lens board to get the lens close enough to the negative. The backside of the lens will need to be around an inch or so from the negative with the head up any distance.

 

[brianmichel]

That's what I was thinking, something to do with the lens board, I'll try to locate one unless you can recommend anyone selling them.

 

[Dave Swinnard]

Does this particular Omega have adjustable bellows? My D5 does. In order to use the shorter lenses you need to release the bellows using the black lever just back of where the lens board mounts and then push up on the bellow to reduce it's draw. Each time I change lenses from the 150mm to the 50mm I have to collapse the bellows significantly in order to get focus.

All my lens boards are flat ones.

Dave

 

[brianmichel]

Does this particular Omega have adjustable bellows? My D5 does. In order to use the shorter lenses you need to release the bellows using the black lever just back of where the lens board mounts and then push up on the bellow to reduce it's draw. Each time I change lenses from the 150mm to the 50mm I have to collapse the bellows significantly in order to get focus.

All my lens boards are flat ones.

Dave

My D5 does have an adjustable bellows, I'll have to go ahead and give that a try, thanks for the tip!

 

[brianmichel]

Dave, I went ahead and pushed up my bellows on the enlarger, time to make some giant prints it worked like a charm!