Dialyte Blur: Apo-Nikkors, Apo-Artars, Apo-Ronars ?

**Arne Croell** · 15-Jun-2009, 11:03

Originally Posted by monkeymon

Why is that? Most of these proses lenses have normal iris and a slot for waterhouses stops. All i could think is that you get the perfect circle that way.. but then i saw a square waterhouse stop. What is the actuall benefit of something like a square aperture? I doubt they were designed for bokeh nuts to go nuts on square highlights.

Its for changing the shape of the dots in the halftone printing process - remember, these lenses were used in process cameras, among other things for making halftone printing plates from continuous tone originals.

**Dan Fromm** · 15-Jun-2009, 13:44

aduncanson wrote "I would be surprised if I were to become a much better photographer by "improving my French" so that I could fully understand the contributions of off-axis lens aberrations to bokeh."

Well, if you don't want to understand Petzval lenses' off-axis "swirly" bokum, fine. But if you do an explanation of defocus blur won't help you much.

**Ken Lee** · 19-Jun-2009, 14:10

I acquired a 240mm APO Nikkor, and it's off to Grimes for mounting on a Technika board. We'll see how it stacks up against the others when it returns.

**Drew Wiley** · 19-Jun-2009, 15:53

I'm interested in this because I have quite a variety of Apo-Nikkors, all with multiple
blade apertures. I use them for enlarging lenses and they're superb. Unfotunately
process lenses have relatively small maximum apertures so it's difficult to get shallow
depth of field. Not really a substitute for the old portrait lenses in this respect. But I
do have a 720 which might render a shallow enough field in certain cases if I find a suitable shutter or have Grimes install one.

**Ken Lee** · 19-Jun-2009, 16:32

According to this online depth of field calculator, the depth of field is pretty shallow with a 360 at f/9. You must want something really shallow.

Some may like to emphasize only a part of a subject's face, but others (myself included) prefer to keep the subject in focus, and let the background be blurred. Hence my interest in 210-250 mm lenses, which do so nicely for portraits on 4x5.

The 240 APO Nikkor is quite small.

**Diane Maher** · 19-Jun-2009, 17:46

I have an APO-Nikkor and was wondering about the Waterhouse stops included in the box. It looks to me like they are all the same diameter. I don't have this lens in a shutter, so how would I go about using it with the stops?

**Clarence Rhymer** · 19-Jun-2009, 17:55

Hello Diane,

As a wild guess, could it be that you have a set of filter holders?

Cheers,
Clarence

**Diane Maher** · 19-Jun-2009, 18:07

I just looked in the box and yes, there are what appear to be filter holders, though I didn't know that is what they were.

However, there is a separate set of what appears to be five Waterhouse stops, with a much smaller hole in them but the hole is the same size on all of them. I bought this box set off eBay a few years ago. It was described as a Japanese tea set (I think). The whole thing (lens, filter holders, and stops) along with the unfilled out warranty card are all in a velvet-lined wooden box with a Nikon label on the outside of the box. It's a 455 mm APO Nikkor f/9.

**Ernest Purdum** · 19-Jun-2009, 18:13

At least you have templates for making stops the sizes you need. Maybe, some of them could be enlarged to a needed size.

**Ken Lee** · 19-Jun-2009, 18:23

"I don't have this lens in a shutter, so how would I go about using it with the stops?"

For the price of having one lens mounted in a shutter, you can get a Sinar shutter, which will let you shoot barrel lenses. You can get a used Sinar P for less than the cost of a brand new field camera.