Aperture/Depth_of_field Relationship -- Vivitar 85-205mm f3.8 Tele-Zoom

Aperture/Depth_of_field Relationship -- Vivitar 85-205mm f/3.8 Tele-Zoom

It got into my head to set my ancient Vivitar 85-205mm ƒ/3.8 Tele-Zoom lens up on a fixed scene, and take pictures at different aperture settings, to show the effect of aperture on the depth of field and image quality. I ended up doing it twice, with the lens zoomed all the way to 205mm, and again zoomed in to 85mm.

This is an ancient, non-AI lens built in the late 1960s or early 1970s. See also, this thread for a similar treatment of my equally-ancient 50mm ƒ/1.4 Nikkor.


[In case anyone is wondering, the text that is lost in the glare in both of the above pictures, just clockwise of the serial number and counterclockwise of the “Vivitar” name, is “AUTO”.]

Aside from depth of field, this lens has some rather interesting distortions that occur at wider aperture settings.

So, here are the results. Note that aperture setting, focal length, and other lens-specific characteristics are not correctly recorded in the EXIF data of the following images, due to the fact that this is not a CPU lens, and does not provide these data to the camera.

ƒ/3.8:


ƒ/5.6:


ƒ/8:


ƒ/11:


ƒ/16:


ƒ/22:

Wow, that's a cool lens. What was your distance to the subject?

That's pretty cool. Although the bokeh isn't like todays lens's for some reason. Look's somewhat different.

PapaST said:

Wow, that's a cool lens. What was your distance to the subject?

Click to expand...

I had intended to measure that distance before I took everything down, and forgot to do so. I can only now give a rough estimate that it was certainly at least six feet, and probably not more than ten feet, from my camera, to the Hershey's bar on which the lens was focused.

Bob Blaylock said:

It got into my head to set my ancient Vivitar 85-205mm ƒ3.8 Tele-Zoom lens up on a fixed scene, and take pictures at different aperture settings, to show the effect of aperture on the depth of field and image quality. I ended up doing it twice, with the lens zoomed all the way to 205mm, and again zoomed in to 85mm.

This is an ancient, non-AI lens built in the late 1960s or earlier 1970s.

View attachment 112837 View attachment 112838

Aside from depth of field, this lens has some rather interesting distortions that occur at wider aperture settings.

So, here are the results. Note that aperture setting, focal length, and other lens-specific characteristics are not correctly recorded in the EXIF data of the following images, due to the fact that this is not a CPU lens, and does not provide these data to the camera.

ƒ3.8:
View attachment 112808 View attachment 112809

ƒ5.6:
View attachment 112811 View attachment 112812

ƒ8:
View attachment 112813 View attachment 112814

ƒ11:
View attachment 112815 View attachment 112816

ƒ16:
View attachment 112817 View attachment 112818

ƒ22:
View attachment 112819 View attachment 112820

Click to expand...

After all that hard work I hope you got to eat the sweets

Philnz said:

After all that hard work I hope you got to eat the sweets

Click to expand...

Alas, no. I'm diabetic. What candy and sweets we keep around are for my wife. Or for me to use as photographic subjects.

Bob, Nice visual demo. Thanks for taking the time to do this.