Bronica RF 100mm lens test part 1

[sf]

This is not only a test of the 100mm's focusing accuracy wide open, but also a test of my B&W film developing skills. And of the accuracy of my RF to focus the unicorn 100mm 'long' lens.

The first image is of a grill thermometer shot at the closest possible distance to the lens (beyond the safety mark at 1.8 meters - closer to 1 meter). The lens, because Bronica believed the RF incapable of focusing the 100mm accuractely close up and wide open, has its last distance mark at 1.8 meters. All of the images in this test were taken at its physical stop at around 1 meter.

Each is shot wide open at F4.5. Arista.edu Ultra 200 (fomapan 200) developed in Arista Premium (Clayton F76+) at 1+9, 75 degrees F, for about 7.5 minutes. Scanned on the Multi Pro at 3200 DPI as a B&W negative.

The second image is a blow-up of the thermometer face itself, so you can see the accuracy of the focus more clearly.

Third image is a shot of some stone spheres game, wide open, 1.2 meters or so, same processing as above.

No Photoshopping has been done to these images. No sharpening, contrasting, curving, etc.

 

[sf]

Here are three images.

Crops of the spheres at F4.5, F8, and F32.

I notice the decreasing contrast from F/32 to F/4.5. But, the front sphere (in focus) is just about equally sharp in each shot. F/32 does little to degrade the image quality, at least as far as can be seen on this film given its grain.

All of these were shot at the closest focusing distance (roughly 1 meter).

 

[clarence]

Lovely lens. I like the smooth bokeh when it's wide open.

Just wondering, for the shot of the grill, did you physically measure the distance to be 1 meter as well?

Clarence

 

[sf]

Lovely lens. I like the smooth bokeh when it's wide open.

Just wondering, for the shot of the grill, did you physically measure the distance to be 1 meter as well?

Clarence

OH, no. No physical measuring. The lens' distance scale stops at 1.8 meters, and there is a large space after which it continues on down to what seems to be about a meter (perhaps even closer). A long arm's length. I just twisted it until it stopped, backed off a very slight amount, and focused. So, I'd guess it is at about 1 meter, give or take 10cm. Point is, it isn't 1.8 meters, not by a long shot, an yet it focuses 100% accurately, even wide open.

 

[clarence]

Very interesting. This means that with a bit of pre-visualisation for parallax compensation, you could take close-ups of heads for portraiture.

Clarence

 

[Art C.]

This is not only a test of the 100mm's focusing accuracy wide open, but also a test of my B&W film developing skills. And of the accuracy of my RF to focus the unicorn 100mm 'long' lens.

The first image is of a grill thermometer shot at the closest possible distance to the lens (beyond the safety mark at 1.8 meters - closer to 1 meter). The lens, because Bronica believed the RF incapable of focusing the 100mm accuractely close up and wide open, has its last distance mark at 1.8 meters. All of the images in this test were taken at its physical stop at around 1 meter.

Each is shot wide open at F4.5. Arista.edu Ultra 200 (fomapan 200) developed in Arista Premium (Clayton F76+) at 1+9, 75 degrees F, for about 7.5 minutes. Scanned on the Multi Pro at 3200 DPI as a B&W negative.

The second image is a blow-up of the thermometer face itself, so you can see the accuracy of the focus more clearly.

Third image is a shot of some stone spheres game, wide open, 1.2 meters or so, same processing as above.

No Photoshopping has been done to these images. No sharpening, contrasting, curving, etc.

Try Kodak Tri-X 400. Expose and Dev. @ 200 - Follow Times at Kodak web site. Excite your life with a #25 Red filter.

"a test of my B&W film developing skills" Your skills are in the Darkroom.

 

[sf]

Very interesting. This means that with a bit of pre-visualisation for parallax compensation, you could take close-ups of heads for portraiture.

Clarence

Not sure what you mean. . . about pre-visualization for parallax. The parallax correction of the RF continues beyond the distance scale markings, of course. . .all the way till the lens stops turning. Maybe I misunderstand you.

 

[sf]

Try Kodak Tri-X 400. Expose and Dev. @ 200 - Follow Times at Kodak web site. Excite your life with a #25 Red filter.

"a test of my B&W film developing skills" Your skills are in the Darkroom.

I have a red 25, using it for IR photography on the Maco IR film (Rollei 400 IR). I might try using it on some desert landscapes i intend to do this spring out in the Gorge in George area of Eastern Washington.

 

[clarence]

Not sure what you mean. . . about pre-visualization for parallax. The parallax correction of the RF continues beyond the distance scale markings, of course. . .all the way till the lens stops turning. Maybe I misunderstand you.

No, I hadn't known that the Bronica could do that even beyond 1.8m. That's wicked.

Clarence

 

[Dougg]

Clarence, I think Bronica just didn't want customers to count on perfect focusing performance/repeatability any closer than the 1.8m marking. Closer than that it's "try your luck" and there are warnings in the manual too. The focusing and parallax both work right on down to the stops, as George indicates.

I don't have any decent samples or tests wide open at closest focus to add to George's interesting test. Here are a couple of shots anyway, the first was wide open focused on the fence post at center, and the second is about closest focus but not wide open...

 

[sf]

Doug . . . . please tell me what film that is in the second image. It just looks so dense and grainless.. . .

My Multi Pro makes PanF look grainy - I'd love to know how you get that LF look from the negs. You have your stuff scanned at the lab, huh?

Maybe I need to start shooting my portraits in Velvia.

 

[Dougg]

Doug . . . . please tell me what film that is in the second image. It just looks so dense and grainless.. . .

My Multi Pro makes PanF look grainy - I'd love to know how you get that LF look from the negs. You have your stuff scanned at the lab, huh?

Yep. lab scan at the time of processing, 2692x2000 pixels. You know what film that is, George; it's Fuji NPZ 800 at EI 500.

 

[clarence]

Being able to use high speed film without the disadvantage of grain is one reason why I am so into medium format.

Clarence

 

[sf]

yeah, I know the film and the rating. . . I just can't believe it.

I'm about to post my second roll of home developed film ever. . . it's amazing. I have to give myself a standing ovation. Again, I had a timer, but it didn't work right, the temperature was a little warmer than I wanted, so I kind of winged the dev time again. . . and they are good. Very good. And with the 100mm, most of them.

 

[Dougg]

Good results are what counts... glad you're pleased. Looking forward to seeing some samples. Pan F?

 

[sf]

No. Shooting Arista.Edu Ultra 200 from now on . . . absolutely love the film. Beautiful grain and controllable grain too. I like it better than anything I've used with the only exception being Neopan 400. . . but this stuff is about half the cost.

 

[sf]

Here are three shots

all with the 100mm, I'm pretty sure. Looks like it. Only other lens I brought was the 45, and they sure are not from that.

First one is wide open - nice bokeh showing.

 

[Dougg]

I found another minimum focus shot with the 100mm, probably around f/8. Focus looks right on... Our cat Squeeks (sister of my avatar cat) basking in the sun.

 

[sf]

Two more

Two more

First one from the 100mm. Wide open.

Second from the 45mm, F16.


All of these are from the same roll.

Love the film . . .


I have a cat named squeak. She's 22 years old. Gray. Broken tail. Shaved in patches where her fur knots up. Tough as nails.

 

[RObert Budding]

I'm happy to see that you have a 100mm in your hands. I was a bit worried about leaving mine to you in my will - I don't want to be run down by a car or meet some other unfortunate end.

Great lense, isn't it?