SWC - what's the straight scoop?

Hasselblad has made something like four, maybe more, variations of the SWC.
The latest lens allegedly usees lesser glass to accommodate environmental
concerns. I'm just not sure.

So which, if any, SWC model has the T* coating that was made before they
switched to the environmentally friendly glass?

jjs wrote:

Hasselblad has made something like four, maybe more, variations of the
SWC.
The latest lens allegedly usees lesser glass to accommodate environmental
concerns. I'm just not sure.

It uses other (!) types of glass. In no way lesser.
The lens' performance is very much the same as that of the ones with the no
longer used glass.
There are slight differences in MTF between the old and new (going from
image center to corner), but it's hard, if not impossible, to tell which of
the two would be better than the other. The differences are really minimal,
and where the one is better in the center of the image than the other, the
other is better in the corners.

This near identical performance is amazing, since the initial design was
done using slide rules and note pads, the current redesign made use of
brute-force computer calculations.

So which, if any, SWC model has the T* coating that was made before they
switched to the environmentally friendly glass?

There is no connection between T* coating and new glasses.

T* coating was applied to all Biogons since 1973. At that time, the "SWC"
with black finish lens barrel was the current model.
Before that, all lenses had a single layer T coating.

The model with the redesigned Biogon is the current 905 SWC.

jjs wrote:

Hasselblad has made something like four, maybe more, variations of the
SWC.
The latest lens allegedly usees lesser glass to accommodate environmental
concerns. I'm just not sure.

It uses other (!) types of glass. In no way lesser.
The lens' performance is very much the same as that of the ones with the no
longer used glass.
There are slight differences in MTF between the old and new (going from
image center to corner), but it's hard, if not impossible, to tell which of
the two would be better than the other. The differences are really minimal,
and where the one is better in the center of the image than the other, the
other is better in the corners.

This near identical performance is amazing, since the initial design was
done using slide rules and note pads, the current redesign made use of
brute-force computer calculations.

So which, if any, SWC model has the T* coating that was made before they
switched to the environmentally friendly glass?

There is no connection between T* coating and new glasses.

T* coating was applied to all Biogons since 1973. At that time, the "SWC"
with black finish lens barrel was the current model.
Before that, all lenses had a single layer T coating.

The model with the redesigned Biogon is the current 905 SWC.

"Q.G. de Bakker" wrote:

The model with the redesigned Biogon is the current 905 SWC.

Has anyone done a head-to-head comparison (like this* one of the 80mm
lenses) of the Biogon and the Mamiya 43/4.5? The extra 13% image
magnification strikes me as a lot more attractive then the extra vertical,
although the extra vertical can be used for a bit of shift of a rectangular
crop.

Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)

*: http://www.hevanet.com/cperez/test/fourcameras.html

**: http://www.hevanet.com/cperez/MF_testing.html

David J. Littleboy
Tokyo, Japan

On Sat, 4 Dec 2004 22:33:56 +0900, "David J. Littleboy"
wrote:


Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)


Dave, did I just hear you say "Reala" and
"sharp" in the same sentence?


rafe b.
http://www.terrapinphoto.com

On Sat, 4 Dec 2004 22:33:56 +0900, "David J. Littleboy"
wrote:


Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)


Dave, did I just hear you say "Reala" and
"sharp" in the same sentence?


rafe b.
http://www.terrapinphoto.com

"rafe bustin" wrote:
"David J. Littleboy" wrote:

Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at
the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to
hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)


Dave, did I just hear you say "Reala" and
"sharp" in the same sentence?

Yes. I'm re-evaluating my films. Although it doesn't have the colors of
Provia/Velvia 100F, it looks quite good at 2800 dpi (downsampled from 4000
dpi). I think that with NeatImage and some aggressive sharpening it'll look
very good on a 9x print. That's 13x19 from 645, and I'm home free when I get
the PX-G5000.

But the Tessar ain't up to the job. Sigh. Bummer of the week.

David J. Littleboy
Tokyo, Japan

On Sat, 4 Dec 2004 23:36:17 +0900, "David J. Littleboy"
wrote:


"rafe bustin" wrote:
"David J. Littleboy" wrote:

Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at
the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to
hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)


Dave, did I just hear you say "Reala" and
"sharp" in the same sentence?

Yes. I'm re-evaluating my films. Although it doesn't have the colors of
Provia/Velvia 100F, it looks quite good at 2800 dpi (downsampled from 4000
dpi). I think that with NeatImage and some aggressive sharpening it'll look
very good on a 9x print. That's 13x19 from 645, and I'm home free when I get
the PX-G5000.


The only problem with Reala is the noise,
which shows up in the shadow detail of prints.
The sharpness is first-rate. NeatImage is a
nice tool.

PX-G5000 being presumably the 13" version of
your Epson R800?

I've been printing on an HP DesignJet 30 for
the last few weeks and getting to like it.
Who knew? It prints 13x19". Archival dye-ink
prints, if HP and Henry Wilhelm are to be
believed. Some very nice features, and "pro"
grade construction.

Tessar, Biogon, whatever. I've never taken
this stuff seriously but have noticed that
my Nikon 90mm LF lens is way sharp and is
refered to as a "biogon derivative." Hmmm.


rafe b.
http://www.terrapinphoto.com

On Sat, 4 Dec 2004 23:36:17 +0900, "David J. Littleboy"
wrote:


"rafe bustin" wrote:
"David J. Littleboy" wrote:

Chris's numbers** for the Mamiya 7's 50mm lens have a disturbing dip at
the
far edge at f/5.6 and f/8. (The stuff I do really requires the edges to
hang
in there. I just shot some Reala in my f/3.5 T* Tessar Rolleiflex, and
scanned at 4000 dpi the center is flipping amazing, but the edges and
corners are a disaster. Sigh.)


Dave, did I just hear you say "Reala" and
"sharp" in the same sentence?

Yes. I'm re-evaluating my films. Although it doesn't have the colors of
Provia/Velvia 100F, it looks quite good at 2800 dpi (downsampled from 4000
dpi). I think that with NeatImage and some aggressive sharpening it'll look
very good on a 9x print. That's 13x19 from 645, and I'm home free when I get
the PX-G5000.


The only problem with Reala is the noise,
which shows up in the shadow detail of prints.
The sharpness is first-rate. NeatImage is a
nice tool.

PX-G5000 being presumably the 13" version of
your Epson R800?

I've been printing on an HP DesignJet 30 for
the last few weeks and getting to like it.
Who knew? It prints 13x19". Archival dye-ink
prints, if HP and Henry Wilhelm are to be
believed. Some very nice features, and "pro"
grade construction.

Tessar, Biogon, whatever. I've never taken
this stuff seriously but have noticed that
my Nikon 90mm LF lens is way sharp and is
refered to as a "biogon derivative." Hmmm.


rafe b.
http://www.terrapinphoto.com

"rafe bustin" wrote:

The only problem with Reala is the noise,

Where does it come from in this particular case, Rafe? Does it have
something to do with a specific dye-layer in Reala? I've struggled with
Kodachrome 25 for such reasons.