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New Hasselblad Special Edition!!!

jotloob

Subscriber Member
I think , there is still plenty of time , till the CFV II 50 c + 907x will be on delivery . For X1D II its about 13 weeks from now .

So a question comes up for me . Godfrey was talking about FOV rather than AOV .
For AOV we can find the expression : Equivalent to or corresponds to focal lenght of , or behaves like , compared to FF .
Can we find a number for FOV ? ? ?

The 38mm BIOGON on the SWC origin (film 56x56mm) behaves like a 21mm lens on a FF camera .
The 38mm BIOGON on the SWC with a CFV II 50 C (sensor 33x44mm) behaves like a 30mm on a FF camera .

And the XCD 21mm with the CFV II 50 c behaves like a 16,5mm lens on a FF camera . That is too wide for me .
And the XCD 30mm behaves like a 24mm on a FF Camera .

Please correct me if this is wrong (or wrong thinking) .
 

pegelli

Well-known member
Jürgen, I think you need to consider that the original SWC was square (56x56) and that FF is rectangular (24x36) and that the CVF II 50c is also rectangular but with a different aspect ratio (44x33)

So when you do an AOV (angle of view) comparison you need to decide if you do it on the long side, short side or diagonal (of the cropped/non-square) sensor.

Once you decide which dimension to take the conversion is simple: dimension smaller sensor/56 * 38 mm

Calculations FF:
for the long side of the FF format it would be 36/56 * 38 = 24,4 mm
for the short side of the FF format it would be 24/56 * 38 = 16,3 mm (this would be the equivalent when cropping the FF image square)
for the diagonal of the FF format it would be 43,3/79,2 8 38 = 20,8 mm

Calculations cropped MF sensor:
long side 44/56 * 38 = 29,9 mm
short side: 33/56 * 38 = 22,4 mm (this would be the equivalent when cropping the cropped MF image square)
diagonal: 55/79,2 * 38 = 26,4 mm
 

jotloob

Subscriber Member
Trying to understand . I was never good in such theory and I am sure , I will never be . :banghead:
 

Godfrey

Well-known member
...
So a question comes up for me . Godfrey was talking about FOV rather than AOV .
For AOV we can find the expression : Equivalent to or corresponds to focal lenght of , or behaves like , compared to FF .
Can we find a number for FOV ? ? ?

The 38mm BIOGON on the SWC origin (film 56x56mm) behaves like a 21mm lens on a FF camera .
The 38mm BIOGON on the SWC with a CFV II 50 C (sensor 33x44mm) behaves like a 30mm on a FF camera .

And the XCD 21mm with the CFV II 50 c behaves like a 16,5mm lens on a FF camera . That is too wide for me .
And the XCD 30mm behaves like a 24mm on a FF Camera .

Please correct me if this is wrong (or wrong thinking) .
"Behaves like" is a judgement call. I was not making judgement calls: I was comparing calculated angle of view (and resultant field of view) measurements.

  • When I say "angle of view" (AOV), I mean the linear dimension in degrees that the lens captures on one axis of a format.
  • When I say "field of view" (FOV), I mean the combined linear dimension in degrees that the lens captures in horizontal and vertical axes of a format—essentially "H AoV x V AoV == FoV".
  • When I compare AOV and FOV calculations, I compare formats with the same proportions.

The original Hasselblad SWC camera has the format 56x56mm on 120 film and uses a Zeiss Biogon 38mm f/4.5 lens. This nets the following data:

6x6 Format: horizontal = 56 mm, vertical = 56 mm, diagonal = 79.196 mm
f=38mm
H AoV=72.8°
V AoV=72.8°
D AoV=92.4°​

For the Leica SL, I used a Super-Elmar-R 15mm f/3.5 to achieve the FoV of the SWC. For the Leica CL, I'm using the Voigtländer HyperWide 10mm f/5.6 ASPH; for the Hasselblad 907x, I'll use the XCD 21mm f/4.

For comparison, I consider only the crop to the maximum square frame with the lenses I've chosen.

  • APS-C Format: horizontal = 16 mm, vertical = 16 mm, diagonal = 22.6274 mm
  • FF Format: horizontal = 24 mm, vertical = 24 mm, diagonal = 33.9411 mm
  • MFD-s Format: horizontal = 33 mm, vertical = 33 mm, diagonal = 46.669 mm

And I use the diagonal AoV to indicate the HxV FoV since the format proportion I'm considering is constant (square).

These definitions and assumptions lets me make a simple table to indicate field of view between the SWC and my Leica CL, Leica SL, and upcoming Hasselblad 907x + CVF50c II cameras with the lenses I've chosen.


All of the choices are slightly different from the Hasselblad SWC in FoV performance due to the differences in available lenses of a suitable nature. They all also differ in terms of the relative coupling of the FoV with depth of field (DoF) because of the differences in format size, the required focal lengths for the FoV, and the resulting differences in lens opening range available.

I hope that proves clear and concise. :D

G
 

dougpeterson

Workshop Member
"Behaves like" is a judgement call. I was not making judgement calls: I was comparing calculated angle of view (and resultant field of view) measurements.

  • When I say "angle of view" (AOV), I mean the linear dimension in degrees that the lens captures on one axis of a format.
  • When I say "field of view" (FOV), I mean the combined linear dimension in degrees that the lens captures in horizontal and vertical axes of a format—essentially "H AoV x V AoV == FoV".
  • When I compare AOV and FOV calculations, I compare formats with the same proportions.

The original Hasselblad SWC camera has the format 56x56mm on 120 film and uses a Zeiss Biogon 38mm f/4.5 lens. This nets the following data:

6x6 Format: horizontal = 56 mm, vertical = 56 mm, diagonal = 79.196 mm
f=38mm
H AoV=72.8°
V AoV=72.8°
D AoV=92.4°​

For the Leica SL, I used a Super-Elmar-R 15mm f/3.5 to achieve the FoV of the SWC. For the Leica CL, I'm using the Voigtländer HyperWide 10mm f/5.6 ASPH; for the Hasselblad 907x, I'll use the XCD 21mm f/4.

For comparison, I consider only the crop to the maximum square frame with the lenses I've chosen.

  • APS-C Format: horizontal = 16 mm, vertical = 16 mm, diagonal = 22.6274 mm
  • FF Format: horizontal = 24 mm, vertical = 24 mm, diagonal = 33.9411 mm
  • MFD-s Format: horizontal = 33 mm, vertical = 33 mm, diagonal = 46.669 mm

And I use the diagonal AoV to indicate the HxV FoV since the format proportion I'm considering is constant (square).

These definitions and assumptions lets me make a simple table to indicate field of view between the SWC and my Leica CL, Leica SL, and upcoming Hasselblad 907x + CVF50c II cameras with the lenses I've chosen.


All of the choices are slightly different from the Hasselblad SWC in FoV performance due to the differences in available lenses of a suitable nature. They all also differ in terms of the relative coupling of the FoV with depth of field (DoF) because of the differences in format size, the required focal lengths for the FoV, and the resulting differences in lens opening range available.

I hope that proves clear and concise. :D

G


For lens equivalency I prefer a visual tool rather than doing the math longhand. It's especially helpful when talking about comparing different aspect ratios where "same diagonal" and "same width" or "same height" can be quite different.

Lens Visualization Tools By Digital Transitions

Of course, I'm biased, as I was the lead programmer :).
 

MGrayson

Subscriber and Workshop Member
For lens equivalency I prefer a visual tool rather than doing the math longhand. It's especially helpful when talking about comparing different aspect ratios where "same diagonal" and "same width" or "same height" can be quite different.

Lens Visualization Tools By Digital Transitions

Of course, I'm biased, as I was the lead programmer :).
It is a fine tool, but for comparing square formats, the numbers are enough. I'm happy to see that a 16mm on FF gives a square crop diagonal FoV about 1 degree wider than the SWC - good enough. And you have built in 4 mm shift on either side! :grin:

Matt
 

jotloob

Subscriber Member
I think , that I have to do some homework now . Thanks for everybodies comment about this . :thumbs:
 

Godfrey

Well-known member
For lens equivalency I prefer a visual tool rather than doing the math longhand. It's especially helpful when talking about comparing different aspect ratios where "same diagonal" and "same width" or "same height" can be quite different.

Lens Visualization Tools By Digital Transitions

Of course, I'm biased, as I was the lead programmer :).
Nice tool, but I see no way to simulate what a 10mm focal length on a 16x16mm sensor area would look like, or a 15mm on 24x24, or a 21mm on 33x33. It's fine for showing what a given focal length on some established camera or standard format looks like.

I prefer to work with the numbers and make my own visualizations with a graphics tool (a spreadsheet will do). I use Rui Salgueiro's field-of-view calculator to generate the numeric data, and I used Numbers on macOS to generate the previous FoV illustration I posted as well as this one ...


... which graphically makes clear the difference in field of view between the Leica CL+10mm, Leica SL+15mm, Hasselblad 907x+21mm, and Hasselblad SWC with Biogon 38mm lenses.

But then my degree work was in Mathematics and I spent more than thirty years in the science and technology industries, so I'm very very familiar with numbers and can visualize what they mean in my head pretty easily most of the time. :D

G

post: Oh yes, the camera that made the photograph was the Leica CL fitted with the Voigtländer 10mm lens. It was positioned not more than 7-8 feet from my head in this photograph, but I didn't measure the distance precisely.
 

jotloob

Subscriber Member
Godfrey

Thanks for your posts . That brings a lot of light into the darkness around FOV and AOV for me .:thumbs::thumbs::thumbs:
 

Shashin

Well-known member
When I was living in Japan at around the turn of the century, Japanese manufacturers always gave angular field of view in their lens specs (a very old tradition). That great thing about that was, regardless of the format, you could understand the angle of view. Then, when the new century came, digital started to take off and the 35mm photographers were getting confused. Camera companies invented the crop factor to help and then things went to hell in a hand basket.

If you can intellectually understand what an abstract number like focal length means in terms of angle of view, why can't you understand the actual angular measure?

:lecture:

/rant

:cool:
 
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Godfrey

Well-known member
None of these cameras have shipped yet, so it's no concern that there hasn't been much activity on this thread for a while.

I talked to my dealer the other day ... added a spare battery, the remote release, and the XCD 21mm lens to my order. I've also requested pricing for the optical viewfinder (accessory) mount and the grip shown in a couple of Hasselblad promo photos. Same battery as the X1D II, and I think the same wired remote as well.

I've also got a pair of lens adapters (for Leica M and R) on the way now. This will be fun.

My funding for the system is all in place, just waiting out until delivery at this point. And I still have a lot of gear to shift ... :thumbup:

G
 

rayyen

Member
I’m waiting for 907 too. I do landscape most of my time, so my 4116 serves me very well with all XCD lenses, recently I used a few times with xcd 135 & adaptor. But my favorite are 120, 90, 45 & 21.

I order 907 because I miss the old days of using my 500 & old v lens for portrait. I love the mechanic, waist level viewfinder, and the picture quality, I hope the CFV2 will not disappoint me.
 
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