Hasselblad CFV ll 50c

[pegelli]

Don't worry.
A digital back or sensor cannot make anything less or more sharp than it is.

+1, fully agree

In my mind if you go to the same output size your pictures will be equally sharp or better than in the old film days.

The fact you might see small focussing errors and/or camera shake due to the higher sensor resolution at 100% magnification might be interesting, but I don't think it makes a difference (vs. film at the same output size).

But as is often the case "people suffer most from the suffering they fear", but YMMV.

 

[MGrayson]

WRT achieving focus with film vs. digital, there is an interesting theoretical issue. I say theoretical, because I've been unable to find the actual thickness of film emulsion (everybody tells you how thick the film is, but that includes the nonsensitive base as well).

Anyway, it is *possible* that a thick emulsion would be more tolerant of focusing errors. The interesting bit is the 3-dimensional plot of light intensity from a cone in a thick emulsion. Here is the result (angle of the cone greatly exaggerated for the purpose of illustration):

So while the exposed region in the film is larger because of the misfocus and thickness, the brightness near the true plane of focus is so much greater that the result looks *almost* perfectly focused anyway. The digital sensor would just record the large circle at the bottom of the cone.




I have no idea if this is a practical concern. I think our expectations of the two media differ, and that is more likely the issue.

Disclaimer: I am a big fan of both film and digital, and if the dust problem were manageable, I would use film a lot more. I enjoy processing B&W at home.

Matt

 

[TheDude]

The more I think about it, the more I think this was a really smart move on Hasselblad's part. I think the back (and probably the 907 as well) is going to sell like hotcakes.

I think so too. A IMX461 sensor version should therefore be just a question of time.

 

[Godfrey]

... I think our expectations of the two media differ, and that is more likely the issue.

Disclaimer: I am a big fan of both film and digital, and if the dust problem were manageable, I would use film a lot more. I enjoy processing B&W at home.

(bolded) I agree.

My expectations are not based on the media type but on what I want in the end product. I know a lot of folks shooting technical cameras and medium format digital are hunting for an edge in very large images. I'm looking for tonal differentiation and nuance in relatively modest sized prints ... that's my end product ... I only very very rarely print larger than a 13x19 inch, most of what I print is smaller than that. A square image area on an 11x14 print is more common for me, as well as other products much smaller than that.

I too still enjoy working with film, particularly B&W, and have no problem processing and scanning it myself. I don't have too many issues with dust, and whatever other defects are there I find to be part of the charm of working with film.

It might be that buying my long-hoped-for "digital SWC" ... CVF50c II (constrained to square) + 907x + XCD21mm ... and then having the back for occasional use on the 500CM and learning how to get what I want out of it might be the right approach. One thing I feel is certain: Having had the Leica SL and then finding the form factor not really to my liking after I retired and was no longer taking assignments, I'm less inclined to buy into the X1D and more inclined to like the traditional Hasselblad "box with a lens on the end" form factor of the SWC and 500CM with WLF. Yeah, it's weird. AND then there's the fact that the Leica CL + Voigtländer 10mm seems to be clicking nicely with me, and might obviate any need to spend more money on the H kit.

It's all good.

G

 

[pegelli]

I have no idea if this is a practical concern.

Interesting theory but my (also purely theoretical speculation) is that this is not a real concern for a few reasons

- The emulsion layer is very thin, film is (incl. base) about 0,2 mm, so I guess the emulsion is less than 10% of that, so say max 0,02 mm and your theory only works if the perfect plane of focus is somewhere in that 0,02 mm. With the inaccuracy of foucssing and the film never being perfectly flat I think that's a stretch

- I think one of the reasons films lose sharpness is by light scattering in the emulsion (it's not a completely transparent medium), so the more focussed "blob" in your first image will grow bigger and more diffuse due to this effect.

Sorry for this off-topic bla-bla, and I also agree with you (and others) that there's so many more differences between film and digital that I think it's almost meaningless to compare. Neither are perfect and both are entirely usable, just use what ever suits your final image.

For those interested, here's a nice reference on several effects what's happening when film gets hit by light and subsequently developed

 

[faberryman]

I hope you guys get your wish that the CFV II 50c is the same price as the X1D, but I have a hunch it will be more expensive. How price sensitive are you? Is there a price beyond which you'll pass?

 

[B L]

I hope you guys get your wish that the CFV II 50c is the same price as the X1D, but I have a hunch it will be more expensive. How price sensitive are you? Is there a price beyond which you'll pass?

It must be lower than a body including sensor. ie X1D.X1D2 or even FUJI 50 S or R.

 

[epforever]

You folks all make using a digital back sound like a royal PITA rather than the joy of having a nice bit of photographic equipment to extend the use of my existing setup into digital capture. That's very de-motivating to me.

...

I have never used microprism or split image focusing aids with my 500CM. I use the Acute Matte screen with grid and nothing else other than the WLF focusing magnifier or the higher-powered focusing chimney finder. And I have no problem focusing critically with it, given using an A12 film back or a Polaroid film back. I hope that this experience remains what I have when I try out the CFV50c II; it seemed to work fine with the CFV50c that I tested on the camera.

Given all the other equipment I already have, I'm not really in need of anything at all ... and I'm certainly not in a hurry.

Thanks!
G

Maybe I missed it, but another major factor people are neglecting to mention is this (forgive me if it's obvious): Using a cropped sensor -- i.e., 44x33, even 48x36 -- on a V body means what you're focusing on in the viewfinder is smaller than it would be when shooting 6x6 film. You have to back up or use a wider lens to get the same view you want. Picture a lovely portrait of someone in the 6x6 viewfinder, waist at the bottom of the frame, top of head at the top of the frame. To get that image with a 44x33 sensor, you need to position your subject much smaller in the Acute Matte screen. It makes a huge difference.

I loved using the old Aptus 54S (48x36 sensor) on my V system, but it wasn't always easy to nail focus. The lenses definitely have their own unique look.

 

[faberryman]

Maybe I missed it, but another major factor people are neglecting to mention is this (forgive me if it's obvious): Using a cropped sensor -- i.e., 44x33, even 48x36 -- on a V body means what you're focusing on in the viewfinder is smaller than it would be when shooting 6x6 film. You have to back up or use a wider lens to get the same view you want. Picture a lovely portrait of someone in the 6x6 viewfinder, waist at the bottom of the frame, top of head at the top of the frame. To get that image with a 44x33 sensor, you need to position your subject much smaller in the Acute Matte screen. It makes a huge difference.

How did they mask the viewfinder with the A16 back? Presumably Hasselblad will offer something similar for 44x33. A new AccuMatte screen with grids? Hate to be practical.

 

[leejo]

I hope you guys get your wish that the CFV II 50c is the same price as the X1D, but I have a hunch it will be more expensive. How price sensitive are you? Is there a price beyond which you'll pass?

The cost of an X1D II, or even the GFX 50R. Because why would I invest more into an EOL'd legacy system (the bodies and the lenses), with all the compromises of using this back on a V body, for the same or higher than the cost of the new system; when I could sell the legacy system and fund at least half of an X1D II or GFX 50R? Heck, the XV adaptor only costs $250, so this back is not really about using V lenses.

Hasselblad are marketing this as working with practically every V body ever made, so it's clear they're looking at a different target market to those users who would drop 5 figures on a digital back. They want to tempt those users who aren't using their V system professionally, or those who have one sat on their shelf for occasional use, or those who never sold it but never use it, or those who might think to pick up a second (third, fourth, whatever) hand body for use with the back. Capturing that market to pull them into the X system through the slim body attachment is a key strategy.

 

[jng]

How did they mask the viewfinder with the A16 back? Presumably Hasselblad will offer something similar for 44x33.

There was a translucent plastic mask one could slide in, in between the screen and focusing hood. And the outer lines of some of the gridded screens corresponded to the 645 and Superslide (A16S) format.

 

[siddhaarta]

How did they mask the viewfinder with the A16 back? Presumably Hasselblad will offer something similar for 44x33. A new AccuMatte screen with grids? Hate to be practical.

The crop indeed is quite heavy, especially for wide-angles a limitation.

Maybe they provide a screen as in the previous 50c back version.

 

[fotophil]

It appears that touch screen operations (perhaps even touch screen focus similar to the X1D) are one of the design goals for the new back. In the original back, Hasselblad did not attempt to iptimoize Live View Focus. As others have mentioned, it was a challenge. One of the problems that I experienced was the lack of control of screen brightness. Depending the ambient light and lens aperture, the Live View Image was often too bright (washed- out) ot to use for focus. I used a variable neutral density filter to adjust brightness of the screen image which was a great help because I could fine tune the screen to optimize shadow, midtone or highlight areas for critical focus. It will interesting to see how Hasselblad handles the Live View Function on the new back. The higher resolution LCD Screen and the tiling the screen to a horizontal position to permit the use of a hooded viewing device to block-out ambient light will help Live View Focusing. Hopefully there be some type of automatic screen brightness control. A $5700 price tag would be icing on the cake but I suspect it will be more. Perhaps there will be a bundle deal with the 907X Body? Has Hasselblad announced any schedule for delivery?

 

[TheDude]

In the original back, ... the Live View Image was often too bright (washed- out) ot to use for focus. I used a variable neutral density filter to adjust brightness of the screen image ... Hopefully there be some type of automatic screen brightness control

I also use a variable neutral density filter to adjust brightness of the screen image. Copal shutter is activated using the flash synch chord. Works well but is clunky and moving/changing images can be challenging. As quick (or slow) and fuzzy as sheet film.

An automatic screen brightness control in combination with an electronic shutter would make the Mark II much more user-friendly.

P.S. And please soon a Mark III with the back-illuminated 16bit, IMX411 sensor so that we can also forgo the color correction step at the exposure and post-exposure stage.

 

[tcdeveau]

P.S. And please soon a Mark III with the back-illuminated 16bit, IMX411 sensor so that we can also forgo the color correction step at the exposure and post-exposure stage.

Yes pretty please HB

 

[Shashin]

WRT achieving focus with film vs. digital, there is an interesting theoretical issue. I say theoretical, because I've been unable to find the actual thickness of film emulsion (everybody tells you how thick the film is, but that includes the nonsensitive base as well).

Anyway, it is *possible* that a thick emulsion would be more tolerant of focusing errors. The interesting bit is the 3-dimensional plot of light intensity from a cone in a thick emulsion. Here is the result (angle of the cone greatly exaggerated for the purpose of illustration):

So while the exposed region in the film is larger because of the misfocus and thickness, the brightness near the true plane of focus is so much greater that the result looks *almost* perfectly focused anyway. The digital sensor would just record the large circle at the bottom of the cone.




I have no idea if this is a practical concern. I think our expectations of the two media differ, and that is more likely the issue.

Disclaimer: I am a big fan of both film and digital, and if the dust problem were manageable, I would use film a lot more. I enjoy processing B&W at home.

Matt

Emulsion thickness was always a trade secret with film manufacturers. So the fact you cannot find a number is not surprising. However, having run a microscope lab, I attempted to answer this. This is color negative film with the emulsion to the bottom and the base above. The squares are 10um. The color is an artifact of the microscope technique; DIC (Differential Interference Contrast). The very sharp scissors used to section the film do not give a clean cut, but you can see the emulsion/base strata. I think the separation feature in the base is the integral mask--the yellow filter that separates the yellow (blue) emulsion layer from the cyan (red) and magenta (green) emulsion layers (film is a subtractive color process, hence the cyan, magenta, yellow emulsion/dye layers). The integral mask gives color negative film its distinctive orange cast and is used to control color contamination to the other layers as all are sensitive to blue (color transparency film removes the filter dye in the development process).

Obviously, the emulsion is on the lens side. The base will also have an antihalation backing to absorb the light passing through the emulsion and base being reflected back through the film. I suspect black and white emulsions to be thinner as they only need one "channel." Also T-grain technology that increased the efficiency for the grains to cut out light would impact emulsion thickness: silver is the most expensive component to the emulsion and so any increase in efficiency to reduce silver was good. The chemistry for color film where the sliver image need to be then converted/developed into a color dye image might also make color emulsions thicker. Given that, I suspect the color emulsions would be the upper limit to emulsion thickness.

I probably don't need to tell you this, but light would not focus to a point, but to an Airy disk. So the point spread function is a bit more complex than a geometric illustration where things like f-number impacting image formation. I am more putting this in for others that might not know the problematic dilemma of light having the properties of both a wave and particle just so they can follow. We had a previous conversation where folks got a little lost.

 

[MGrayson]

Emulsion thickness was always a trade secret with film manufacturers. So the fact you cannot find a number is not surprising. However, having run a microscope lab, I attempted to answer this. This is color negative film with the emulsion to the bottom and the base above. The squares are 10um. The color is an artifact of the microscope technique; DIC (Differential Interference Contrast). The very sharp scissors used to section the film do not give a clean cut, but you can see the emulsion/base strata. I think the separation feature in the base is the integral mask--the yellow filter that separates the yellow (blue) emulsion layer from the cyan (red) and magenta (green) emulsion layers (film is a subtractive color process, hence the cyan, magenta, yellow emulsion/dye layers). The integral mask gives color negative film its distinctive orange cast and is used to control color contamination to the other layers as all are sensitive to blue (color transparency film removes the filter dye in the development process).

Obviously, the emulsion is on the lens side. The base will also have an antihalation backing to absorb the light passing through the emulsion and base being reflected back through the film. I suspect black and white emulsions to be thinner as they only need one "channel." Also T-grain technology that increased the efficiency for the grains to cut out light would impact emulsion thickness: silver is the most expensive component to the emulsion and so any increase in efficiency to reduce silver was good. The chemistry for color film where the sliver image need to be then converted/developed into a color dye image might also make color emulsions thicker. Given that, I suspect the color emulsions would be the upper limit to emulsion thickness.

I probably don't need to tell you this, but light would not focus to a point, but to an Airy disk. So the point spread function is a bit more complex than a geometric illustration where things like f-number impacting image formation. I am more putting this in for others that might not know the problematic dilemma of light having the properties of both a wave and particle just so they can follow. We had a previous conversation where folks got a little lost.

Will,

Thank you for some real data! I did not expect my analysis to represent an actual effect, although there seem to be a few pixels worth to play with. I was just surprised when I did the calculation that a thicker emulsion could, in theory, produce a sharper image. One's first impulse would be that the light rays at different angles would smear the image as they traveled through the emulsion.

As for the true properties of light, well, I'm a Mathematician and was, as the undergraduate physics texts would say, ignoring air friction, relativistic effects, and rust. :grin:

Matt

 

[Godfrey]

Maybe I missed it, but another major factor people are neglecting to mention is this (forgive me if it's obvious): Using a cropped sensor -- i.e., 44x33, even 48x36 -- on a V body means what you're focusing on in the viewfinder is smaller than it would be when shooting 6x6 film. You have to back up or use a wider lens to get the same view you want. Picture a lovely portrait of someone in the 6x6 viewfinder, waist at the bottom of the frame, top of head at the top of the frame. To get that image with a 44x33 sensor, you need to position your subject much smaller in the Acute Matte screen. It makes a huge difference.

I loved using the old Aptus 54S (48x36 sensor) on my V system, but it wasn't always easy to nail focus. The lenses definitely have their own unique look.

I talked about this up thread a ways. Essentially, for my lens kit, the difference is roughly one lens focal length. That is, instead of the 120mm, use the 80mm; instead of the 80mm, use the 50mm. I have four V system lenses now, moving to the 33x44 sensor (and cropping square for V system imaging format), I just drop down one focal length. Add the 907x and 21mm lens to replace the Distagon 50's position as my wide...

Diagonal Angle of View Table

f - 56^2 - 33^2
------------------
21 - NA - 96
50 - 77 - 50
80 - 53 - 33
120 - 37 - 22
150 - 30 - 18
250 - 11 - NA
​

I don't think what I'm focusing on is going to be all that much different that I can't accommodate it with the WLF magnifier or the focusing chimney magnifier. After all, I'm able to critically focus all of my lenses now and I'll get the same central spot view of the focus point whether I use 33x33, 33x44, or 56x56 format. The sensor to film difference is shown nicely in this illustration:

The sensor loses 6mm off each horizontal side and 11.5mm off the top and bottom. I've often cropped Hasselblad photos more than that!

G

 

[Godfrey]

There was a translucent plastic mask one could slide in, in between the screen and focusing hood. And the outer lines of some of the gridded screens corresponded to the 645 and Superslide (A16S) format.

It's certainly easy enough to cut a mask from a piece of thick black paper and slide it into the WLF. Or to scribe a set of format lines on my viewfinder screen. This isn't rocket science.

G

 

[Godfrey]

Will,

Thank you for some real data! I did not expect my analysis to represent an actual effect, although there seem to be a few pixels worth to play with. I was just surprised when I did the calculation that a thicker emulsion could, in theory, produce a sharper image. One's first impulse would be that the light rays at different angles would smear the image as they traveled through the emulsion.

As for the true properties of light, well, I'm a Mathematician and was, as the undergraduate physics texts would say, ignoring air friction, relativistic effects, and rust. :grin:

Matt

There's some data on actual Kodak film emulsion vs base thicknesses in the little book 'Making Kodak Film' by Robert L Shanebrook. For instance, one micrograph shows that Kodak T-Max 400 has two emulsion layers plus overcoat totaling 10.25 microns thick on a 125 micron thick acetate base. Another micrograph shows Kodak Ultra Max 400 has a 14 layer emulsion with a total thickness of 46.6 microns on a 125 micron thick acetate base.

The bases are all fairly regularly 125 micron (non "Estar" base), but emulsion thicknesses vary quite a bit depending on the specific film.

(This is a fantastically interesting little book if you are interested in how film is/was made. Robert Shanebrook is an ex-Kodak engineer and manager who documented Kodak's film manufacturing processes in elaborate detail after he retired, and self-published the book.)

G