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New CFV back, arcbody and SWC

C

cheza

New Member
Can anyone clarify Hasselblad's comments about the unsuitability of the SWC and Arcbody with the new CFV back.

I have used a PhaseOne P25 succesfully with my SWC and within the last few weeks found I can fit my P25 on my Arcbody with stunning results. For some images on the arcbody and all on the SWC I need to shoot a frame through white perspex to obtain a LCC correction in Capture One. This works well.

Does Phocus have the same facility?

Now I have found my Arcbody can be used digitaly I am looking at a 39mp back. The new CFV is attractive.

Can anyone help with info.

PS Hasselblad - reintroduce an arcbody that will take digitar or other LF lenses - you would be on to a winner.
 
Large DB with older lenses.

Several manufacturers of DB with large sensors warn for the use of certain lenses cameras with these backs.

In principle the light should reach the sensor under a 90° angle.
With cameras where the last element of the lens is close to the film surface or the DB the light coming from the edges of the rear element will reach the film/DB under an angle considerably smaller than 90°.

That can cause problems with the way the pixels at the edge of the sensor are hit.

In practise this problem seems less serious than theory indicates.
In fact using the largest sensor now commercially available in the Phase One P65 back does not cause a serious problem with SWC bodies.
The SWC is one of the camera systems where the rear element of the lens is close to the sensor.
 
Without doubt our dear forum colleague jotloob will put his new CFV39 onto an SWC to show us the results. Even comparison shots with the older CFV we might be able to sweet-talk him into... :z04_smileys70:

Wilko
 
CFV39 and SWA

I doubt whether these tests will do any good.
Jürgen has mentioned he will weld the CFV39 permanently to the SWA camera as soon as it arrives ..........
 
Lens casts

I know the theory about angles of light and the sensor. What I was particularly interested in knowing was whether Phocus could deal with the lens cast issues ie cyan tint in top left of frame. This is the same
thing thAt affects the Leica M8.
I haven't noticed sharpness issues with my P25 which is thesame format as the new CFV
 
cheza said:
I know the theory about angles of light and the sensor. What I was particularly interested in knowing was whether Phocus could deal with the lens cast issues ie cyan tint in top left of frame. This is the same
thing thAt affects the Leica M8.
I haven't noticed sharpness issues with my P25 which is thesame format as the new CFV
Click to expand...

I have not used a 37x49 sensor back like the CFII-39 or the H3DII-39 with my V-SYSTEM cameras yet and the CFV-39 is still not available .

I did not experience a cyan cast in the left top and/or a magenta cast in the right top of the image , when using the CFV with the 905SWC or the RODENSTOCK APO-SIRONAR DIGITAL + LF camera + CFV back .

When using the RODENSTOCK APO-SIRONAR DIGITAL 35mm lens with the ARCA-SWISS 6x9 and doing a 3x3 stitched image , I receive the mentioned cyan and magenta cast for the shifted image positions .

This can be corrected in PHOCUS by using an own white balance image for each shift position . This technique is actually called LCC .
Lens Cast Correction .
You have to shoot an own WB image for each shifted position .
That means , you shoot your image and your own WB image . Then do the next shift and repeat this for all positions for your planed stitch-image .

Phocus then can correct your image with its corresponding WB image .
You will have to name each WB image in order to use it with the corresponding image .

If you want to do a LCC for an image shot with a CFII-39 back attached to an SWC , you only need to shoot one WB image of course .
If you want to use that procedure for the SWC setup is up to you , of course .
I have never used it for my setup : 905SWC + CFV back . But here the sensor is just 37x37 mm .

Jürgen
 
Thanks Jurgen

I wasn't sure if Phocus handled LCC. It obviously works the same as using a PhaseOne back and CaptureOne.
 
cheza

The description from my last post has not grown in my head , but I have learned that from users in an other forum .
A wonderful exhange of information .

Jürgen
 
Cfv-39

Hurray :z04_carrot::z04_carrot::z04_carrot:

My CFV-39 is on its way to my dealer and will be shipped to me on Tuesday/Wednesday .
I am very excited . Come here CFV-39 :z04_whip2_1:
But leave TILT SENSOR at home .

Jürgen
 
Go, Jürgen!!

Once you get it, would you be so kind as to post a raw sample file from each ISO (50,100,200,400,800)? Happy to provide the web space to share with others from the board, if desired.

Also once you get it, I would like to ask a few things:
* How long from shutter release until the image shows on the back's screen?
* Does the back provide a multi-channel histogram, or just a single channel histogram?

I'm excited for you too! I hope this back delivers! :z04_xmas_wave:
 
polypal said:
I doubt whether these tests will do any good.
Jürgen has mentioned he will weld the CFV39 as soon as it arrives permanently to the SWA camera..........
Click to expand...

Ah, so he is gonna drill that hole in the CFV39! Good. Lets hope the drill does not hit the tiltsensor though.

Wilko
 
bradleygibson said:
Go, Jürgen!!

Once you get it, would you be so kind as to post a raw sample file from each ISO (50,100,200,400,800)? Happy to provide the web space to share with others from the board, if desired.

Also once you get it, I would like to ask a few things:
* How long from shutter release until the image shows on the back's screen?
* Does the back provide a multi-channel histogram, or just a single channel histogram?

I'm excited for you too! I hope this back delivers! :z04_xmas_wave:
Click to expand...

Brad

No problem . I will try to give you all the desired info .
I will come back with detailed questions , as far as the RAW files are concerned .

Jürgen
 
I don't think those Rodenstock film lenses for Arcbody are good enough for 39Mpx digital backs, such as CFV-39. I have also compared 903SWC with Schneider 35XL digitar, the 38mm Biogon does show some color fringing and lens cast problems on Phase One P25, and instead, the 35XL digitar is considerably better.
 
filmcapture

If you read my post carefully , you will notice , that I was not talking about an APO-SIRONAR S 35mm lens for use with film .
That lens does not exist anyway . Also , I was not talking about an APO-GRANDAGON 4,5/35mm for an ARC-BODY .

I was talking about the APO-SIRONAR DIGITAL 5,6/35 mm , which is not designed for use with ARCA-SWISS LF alone
(I was not talking about ARCBODY) but for use with any LF camera , which can adapt any digital back .

This lens is designed for the use with digital backs with a pixel size smaller than 9 micron .
And the RODENSTOCK APO-SIRONAR DIGITAL 5,6/35mm can be compared with the SCHNEIDER XL DIGITAR 35mm .

The PDF file from Rodenstock is too big to load it here , but you might want to visit the LINOS homepage , where you can find all details .

Jürgen
 
It's true the Rodenstock Apo-Sironar Digital lenses can be used for 9um sensors, but they are not good enough for these 6.8um 39Mpx sensors (http://schneider-kreuznach.com/knowhow/digfoto_e.htm). That's why Rodenstock developed new HR lenses. You may compare the MTF's of HR and no-HR lenses. I recall Bob Salomon with HP Marketing ( the Linos US distributor) mentioned in somewhere that Rodenstock did not consider the Apo-Sironar Digital lenses were truly "digital" lenses since they were just slightly improved from exiting film lenses.
 
What type of images are you looking for ? ? ?

bradleygibson said:
Go, Jürgen!!

Once you get it, would you be so kind as to post a raw sample file from each ISO (50,100,200,400,800)? Happy to provide the web space to share with others from the board, if desired.

Also once you get it, I would like to ask a few things:
* How long from shutter release until the image shows on the back's screen?
* Does the back provide a multi-channel histogram, or just a single channel histogram?

I'm excited for you too! I hope this back delivers! :z04_xmas_wave:
Click to expand...

Brad

My CFV-39 has not arrived yet , but will hopefully in the next couple of days .
Please let me know what type of images i can shoot for you .
Sky , grey wall , big adverts or whatever .

Jürgen
 
jotloob said:
Please let me know what type of images i can shoot for you .
Click to expand...

Great! So now we don't have to actually buy a digital back ourselves - we just ask Jürgen to go out and take the pictures. Really good idea. Thank you in advance. (Oh, and by the way, for my picture, please just take something fantastic - anything will do!)

:z04_5769:
 
Hello Jürgen,

There is this strange tree at the North Cape that could be a nice subject for a high res image could you take a picture of that for me?

I realise it is not around the corner but there is no other way to get it.
Let me know when you have a couple of weeks time to go there:z04_schlaumeier:


Paul
 
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