SWC Help

[vandevantersh]

My CFV back with the right angle battery plate wont fit on the SWC. The tripod mounting plate is just slightly too "high" to allow the back to fully engage the upper closure "hooks". The CFV without the bracket and a film back seat properly. Any ideas???

Steve

 

[vandevantersh]

Here she is...1972 SWC with 16S mask (42056) and CFV but no battery

Steve

 

[vandevantersh]

Well...25 years ago, my SWC could be modified to a quasi-SWC/M using a factory supplied kit (44059). It looks as if I want to use the CFV back with a battery, I will have to do a non-factory approved modification.

Steve

 

[polypal]

Hi Steve,

There is a battery adapter kit now to change the position of the battery on the CFV.
Early CFV backs were supplied with that adapter.
The adapter can be ordered if your CFV was not supplied with one.
BTW the 16S mask is looking very good!

Paul

 

[vandevantersh]

Hi Steve,

There is a battery adapter kit now to change the position of the battery on the CFV.
Early CFV backs were supplied with that adapter.
The adapter can be ordered if your CFV was not supplied with one.
BTW the 16S mask is looking very good!

Paul

I have the battery adapter...the tripod plate is about 1.0 mm too high to allow the back + adapter to latch into place. The SWC/M and later models that would accept the 100 Polaroid back would have more than enough clearance.

Steve

 

[polypal]

A full conversion kit to upgrade the SWC to SWC/M specification is no problem.
Might have just the spares to mount only the foot further away from the body as well.

Paul

 

[vandevantersh]

One small screw on the battery adapter plate was "high" and I removed it.

The 1.5 CFV crop vs the "full frame" is quite apparent with the SWC. I guess I will go the the freezer and resuscitate some film.

Steve

 

[Swissblad]

Steve,
glad thing worked out - it looks like a lovely camera - now get out and show us some photos of how the combination works.
Best
S

 

[macmx]

Generally, I have been disappointed with SWC+CFV results. Not very sharp at all.

 

[polypal]

Generally, I have been disappointed with SWC+CFV results. Not very sharp at all.

That generates questions:
Does the CFV back perform well with other bodies?
Did you use a film back with the SWC and what where the results?

Unless there is a problem with camera or back the SWC/CFV should give excellent results.
OOF can be caused by a number of problems.

Marcus, why did you not report this before?

Paul

 

[macmx]

I think that I have seen stated that the SWC's and CFV don't work well together due to "optical incompatibilities", whatever that means. Hasselblad also stated that the combination is "not recommended for critical use".

I don't use the CFV with my 905 anyway, because I need the wide angle. Also, you need to press and release the shutter really quickly to avoid weird magenta pictures, if you're not using a sync cable. This makes longer exposures much harder, which otherwise is one of the SWC's many forces.

 

[vandevantersh]

"Also, you need to press and release the shutter really quickly to avoid weird magenta pictures, if you're not using a sync cable. This makes longer exposures much harder, which otherwise is one of the SWC's many forces."

I haven't had time to "play with" the SWC-CFV combo...does the magenta problem still happen after changing the exposure duration of the CFV?

Steve

 

[polypal]

I think that I have seen stated that the SWC's and CFV don't work well together due to "optical incompatibilities", whatever that means. Hasselblad also stated that the combination is "not recommended for critical use".

Hasselblad refers to the fact that the rear element of the Biogon is mounted quite close to the sensor causing the light to hit the sensor at an angle for the part that comes from the edges of the lens.
The CFVs sensor is only 36X36 mm. This means that although the effect is there the influence is limited.

I don't use the CFV with my 905 anyway, because I need the wide angle. Also, you need to press and release the shutter really quickly to avoid weird magenta pictures, if you're not using a sync cable. This makes longer exposures much harder, which otherwise is one of the SWC's many forces.

Two chances:

Was the menu of the CFV set for longer exposures?
Second: The way the sensor is triggered by the SWC needs attention.

I tend to think the second option is the cause for the problem as it did not appear when using a sync cable.

 

[macmx]

Yes the exposure was set correcty. I was merely commenting on that with film, I can shoot at 1/15th sec handheld, which is not possible when having to press and release the shutter that fast.

Ernst Wildi says about 903/905 and digital backs:

"Used with 903SWC or 905SWC cameras. You must depress the release button rapidly to avoid a faulty capture with a magenta cast. You can avoid this problem by using the Flash Sync setting and use the Flash Sync cable to connect the lens to the digital back."

It seems that the IR filter and glass in front of the sensor combined with the wide entrance angle is a reason for spherical aberration, which cannot be compensated by stopping down.

 

[vandevantersh]

I am trying to get gear together for a "West" road trip but I shot a few quick exposure with the SWC-CFV...#1 is f11 set to 15', #2 is f8 at 20' and #3 is a crop of #2...I have no idea what I should be looking for but I did notice that the DOF and sharpness of #2 was better when set to 20' rather than infinity.

Steve

 

[vandevantersh]

""Used with 903SWC or 905SWC cameras. You must depress the release button rapidly to avoid a faulty capture with a magenta cast. You can avoid this problem by using the Flash Sync setting and use the Flash Sync cable to connect the lens to the digital back."
************
I tried the "B" setting with sync cable with the back set to Flash Sync or SWC. In Flash Sync mode the shutter closes in about 6-8 seconds while in SWC mode I can hold the shutter open for many seconds. I am going to try to take the SWC-CFV to Antelope Canyon in a few days so I am trying to quickly develop a strategy for "low light", moderate f-stop and long exposure using this combination.

Can the exposure duration that gives a good result with the CFV be used for film with the same ISO?

A couple of shots in a "dark" room with about the same light level(?) as the lower Antelope Canyon. Only adjustment was WB. #1=6 sec exposure, #2 10 sec exposure using sync cable with back set to SWC. Significant crop.

Steve

 

[macmx]

Steve,

Can you explain the two pictures above? I did not understand your post completely.

If the ISO setting of the CFV does not match film speed, something is wrong. It should be the same.

 

[vandevantersh]

Steve,

Can you explain the two pictures above? I did not understand your post completely.

If the ISO setting of the CFV does not match film speed, something is wrong. It should be the same.

Sorry for the confusion...The two pictures were taken in low light, about what I thought the light level would be in lower Antelope Canyon, AZ....the first at 6 sec exp. the second at 10 sec exp. Just "long exposure" practice with the new set up and checking for the "magenta" problem.

The question (unrelated to the pictures) is...If I take a low light exposure at, for example 10 sec, and the histogram & preview look ok on the CFV..if I then put a film back on the SWC and repeat the 10 sec exposure, (ISO 100 for both) will my film also be a good exposure?

Steve

 

[vandevantersh]

I don't have proper targets to evaluate lens/sensor geometry at the periphery but at least centrally, the CFV sensor plane seems to be in the "proper" optical position. I did a tight crop of the letters at the bottom of the color chart and the focus (done by measurement @ 8') seems to be OK. (Time for me to stop screwing around, I have 1,3k kms to drive tomorrow)

Steve

 

[polypal]

1.3 K Km at 60 Mph or 160 Mph? That is the question!