Voigtlander Angle Finder DIY SWC conversion

[Atom]

I recently got a Hasselblad 903 SWC. I don't like the finder all that much and wanted to get the Voigtlander Angle finder specially made for the square crop. Finding that they go for about $800 nos on ebay I figured this was a little silly. I was able to buy a brand new 35mm version at Photo Village in NYC (they only had a few left as of this writing) for ~$400 with all three of the attachments. This was regular retail and I'm fine with that. I decided I could probably convert this myself! So here goes...

First I had to remove the tiny screws holding the back cover on. There was a sticky residue or glue holding the edge by the screws on that I severed with an xacto. It lifted off without a problem after that. Underneath was a brass bar held in by 2 screws holding down the prism (sorry for the blurry photo of this).

 

[Atom]

I then carefully remove the prism which was not held in by anything else. This revealed the focusing screen. I then fashioned a tiny mask with piece of thin plastic card stock i had lying about. This step took me the longest and there was much trial and error getting it cut properly and not looking terrible through the finder itself. Fortunately there is a slight lip (the silver edge around the screen) that made it easy for the screen to just drop in once it was cut to the proper size. This seriously took me hours of cutting and different materials before I made one I could live with. I just didn't have the right clear acetate I wanted lying around to make it work. I may get something else in the future to replace it. For now I am going to field test this for a little while.

 

[Atom]

Here is the result. The first image is the new view through the 15mm attachment and the second the view through the Hasselblad made finder. Yes, the angle of view is a little wider but I didn't take a photo through the 21mm attachment yet for comparison. My Hassy finder is odd. When your eye focuses on the scene the markings are actually out of focus. When focusng on the markings with your eye the scene becomes out of focus. It really causes a headache in use. (btw, ignore the colors they look correct and the first image was a raw file from the new Ricoh GR in Capture 1 and it's not supported yet)

I'll post more in the future after use to see how accurate my diy project is!

 

[MikeL]

Nice work Atom, the view looks good.

 

[Atom]

Put the 21mm attachment on instead of the 15mm and it seems to be just about perfect. I don't know where I saw it but i read somewhere the specially made finder used the 15mm attachment. Perhaps the lines were designed so you could see some around the frame lines in the finder. In any case I'm just about honed in.

 

[Godfrey]

Congrats on your 903SWC! I had one in the early 2000s, sold it in 2004 to liberate money for other project, but missed it a lot. I bought a '78 SWC last December to replace it, and couldn't be happier.

Put the 21mm attachment on instead of the 15mm and it seems to be just about perfect. I don't know where I saw it but i read somewhere the specially made finder used the 15mm attachment. Perhaps the lines were designed so you could see some around the frame lines in the finder. In any case I'm just about honed in.

Just be aware that the lens is gathering considerably more subject area than the stock finder is showing. The standard Hasselblad optical viewfinder shows about 85% of the FoV, so a 21mm finder for a 35mm camera shows the right approximate diagonal AoV to match the SWC finder.

The actual FoV of the SWC lens on 6x6 is approximately equal to the short dimension (vertical) AoV of a 16-17mm lens on 35mm. If you go back to the 15mm objective for the Voigtländer finder, your finder image will match the lens actual FoV more closely.

This is why for precise work (critical close focus and framing), most SWC owners use the SWC groundglass back and a tripod.

An optical finder and zone focus make the SWC so handy for snapping photos of people and other casual scenes where precision and accuracy are irrelevant. ;-)

G

 

[sienarot]

The SWC has been on my wish list for years. In fact, there was a SWC/m that was sold here for dirt cheap a few years ago that I didn't jump on ($1400 with back). By the time I decided to go for it, it was gone. I'm almost ashamed to say I still think about that SWC/m every time I'm browsing through the classifieds here 🙁

 

[fred2511]

\thinking about doing the same thing with the 35mm version of this finder

 

[wai]

<snip>

Just be aware that the lens is gathering considerably more subject area than the stock finder is showing. The standard Hasselblad optical viewfinder shows about 85% of the FoV, so a 21mm finder for a 35mm camera shows the right approximate vertical AoV to match the SWC finder.

The actual FoV of the SWC lens on 6x6 is approximately equal to the short dimension (vertical) AoV of a 16-17mm lens on 35mm. If you go back to the 15mm objective for the Voigtländer finder, your finder image will match the lens actual FoV more closely.

<snip>

G

Sorry to necro, but I've had a CV angle finder for a while now with a 12mm and 15mm attachment. If I 'converted' it, should I use the 15mm or try and get a 21mm attachment?


Regards,

Wai

 

[jmanivelle]

Sorry to necro, but I've had a CV angle finder for a while now with a 12mm and 15mm attachment. If I 'converted' it, should I use the 15mm or try and get a 21mm attachment?


Regards,

Wai

Hi all, just been testing the DIY conversion today on a 135 low angle Voigtlander viewfinder!
I found out that the 15mm lens matches well the original SWC viewfinder , better than the 21mm attachment imo.
Did remove the prism and the glued piece around the frame , added a piece of translucid sheet of plastic (the kind used for xerox machines) on which I marked vertical lines for a square format with a thin marker.
Tried various positions of the lines till I hit the corresponding view from the original SWC finder. The lines are still rough and it sure was a quick and dirty job . The lines do appear even larger when looking into the viewfinder. Anyway it's a good start and I can improve the design for sure. For my hand held style of shooting, I'll be fine and I still can use the low angle finder for 135 film cameras.

Thought I'd share here and thank Atom, Godfrey and everyone on RFF for the inspiration 🙂

Cheers, JM.

 

[wai]

Thanks JM - I'll have to give this a go! Got some thin microsope glass cover slips that I think will work here. Bought them to fix a botched repair on a Wata Range Finder (co-incidentally also for close focusing on the SWC).

 

[Godfrey]

Sorry to necro, but I've had a CV angle finder for a while now with a 12mm and 15mm attachment. If I 'converted' it, should I use the 15mm or try and get a 21mm attachment?

Using the 15mm finder and masking it to a square nets the most accurate representation of the SWC FoV. It will be just a hair wider than the SWC sees.

The 21mm finder nets the closest to the SWC diagonal, if you don't mask, but it's harder to visualize the square frame that way.

G

 

[miatab]

This post reminds me of the little 24X24 Robot Star I had in 1960. It had a little slider on the top deck that enabled viewing at 90 degrees to enable unobtrusive image making.

 

[gatalau]

FWIW I use the Voigtlander zoom finder 15-35mm, you can easily switch between 15, 21 and 25mm (for vertical I use 15mm and then switch to 25mm for the horizontal FoV).It's quite accurate and a pleasure to use (and it is much cheaper than any legacy SWC solution if you do not have a viewfinder).

 

[SoheilK]

Not sure if this thread is still active. I’m going to convert my 35mm anglefinder but my guess is the frame will be smaller in the converted version than the original 6x6 frame. Is that right?

 

[imamontrealer]

FWIW I use the Voigtlander zoom finder 15-35mm, you can easily switch between 15, 21 and 25mm (for vertical I use 15mm and then switch to 25mm for the horizontal FoV).It's quite accurate and a pleasure to use (and it is much cheaper than any legacy SWC solution if you do not have a viewfinder).

Hi Gatalau, new to the SWC system. When you use the Voigtlander zoom finder 15-35mm, are there any square frame lines? Can you provide some feedback? Thanks