Direct projection Wild M7A using phototube 404891 color correction?

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sreynolds
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Location: Vermont, USA

Direct projection Wild M7A using phototube 404891 color correction?

#1 Post by sreynolds » Sun Sep 18, 2022 1:07 pm

Does a direct projection method of attaching a camera to a Wild phototube have any inherent problem since it has no color correction via an eyepiece? I have a Wild M7A with phototube 404891that I intend to attach a Canon mirrorless camera to, using a Diagnostic Instruments D10NLC and a C-mount to Canon EF-M adapter. There is no lens in the D10NLC. Any problems here? Thanks.
Steve

jfiresto
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Location: Northern Germany

Re: Direct projection Wild M7A using phototube 404891 color correction?

#2 Post by jfiresto » Sun Sep 18, 2022 1:22 pm

That is what I do. Here is a directly projected image taken with an Olympus E-PL7 and the older Wild 376788 photo tube:

Image

(Click on the image to enlarge or to save the original.)
-John

Scarodactyl
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Re: Direct projection Wild M7A using phototube 404891 color correction?

#3 Post by Scarodactyl » Sun Sep 18, 2022 3:31 pm

It is the best method for Wild stereos that I have tried. The eyepieces are either neutral or close to neutral, and any corrections they might offer to the image seem to be overhwlmed by other issues with the added glass in the light path (not to mention the much larger visual field available with direct projection)

jfiresto
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Location: Northern Germany

Re: Direct projection Wild M7A using phototube 404891 color correction?

#4 Post by jfiresto » Sun Sep 25, 2022 7:42 am

My earlier image largely shows the chromatic aberration of the M7A objective at maximum magnification. I found a couple more from when I was considering direct projection onto a larger image sensor.

imaged1.jpg
imaged1.jpg (82.52 KiB) Viewed 1239 times
imaged2.jpg
imaged2.jpg (105.71 KiB) Viewed 1239 times

These are from a wide open Wild M7S, with the same objective but looking through the center, at the lowest and most challenging 0.6X magnification. I stuck with a 4/3-inch sensor.

I think you will be happy with the M7A once it is clean.
-John

I_lika
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Joined: Wed Sep 28, 2022 3:19 am

Re: Direct projection Wild M7A using phototube 404891 color correction?

#5 Post by I_lika » Wed Sep 28, 2022 3:36 am

jfiresto wrote:
Sun Sep 18, 2022 1:22 pm
That is what I do. Here is a directly projected image taken with an Olympus E-PL7 and the older Wild 376788 photo tube:

Image

(Click on the image to enlarge or to save the original.)
I want to say I've been following your posts and detective work regarding the m4/3 adapters for use with older 38mm Leica phototubes. I appreciate the time you spent looking into this. I am looking to duplicate what you have done, however the cost of shipping a Quenox m4/3 adapter to Canada is very expensive. Is there a possibility you can DM me and perhaps find a way for me to obtain one of these adapters?

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