[Wayneheim]

I was on Amazon the other day and saw and ordered a "digital" back for my 4x5 Speed Graflex camera. It consists of a plate with a mounting bracket where you can attach you Pentax to the plate and then take the back off the Speed and attach the plate to it. This allows you to take a digital picture using the 70+ year old camera. Pretty cool. My SG has a 127mm lens on it. The problem is that to get it to focus at all I have to move the bellows all the way into the body of the SG, in the storage position, to achieve focus at about 20 feet.
Is there any way to adjust the focal distance so that I can extend the bellows and use them more traditionally to focus? I go to WWII reenactments and it would be cool to be able to take some picture with something like this.
Any help would be appreciated.
Wayne

[Wayneheim]

Where would you get corrective optics?

[TwoUptons]

I saw those backs some time ago, and it seems they would be much better suited to rail cameras, not press-style cameras.

You could find a longer lens for the Speed Graphic... There was a 147 or something, IIRC that would work, or any of the longer lenses...

-Eric

[beachboy2]

Can you put an extension tube on the SG?

[beachboy2]

whoops! of course. How about a camouflage blanket with the K3 under it and using the MF SG as it's meant to be used?
Good luck.

[stevebrot]

The problem is that to get it to focus at all I have to move the bellows all the way into the body of the SG

It looks like you have discovered the problem with LF/dSLR adapters. The sensor on your Pentax is 45.46mm behind the mount flange. As a result, the taking lens must be moved that much closer to the rear standard to attain infinity focus. With most LF cameras this means loss of most movements, if indeed the camera is able to collapse that far without "kissing" the lens rear element to the dSLR body

There are systems using the dSLR body as the rear standard in conjunction with a bag bellows that work with some success though the shortest usable lens is still likely to be in the 90mm or greater range.


Steve

[pacerr]

Use lenses with registration distances suitable for the bellows extension you want to work with. You need to account for the Pentax lens type RD (45.46mm) plus the additional bellows extension you want.

Here's an RD chart: http://www.graphics.cornell.edu/~westin/misc/mounts-by-register.html

You will undoubtedly need to fabricate a lens mounting plate compatible with the lens mount -- temporary trials with less than 'perfect' mounts will facilitate experimenting with lenses. You may even be able to use a mounting board with a 'set-back' to position the lens somewhat back into the bellows. I could describe a DIY recessed mount board via PM if you'd like.

Search on 'view cameras' to get a better idea of the universal solutions possible.

(I'm dealing with the opposite problem of accessing the controls of a GoPro-type camera mounted directly behind the lens plate within the bellows of a Press Graphic body.)

[stevebrot]

Wow and I was thinking that the use of an APS-C sensor was a shameful waste of all that glorious LF focal plane real estate

It is, but that is the next level of foolishness.

IIRC, Fotodiox (and possibly others) makes a Graflex compatible shift plate that facilitates stitched dSLR images of the full 4x5 frame using longer focal lenses on a view camera. With such a system you gain the advantage of the camera movements, but wide angle is still a problem.


Steve

[pacerr]

. . . the use of an APS-C sensor . . .

Not to use the sensor in my case. Just using a cheap GoPro knock-off housed within the 4x5 body as an attention-getter and conversation piece (a Q is just a little too big - maybe with a 5x7 body?). No actual lens involved, just a hood to disguise the fake.

Rigging accessible controls for the hidden body without trashin' the 4x5 body is a challenge.

[swestin]

Use lenses with registration distances suitable for the bellows extension you want to work with. You need to account for the Pentax lens type RD (45.46mm) plus the additional bellows extension you want.

Here's an RD chart: Camera Mounts Sorted by Register

You will undoubtedly need to fabricate a lens mounting plate compatible with the lens mount -- temporary trials with less than 'perfect' mounts will facilitate experimenting with lenses. You may even be able to use a mounting board with a 'set-back' to position the lens somewhat back into the bellows. I could describe a DIY recessed mount board via PM if you'd like.

Search on 'view cameras' to get a better idea of the universal solutions possible.

(I'm dealing with the opposite problem of accessing the controls of a GoPro-type camera mounted directly behind the lens plate within the bellows of a Press Graphic body.)

This page has been superseded by https://stephen-westin.com/misc/mounts-alphabetical.html; I haven't worked at Cornell for over 15 years, and I don't have any way to replace that page to redirect it.

– Stephen H. Westin

[MarkJerling]

Unfortunately the link you post in your latest post returns a 404 error.

[stevebrot]

This page has been superseded by https://stephen-westin.com/misc/mounts-alphabetical.html; I haven't worked at Cornell for over 15 years, and I don't have any way to replace that page to redirect it.

– Stephen H. Westin

Yay! Welcome to the Pentax Forums!

There is an errant ";" in the URL for your link. Remove it and your link should work. Leave it in and we get "404".

Alphabetical List of Camera Mounts

Unfortunately the link you post in your latest post returns a 404 error.

Mark, is this something you can fix?


Steve

[swestin]

Yay! Welcome to the Pentax Forums!

There is an errant ";" in the URL for your link. Remove it and your link should work. Leave it in and we get "404".

Alphabetical List of Camera Mounts



Mark, is this something you can fix?


Steve

Of course, you are right. The correct URL is "https://stephen-westin.com/misc/mounts-alphabetical.html".
But the original link was to the list sorted by register, which is here.

– Stephen