Arca F/Monolith as a step and repeat camera for static subjects.

[pgk]

I've been working on the idea of a 'step and repeat' camera for quite some time and finally got my act together and paid out sufficient to at least get the project rolling forward. The Arca monolith section allows the Sony EVF camera to be moved vertically and horizontally and so to sample different sections of a larger format image projected by the lens being used. In my case the lenses I have are mostly fairly early Grubb (1860s) with some later Grubbs, Dallmeyers and TTH too. The advantage for me is that the result is straight to digital, so there is no film cost for testing these lenses and with refinement the camera should be relativle portable and might be usable in the field if the conditions allow.

Here's my second attempt - a 9 image stitch of ~150-200MPixel equivalence with a ~6x9 or 1/4 plate covered area. It was taken on a lens similar to the one used as subject matter by abvailable light and is not perfect but shows the potential.

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[bdkphoto]

Doesn't seem particularly practical - even for just evaluating the old lenses. What's your ultimate goal for all this work?

[pgk]

Actually it works rather more straightforwardly than I had hoped and my goal was (and is) to evaluate early lenses. A friend did a cursory examination of an early Grubb design using lens design software so I have some MTF data to work from too. My background is in Photoscience so perhaps I have a slightly different take on practicality? But I will also try lens out in the field when opportunities present themselves.

[Mark Sampson]

Well, it's really a small optical bench, one that you can take out into the field. So a true dual-purpose device...

[Mal Paso]

Fotodiox makes a step and repeat adapter for many digital cameras and fits 4x5s with graflock backs. I have the Nikon F model. It was designed to combine 4 or 6 exposures into a single picture.

How does your adapter back achieve a light seal?

[pgk]

Fotodiox makes a step and repeat adapter for many digital cameras and fits 4x5s with graflock backs. I have the Nikon F model. It was designed to combine 4 or 6 exposures into a single picture.

How does your adapter back achieve a light seal?

I've seen the Fotodiox advertised but none are available for Sony apparently (backorder). At the moment I'm just using black card baffles which snug up against each other and this works surprisingly well. Eventually, finance permitting, I will modify it and get some bellows which I can connect directly onto the camera. The limiting factor on my set up is primarily 'vignetting' caused by the adapter used to extend the camera forward to the baffle (essential due to the handgrip) and the camera throat itself, both of which eventually 'shadow' the sensor at significant offset. That said I'm actually impressed with ease of use and lens 'quality' which is proving to be substantially better than anticiated. For static subject matter it will be uable in the field once I've refined and lightened it.

[Mal Paso]

I've seen the Fotodiox advertised but none are available for Sony apparently (backorder). At the moment I'm just using black card baffles which snug up against each other and this works surprisingly well. Eventually, finance permitting, I will modify it and get some bellows which I can connect directly onto the camera. The limiting factor on my set up is primarily 'vignetting' caused by the adapter used to extend the camera forward to the baffle (essential due to the handgrip) and the camera throat itself, both of which eventually 'shadow' the sensor at significant offset. That said I'm actually impressed with ease of use and lens 'quality' which is proving to be substantially better than anticiated. For static subject matter it will be uable in the field once I've refined and lightened it.

I have a bit of the same problem as the Nikon F adapter opening is smaller than the sensor. I should have gone Mirrorless at that point as the Z lens attachment is Huge. Fortunately the overlap is large and should be enough.

I had to wait for my adapter, it was out of stock for 6 months. I was notified by B&H that they were in production again, placed an order and waited some more. Largest full frame images 60x78mm and 90x44mm using 6 exposures each.