1/4 plate digital image

[pgk]

9 shot 'step & repeat' stitch on Arca using Sony A7II. Lens is a Grubb from 1865.
https://www.largeformatphotography.info/forum/attachment.php?attachmentid=250877&stc=1&d=1719221836

[Mark J]

Any chance of a bigger file, Paul ?

[pgk]

Not sure via the forum, but I'll email you a higher res version.

[Mark J]

Thanks got that - quite impressive. How much field does that cover ?
ps. if you want to link a bigger file, I usually use imgbb.com.
I think you take the option 'full bb code linked' when your file is uploaded, and copy that into the thread.

[Tin Can]

Now I see what you call Step & Repeat!

To me it is something way different

People on podium

[pgk]

Thanks got that - quite impressive. How much field does that cover?

The lens used was originally intended to cover from 6" x 5" up to 9" x 7" depending on the position of the stop and the degree of acceptable distortion. So I'm currently using the central area of about 1/4 plate or 3 1/4" x 2 1/4", but will eventually be able to sample a greater area. As far as I can tell the real limiting factor appears to be image curvature, and contemporary articles suggest optimal stops to maximise image 'clarity' which was undoubtedly a trade off of a number of factors such as stop position, stop size and also subject distance. I'm tending to think that performance is often better at closer focus than at infinity.

[Mark J]

Here in widescreen !

https://i.ibb.co/SVq7Nwy/Grubb-A0.jpg (https://ibb.co/vL2v14q)
upload a photo (https://imgbb.com/)

[pgk]

A couple more, both from an 1864 Grubb Doublet.
The vessel is a 4 image stitch and sufferes from some veiling flare as the lens is uncoated obviously and not exactly pristine either. Surprisingly good at resolving detail given that it was most likely intended for stereo photography (3"x3" or 4" x 4").
The scene made up from 16. The castle is at Lochranza and was photographed in 1862 by Thomas Annan of Glasgow who may well have used a Grubb C lens which he owned to do so. A print is in the National Library in Edinburgh.
The Arca works fairly well for such photography although a little heavy and unweildy. Cost for such lens 'testing' is low as no film is involved which is a benefit!
252277
252278

[pgk]

And FWIW a 9 shot close up using some movements. Again, considering this is taken with an 1864 lens I am quite impressed!
252310

[Tin Can]

Good idea and execution

I will follow, but in Black and White


A couple more, both from an 1864 Grubb Doublet.
The vessel is a 4 image stitch and sufferes from some veiling flare as the lens is uncoated obviously and not exactly pristine either. Surprisingly good at resolving detail given that it was most likely intended for stereo photography (3"x3" or 4" x 4").
The scene made up from 16. The castle is at Lochranza and was photographed in 1862 by Thomas Annan of Glasgow who may well have used a Grubb C lens which he owned to do so. A print is in the National Library in Edinburgh.
The Arca works fairly well for such photography although a little heavy and unweildy. Cost for such lens 'testing' is low as no film is involved which is a benefit!
252277
252278

[pgk]

After some refining I've tried the Arca M/F hybrid out hiking with the 1864 stereo lens shooting about a 6x9cm image. This requires a 9 shot stitch but on the right subjects can work surprisingly well.
252969

[Mark Sampson]

A fascinating approach and a demanding technical challenge. Well done! Those old lenses can be quite good- "they built better than they knew".

[pgk]

They certainly can be effective - I'm finding it to be quite a learning curve! I have to work quickly in case light and clouds shift - yesterday when the photo here was taken was windy and several images show artifacts due to rapidly shifting conditions, but this one is ok. [9 image stitch].
253055

[pgk]

And a 15 shot stitch from today - excceds the 4" x 4" intended format as the image is ~5" wide and soft with vignetting at either end. Centrally it remains very good with flare handled extrememly well for a far from immaculate lens from 1864.
https://www.largeformatphotography.info/forum/attachment.php?attachmentid=253548&d=1727282913

[pgk]

From today using a TTH Cooke Series III 4.4" f/6.5 lens - 9 image stitch at about 6x8cm format.
255035

[pgk]

One taken slightly differently. Slight refocus on each shot has in effect extended the depth of field in the 3 image stitch from an 1862 Grubb Petzval and ensured that the image is sharp throughout. An A3 print would be acceptable to all but the most fastidious of viewers!
256391

[Martin Aislabie]

One taken slightly differently. Slight refocus on each shot has in effect extended the depth of field in the 3 image stitch from an 1862 Grubb Petzval and ensured that the image is sharp throughout. An A3 print would be acceptable to all but the most fastidious of viewers!
256391

Lovely.
Where is it ?
Martin

[pgk]

Fisherman's Walk, Brodick, Isle of Arran

[Martin Aislabie]

Fisherman's Walk, Brodick, Isle of Arran

Thanks
It is one heck of a shot
Martin