Tulip, a comparison digital, Zebra dryplate, Foma 100

[martin-f5]

I just wanted to clarify how it works and so it came all together
color, Fuji XT-4 35mm f1.4
second, Zebra dryplate, ISO 2, Nakaoga 4x5 with old Tessar 135mm f16, 8min, dev. in HC 110
third, Fomapan 100, ISO 100, Nakaoga 4x5 with Tessar 135mm, f16 3 min, dev. in Ultrafin SF

 

[Ian-Barber]

The dry plate looks nice Martin

 

[David M]

Interesting to see the differences in spectral sensitivity between the two monochrome images.

 

[Alan Clark]

Martin, as I understand it you used the same lens at the same aperture for the dry plate and the Foma 100 exposures. The Foma got 3 minutes and the dry plate got 8 minutes. This is less than 1.5 stops difference. Yet the dry plate, at ISO 2 is over 5 stops slower. The lighting looks the same, so I am a bit confused.....

Alan

 

[martin-f5]

Hi Alan,

I think it's due to reciprocity differences,

first of all the bellow extension was 200mm

for dryplate I had to double the time and recalculate it with bellow extension, and of course my Sekonic goes only down to ISO 3
probably it could get an extra stop for more details, but it looks fine to me

using Fomapan I use an app called "inverse" wich gives all I need to know

 

[Alan Clark]

Thanks Martin.

Alan