About a year ago I tried some Efke 25 and found it needed to be exposed 2 stops below the rated speed. I recently tried some Adox CHS 50 and 100 and found them to be much closer and it appears they have a very different feel to them. There is much written about how they are the same film but it did not seem that way to me. Although it was ISO 25 vs ISO 50 and 100. Can anyone enlighten me in this matter.