Ferrania P30: curve shape and (un)coated lenses

[Harry Callahan]

No, Henry. Modern multi-coatings increase light transmission. That is one main purpose they are designed for. Period.
You should compare a modern coated lens with an old uncoated lens, and then you will see that the modern lens offers better shadow detail.
If all the improved coating technologies of the last decades would have resulted in less shadow detail as you claim, lens designers would definitely not have used them.
And as already explained, I have lots of these different lens types with different coatings. I have the evidence in my work here.

Best regards,
Henning

Yes, coating does increase transmission - because it does reduce reflection. Fewer reflection = fewer flare. More reflection = more flare.
I don`t claim fewer shadow detail with a coated lens. I claim shadow detail to drop into a lower Zone. I also did some shots at night with mc lenses. Shadow detail was on the negative but printed black entirely, because density was too low. I had to dodge to get some back. With an uncoated lens flare would have been exposed additionally onto the film raising shadow detail to a higher Zone.

 

[Henning Serger]

I am thankful for the answers and i don`t want to waste your time, but what term am i meaning then if "flare" isn`t correct?

To get a better assessment of the phenomenon flare: Please have a look at the lens test source "lenstip". There every tested lens is tested for flare and ghosting.
Here just one example for a lens which is suffering from quite heavy flare:

Mitakon Speedmaster 85 mm f/1.2 review - Ghosting and flares - LensTip.com

Best digital cameras and lens reviews. If you are looking for the information about digital cameras and lenses you are in a right place. We have many professional tests of digital photography equipment.

www.lenstip.com

Even with a mc-lens you get flare when shooting direct into the sun for example.

No, not generally. I have lots of photos with the sun in the picture, and without the flare phenomenon. And there is the whole genre of "sun-star" photography which proves that with modern-coatings flares aren't a problem with direct shots into the sun.

The same situation does occur with an enlarger and the condenser only will produce more flare as it will produce reflections between film, lens and light source. People use glass-less negative carriers to improve contrast of the print, because a glass carrier also does produce flare.

No. I don't have that with my enlarger at all, and not with my glass carriers either. Which are used for film flatness, and not for flare production.

Final word: If you think you can reach your goal with uncoated lenses, just try it. My experience and test results have shown to me that that approach will not be successful with a film like P30.

Best regards,
Henning

 

[Harry Callahan]

Yes, these are the obvious artifacts of flare. But there also is a less obvious effect of flare, when flare is evenly shed across the entire negative.
If you use a fixed focal lens and stop down sufficiently, you won`t get flare in direct sunlight with a mc lens. But i wanted to point out that you even can get flare with a mc lens, because every lens does produce flare. You won`t notice all the time but every lens does, even mc lenses.

I`m sorry but also you suffer flare with your enlarger. If you could have your glass carriers and condenser lenses multicoated, you had higher contrast prints all the time - as the optical elements in your enlarger also do produce flare and by that reduce contrast on the print.
Of course glass carriers are used for film flatness, but they also do reduce contrast on the print because they produce flare - which is why some use glass-less carriers, though these cannot hold film flat.

Best Regards,

 

[Henning Serger]

Henry, we're going in circles here. It does not make sense to waste more time. You are totally convinced that your approach will work. Fine, just do it, go that path.
I've made detailed tests with P30 and almost all other current films on the market. My test results indicate very clearly what works for changing a CC, and what fails in changing a CC.

Best regards,
Henning