So, after having long desired to own a portrait-specific lens, I could finally purchase the 250mm Rodenstock Imagon, in Compound 3 shutter. I would like to ask few questions to fellow photographers, in order to get nice images without too much costy and time consuming trial & error at first.

To begin with, this lens doesn't use the standard "f" values for aperture: everything is calibrated in "h". I'm not familiar with "h" and I would like to understand if, in practice, it is more or less the same, or how should I adjust the lightmeter. (Should anyone have a link to some theory behind "h" values, I would like to read the paper, thank you).

The second question is if this lens can also be used without any of the "scolapasta" diaphragms in front. I have seen pictures taken with them in which dot highlights are rendered as stars, and I don't really like these kind of cheesy effects. By the way, the hood is basically just a piece of tubing and I can hardly imagine that it wouldn't vignette the image at full aperture. Also, has anyone ever tried to use the Imagon with neutral grey filters to control light, perhaps? I ask because the maximum speed of the shutter is insufficient to deal with sunday light at full aperture.

Third question: the Compound shutter comes with a magnificent, although uncalibrated, 17-something blades aperture diaphragm. Has anyone ever tried to use the Compound built-in diaphragm instead of the plug-in "scolapasta" accessories? Or is it placed in a wrong position for this type of lens, and won't work well?

Should anyone have any other kind of comment concerning the use of this lens, I'd be very glad to read. Thank you.

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