mike rosenlof
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I had a good trip to Maui in 2014. Took a Voigtlander 75mm/2.5 on a Leotax. That single lens worked well for me, but I've always been a slightly long user.

I'd normally gives a slight edge to the 35, but with the Canon P vf being so much better for 50, stick to that. I don't think I could compose 35mm shots well with it.
City or country? If Maui, go wider. If Oahu, there's city traffic & more historic landmarks. Other islands: views and jungle. I just returned from a chill week in Hana, mostly shot 21mm.
kB formerly of HI
Personally, I like to take a 28mm or 35mm on the camera and sneak a 50mm or 90mm into my wife's purse. That way "I" only brought one lens. í*½í¸�
It takes time to familiarize oneself with a new focal length, even when the jump is only from 50mm to 35mm. Perhaps an important vacation is not the best time to do so. But as others have said, how much weight and bulk would another rangefinder lens entail? I would suggest bringing a 35, but sticking to the 50 for most shooting.
If I had to take only two lenses on a trip, it would be the 28 and 50. If one lens, the 35, but that focal length has always seemed to me to be an unsatisfactory compromise, and one that usually isn't necessary. Speaking only for myself, of course!
Oahu.
Good, the film supply on other islands is pretty poor these days.
In Honolulu you have Treehouse Photo. Have a great time!
Oh really? Why is it better for 50? Just the frame-line layout?
Well, a 35 captures twice the area that a 50 captures at the same distances - to me that's quite a difference. But it doesn't require a totally different way of composing like a serious wide angle.Congrats on the 35mm lens! on infinity, close up.
Compare views to 50mm. It's truly a only lil wider..
For using 28mm on the Canon P I would need a 28mm viewfinder, right? Any recommendations in the event I ever try that out?