Very nice of you both! No, and I've rarely been known for my patience, either UHH was my first online forum ever, and I made the conscious decision early on to be (mostly, not 100%) nice. I want to feel I'm part of the solution, not the problem, of this forum's occasional incivility towards sincere questions and issues.

Aside from that, I apparently have a way of writing that newbies can relate to. Many technically experienced folks seem to not even be aware they are speaking "over the head" of the OP. I think there is an art to writing concisely and including just enough information. But I constantly edit what I post! It has almost become obsessive. And each year it's getting harder to access the right adjectives and verbs too

Well, from my perspective, you do a great job sharing your knowledge with newcomers like myself. I sincerely appreciate your time and thoughtful answers. My brother lives in Yakima and I was raised on a homestead not far from Royal City. If I find myself there, I’ll send you a personal message. I’d love to meet you. Thanks again for your help.

Thanks so much.

My husband and I have booked on a small boat repositioning cruise from Alaska for the first two weeks of September. I recently bit the bullet and bought a Canon 100-400 L lens that I love and use as my primary lens and especially for wildlife. I also have an older Sigma 18-35 lens that my son gave me. We drove home from Colorado through the San Juan Mountains and I tested it there. Please take a look at these photos and see if you think the Sigma is adequate for landscape pictures in Alaska. I'm not anxious to make another major investment but I don't want to be disappointed with my photos. I should add that I'm a relatively new photographer.

My husband and I have booked on a small boat repositioning cruise from Alaska for the first two weeks of September. I recently bit the bullet and bought a Canon 100-400 L lens that I love and use as my primary lens and especially for wildlife. I also have an older Sigma 18-35 lens that my son gave me. We drove home from Colorado through the San Juan Mountains and I tested it there. Please take a look at these photos and see if you think the Sigma is adequate for landscape pictures in Alaska. I'm not anxious to make another major investment but I don't want to be disappointed with my photos. I should add that I'm a relatively new photographer.

My husband and I have booked on a small boat repositioning cruise from Alaska for the first two weeks of September. I recently bit the bullet and bought a Canon 100-400 L lens that I love and use as my primary lens and especially for wildlife. I also have an older Sigma 18-35 lens that my son gave me. We drove home from Colorado through the San Juan Mountains and I tested it there. Please take a look at these photos and see if you think the Sigma is adequate for landscape pictures in Alaska. I'm not anxious to make another major investment but I don't want to be disappointed with my photos. I should add that I'm a relatively new photographer.

The 18-35 range puzzles me. I have an old sigma
that is 19-35, so I don't know how similar, or not,
my experience is. My experience is that the lens
is quite capable image-wise, but not to be trusted
AF-wise due to mechanical backlash.

-------------------------------------------------

Seems like many old AF lenses were built rather
loosely [all brands incl OEM] to let them move a
bit faster. This is not great for accuracy but having
participated in the initial migration to AF I can say
that at the time we were all habituated to MF, and
more or less knew that AF was better reserved for
hurried work at mid-to-smaller stops. IOW, we all
knew how far to trust the AF lenses of that era.

But now, a few oldies still in circulation get in the
hands of the "AF generation" who were born into
a time of reliable, accurate AF lenses, and today's
users might not realize the limits of the AF oldies.


`

Please invest a bit in a new lens for the trip. Tamron has a 18-200mm that would be versatile and compliment your incredible 100-400mm. The lens is modern with good IS and will give you satisfaction far beyond the current anticipated trip. It fills the gap you currently have with just one lens. You will be disappointed by keeping the current 18-35mm as it does not seem to work well. No amount of diopter adjustment will help seeing as you are using AF and the diopter has absolutely nothing to do with the camera AF.
Enjoy the trip.