One-Touch vs. Two-Touch Zoom
I've bought a Canon FTbN on eBay and would like to buy
a wide zoom and a long zoom to go with the 50mm, f/1.4.
One choice is a Canon 28-85mm, f/4.0 and a Canon
85-300mm, f/4.5 (both are two-touch zooms).
The other choice is a Vivitar 28-75mm and a Vivitar
75-300mm, f/4.5 (both are one-touch zooms).
What are the pros and cons with respect to handling
a one-touch zoom versus a two-touch zoom? Is one
easier to use, easier to focus, or optically better?
It depends. I find that two touch is fine if you have the time to preset your focal length and then shoot (or use an autofocus camera), but I prefer push-pull for when I need to change the FL a lot, and quickly. In practical use, I prefer push-pull myself, but I also think the drawbacks of two touch zooms have been negated by autofocus. Therefore, I don't mind two touch zooms if I am using an AF camera.
The maximum t stop of the lens will determine how easy it is to focus; not one touch or two touch focusing.
"Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."
- Rob Tyner (1944 - 1991)
I have one one touch zoom, a Vivtar Series I 28 to 105. I don't like it. It has a tendency to creep. The focal length drifts too easily. I think the two touch zooms are better in this respect.
I agree with 2f/2F. with a MF camera, pushpull for the added ability to change focal length on the fly. AF, I tend to like 2 touch more.
Vivitar Series 1, 28-90 f/2.8-3.5 or the Kiron 28-105. Both are excellent one-touch zooms.
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
On manual focus cameras with one-touch zooms, you get the focus easier at the longer zoom, than just slide it at the desired focal length. But be careful, there are very few zooms that do not preserve the focus when changing the focal. Between these, if I recall, is a short zoom from Vivitar S1 (Kiron) 28-80mm (or something like that). Although those few zooms are optically beautiful. Or am I wrong, and this is a two-touch zoom? I’m not sure anymore, as I avoided it years ago for this same reason.
As for AF cameras, using a one-touch zoom means to deactivate the AF. Two-touch zooms are best used with AF, as one-touch zooms are with MF.
Two-Touch is my preference, but that may because I greatly prefer fixed focal length lenses to zooms.
I wonder if there is any correlation between those preferences?
I use the Canon FD 75-150 and 100-300 zooms they are both one touch, I would prefer two touch because I find that it's difficult to use the trombone action without turning my wrist and knocking the image out of focus.
I have both types but prefer the two-touch. As mentioned the one-touch tends to creep if not held level. It can be a pain if pointing up or down unless you hold it in position.
I have used both, and like them both. But if push came to shove I'll go to two touch zoom. BTW welcome to APUG.