RF 35mm IS f/1.8 vs 50mm f1.8 for travel/low light (night) shooting

[fbenjamin]

Just bought Canon R10 as my first camera (with 18-45mm kit) for casual hobby and travel photography. Primarily because I'm doing a hike up a volcano for 2 days and wanted to get some amazing shots of the views and volcano erupting at night... I am thinking of upgrading from the kit lens, wondering if its wort it... Being very new at this... wanted some feedback 

1. Will the image stabilization (IS) on the 35mm vs the 50mm (non IS) make a big difference in shots in the evening/night when shooting handheld? and same question if using a tripod for slow shutters speeds like 10-30 seconds, or will tripod alone be enough?
2. Will f/1.8 be too low of an f stop for shooting volcano eruptions at night? Or is something around f/4-6 better?

[Waddizzle]

Welcome!

1a.  Yes, having IS can really help when shooting at slow shutter speeds. 

1b.  The general rule of thumb says that you should disable image stabilization when the camera 

2. Smaller aperture values will give you greater depth of field. Of course, you will need to use slower shutter speeds. 

[shadowsports]

Greetings,

The RF 35 f1.8 would be a better option for night time photography on a APS-C based body.  The FOV on the 35 will be equivalent to 56mm.  

The 50 would provide a FOV equivalent of 80mm.  This can be a bit awkward and might better suited for portraiture.  

The faster aperture f1.8 would be approx 2 full stops faster than the RF-S 18-45 F4.5-6.3, so I feel you'll enjoy using the 35 and might find it more versatile for low light shoots.  

There are other lenses and directions you can go in. However, between the 2 lenses mentioned I feel the 35 would be a stronger performer on the R10 in a greater number of situations.