Just share my 2 cents after some research.. I also think about this question before and I'm using DX body.
It's depend on what type of photo you shoot. Below are some of the common point for both lenses.
- Low light capability (f/1.8)
- Both AF-S so auto focus for those no built in motor body
- Bokeh.. ? Should be the same right because both have f/1.8 aperture? But take your kit lens and shoot at 35mm & 50mm around f/6(make sure both focal length got same aperture), make the background as far as possible from your object. But make sure your object the same size for 35mm & 50mm, it's mean move closer and further to get it with same object size. Then you will know what's the different.
Pro & Con after using both lenses.
35mm f1.8g
Pro
- Can do group photo. (But do you really need f/1.8 for group?)
- Can do full body portrait
- Can be a good walkabout lens
Con
- Not good as a portrait lens. Especially half body and worst for head shot(shoot model with only face shown). Why? Because too short focal length. "But I can walk closer to shoot.." 2 bad things I can share when I walk too close to my friend.
- Distortion.. Try stand very close to your friend and shoot... You will notice your friend's nose getting bigger when you getting closer...
- Stress.... Your model will feel stress if camera too close to her.. This happened to my object, most of them can't act natural when camera too close to them.
50mm f1.8g
Pro
- Good portrait lenses for DX body because after crop factor it become 75mm which very close to full frame popular 85mm portrait lens..
- Cheaper... You could get a brand new at $285. But 35mm cheapest I found is $330. (Don't pm me on this, just walk around and ask and ask. Face thick thick sometimes gain some benefit)
- When you shoot portrait outdoor with 50mm f1.8.. The result i really like it so much on 50mm f1.8D. 50mm f1.8g only tried once.. Looks like the same but some peoples said it's better.
Con
Very obvious... Too long focal length for walkabout, group photo & indoor.... But if you always go shoot car model, IT show or cosplay etc.. 50mm recommended.. Don't be the unique one that stand so close while other stand quite far to shoot....
So what to use during event or gathering at low light? Nikon 17-55mm f2.8 if budget allowed. Else Tamron 17-50mm f2.8 also not bad("bad image quality ler...." Nothing to complain, some more it's not super obvious la.. For my level I can't even tell is that really bad image quality.. Unless you shoot to earn money like one of my photo kaki who shoot and sell 1 photo to media for around 5000sgd..
)
Just my opinion.. If really low light f1.8 or f2.8 can't help anything.. Get an external flash is the best....
Go get 1 from B&S and try, if not happy with it then losing $20-$30 dollar and let go.. Cheaper than you rent those lenses. Tried then only know what you want or don't want.. Meat for someone might be a poison for another one. Don't trust internet review too much, many just monkey see monkey do... Not surprise that someone who keep telling you f1.8 good bokeh good lowlight but he never hold SLR camera before... Internet mah....
Please correct me if what I mentioned got mistake.. I just wish to share what I tried & error.... :embrass: