Originally posted by Serkevan I have been shooting for a year and I know, before taking the camera from the belt, if the wide end of the zoom lens that's on the camera at that moment is not gonna cut it for that building. I also know that I have between zero and no need for any lens longer than 200 or so mm. I also, *also* know that I'd much rather shoot 135mm at 2.8 than 85mm at 1.4-1.8 from 3 meters farther away, because the background blur is not going to look THAT much different and I'm saving half a kg (and half a grand, hah) on the lens.
Seriously, this argument that you have to try everything for something that is literally two mathematical formulas that anyone can learn with half a week of reading up on basic optics is nonsensical.
First of all, the discussion started with having choices. By having choices I mean having the option to choose between the 135mm and the 85mm in the first place. Second, choosing lenses based on background blur is not enough because each lens act different in terms of af performance, contrast, chromatic aberrations , weight, the balance on your camera, etc. Third, maybe the background will be similar in terms of blur, but the look will be different on the models.
I had 135mm f2 lens and sold it because of the 85mm f1.4L which is way better than the old 85mm f1.2L lens. Not having an option for the 85mm focal lenght, I went to 135mm. As soon as I had the choice of a very good 85mm lens, I went to the store and I rented it to see if it worth replacing the 135mm with the 85mm.
Just 2 examples:
1. I had to choose between DA70mm f2.4 limited lens and the FA 77mm f1.8 limited lens back in the days I was shooting with K-3 II. Most people said that 77mm lens is better, but when I try it I found out that was a lot slow to focus than DA 70mm, had lot more chromatic aberrations than DA 70mm and wasn't as sharp as DA 70mm at f2.4. What that lens had was a better look than DA70mm. I end up buying the DA70mm because:
- I had choices when comes to a portrait lens
- I chose the best lens for my needs based on real tests and not by guessing which one is going to be better
Sure, I can read about it on internet like you suggested, but we are all different and your needs and expectations maybe aren't the same as mine.
2. I have both 85mm f1.4L and 85mm f1.8 lenses. I do shoot from time to time at f1.4, but I shoot more on f1.8 and f2. The 85mm f1.8 looked a lot better in terms of weight and money. All these changed when I had a corporate event and I compared side by side the f1.4 lens and the f1.8 lens. Pfff, what a difference in speed, rendering and overall shooting experience.
But let me give a short example between these 2 lenses. Look at the image from the left how good it is compared to the one from the right. Both images were shot at f.18, ISO 100, 1/200s, from a tripod, with 2s delay.
Look at the more balanced colors, look at the transition between the blur and the focus parts, look at the difference in exposure, look at overall image (assuming that the program I used to upload the image doesn't affect the quality), llok at how the red color look on both. And these images are in good light, smiliar to the ones used by reviewers on internet. In bad light the difference is even bigger and the grip is better, the af is better on the 85mm f1.4 lens. I kept both lenses because the 85mm is used when I want to travel light.
So, personal experience in my opinion combined with options to choose from are always better than buying gear based on mathematical formulas and internet reviews done fast, for clicks, followers and for money.