[peteer01]

I've seen far more professional and impressive comparison pics, including some here on Pixalo, but I thought the following two pics still might be interesting. I bought my first fixed focal length (50mm) lens recently and decided to compare it to my zoom lens at the same settings. My friend also has a fixed focal (30mm) but says he doesn't seen any real benefit over his super zoom (18-200mm) so I suggested taking similar comparison pics with his lenses.

Here are the two comparison pics:
Sigma AF 18-50mm f/2.8 DC EX macro Vs. Nikon AF NIKKOR 50mm f/1.4D
Sigma AF 30mm f/1.4 EX HSM DC Vs. Nikkor AF-S 18-200mm f/3.5-5.6 G IF-ED VR II DX

I know most everyone on this board will already know that fixed focal outperform zooms as the same focal length, but if they aren't educational, I hope the above two pics are at least entertaining!

[Markulous]

Simple and effective demonstration of fixed vs zoom. Arguably not totally objective nor scientific, but I'm sure it convinced your friend!

[peteer01]

Sadly, it didn't! He wanted to see the full size originals, probably to make sure I wasn't chosing a specific portion of the lens that benefited fixed focus. (All the photos are from the dead center, where AF was targeting.) And, he was arguing that while fixed focus lenses may be just slightly better at one specific distance, today's super zooms are being made so well that the difference is negligible. Part of the reason I did the comparison with his lenses is because he was telling me that the 30mm lens was the lens he used the least, and I wanted to help him realize some of the reasons he might want to take it out of his bag more often.

(As for me, I'm currently in love with f/1.4 bokeh and speed, improved image quality at settings my other lens can handle are just gravy on top.)

[Dave Canon]

I am sure that this does correctly reflect the differeenc between these two lenses.

However, zoom lenses have improved enormously in recent years so fixed lenses have been less popular. It really depends how much you are prepred to spend. My last generation of Canon Zoom lenses were definitely for convenience and would have been out performed by almost any fixed lenses. However, my more recent L series Zoom lenses are a marked improvement and possibly outperform the last generation of fixed lenses. It might have been interesting to compare the Nikon fixed lens with a professional level Nikon Zoom.

The current fixed lenses will still out perform the current zooms but the professional level modern zooms are certainly up for the job.

[Dave]

It backs up what I found here :- Budget prime vs Premium Zoom vs Pro Zoom lens

In an ideal world we would all use primes for optimum quality, but zooms are just to convinient & save us a fortune in relation to having numerous primes to cover a focal range.

[peteer01]

That's the link! That's what got me thinking about a prime lens way back when I first stumbled upon it!

[Dave Canon]

Dave tests were interesting. I would like to do something similar with my Canon lenses but I do not have a fixed lens.