Need a prime: Help me to analyse my focal length

Currently, I have 2 lenses: 15-85mm and a 50mm/1.4
I would like to buy an other fast prime that I can use without flash. The 50mm is often too narrow in confined spaces.
I analyzed the 'keepers' of a longer period of using both lenses. Based on that, which lens would you buy? (Currently, I am thinking of the Canon 28mm/2.8 IS and the new Sigma 35mm)

I wouldn't call a f2.8 prime fast nor suitable for indoor, and IS is only useful for shooting static stuff.

Sigma 35 is an overkill on crop, unless you are going ff soon.

My recommendation is the new Sigma 30 Art. Fast, resonable price and sharp.

Sigma 30 Art, no question

You do seem to favour 35mm, and 85mm. Since 85 is not one of your choices, I wholeheartedly recommend the Sigma 35. It is an absolutely stunning lens, and is just as fine on crop as on FF. You could alternatively save a bit of money and go with the new Sigma 30/1.4, although that is not quite as good as the 35 IQ-wise.

35 L

Sigma 30mm Art.

But if you don't have a flash, getting one should be your priority. Using f1.4 primes indoors without flash results in bad lighting and too narrow depth of field in most cases. Flash light bounced off ceiling and walls will give you a much more significant IQ boost than a f1.4 prime.

Your selected focal lenths are fairly evenly distributed. I think you will need to sort the photos you take and look more at what type of shots you use each one for, and if those will be the types of shots you want to get the prime for or not.

One other note, you select primes to shoot from that focal length to longer. For example, a 35mm prime covers your needs from 35mm to ~60mm or so via cropping. So if you were to get a 35mm prime it would line up with that spike in your set at 35mm, but it wouldn't cover all of the shots you took from 15mm to 34mm.

I see this sometimes with people who have a 24-70 zoom on FF. They think about replacing the 24-70 with a single 35mm prime. But unless they never use the wide end of the zoom this approach misses something. A better replacement for a 24-70 is a 24mm prime and a 50mm prime.

In short - primes can serve to replace zoom ranges longer than the prime, but not zoom ranges shorter than the prime. You can't crop wider.

Human nature. Give someone a zoom that goes from A(mm) to B(mm) and they will mostly use it at A and B. As mentioned already, look over your pix. Chart does not tell us anything really. Gene

gasrocks wrote in post #15875084
Human nature. Give someone a zoom that goes from A(mm) to B(mm) and they will mostly use it at A and B.

That's exactly what I thought when I saw the graph.

gasrocks wrote in post #15875084
As mentioned already, look over your pix. Chart does not tell us anything really. Gene

I looked today extensively over these pictures and try to sort out the most probable use. There is quite some outdoor and technical stuff I shoot and most of this is well covered with the 15-85.

I guess the most use is for taking candid / spontaneous pictures in social settings. That's what I am using the 50 mm the most. I do have a flash, but would like to have a shallow depth of field and/or ignore the flash. The 50 on my crop 60D is great to isolate a single person. But as soon as I want more then just one face then I often simply don't have enough space to move back. The 50 is just too narrow to give me the flexibility I would like in such a setting.

So: 35 or 28 or even 24?

And on an other note: Is there any reason to go for the 35L instead of the new sigma 35 -- I am aware of the alleged QC issues. Looking at the reviews, I can not recognise any technical reason why I should spend the additional money on an L.

drmaxx wrote in post #15875196
Is there any reason to go for the 35L instead of the new sigma 35 -- I am aware of the alleged QC issues. Looking at the reviews, I can not recognise any technical reason why I should spend the additional money on an L.

Nope.

Why exactly did you rule out an 85 when so many of your pictures are at that length?

15-85 is a very limited range, IMO. You need to try out some 105, 135, 150, 200, etc.

vengence wrote in post #15875226
Why exactly did you rule out an 85 when so many of your pictures are at that length?

To me the huge number of shots the OP took at 85mm suggest that his next lens consideration should include something like a 70-200 or 70-300 zoom.

I don't see a 'love' of 85mm focal lenght there, I see somebody who really wants a lens that reaches longer than the current 85mm limit he has.

The OP does not really know what an 85mm lens is though. His present one is f/5.6 = yuk.

I have the older Canon 35 F2 and it is used more than my other lenses. It is a very useful focal length on a crop. If I were getting a lens for indoor, lowlight shots of people, I would look at the new Canon 35F2IS. The Sigma 35 is pretty big and heavy for a fast prime. If you have micro adjust on your camera, then the Sigma becomes an option.