[fad2101]

As the great Johnny Nash once sang, "There are more questions than answers" <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='' /> Thanks for all of your input.



In my film days I only ever used prime lenses, I was a Minolta user, and had a 28mm f2.8, 50mm f1.7, 100mm f2, 135mm f3.5 (all Rokkors) and a Tokina 400mm. Unfortunately they all were pinched, and I then moved on to a Canon RT, with two zooms that I bought off a mate 2nd hand.



I have always been frustrated by the lack of speed with the low end Canon Zooms, and would love to go back to using prime lenses. But they now seem very expensive, back in the day Zoom lenses on film cameras were looked down upon, and there was a good market for affordable primes, the manufactures fulfilled that, my perception is that with the advent of digital demand for primes in the mid amateur market has all but dried up, and the only offerings are now for Pros.





I can't see myself going Full Frame in the near future (or being able to afford to do so), so my dilemma will continue, <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/unsure.gif' class='bbc_emoticon' alt=':blink:' /> the 60D and 15-85 with a fast prime now slips into pole position.

[Guest]

[quote name='bigf' timestamp='1290821364' post='4485']

As the great Johnny Nash once sang, "There are more questions than answers" <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='' /> Thanks for all of your input.



In my film days I only ever used prime lenses, I was a Minolta user, and had a 28mm f2.8, 50mm f1.7, 100mm f2, 135mm f3.5 (all Rokkors) and a Tokina 400mm. Unfortunately they all were pinched, and I then moved on to a Canon RT, with two zooms that I bought off a mate 2nd hand.



I have always been frustrated by the lack of speed with the low end Canon Zooms, and would love to go back to using prime lenses. But they now seem very expensive, back in the day Zoom lenses on film cameras were looked down upon, and there was a good market for affordable primes, the manufactures fulfilled that, my perception is that with the advent of digital demand for primes in the mid amateur market has all but dried up, and the only offerings are now for Pros.





I can't see myself going Full Frame in the near future (or being able to afford to do so), so my dilemma will continue, <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/unsure.gif' class='bbc_emoticon' alt=':blink:' /> the 60D and 15-85 with a fast prime now slips into pole position.

[/quote]

Keep in mind that with digital you can easily shoot up to iso800 without hardly any Iq sacrifice, so primes are only important for very low light or very shallow dof applications. In the film days you needed the speed of primes simply for getting shake free results because you wouldnt shoot film faster than ISO 100 (onslide ) or iso 200 on negative for optimal results. In addition the quality of zooms has improved a lot over the years, which means the 15-85 is practically at its optimum wide open (save for vignetting, which can be corrected in post). Your old primes normally needed to be stopped down two stops to deliver that performance.

[genotypewriter]

[quote name='jenbenn' timestamp='1290858090' post='4491']

so primes are only important for very low light or very shallow dof applications.[/quote]

Or plain good image quality... almost all zooms have so much CA in the corners it's off-putting to anyone who has used good primes. The only prime-like zoom is the 70-200 2.8 IS II. Yes, even the Nikon 14-24 has more CA than what good primes in that focal length have. And no... CA can't be "fixed" without losing detail, regardless of what people might like to think. Same applies to geometric distortion that zooms always have a lot of.





[quote name='jenbenn' timestamp='1290858090' post='4491']

In the film days you needed the speed of primes simply for getting shake free results because you wouldnt shoot film faster than ISO 100 (onslide ) or iso 200 on negative for optimal results.[/quote]

Agree





[quote name='jenbenn' timestamp='1290858090' post='4491']

In addition the quality of zooms has improved a lot over the years, which means the 15-85 is practically at its optimum wide open (save for vignetting, which can be corrected in post).

[/quote]

I agree that zooms have improved, etc. but I can't see how that makes being stuck at f/3.5-5.6, on a zoom out of all things, acceptable. I mean, I rather use a P&S if I can't take a fast aperture lens on my DSLR because that's the kind of shots you can do with a 15-85 3.5-5.6 IS that a fast prime can't do.





[quote name='jenbenn' timestamp='1290858090' post='4491']

Your old primes normally needed to be stopped down two stops to deliver that performance.

[/quote]

Which is not bad because if you stop a f/1.4 lens down by two stops it'll become a f/2.8... which is still better than a f/3.5-5.6 <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt=':blink:' />



GTW

[popo]

[quote name='genotypewriter' timestamp='1290924054' post='4511']

I agree that zooms have improved, etc. but I can't see how that makes being stuck at f/3.5-5.6, on a zoom out of all things, acceptable. I mean, I rather use a P&S if I can't take a fast aperture lens on my DSLR because that's the kind of shots you can do with a 15-85 3.5-5.6 IS that a fast prime can't do.[/quote]

Not everyone needs or even wants big aperture all the time. For example, in my main area of random wildlife, primes are very limiting and a big aperture is no advantage in the vast majority of scenarios. Adaptability to changeable situations is key so my serious lineup is two bodies both with -f/5.6 zooms on them. I find myself stopping down for more DoF more often than wishing I had more aperture. So why not have the flexibility of the zoom? The P&S is a non argument either. I have yet to see one that can even dream of comparing tracking AF even to entry level DSLRs and regardless of the pixel count the image quality from the small sensor dominates over any lens considerations.



Anyway, primes certainly do have their place, but they are no universal solution to everything. Over time, getting a mix of both zooms and primes for use at the appropriate time is probably optimal for most.

[Guest]

[quote name='genotypewriter' timestamp='1290924054' post='4511']

I mean, I rather use a P&S if I can't take a fast aperture lens on my DSLR because that's the kind of shots you can do with a 15-85 3.5-5.6 IS that a fast prime can't do.



GTW

[/quote]

Hope you dont mean to say that a 60d with a 15-85 is the same as your PS: Either you have a PS which no one else but you can buy, or youdont really know what you are talking about, here.

[Brightcolours]

There is a good way and a bad way to "combat" CA (of the measured by PZ variety).



If you are lucky enough to have a lens that has a linear progressing CA from the center to the edge, and the offending wavelength exactly matches the red, or green, or blue channel, you can correct the CA by shrinking or expanding the offending channel. This will increase contrast and will increase "detail". This is the DPP manner, as far as I can figure out.



It is not always that simple, though.



You can also hide the CA colours, by just adjusting the offending coloured edges. This will NOT enhance contrast, and not get back the detail lost by the CA. As far as I can figure, this is what gets done by in-camera CA "correction" like for instance Nikon JPEG output does.



About the 15-85mm and its small max. aperture: genotypewriter is of course exaggerating with his "can do that with a P&S", but he does have a point. Always just having a smaller aperture available WILL just always give you that big DOF standard look, like P&S's always give you too.



Also, what I said before has to do with that.... f5-5.6 in the portrait range really just is not sensible to me. So the 50-85mm range is not great for that. And usually, when I need "tele" I need MORE than 85mm, so it does not make much sense for that either.



So a 17/18-50/55mm f2.8 lens just always makes more sense. You have f2.8 in the portrait range, and will have f4 at the short tele range (with the Canon 70-300mm f4-5.6 IS USM, 70-200 f4 L's).



Another road could be for instance the Sigma 18-50mm f2.8 EX DC macro for the wide angle, or a UWA (Sigma 8-16mm, Tokina 11-16mm, Canon 10-22mm, Sigma 10-20mm f4-5.6) and a Canon 35mm f2 for normal prime and Canon 85mm f1.8 USM for portrait.

[Guest]

[quote name='Brightcolours' timestamp='1290953516' post='4519']





So a 17/18-50/55mm f2.8 lens just always makes more sense.

[/quote]

Wrong. I sold my tokina 17-50 for a canon 17-85 and couldnt have been happier with the decision. In fact the 17-85 has proved to be my "best selling lens" eg. more than half of the pics I sold were taken with that very lens. Its personal preference and shooting style that decides which lens you buy. No one lens "always makes more sense" to everybody.

If I am serious about portraits, I usually look for a evenly coloured background. Simply throwing a messy and distrcating backround oof will not give comparable results, its the method for the lazy yielding inferiror results. Finally comparing dof of the 15-85 with a point and shoot, is quite daring.

[popo]

[quote name='Brightcolours' timestamp='1290953516' post='4519']

So a 17/18-50/55mm f2.8 lens just always makes more sense. You have f2.8 in the portrait range, and will have f4 at the short tele range (with the Canon 70-300mm f4-5.6 IS USM, 70-200 f4 L's).[/quote]

No they don't. Again it comes down to intended uses. The f/2.8 zooms are not that wide, nor that long. In my example earlier, the f/2.8 itself is even a disadvantage and the extra zoom range is more important. If you're going to trade away zoom range for aperture, primes start looking more attractive.

[genotypewriter]

[quote name='popo' timestamp='1290940317' post='4514']

For example, in my main area of random wildlife, primes are very limiting and a big aperture is no advantage in the vast majority of scenarios.[/quote]

Popo, I was referring to the 15-85 in particular here... using, say, a 100-400 or a 50-500 for that kind of thing is not all that bad. I mean, even the 800 and the 1200 primes are f/5.6s <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />



GTW

[genotypewriter]

[quote name='jenbenn' timestamp='1290945530' post='4515']

Hope you dont mean to say that a 60d with a 15-85 is the same as your PS: Either you have a PS which no one else but you can buy, or youdont really know what you are talking about, here.

[/quote]

I guess you didn't read what I wrote carefully because by P&S I was referring to the "kind of shots" that you can do with a 15-85+APS-C that you can't do with a prime.



If it's serious landscapes, portraits, action, etc. you can do all those with a fast prime just as good and most of the time better than with a zoom.



So the kinds of shots that you can get exclusively with a 15-85+APS-C will have:



* Overall shake (due to the reliance on IS, instead of taking a tripod and locking the mirror up)



* Little subject isolation (due to the slow aperture)



* Inaccurate focus because of less light going to the AF (so forget any real tracking but DOF is so big like on a P&S or a handycam, tracking is not even a real issue)



* Subject blur except in good light (again due to slow aperture)



* Bad bokeh (the simpler optics of primes in combination with larger apertures produce better bokeh)



* Heavy CA (due to all the extra glass etc.)



So, effectively, the shots that you can do only with a 15-85 IS that you can't do with a fast prime are P&S-like, lazy-tourist shots. So for that kind of thing I much rather carry a smaller P&S like my Nex-5.



GTW