Out of these two budget lenses, which would you choose?

Here is this. But it is not mine.

https://photography-on-the.net …/showthread.php​?t=1446583

My wife has the 18-200 .. it is a good lens (for her), and she has a sharp copy. It's a bit heavy and suffers from lens creep if you don't lock it when carried facing downwards.

I have the 18-135 STM and find it a great walk-about lens .. I use it on my 70D and SL1.

reefvilla wrote in post #17822989
Not sure what 15 on a crop is but on my 6d and 24-70, i never use 24mm.

15-85 on a crop T6 is 24-136 which is a really great range - >18-135 on a T6 is 29-216

The 2nd reason I recommended the 15-85 is that the T6s has a 24 megapixel sensor and you can easily make a significant crop to the image to gain added FL because of the sensor pixel density - unlike older 16 megapixel crop sensors. Using the 18 mega pixel density of the Canon 1Dx, the 15-85 on a T6 can act basically as a 24-200 when necessary with cropping.

I have mostly FF cameras but I do also have a c100 (super 35 sensor size) and 7D2II (crop). Because of this I purchased the 15-85 as a video lens - and I also own the Sigma 18-35 1.8 (fantastically sharp) which has been used for low light video and indoor sports. While the difference between 15 and 18 may not seem like much, it is not insignificant in tighter spaces and personally I would take 15 over 18 every time in a crop setup - especially with high pixel density sensors that can be cropped when required.

I don't know the 18-135 and 18-200 lenses you are asking about, but given they are both variable aperture, the 18-135 would have to be significantly sharper or significantly smaller and lighter for me to choose it over a lens that offered that much more reach.

wallstreetoneil wrote in post #17823975
15-85 on a crop T6 is 24-136 which is a really great range - >18-135 on a T6 is 29-216

The 2nd reason I recommended the 15-85 is that the T6s has a 24 megapixel sensor and you can easily make a significant crop to the image to gain added FL because of the sensor pixel density - unlike older 16 megapixel crop sensors.

I don't know the 18-135 and 18-200 lenses you are asking about, but given they are both variable aperture, the 18-135 would have to be significantly sharper or significantly smaller and lighter for me to choose it over a lens that offered that much more reach.

One of these days I will actually try the 15-85 f/3.5-5.6 (also a variable aperture lens). Although it's a bit older than the 18-135 STM, it still seems to have a great following.

The 18-135 STM seems equally (or even more) popular. It's kitted more than the 15-85, so that might explain why there are more users and more sales and re-sales.

The thing is, when the 18-135 STM is not wide enough for me, I use the 10-18 and no way do I use it at 15 -17 - it's almost always at 10-12. So, I doubt the extra 15-17 on the 15-85 would entice me to buy it. It's also a bit fatter and heavier (575g compared to 480g for the 18-135). Still, it might be more of a one lens solution.

If comparing against FF the difference between 15 and 18 is pretty much the same as between 24 and 28mm. Actually 18×16=28.8 and that extra .8mm makes up the additional approx 2.5% difference in the focal length ratios if you do the math on each. At these wide angles it doesn't take much change in FL to make a significant difference. The changes in question are about 15% of the longer FL in each case. At the Telephoto end the change between 250 and 300mm is the same as between 15 and 18mm at the wide end in percentage terms (To keep the comparisons the same, going from longer to wider in both cases is a 16.67% change in FL).

Back at the wide end, the 28mm was for many years about as wide as you could go, without resorting to what were considered to be quite specialist lenses. I would not really expect anyone who has mostly used 18mm lenses on crop cameras would particularly realise that they were missing out on much. If you have become used to using a 24mm on FF though you probably will notice the difference quite a lot. Personally although coming from a 35mm film background I never used anything wider than 35mm, and have not really worried about having 20mm as the wide end of my normal zoom on Canon APSC bodies.

Alan

BigAl007 wrote in post #17824591
If comparing against FF the difference between 15 and 18 is pretty much the same as between 24 and 28mm. Actually 18×16=28.8 and that extra .8mm makes up the additional approx 2.5% difference in the focal length ratios if you do the math on each. At these wide angles it doesn't take much change in FL to make a significant difference. The changes in question are about 15% of the longer FL in each case. At the Telephoto end the change between 250 and 300mm is the same as between 15 and 18mm at the wide end in percentage terms (To keep the comparisons the same, going from longer to wider in both cases is a 16.67% change in FL).

Back at the wide end, the 28mm was for many years about as wide as you could go, without resorting to what were considered to be quite specialist lenses. I would not really expect anyone who has mostly used 18mm lenses on crop cameras would particularly realise that they were missing out on much. If you have become used to using a 24mm on FF though you probably will notice the difference quite a lot. Personally although coming from a 35mm film background I never used anything wider than 35mm, and have not really worried about having 20mm as the wide end of my normal zoom on Canon APSC bodies.

Alan

I come from film, also. I didn't shoot wide 40 years ago because it simply was not available. Like Al says, 28mm was wide in the stone age. Depends on your preferences these days. I would feel completely stifled with a wide end of 20mm on apsc. I used a 10-22, and now have a 10-18, on apsc and find it nowhere near wide enough. I just sold my Rokinon 14, and bought a Rokinon 12mm FE for use on full frame. Now we're getting somewhere. I think you'd need to get to around 8mm on apsc for the same FOV.

I still have the 18-200, and I used it for many years. It is very convenient for travel. In fact, when my wife got into photography, she took this lens away from me, as she does not like to switch lenses when traveling. Many people here on POTN tend to look down on superzooms, but I never had an issue with it. The IQ I very decent. It exhibits some geometric distortion which can be easily fixed in PP like Lightroom. It does suffer from downward creep, but Canon designed in the lock.

Of course it is not an L lens, but you are not paying the L lens price for it. But it does well what is is designed for.

Sorry, no experience with the 18-135 of any flavor.

You guys kinda spurred me to try a quick focal length comparison. I used my old EF-S 55-250mm f/4-5.6 IS. This is for focal length only, not quality, though.

For reference, this is the vista as taken with a full frame camera @ 24mm:

IMAGE LINK: http://www.ipernity.co​m/doc/diamantstudios/3​6204054

Then I centred on the building for the comparison that's relevant here 105mm vs 135mm.

This is @ 100 mm (I set the lens a bit higher than the 100mm mark to try to get ~105mm but it still gave me 100mm, ah well, since when I set it at the 135mm mark it gave me 131mm, it's still OK, methinks):

Finally, I did a shot at 200mm and another one at 250mm.

200mm:

Thanks for posting the comparisons. I think your 250mm shot is as limited by f/16 as it is by 250mm. DLA on the XSi is about f/8. After that you get more and more diffraction. f/8 @ 1/100 should be a noticeably better shot.

Bassat wrote in post #17824807
Thanks for posting the comparisons. I think your 250mm shot is as limited by f/16 as it is by 250mm. DLA on the XSi is about f/8. After that you get more and more diffraction. f/8 @ 1/100 should be a noticeably better shot.

Yup, the XSi suffers quite a bit from diffraction apparently, as I think I just found out when all my snowflake macro shots with it were unusable, even though I was using a very sharp L lens; shooting at the same aperture with the 5D2 yielded shots that were acceptably sharp (I tried at f/11 to avoid diffraction but didn't notice much difference, and I needed as much DOF as I could get). But anyway, I'm digressing a bit and macro is a whole different application.

Mind, when I used the 250mm end of my lens I was usually shooting at f/5.6 or f/8, and the image was still soft (though certainly sharper than the old Sigma @ 200mm).