50mm and 600d soft image ?

An Exception · 17 Feb 2013 at 14:07

Checking focus at f4 or 5.6 is pretty foolish tbh as it doesn't tell you anything about focus accuracy, except for the most extreme inaccuracies. I don't know anyone who buys a fast 50mm so they can shoot at f5.6, might as well stick to the kit lens.
Op should just test the lens properly shooting in raw to see if the lens front or backfocuses. If the lens focuses on target then op can rule that out and then consider other things like lens sharpness, Iso performance and the ability to hang on to details etc.

Rojin · 17 Feb 2013 at 15:53

That's a pretty sweeping statement! I know plenty of people with primes who don't ever shoot them wide open. They value the increased corner to corner sharpness and less distortion that a prime brings. The plastic fantastic should be nice and sharp at f4 and above, either the shooter is still having motion blur issues (if everything is blurred) or severe front/back focus issues. Stick it on a tripod and manual focus using liveview to test if the lens is sharp, then test AF in the same position to compare.

danoliver1 · 17 Feb 2013 at 16:33

I had a d7000 that was back focusing, live view shots were perfect but ovf shots were off even with maximum ft.
I used a printed chart to test af accuracy see here http://regex.info/blog/photo-tech/focus-chart
To test sharpness use f5.6. To test af use f1.8.

D.P. · 18 Feb 2013 at 00:43

Rojin said:
That's a pretty sweeping statement! I know plenty of people with primes who don't ever shoot them wide open. They value the increased corner to corner sharpness and less distortion that a prime brings. The plastic fantastic should be nice and sharp at f4 and above, either the shooter is still having motion blur issues (if everything is blurred) or severe front/back focus issues. Stick it on a tripod and manual focus using liveview to test if the lens is sharp, then test AF in the same position to compare.

I got to agree with you, although it is important to get good results a from a fast rime wide open they wouldn't only be shot that way. Too many people think you need paper thin doF at all times, when so many scenes including wedding portraiture deserve a much larger DoF to properly encompass the subjects.

As far as I am concerned fast primes have the large aperture for when they are absolutely needed due to lighting constraints or the background is particularly busy and recomposing is not an option,. Otherwise they are best used stopped down a little, not just to get improved IQ but to get a realistic DoF.

Interestingly enough the aperture of the human eye is around f3.5-f9 (depending on the brightness) and the area of the retina is smaller than 35mm FF. shooting portraiture at f4.0 can give very natural images with enough subject sharpness and enough background softness to separate the two.

An Exception · 18 Feb 2013 at 00:59

DP, I think your in a minority that prefer smaller apertures tbh. In wedding photography, it's usually the photographers I see that are shooting stopped down that are charging peanuts, that I think that says allot about what the market prefers.
If your going to shoot at 5.6 and the like, may as well just get a decent zoom. Comparing IQ from a pro zoom and a prime at F5.6 has surely got to take some serious pixel peeping to see any difference!

Primes can also have just as much distortion etc. it's not like it isn't easy to correct.

DampCat · 18 Feb 2013 at 01:13

Wow, i never shoot below 1/125 because i have shakey hands. I had no idea people could hand-hold at 1/60 and get good results.

Columbo · 18 Feb 2013 at 16:33

DampCat said:
Wow, i never shoot below 1/125 because i have shakey hands. I had no idea people could hand-hold at 1/60 and get good results.

I can get sharp results on my 85mm at 1/60th but generally don't go any slower than 1/80th as both my wrists have bone grafts and metal pins in them and can get shaky at times.

When I had my A77 I could easily get good results at 1/20th at 85mm due the sensor stabilization.

An Exception · 19 Feb 2013 at 00:22

I can get sharp results at 85mm 1/60, however it's a bit hit and miss.

a1ex2001 · 19 Feb 2013 at 09:51

Rojin said:
That's a pretty sweeping statement! I know plenty of people with primes who don't ever shoot them wide open. They value the increased corner to corner sharpness and less distortion that a prime brings. The plastic fantastic should be nice and sharp at f4 and above, either the shooter is still having motion blur issues (if everything is blurred) or severe front/back focus issues. Stick it on a tripod and manual focus using liveview to test if the lens is sharp, then test AF in the same position to compare.

D.P. said:
I got to agree with you, although it is important to get good results a from a fast rime wide open they wouldn't only be shot that way. Too many people think you need paper thin doF at all times, when so many scenes including wedding portraiture deserve a much larger DoF to properly encompass the subjects.

As far as I am concerned fast primes have the large aperture for when they are absolutely needed due to lighting constraints or the background is particularly busy and recomposing is not an option,. Otherwise they are best used stopped down a little, not just to get improved IQ but to get a realistic DoF.

Interestingly enough the aperture of the human eye is around f3.5-f9 (depending on the brightness) and the area of the retina is smaller than 35mm FF. shooting portraiture at f4.0 can give very natural images with enough subject sharpness and enough background softness to separate the two.

Regardless of real world usage if you want to test focus accuracy it's much quicker, easier and more accurate to do it wide open.

McGraw · 19 Feb 2013 at 13:01

My other half picked up the camera the other day and shot 300 more images of her products for the website. Unfortunately she left it in manual from my last time of using 1/20, ISO 400 and fill in flash and didn't pop the flash up.

Incredibly, most of them were absolutely fine. Not sure if I could do that at 88mm equivalent.

DampCat · 20 Feb 2013 at 18:12

ManCuBuS said:
I can get sharp results on my 85mm at 1/60th but generally don't go any slower than 1/80th as both my wrists have bone grafts and metal pins in them and can get shaky at times.

When I had my A77 I could easily get good results at 1/20th at 85mm due the sensor stabilization.

An Exception said:
I can get sharp results at 85mm 1/60, however it's a bit hit and miss.

This has actually blown my mind. I dont know why, but i just had no idea. I thought i was normal.

Jeez.

Invasion · 21 Feb 2013 at 09:49

Thanks for all the replies

This has now been sent back for a refund as I just wasn't happy with the images. I have owned, several DSLRs over the years: canon300D, Nikon D50, Nikon D80 and a Fuji S2pro. I have always had a 50 mm prime and been able to get nice sharp images even with jpg.

I have never had an issue with hand holding at 1/50th and getting sharp results that I can remember.
Still not sure if it was down to back focusing or the body itself maybe but something wasn't 100% in my opinion.

Going to maybe give Nikon another go, as I am told, they are ahead on sensor quality:at the moment. I wasn't 100% happy with the build quality of the 600D and after talking to canon they said it is a problem with the 600/650D that they are aware of.

Thanks again for the advice