How to check lense sharpness

[zj2000]

I've been observing the discussions about lenses here with interest. Every now and then someone will say "make sure you test a few lenses and get sharpest copy".

Problem is how do you tell whether the lense is sharp or not in the shop? The lcd on my cam is really tiny 1.8" and I don think I've seen anyone bring a laptop along to the shop to test. So do you guys normally judge from the lcd?

[calebk]

Originally Posted by zj2000 I've been observing the discussions about lenses here with interest. Every now and then someone will say "make sure you test a few lenses and get sharpest copy". Problem is how do you tell whether the lense is sharp or not in the shop? The lcd on my cam is really tiny 1.8" and I don think I've seen anyone bring a laptop along to the shop to test. So do you guys normally judge from the lcd?

Well, you could zoom in...

[zj2000]

Originally Posted by calebk Well, you could zoom in...

Is that the only way? I've thought about bringing a laptop along but not sure if it'll piss off the salesman...

[miniUltraman]

laptop not enough to check oso... bring in at least a 17inch LCD monitor

[miniUltraman]

Originally Posted by zj2000 Is that the only way? I've thought about bringing a laptop along but not sure if it'll piss off the salesman...

Just kidding.. actually you can bring a laptop or use the shop monitor if they have one.. I think Cathay staff are very friendly... they allow you to check. Please make sure you are genuinely choosing a lens and not just try-for-fun type.. I believe it is perfectly ok. But genuinely, zooming up in the LCD already can tell whether you got it sharp or not. Things to note is that the lighting within the shop may not be enough.. so if you are trying out a f4 or more lens.. you might not get enough light.. and that is not right to blame the lens and keep trying another one.. Just my 2 cents

[zj2000]

Originally Posted by miniUltraman laptop not enough to check oso... bring in at least a 17inch LCD monitor

If the serial number of the lense is in the exif then i really will take shots with a few lenses and bring home to slowly see... then go back and ask for the serial number I want...

[calebk]

Originally Posted by miniUltraman Just kidding.. actually you can bring a laptop or use the shop monitor if they have one.. I think Cathay staff are very friendly... they allow you to check. Please make sure you are genuinely choosing a lens and not just try-for-fun type.. I believe it is perfectly ok. But genuinely, zooming up in the LCD already can tell whether you got it sharp or not. Things to note is that the lighting within the shop may not be enough.. so if you are trying out a f4 or more lens.. you might not get enough light.. and that is not right to blame the lens and keep trying another one.. Just my 2 cents

Just to add on to that: one of the best places to test lenses is John 3:16. I say this not because I am a regular, but because they are really nice and patient. I can tell you because I've went there wanting to test lenses without intention to buy at that point in time, and they kindly obliged. Very good, 5 out of 5 star service.

[Jiaqing]

Went down to Cathay Photo earlier at Pen plaza and tested out 2 copies of the lens before buying. The sales staff were very friendly and happily brought me another lens to test.
Good and friendly service!

[cantaresg]

Why not just take some test shots on some pamphlets and zoom all the way. Tried that with the Olympus SP550UZ and it really gives instant feedback. In that you can tell whether the image is sharp immediately?

[zj2000]

Originally Posted by calebk Just to add on to that: one of the best places to test lenses is John 3:16. I say this not because I am a regular, but because they are really nice and patient. I can tell you because I've went there wanting to test lenses without intention to buy at that point in time, and they kindly obliged. Very good, 5 out of 5 star service.

Yup, I like John 3:16 also.... Problem is it's always packed... How about AP in funan? Less people..... Do you think they'll let me test?

[calebk]

Originally Posted by zj2000 Yup, I like John 3:16 also.... Problem is it's always packed... How about AP in funan? Less people..... Do you think they'll let me test?

The trick is to know when to go. Go in the slightly later part of the evenings, or in the afternoon at three or four, and don't go there on Sat, because that's the most crowded of crowded days.

[hazard]

On this topic...

1. how do you tell one lens is not as sharp as another?

2. what do you look out for?

3. Is the difference really discernible to a novice eye like mine?

[DeSwitch]

how i test sharpness of my lenses is to paste a $10 bill on the wall. place setup on a tripod making sure the height of the lens is the same as the $10. Place setup about 5M from the wall (more/less if yr lens min focusing distance varies) nearrer for wider lens. Use MLU and cable release. Shoot a few shots with different apertures settings. View image on LCD monitor. If you can see the fine lines on Yusof face clearly, den yr lens is considered sharp.

[hazard]

Ok thanks!

[yehosaphat]

Originally Posted by DeSwitch how i test sharpness of my lenses is to paste a $10 bill on the wall. place setup on a tripod making sure the height of the lens is the same as the $10. Place setup about 5M from the wall (more/less if yr lens min focusing distance varies) nearrer for wider lens. Use MLU and cable release. Shoot a few shots with different apertures settings. View image on LCD monitor. If you can see the fine lines on Yusof face clearly, den yr lens is considered sharp.

Must try this method!

[mcn]

tell me sister, what if u c a $50 note instead? sharp?

Originally Posted by DeSwitch how i test sharpness of my lenses is to paste a $10 bill on the wall. place setup on a tripod making sure the height of the lens is the same as the $10. Place setup about 5M from the wall (more/less if yr lens min focusing distance varies) nearrer for wider lens. Use MLU and cable release. Shoot a few shots with different apertures settings. View image on LCD monitor. If you can see the fine lines on Yusof face clearly, den yr lens is considered sharp.

[gryphon]

Originally Posted by mcn tell me sister, what if u c a $50 note instead? sharp?

no... time to change/get a pair of specs

[StrifeYun]

Originally Posted by gryphon no... time to change/get a pair of specs

hmm can we apply this theory for a LENS for GLASSES ? place ur head on table(tripod)

[CanonEOS]

Hmmm if we can see the lettering on top of the singapura word den is considered very very very sharp le

[pokiemon]

u can try reading this thread....

http://forum.clubsnap.org/showthread.php?t=226620