Decent Wide Lens

[drhowser]

I heard about that, it's the light heating the glass and distorting it. You need to use an nd filter to cut it out. About 1 stop per 30 seconds ought to do it.

 

[Oxygen Thief]

I've never noticed it and I've taken hundreds of long exposure / small aperture shots. I'd be looking at the tripod as the source of that before blaming the lens.

 

[Bigian88]

Me either and I'd never blame the lens for it. It would be something moving the camera (wind, unbalanced tripod etc) a small amount that would soften edges of the image.

 

[zombizza]

I love my Sigma 8-16mm. its my favourite lens

 

[ClmntGbrl]

I heard about that, it's the light heating the glass and distorting it. You need to use an nd filter to cut it out. About 1 stop per 30 seconds ought to do it.

Well thanks for the tip i'll try that.

I've never noticed it and I've taken hundreds of long exposure / small aperture shots. I'd be looking at the tripod as the source of that before blaming the lens.

Me either and I'd never blame the lens for it. It would be something moving the camera (wind, unbalanced tripod etc) a small amount that would soften edges of the image.

It's a natural behaviour of any lens from my experience though i didn't do any research on that subject. I have a few nd filters like ND 64 & ND 1000 to make really long exposures (several minutes for example) and i had this softening happening on many lenses. But you might be right, it could be vibrations on the tripod side. I always thought this was a physical aspect of the lens, i'll have to make "scientific" tests to draw a conclusion.



Thanks anyway !

 

[Oxygen Thief]

The only references I've found reference the softening of images, has to do with long lenses only... 'long lens distortion'. It's something you can't buy your way out of, it would affect the cheapest and most expensive lenses by the same degree.

 

[Dudman]

Well looks like we have a winner. Will get some money together and try out the Tonika.

Thank you all for your inputs, hopefully I'll get some great shots for you all.

 

[drhowser]

Just to be sure, maybe I should say that I was completely taking the piss.
Length of exposure alone won't affect sharpness unless there is another factor involved, as has been said it will almost certainly be movement somewhere.

 

[Oxygen Thief]

Just to be sure, maybe I should say that I was completely taking the piss.

Turned out to be a real thing though LOL.

 

[ClmntGbrl]

Yes, i think i was in denial (no it can't be me that hit the tripod !!!!!)
but i think it's right to say that this may be cause...!

 

[drhowser]

Turned out to be a real thing though LOL.

Hahaha! Surely not for the reason I gave? I had a look on google first too just in case.

 

[Oxygen Thief]

Hahaha! Surely not for the reason I gave? I had a look on google first too just in case.

Close enough for me to find it based on your explanation !

 

[drhowser]

Close enough for me to find it based on your explanation !

Well fuck me then,

I mean it makes sense physically, but i'm amazed it will affect the result

 

[Oxygen Thief]

Well fuck me then,

I mean it makes sense physically, but i'm amazed it will affect the result

It's not the heating of the lens though, it's a heat source between the lens and the subject, distorting the air.

 

[drhowser]

It's not the heating of the lens though, it's a heat source between the lens and the subject, distorting the air.

Got you, I was still thinking along the lines of the lens being somehow to blame for the distortion.