Lens Questions

I am renting 2 lenses, the Sigma 8-16 and Sigma 10-20 will get them Friday.......

Inspeqtor wrote in post #18350816
I am renting 2 lenses, the Sigma 8-16 and Sigma 10-20 will get them Friday.......

Good idea!

Snydremark wrote in post #18350969

Inspeqtor wrote in post #18350816
I am renting 2 lenses, the Sigma 8-16 and Sigma 10-20 will get them Friday.......

Good idea!

Thank you! I am also still considering the Canon 10-22 if I find the 8-16 too wide

Inspeqtor wrote in post #18351034
Thank you! I am also still considering the Canon 10-22 if I find the 8-16 too wide

I just mounted a Tamron 11-16mm APS-C lens on a FF body, to give you an idea of 10mm on APS-C (16mm on FF) vs. 8mm on APS-C (12.8mm on FF).
Ignore the vignetting and pay attention to the horizontal and vertical AOV...
at a shooting distance of 20', 10mm frames an area of 30' x 45' while 8mm frames an area of 37' x 56'

Wilt wrote in post #18351070
I just mounted a Tamron 11-16mm APS-C lens on a FF body, to give you an idea of 10mm on APS-C (16mm on FF) vs. 8mm on APS-C (12.8mm on FF).
Ignore the vignetting and pay attention to the horizontal and vertical AOV...
at a shooting distance of 20', 10mm frames an area of 30' x 45' while 8mm frames an area of 37' x 56'

Along the outside (glassed) wall on the right, 10mm views a 19' long distance, while 8mm views a 21.5' distance along the right. That is a 19' wall where the fireplace is.

Wilt,

Thank you very much for this. I really did not remember what vignetting meant until I saw this post. I know I did know what it meant years ago, but had simply forgotten what it was.

Were these two pictures taken with the same lens, but different focal lengths (with the camera body in same approximate position) for each shot?

I don't really understand what you are saying about the distance to the fireplace/far wall. You mention a shooting distance of 20' but then mention 19'?

Also you say you used a Tamron 11-16mm lens, but are some how showing 10mm and 8mm width shots from your 11-16mm lens?

Sorry I am not quite comprehending this just yet....

Inspeqtor wrote in post #18351119
Wilt,

Thank you very much for this. I really did not remember what vignetting meant until I saw this post. I know I did know what it meant years ago, but had simply forgotten what it was.

Were these two pictures taken with the same lens, but different focal lengths (with the camera body in same approximate position) for each shot?

I don't really understand what you are saying about the distance to the fireplace/far wall. You mention a shooting distance of 20' but then mention 19'?

Also you say you used a Tamron 11-16mm lens, but are some how showing 10mm and 8mm width shots from your 11-16mm lens?

Sorry I am not quite comprehending this just yet....

An 8mm wide angle on crop is going to look like a 8*1.6= 12.8mm on full frame. He is using the 11-16 a crop lens on FF at roughly 13mm to achieve that although with the vignetting from using a crop lens on a full frame body.

FEChariot wrote in post #18351151
An 8mm wide angle on crop is going to look like a 8*1.6= 12.8mm on full frame. He is using the 11-16 a crop lens on FF at roughly 13mm to achieve that although with the vignetting from using a crop lens on a full frame body.

Aaahh ok, now I get it....

Will the vignetting then not be as severe on my crop camera?

Inspeqtor wrote in post #18351158
Aaahh ok, now I get it....

Will the vignetting then not be as severe on my crop camera?

Here is the Vignetting map from TDP of what to expect from the Sigma on a crop sensor. 50D will look like 60D and every other 1.6 crop sensor.

http://www.the-digital-picture.com …est-Results.aspx?Lens=710

FEChariot sums it up nicely.

I mentioned 20' distance simply for FOV comparison at that distance, using 8mm vs. 10mm.
But I did not attempt to stand precisely 20' from the wall...a wall at an oblique angle to the lens at a stated distance means nothing (20' to where along the oblique wall?!).

In the example photos one could see detail of a chair back + chandelier (far right) moving to the left to the far built-in bookcase rear, and I merely wanted to provide a reference distance (21.5') for that visible area in the 8mm shot, so that the 10mm shot you would have an idea of how much less wall (2.5' less) you would see with 2mm longer FL.

Personally speaking, 8mm on APS-C is 'crazy wide' as opposed to 10mm being (for me) 'more than enough' and 11mm being (for me) 'plenty wide'.

You really need to know HOW to USE a WA lens properly, as it can include too much foreground vs. too much sky, and backgrounds can fade back in the distance at a size of detail too small to appreciate much 'detail'. And ultrawide easily introduces 'exaggerated perspective distortion' into someone's body when they stand only a few feet away.

A much smaller room (12' x 10') shot with 8mm AOV and 10mm AOV on APS-C (shot using FF camera and lens at 12.8mm and 16mm)

Are you planning to use it indoors? I can get outside later if you want to see outside comparisons between 8-10mm

Not much of a 'landscape' for its scenic merit, but this does illustrate the ultrawide characteristics

• backgroud receding into the detailless distance,
  
• the prominence of the foreground objects (a 20' deep rooftop),
  
• and the prominence of the sky
  

Here are 10 and 12mm, on the 7DII, for width comparison; ignore the horizon, these were simply shot by propping the camera on driftwood to get the FOV comparison <shrug>.

10mm

FEChariot wrote in post #18351162
Here is the Vignetting map from TDP of what to expect from the Sigma on a crop sensor. 50D will look like 60D and every other 1.6 crop sensor.

http://www.the-digital-picture.com …est-Results.aspx?Lens=710

Thank you. I do understand the 50D, 60D (and all other XXD cameras) will have the same 1.6 crop.

What I do not understand in the web example, is why do they show both the Sigma 8-16 on left side, and the Canon 10-18 on the right side.

What is the significance of that? I would have thought they would only have one lens choice there.

Inspeqtor wrote in post #18351634
Thank you. I do understand the 50D, 60D (and all other XXD cameras) will have the same 1.6 crop.

What I do not understand in the web example, is why do they show both the Sigma 8-16 on left side, and the Canon 10-18 on the right side.

What is the significance of that? I would have thought they would only have one lens choice there.

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forum: Canon Lenses

You have to mouse over the image to see the comparison image; it's not a split, side by side comparison. So, it's how they let you pick two lenses to compare.