understanding wide angel lens.

Im getting a lens. I look my 15mm to 55mm to help understand what angle of view I want (I do not know if I wrote that correct) I like the more wide angle. I can not compare like that can I?
Nikon 35mm 1.8g view angle is 44 degrees and magnification is 0.16x
The 50mm 1.8d has a view angle of 46 degrees and magnification of 0.15x
I want to choose a lens mostly by what I can get on the photo.
The math between the focal length and the sensor must be constant for a prime lens. So is the lens changing the angle? bending the light?
I think writing this made me understand but Ill post anyway in hopes to learn more.
How does this affect image quality?

“view angle” with what size sensor? That’s the question. A full frame sensor is going to give you wider view angle than a crop sensor, like APS-C/DX… B&H lists the 50mm as having a 46 degree, and 31 degree on DX. So the 35mm has a 44 degree on DX, and something considerably wider (maybe around 60 degrees) on full frame. If you look up a view angle calculator, you’ll find that these numbers are roughly accurate.

The smaller the focal length, the larger the view angle of the lens. But the angle visible on your photo also depends on the sensor size.

Does this answer your question?

Ya, means I made a mistake. I looked at the charts such a long time, too many numbers, you think I would have seen my error. Now the 35 mm says 63 degrees. Thanks

Just a note to add: I’ve gotten two wide angle lenses before, one of the problems (with the quality) is that you get a lot of chromatic abberation (trichromaticisim).

Some lenses are worse than others, so make sure you get a good quality one.

I want a 35mm to shoot at car shows so I can get autos framed in little space. I got the nikon 50 f1/8 d for now. I read
“superb resolution and color rendition
high-contrast images even at maximum aperture”
but it will not auto focus on newer cameras. It saves me a lot of money.

I bought, and still have and use, a Nikon D1-X … the very first professional-grade digital camera that Nikon produced … precisely because it was compatible with all of my “old glass.” And I still use that “old glass,” having several times paid more for a lens than I did for the (gently used) camera.

Nikon sells many zoom lenses, which are very good and often very handy. The only rule is that you should never buy a lens that crosses the normal (55mm, for 35mm film). Such lenses are unacceptable optical compromises.

You should not see any sort of aberration or optical distortion in a quality lens.

There are specially designed “lens targets” which are designed to clearly illustrate the exact optical properties of any lens. The lenses are mounted to a camera that is a precise distance from and exactly parallel to the center of this target. (See here for a discussion of lens testing.) If you poke around the Internet enough, you should be able to find published test-results for most (e.g. Nikkor, Canon) pro-grade lenses.

However … I also have a favorite lens, bought decades ago when K-Mart stores still had a great photo section, which is actually a miniature reflecting telescope. There is no glass lens in it. It has all sorts of chroma and other “problems,” but if you know how to work around these, you can get razor-sharp pictures at a very considerable distance in low light conditions. I enjoy using it to photograph birds, especially when I’m surrounded by people with “thousand-dollar optical cannons” and my little lens is about four inches long and weighs nothing. I’m reaching out and grabbing great pictures with my “little toy.”

I got a kit, it came with 2 zooms. I’m glad to have as I want to shoot a rodeo, but these are not so sharp.
OK Im getting my head around this. I have a 23.5 x 15.5…no Im not getting my head around it. Something has changed from the time we all shot the same size film.
Is this why wide does not look so wide on my camera?
I searched and all I can find is complicated math.
something i should have known before I got a camera.
I can not find a calculator now, no time
Thanks for the info

I had to search for and found Chromatic Aberration, also known as “color fringing” or “purple fringing”, I do not like that.

kazinger, you should get yourself a FoV calculator. You can find free ones online, I got one for my android phone.
If you’re planning on getting anymore lenses for your crop sensor camera, you’ll want to calculate the FoV for the focal length(s) that you’re interested in.
Also if you want a decent wide zoom lens with relatively little CA(chroma aberration) check out Sigma’s 10-20mm. It does have more barrel distortion than something like the Tokina 11-16mm from what I hear, but that lens also has more CA than the Sigma 10-20mm as far as I can tell.
One other thing to be careful with regarding third party lenses is their tendency to give you more front and back focus issues than what the camera’s manufacturers lens would give. I’m sure other people can chime in on that too.

Something has changed from the time we all shot the same size film.

I don’t know much about photography conventions, but there were always different formats for filmmakers.

Is this why wide does not look so wide on my camera?

Yes.

It’s really pretty simple: the lens creates an image circle. The sensor is a rectangle. Overlay the two, and you will quickly see how crop factors work with different size sensors. The opposite problem is called vignetting, when the sensor is larger that the image circle.

And here is a page with some nice calculators.
http://www.tawbaware.com/maxlyons/calc.htm

Ya, I understand it now .
I just haven’t had what I would call a real camera since about 1982. I took a look at prices and full frame looks to be out of the question. So looks like the new cameras now will have more wide angle image distortion. But now I have tools to fix it some.
I did get a cheap 8mm, well cheap to most but not to me. It looks cool when you correct the wide angel distortion.
I stopped and took some pictures of a Harley and the owner came out and saw me, he wants a poster made and is giving me 50 dollars. This is the only money I have made from anything artistic in a long time. I plan to shoot the car shows and the rodeo. Shoot everything every I see. It used to cost $20 every 36 pictures, now they are free to shoot. You only pay for prints, no film. I like that.
I was trying to get the depth of field down in some shots but could not. I do not know if it was me or the 18mm to 55mm that came with the camera. Its low res the high res I believe could be sharper.



I took out a trash can, oil spots and some broken concrete. Then took it to Raw Therapee. added some vignette and minor adjustments.

Edit
I did a shooting camera recomposing the frame test. I think the results may have been bad so Im deleting.

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If your sensor is not centered over the pivot point, the sensor might be moving a considerable distance when panning for a recomposition. If you’re using a tripod, check and see whether the sensor is indeed directly over the pivot. If you’re shooting handheld, then I am not at all surprised that you lose focus when turning.

Also most lenses get soft when wide open, especially around the image edges–I don’t know what part of the image you’ve cropped in on for the recomposition, but if it’s in the extreme corner, then it’s probably going to be fairly soft at f1.4 and there isn’t really anything you could do other than close your iris a bit.

I did not consider soft edges. I had wide open to have a shallow DOF.
Some say do not recompose so I was testing to see if it was ok.
I did another test. I put a string on a pivot point and made a arc from the center and placed cans on the arc. I placed the camera on the pivot point. Some times the sensor over the point sometimes the end of the lens over the point. ( I would think the pivot point would be the focal point). any way the results look as if the cans near the edge of the frame was out of focus but I did not get consistent results. So I will not post.