RScottie
TPF Noob!
- Joined
- May 27, 2025
- Messages
- 62
- Reaction score
- 77
- Location
- Kentucky!
- Can others edit my Photos
- Photos NOT OK to edit
I am new to "real" Digital Cameras having been out of the hobby for some time.
As such, most of my questions involve gear and all the settings that these wonderful cameras present.
I have a Canon EOS Rebel T7, an APS-C type sensor. Now I understand this to mean that this sensor is smaller than a full frame (35mm) sensor by a factor or 1.6.
And, my understanding is that this 1.6 factor has an effect on lenses that were not designed for APS-C cameras.
As such, per my understanding, if I put an EF lens on my camera body, I am actually getting whatever the focal length is times 1.6, thus a 50mm EF lens would effectively be 80mm?
Is this the correct "direction" of the math for these lenses?
I ask because I want a non-zoom prime lens for general use that is 50mm give or take a few mm, but not give or take 30mm!
I noticed that Canon has another lens that is an 40mm EF but it is slower at F2.8 instead of F1.8.
I would get closer to the field of view I am looking for with that 40mm lens (64mm) than I would with the 50mm (80mm) but I would give up the low light capability that is one of the things I am seeking.
Of course if my math is wrong and I have went in the wrong direction in regards to how the crop sensor camera "sees" these full frame lenses, the whole question is moot.
I may be overthinking this, which I am prone to do, but I appreciate any opinions on the choice of lens as well as whether or not my math is correct in regards to the full frame lens on a crop body.
As such, most of my questions involve gear and all the settings that these wonderful cameras present.
I have a Canon EOS Rebel T7, an APS-C type sensor. Now I understand this to mean that this sensor is smaller than a full frame (35mm) sensor by a factor or 1.6.
And, my understanding is that this 1.6 factor has an effect on lenses that were not designed for APS-C cameras.
As such, per my understanding, if I put an EF lens on my camera body, I am actually getting whatever the focal length is times 1.6, thus a 50mm EF lens would effectively be 80mm?
Is this the correct "direction" of the math for these lenses?
I ask because I want a non-zoom prime lens for general use that is 50mm give or take a few mm, but not give or take 30mm!
I noticed that Canon has another lens that is an 40mm EF but it is slower at F2.8 instead of F1.8.
I would get closer to the field of view I am looking for with that 40mm lens (64mm) than I would with the 50mm (80mm) but I would give up the low light capability that is one of the things I am seeking.
Of course if my math is wrong and I have went in the wrong direction in regards to how the crop sensor camera "sees" these full frame lenses, the whole question is moot.
I may be overthinking this, which I am prone to do, but I appreciate any opinions on the choice of lens as well as whether or not my math is correct in regards to the full frame lens on a crop body.