Consider two IPC camera models with the exact sensor size (1/1.8") and resolution (4MP) but different Max Aperture (F1.6 vs F1.8). I read the F1.6 cam would have better night vision. Can someone give me some idea the level of difference? Is it a visually noticeable difference between F1.6 and F1.8 for the same sensor size?
Max Aperture F1.6 vs F1.8 -- Noticeable difference?
- Thread starter crosis
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bigredfish
Known around here
It can be. There are other factors at play not the least of which are sensor size, IR/LED strength (supplemental light) and fixed vs variable focus.
For instance if a VF or ptz, the FStop will get bigger as you zoom. Most ratings shown are at zero zoom. So once you've zoomed a VF say 75% the FStop might be 2-3 or greater
For instance if a VF or ptz, the FStop will get bigger as you zoom. Most ratings shown are at zero zoom. So once you've zoomed a VF say 75% the FStop might be 2-3 or greater
bigredfish
Known around here
Here;s a few posts about the difference in aperture in the fixed lens 3.6mm 5442 series both with 1/1.8" sensors
Review: OEM IPC-B5442T-ASE-NI 4MP Pro AI Starlight Full-color Fixed Bullet
and this one adds the Color 4K cam to that comparison
Full Color Cameras worth it?
Review: OEM IPC-B5442T-ASE-NI 4MP Pro AI Starlight Full-color Fixed Bullet
and this one adds the Color 4K cam to that comparison
Full Color Cameras worth it?
Much appreciated, @bigredfish. I'll educate myself more. I'm considering the varifocal Dahua IPC-HDW5442T-ZE-S3 (F1.8) vs fixed Dahua IPC-HDW5442TM-ASE-S3 (F1.6) but still debating what lens and whether I need the flexibility of varifocal.
bigredfish
Known around here
Always go fixed lens if you know for sure, you’ll get a better nighttime image. But like many I have a few VFs which have come in handy as I played with the scene and decided I needed more or less distance.
I'm being instructed to purchase a Varifocal to test the distance of interest then to plug the cam's Web GUI zoom #s here to determine what fixed lens i require.
How accurate is the Focal Length Calculator in determining the right lens? If i were to settle on a fixed lens IPC it would likely be purchased from a non-Amazon source making returns difficult if the lens wasnt quite right.
How accurate is the Focal Length Calculator in determining the right lens? If i were to settle on a fixed lens IPC it would likely be purchased from a non-Amazon source making returns difficult if the lens wasnt quite right.
Unfortunately you will find there is no real comparison between the focal lengths of these cameras, not only across the same manufacturer, but others as well.
Heck even taking the 5442 6mm fixed lens and setting up the 5442-ZE to the equivalent 6mm and you will find the field of view is different for both. The 5442-ZE had to be set to a 9mm equivalent to get the same field of view as the 5442 6mm fixed lens.
You can see a member here demonstrated this:
ipcamtalk.com
Heck even taking the 5442 6mm fixed lens and setting up the 5442-ZE to the equivalent 6mm and you will find the field of view is different for both. The 5442-ZE had to be set to a 9mm equivalent to get the same field of view as the 5442 6mm fixed lens.
You can see a member here demonstrated this:
Comparison of a Fixed Lens and a Varifocal Lens Camera's FOV
I was testing out a new Dahua T5442T-ZE 2.7-12mm Varifocal camera (from @EMPIRETECANDY ) and was going to compare it's performance to the Dahua HDW5231R-ZE and the HDW5431R-ZE cameras, which are 2.7-13.5mm varifocals, along with the T5442TM-AS fixed lens at 6mm camera. The HDW5431R-ZE has been...
OMG, this whole camera world is killing me. Thanks for the link.Unfortunately you will find there is no real comparison between the focal lengths of these cameras, not only across the same manufacturer, but others as well.
Heck even taking the 5442 6mm fixed lens and setting up the 5442-ZE to the equivalent 6mm and you will find the field of view is different for both. The 5442-ZE had to be set to a 9mm equivalent to get the same field of view as the 5442 6mm fixed lens.
You can see a member here demonstrated this:
Comparison of a Fixed Lens and a Varifocal Lens Camera's FOV
I was testing out a new Dahua T5442T-ZE 2.7-12mm Varifocal camera (from @EMPIRETECANDY ) and was going to compare it's performance to the Dahua HDW5231R-ZE and the HDW5431R-ZE cameras, which are 2.7-13.5mm varifocals, along with the T5442TM-AS fixed lens at 6mm camera. The HDW5431R-ZE has been...
Yep LOL. As mentioned above, unless you know for sure that a fixed lens is what you need for the goal of the camera, the varifocal is the better choice.
I would rather take a slightly darker IDENTIFY image than a brighter RECOGNIZE image.
For example a 2.8mm fixed lens to IDENTIFY at 40 feet is the wrong camera regardless of the aperture size. A varifocal optically zoomed out to 12mm with an aperture of 2.0 will IDENTIFY at 40 feet better than a 2.8mm fixed lens at 1.6.
While this thread is aimed towards selecting focal length over MP, the same general principals and distance recommendations apply.
ipcamtalk.com
I would rather take a slightly darker IDENTIFY image than a brighter RECOGNIZE image.
For example a 2.8mm fixed lens to IDENTIFY at 40 feet is the wrong camera regardless of the aperture size. A varifocal optically zoomed out to 12mm with an aperture of 2.0 will IDENTIFY at 40 feet better than a 2.8mm fixed lens at 1.6.
While this thread is aimed towards selecting focal length over MP, the same general principals and distance recommendations apply.
The Importance of Focal Length over MP in camera selection
At the urging of several folks here, I created a thread to show the importance of focal length and how focal length can be more important than megapixels (MP). I mentioned some of this in the post regarding The Hookup’s latest video demonstrating different cameras, including one sold from a...