The Importance of Focal Length over MP in camera selection

alecz

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The 5442-ZE is a great candidate to buy one and test it out. You can learn a lot from one camera and moving it around.

If 2MP is more your budget, the 3241 is a great choice as well to test and get familiar with them.
This helps me narrow down my search and I conclude I first need/want a varifocal (turret preferred) 2/4 MP with a minimum illumintion between 0.002 - 0.004 preferably built by Dahua or Hikvision.
The two options above fit this requirement but they are shipped from US to Canada, there's additional shipping costs and import fees. they just become very expensive.

I found Empire Tec store on AliExpress, but it's empty - no products available. Unfortunately, all other tools (Amazon.ca, newegg.ca, ebay.ca, and even Google shopping) do not return good results, they are filled with Reolink, other knockoffs, 8 MP cameras and so on.

So (hoping to not yet hijack the thread), what are the budget options for decent varifocal cameras available in Canada? So far there's the two Dahuas, anything else?
(should probably start my own thread after this :D, but I feel having options here makes the advice in this thread more "actionable"
 
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wittaj

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This helps me narrow down my search and I conclude I first need/want a varifocal (turret preferred) 2/4 MP with a minimum illumintion between 0.002 - 0.004 preferably built by Dahua or Hikvision.
The two options above fit this requirement but they are shipped from US to Canada, there's additional shipping costs and import fees. they just become very expensive.

I found Empire Tec store on AliExpress, but it's empty - no products available. Unfortunately, all other tools (Amazon.ca, newegg.ca, ebay.ca, and even Google shopping) do not return good results, they are filled with Reolink, other knockoffs, 8 MP cameras and so on.

So (hoping to not yet hijack the thread), what are the budget options for decent varifocal cameras available in Canada? So far there's the two Dahuas, anything else?
(should probably start my own thread after this :D, but I feel having options here makes the advice in this thread more "actionable"

Yeah there is some issues currently with AliExpress and Dahua. Your best bet is to reach out to @EMPIRETECANDY directly and he can work something out.

Regarding illumination, I personally don't pay attention to the minimum illumination specs...because those are under ideal situations with so many factors not known.

Almost every camera will say 0 LUX with infrared on, and we all know how poorly Reolinks perform at night in low light yet that is their spec....or even two different good cameras. The 5442 4MP2.8mm fixed lens camera will beat the socks off the 5241 2MP 2.8mm fixed lens and they both say 0 Lux with IR on.

Once upon a time manufacturers would at least say at what shutter speed that rating was based on. Most would say a 1/3 shutter. That is way to slow for anything. You need to run minimum 1/60 shutter to start to minimize blur.

But now they don't even provide that, so in most cases it is a wide open iris, slowest shutter the camera allows, and gain and brightness cranked to 100 so that they can get the lowest illumination number possible.

But nobody would run the camera in that configuration.

Some of the older cameras would give these kind of specs so you knew how the camera was setup to come up with the minimum illumination.

0.002Lux/F1.5 ( Color,1/3s,30IRE)
0.020Lux/F1.5 ( Color,1/30s,30IRE)
0Lux/F1.5 (IR on)


So of course, the faster the shutter, the more light that is needed.

But as more competition came out, manufacturers started playing games and tweaking the settings for getting the lowest lux possible, but that came at a cost of a configuration nobody would use. So they wouldn't say how the camera was configured to capture that minimum illumination rating.

They play these marketing games to make it look like the camera is better than it is for someone that is just chasing minimum illumination numbers. Kind of like how we rarely get the miles per gallon a car is rated for.

It is a tool, but I would prefer to see the reviews here with settings provided and make an educated guess as to if my light is more or less than the reviewer.
 

Webfont

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The two options above fit this requirement but they are shipped from US to Canada, there's additional shipping costs and import fees. they just become very expensive.

I found Empire Tec store on AliExpress, but it's empty - no products available.
2MP Lite AI IR Vari-Focal Eyeball IP Camera - IP Cam Talk Store no extra shipping costs to Canada from China. But FedEx will collect taxes.

That’s the same shipping method as from AliExpress BTW (before the Dahua “purge”)
 

Perimeter

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But on a more serious note, for Dahua cameras he suggests a maximum shutter of 2ms and a gain of 75 as starting point. Does that sound like a good idea to you?
I'll try it once it gets dark.
 

wittaj

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But on a more serious note, for Dahua cameras he suggests a maximum shutter of 2ms and a gain of 75 as starting point. Does that sound like a good idea to you?
I'll try it once it gets dark.
That is a horrible starting point. 75 gain is way too high. At night 2ms is way too fast except for stadium lights. A 75 gain would negate the faster shutter.

At night one should start at 16.67ms and move up and down from there.

In terms of getting the most out of the camera, here is my "standard" post that many use as a start for dialing in day and night that helps get the clean captures. You need to get off of default. These are done within the camera GUI thru a web browser.

Start with:

H264
8192 bitrate
CBR
15FPS
15 iframes

Every field of view is different, but I have found you need contrast to usually be 6-8 higher than the brightness number at night.

We want the ability to freeze frame capture a clean image from the video at night, and that is only done with a shutter of 1/60 or faster. At night, default/auto may be on 1/12s shutter or worse to make the image bright.

In my opinion, shutter (exposure) and gain are the two most important parameters and then base the others off of it. Shutter is more important than FPS. It is the shutter speed that prevents motion blur, not FPS. 15 FPS is more than enough for surveillance cameras as we are not producing Hollywood movies. Match iframes to FPS. 15FPS is all that is usually needed.

Many people do not realize there is manual shutter that lets you adjust shutter and gain and a shutter priority that only lets you adjust shutter speed but not gain. The higher the gain, the bigger the noise and see-through ghosting start to appear because the noise is amplified. Most people select shutter priority and run a faster shutter than they should because it is likely being done at 100 gain, so it is actually defeating their purpose of a faster shutter.

Go into shutter settings and change to manual shutter and start with custom shutter as ms and change to 0-8.3ms and gain 0-50 (night) and 0-4ms exposure and 0-30 gain (day)for starters. Auto could have a shutter speed of 100ms or more with a gain at 100 and shutter priority could result in gain up at 100 which will contribute to significant ghosting and that blinding white you will get from the infrared or white light.

Now what you will notice immediately at night is that your image gets A LOT darker. That faster the shutter, the more light that is needed. But it is a balance. The nice bright night static image results in Casper blur and ghost during motion LOL. What do we want, a nice static image or a clean image when there is motion introduced to the scene?

In the daytime, if it is still too bright, then drop the 4ms down to 3ms then 2ms, etc. You have to play with it for your field of view.

Then at night, if it is too dark, then start adding ms to the time. Go to 10ms, 12ms, etc. until you find what you feel is acceptable as an image. Then have someone walk around and see if you can get a clean shot. Try not to go above 16.67ms (but certainly not above 30ms) as that tends to be the point where blur starts to occur. Conversely, if it is still bright, then drop down in time to get a faster shutter.

You can also adjust brightness and contrast to improve the image.

You can also add some gain to brighten the image - but the higher the gain, the more ghosting you get. Some cameras can go to 70 or so before it is an issue and some can't go over 50.

But adjusting those two settings will have the biggest impact. The next one is noise reduction. Want to keep that as low as possible. Depending on the amount of light you have, you might be able to get down to 40 or so at night (again camera dependent) and 20-30 during the day, but take it as low as you can before it gets too noisy. Again this one is a balance as well. Too smooth and no noise can result in soft images and contribute to blur.

Do not use backlight features until you have exhausted every other parameter setting. And if you do have to use backlight, take it down as low as possible.

After every setting adjustment, have someone walk around outside and see if you can freeze-frame to get a clean image. If not, keep changing until you do. Clean motion pictures are what we are after, not a clean static image.
 

CanCuba

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That is a horrible starting point. 75 gain is way too high. At night 2ms is way too fast except for stadium lights. A 75 gain would negate the faster shutter.

At night one should start at 16.67ms and move up and down from there.

In terms of getting the most out of the camera, here is my "standard" post that many use as a start for dialing in day and night that helps get the clean captures. You need to get off of default. These are done within the camera GUI thru a web browser.

Start with:

H264
8192 bitrate
CBR
15FPS
15 iframes

Every field of view is different, but I have found you need contrast to usually be 6-8 higher than the brightness number at night.

We want the ability to freeze frame capture a clean image from the video at night, and that is only done with a shutter of 1/60 or faster. At night, default/auto may be on 1/12s shutter or worse to make the image bright.

In my opinion, shutter (exposure) and gain are the two most important parameters and then base the others off of it. Shutter is more important than FPS. It is the shutter speed that prevents motion blur, not FPS. 15 FPS is more than enough for surveillance cameras as we are not producing Hollywood movies. Match iframes to FPS. 15FPS is all that is usually needed.

Many people do not realize there is manual shutter that lets you adjust shutter and gain and a shutter priority that only lets you adjust shutter speed but not gain. The higher the gain, the bigger the noise and see-through ghosting start to appear because the noise is amplified. Most people select shutter priority and run a faster shutter than they should because it is likely being done at 100 gain, so it is actually defeating their purpose of a faster shutter.

Go into shutter settings and change to manual shutter and start with custom shutter as ms and change to 0-8.3ms and gain 0-50 (night) and 0-4ms exposure and 0-30 gain (day)for starters. Auto could have a shutter speed of 100ms or more with a gain at 100 and shutter priority could result in gain up at 100 which will contribute to significant ghosting and that blinding white you will get from the infrared or white light.

Now what you will notice immediately at night is that your image gets A LOT darker. That faster the shutter, the more light that is needed. But it is a balance. The nice bright night static image results in Casper blur and ghost during motion LOL. What do we want, a nice static image or a clean image when there is motion introduced to the scene?

In the daytime, if it is still too bright, then drop the 4ms down to 3ms then 2ms, etc. You have to play with it for your field of view.

Then at night, if it is too dark, then start adding ms to the time. Go to 10ms, 12ms, etc. until you find what you feel is acceptable as an image. Then have someone walk around and see if you can get a clean shot. Try not to go above 16.67ms (but certainly not above 30ms) as that tends to be the point where blur starts to occur. Conversely, if it is still bright, then drop down in time to get a faster shutter.

You can also adjust brightness and contrast to improve the image.

You can also add some gain to brighten the image - but the higher the gain, the more ghosting you get. Some cameras can go to 70 or so before it is an issue and some can't go over 50.

But adjusting those two settings will have the biggest impact. The next one is noise reduction. Want to keep that as low as possible. Depending on the amount of light you have, you might be able to get down to 40 or so at night (again camera dependent) and 20-30 during the day, but take it as low as you can before it gets too noisy. Again this one is a balance as well. Too smooth and no noise can result in soft images and contribute to blur.

Do not use backlight features until you have exhausted every other parameter setting. And if you do have to use backlight, take it down as low as possible.

After every setting adjustment, have someone walk around outside and see if you can freeze-frame to get a clean image. If not, keep changing until you do. Clean motion pictures are what we are after, not a clean static image.
On a humourous note, I'm surprised that the Control, V and C keys aren't worn out on your keyboard! lololol

On a serious note, always good advice. I'm waiting for my stadium lights to come on tonight so I can adjust the Colour4K/X and see how low I can run the shutter on the 2431s with their 1/3" 4MP sensor!
 
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Perimeter

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On a serious note, always good advice. I'm waiting for my stadium lights to come on tonight
Fingers crossed!
 

CanCuba

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Fingers crossed!
We're in a good location. Havana is prioritized for power (the poor folks in the provinces pay the price for this) and we're in the middle of the hospital zone which is even more of a guarantee.

That being said, there are no sacred cows.
 

alecz

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...
Start with:

H264
8192 bitrate
CBR
15FPS
15 iframes
...
Thanks for explaining the other points, but I have to ask:
why h264 instead of h265?
And how do you determine the bitrate(8192)?
 

wittaj

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Thanks for explaining the other points, but I have to ask:
why h264 instead of h265?
And how do you determine the bitrate(8192)?
The 8192 is a good bitrate to start for a 4MP camera. 4096 is a good starting point for 2MP, and 16,384 is a good starting point for 8MP.

The lower the bitrate, the less the quality of the image, and the higher the bitrate, the higher the quality, but to a point.

Sure you can run a 2MP at 16,000 bitrate but to most people they won't see a visual difference between that or 4,000, but the higher bitrate will consume storage at 4 times the rate.

So it is a balance act for your field of view to go up and down the bitrate until you find the sweet spot where increasing it doesn't show an improvement and decreasing it would show a degradation.

This will explain H264 versus H265 a little better.

H265 in theory provides more storage as it compresses differently, but part of that compression means it macro blocks big areas of the image that it thinks isn't moving. However, it also takes more processing power of the already small CPU in the camera and that can be problematic if someone is maxing out the camera in other areas like FPS and then it stutters.

In theory it is supposed to need 30% less storage than H264, but most of us have found it isn't that much. My savings were less than few minutes per day. And to my eye and others that I showed clips to and just said do you like video 1 or video 2 better, everyone thought the H264 provided a better image.

The left image is H264, so all the blocks are the same size corresponding to the resolution of the camera. H265 takes areas that it doesn't think has motion and makes them into bigger blocks and in doing so lessens the resolution yet increases the camera CPU demand to develop these larger blocks.

In theory H265 is supposed to need half the bitrate because of the macroblocking. But if there is a lot of motion in the image, then it becomes a pixelated mess. The only way to get around that is a higher bitrate. But if you need to run the same bitrate for H265 as you do H264, then the storage savings is zero. Storage is computed based on multiplying bitrate, FPS, and resolution.


1667974399793.png


In my testing I have one camera that sees a parked car in front of my house. H265 sees that the car isn't moving, so it macroblocks the whole car and surrounding area. Then the car owner walked up to the car and got in and the motion is missed because of the macroblock being so large. Or if it catches it, because the bitrate is low, it is a pixelated mess during the critical capture point and by the time H265 adjusts to there is now motion, the ideal capture is missed.

In my case, the car is clear and defined in H264, but is blurry and soft edges in H265.

Digital zooming is never really good and not something we recommend, but you stand a better chance of some digital zoom with H264 rather than a large macroblocked H265. I can digital zoom on my overview camera and kinda make out the address number of the house across the street with H264, but not a chance with H265 as it macroblocked his whole house.

H265 is one of those theory things that sounds good, but reality use is much different.

Some people have a field of view or goals that allow H265 to be sufficient for their needs.

As always, YMMV.
 

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I hear it said that 1 varifocal is needed to determine focal distances needed, and then to buy fixed focal length cameras...

How much cheaper is a fixed focal length camera than varifocal? Is there a rule of thumb like varifocal is 25% more expensive?
Besides that, I just never see fixed focal length cameras in the longer focal lengths. So even if I know I need 40mm, I'll never find that in fixed focal.
So, I end up looking for deals on varifocal cameras and simply set the focal length and forget it.


H265 is one of those theory things that sounds good, but reality use is much different.
I couldn't get good image quality on motion with h.265. Perhaps a video that is post-processed in h.265 can have superior image quality for the same storage space, but apparently real-time processing can't deliver the quality.

Tangent topic, but I tried using VBR to save disk space, and that messes with the i-frames rendering the scrub bar useless.

Finally came to the conclusion all those knowledgeable people did, that I need to run h.264 and CBR. It's a shame that the "advanced" features meant to improve image quality and save disk space are useless.
 
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jec6613

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I couldn't get good image quality on motion with h.265. Perhaps a video that is post-processed in h.265 can have superior image quality for the same storage space, but apparently real-time processing can't deliver the quality.
...
Finally came to the conclusion all those knowledgeable people did, that I need to run h.264 and CBR. It's a shame that the "advanced" features meant to improve image quality and save disk space are useless.
I've found there are some cameras that do H.265 well, Axis P and Q series for instance, but it requires significantly more processing power and software development on the camera itself. If your storage requirements are years, you can see how even a 10% improvement makes spending double or treble on the camera worthwhile because you're going to save more than that on storage over the life of the camera (and remember, enterprise storage is substantially more expensive per TB than throwing some skyhawks into a desktop). If you're spending less than $500 on the camera, there's at least a 90% chance that the H.265 support is just so that they can stamp it on the box for marketing.

For me, the real trick with H.265 was that for the same bitrate, it allows me higher image quality and lower CPU and power usage (NVDEC is substantially more efficient at H.265 than H.264, QSV users will find this reversed)
 

mephisto_uk

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I guess this is only relevant in BI, right? Getting a NVR that has these capabilities baked in should in theory just do it?
 

badandy996

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Yeah, that camera would be about 60 degrees pulled all the way out. At this zoom, it is about 14 degrees or so. Not zoomed in at all, this camera would be roughly half the view of a 3.6mm camera.

But you would never use this camera at the smaller focal lengths, you would use a different camera.

That is the biggest aspect that people need to recognize that the 2.8mm focal length gives you a wide-angle view, but that comes at a cost of not being able to IDENTIFY at distance.

As the focal length gets larger, the field of view gets smaller. This allows you to IDENTIFY, but it comes at the expense of not being able to see a wide area.

That is why it is best to utilize a combination of different cameras and focal lengths - wide angle to see everything, zoomed in cameras to pinch points, to possibly complimenting the coverage with a PTZ that uses a fixed cam to spin the PTZ to the area of interest.

This is a pretty good website at being able to pull your house up and select cameras and get an idea of how wide you can see. However, I wouldn't go by the representative sample image for anything much beyond 30 feet.

Any other sites. Time limit is too short to set up something to toy with.
 

wittaj

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Any other sites. Time limit is too short to set up something to toy with.
Yeah they made that a paid service.


This would be the next one to try:

 
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